Pilar's Stairs

Third shift on the Anabasis was called the Quiet, and like most things aboard, the name had been chosen by a committee and then quietly earned.

Marisol Ibarra-Nakashima liked it. She liked the corridors with their lumens dimmed to eleven percent, the long amber runners along the deck seams like the last coals of something. She liked that the air handlers ran two degrees cooler, so that walking from the Spine out into the Ribs felt like stepping outdoors, if you had ever been outdoors, which she had not. She liked that nobody talked to her.

She was forty-one years old and had never seen a sky that was not a rendering, and she was, by the ship's reckoning, precisely as far from anywhere as a human being had ever been.

At 0212 she was on her back in the crawl behind Frame 40, elbow-deep in the guts of Photometric Channel Fourteen, replacing a cryo-shunt that had been drifting warm for six weeks. Fourteen was hers. She had claimed it the way people aboard claimed things — not by paperwork but by repetition. Fourteen had been her first solo call as a licensed hull tech, nineteen years ago, and she had botched it, and then unbotched it, and had come back to it every few months since like a woman returning to a stone she had once tripped over.

The channel was a photometer: a cold little eye in the flank of the ship, looking sideways through a slit in the ablation armor at nothing but a handful of reference stars. It did not take pictures. It did not do anything a colonist would ever thank it for. It counted photons and timed them, and it fed those counts into the navigation astrometry stack, where they were combined with eleven other channels and a gyroscope the size of a bus to produce, once a day, a number: the ship's position, its velocity, its heading, and the current best estimate of arrival.

Year 80. Arrival, Year 197. Everybody knew the numbers the way they knew their own weight.

"Fourteen, this is fourteen," Sol said into her collar. "Shunt's in. Bringing it cold."

"Copy fourteen." Pim, in dispatch, chewing something. Pim was always chewing something; the Quiet ran on stolen protein. "You want the stack held?"

"Hold the channel out of solution for ten minutes. Don't hold the stack, Nav gets weird."

"Nav gets weird," Pim agreed, with feeling.

The shunt took the cold beautifully. Sol watched the temperature curve on her slate fall away like a dropped rope, seventy kelvin, sixty, and the detector noise-floor dropping with it into that clean, black, ridiculous quiet where a machine could hear individual particles of light arriving from fourteen light-years away.

And then the counts began, and Fourteen sang to her, and everything in her life ended.

It did not feel like that. That was the strange part, and she would think about it for years afterward, in rooms she could not yet imagine: that it did not feel like anything. It felt like a small pleasure. It felt like recognizing a song.

Channel Fourteen looked at four reference targets, and the best of them — the loudest, the one the astrometrists loved — was a scruffy little binary the catalogues called RS-9 and the crew called the Lantern. It was two stars in a tight embrace: a swollen orange primary and a pinched red dwarf that went around it every 4.31 days. Every orbit, the dwarf crossed the face of the primary and took a bite out of the light. That was the clock, the metronome, dead regular, the reason the astrometrists used it.

But the dwarf was also a flare star. It was young and furious and it threw fits. Its flares came at random — genuinely random, magnetic knots snapping in a plasma no one would ever visit — spikes of light on top of the calm periodic dimming, sometimes three in a day, sometimes nothing for a week.

The result was a rhythm. A steady bass line with a drunk drummer on top of it.

Sol had a habit, from childhood, of turning data into rhythm. She had a hand drum in her bunk, a real one, made two generations ago out of a scrapped pump diaphragm and a hoop of laminate; she could not read music and could not carry a tune, but she could remember any pattern she had tapped once. It was how she had gotten through her certs. Vibration signatures, valve chatter, the four-beat stutter of a failing bearing — she drummed them onto her thigh and they stayed.

Nineteen years ago, on the botched call, she had sat in this same crawl at the end of a fourteen-hour shift and listened to Fourteen's raw counts on the audio channel, because the old techs said you should, and she had tapped along.

Four years ago — Year 76, month nine, when she had come back to replace this channel's whole detector head after a cosmic-ray hit cratered a pixel block — she had done it again. She had sat in the dark with her palm on her knee and drummed the Lantern for twenty minutes while the head came cold, and she had laughed out loud, alone, because the flare pattern that night had been so absurd, so exactly like something: dum, da-dum, rest, dum-dum-dum, rest, rest, DA. A stumble and a shout. She had thought: that's a hip-hop beat, that's a bad drummer on the fourth night of a bender, that's the sound of my Aunt Pilar going up the stairs.

She had named it, privately, the way you name things you don't tell anybody about. Pilar's Stairs.

At 0219 on the twelfth of the fourth month of Year 80, Channel Fourteen went cold, opened its eye, and played her Pilar's Stairs.

Dum, da-dum, rest, dum-dum-dum, rest, rest, DA.

Her hand was already going on her thigh. That was the thing. Her hand knew before she did; her palm slapped out the pattern in perfect anticipation, the way you sing the next line of a song you thought you'd forgotten, and she smiled in the dark with her tools on her chest and thought, well, hello, you old lush.

Then her hand stopped.

There is no reason for a flare star to repeat itself. That's what a flare star is. That's the entire content of the phrase. You might as well hear the same static twice.

"Pim," she said. Her voice sounded ordinary. "Pim, don't put Fourteen back in solution."

"Say again?"

"Keep it out. I want to run it standalone a while. Log it as detector burn-in."

"You got it." A pause; the chewing stopped. "Sol. Something wrong with the head?"

"Head's perfect," she said. "That's the trouble."

The hull shop at Frame 38 was hers by squatter's right during the Quiet: a bench, a bad chair, a wall of witness coupons in labeled clips going back to the Departure generation, and a terminal old enough that its casing had yellowed. She sat down without taking off her harness and pulled the archive.

Photometric records were kept forever. That was doctrine; that was in the Charter, article something: all instrumentation shall be retained in full fidelity for the benefit of arrival. Nobody had ever wanted to be the generation that threw away the data.

Year 76, month nine, night of the detector-head swap. She had the date because the work order had her thumbprint on it. She pulled the raw counts, the twenty-minute window she had drummed along to, and she laid them beside the twenty minutes she had just recorded, and the shop was very quiet.

Two curves. The eclipse ingress at the same phase. The flare at 4:31 into the window, a fast rise and a slow tail. The doublet at 6:02. The triplet at 9:40, 9:44, 9:51. The long dead patch. The big one at 17:58 that had made her laugh.

She sat back. Her mouth had gone dry in a way she recognized from decompression drills.

All right, she thought. All right. This is a caching fault.

That was the reasonable thing. Instrument stacks were full of caches. Somebody, somewhere, in ninety years of patched firmware, had left a buffer that could replay. She had personally found a temperature sensor in Ribs Four that had been reporting a very convincing lie for eleven years because a lookup table had gone circular. Machines were liars by default. Truth was a maintenance activity.

So she did what she would have done with any suspect channel. She took Fourteen out of its own signal path.

She switched the detector head to local storage, bypassing the stack. Different memory, different bus, different clock. Then she detuned the head's gain by four percent, so that anything replayed from a cache would come back with the old gain and give itself away. Then she waited nineteen minutes and recorded again.

The eclipse was in the wrong place now. Of course it was — 4.31 days, you don't catch the same phase twice by accident. The flares were different flares.

She exhaled. Her shoulders came down. She had time to think, thank God, and to feel foolish, and to consider getting a cup of the terrible shop tea.

Then, because she was the kind of engineer who finishes, she took the new nineteen minutes and searched the archive for them.

Not the same night. Not the same year. She wrote a matcher and let it walk the whole ninety-year record, all twelve channels, cross-correlating.

It found a hit in eight seconds. Year 62, month two. Then another: Year 71, month eleven. Then Year 76 again, a different window. Then Year 55.

The matcher kept finding hits. Sol stopped it at forty.

She got up, and walked to the far wall, and stood with her back against a rack of coupons, and looked at the terminal from across the room as if it might behave differently under observation.

Forty. Forty separate nights across twenty-five years in which Channel Fourteen had reported the exact same nineteen minutes of starlight.

She thought about it in the clean, slow way she thought about a pressure fault, where panic was a resource you spent later. If a cache were replaying, the loop would be short and the repeats regular. These weren't regular. She checked: the intervals between hits were untidy, months and years, no period. A shuffle. Something was drawing samples out of a bag.

And the gain change hadn't touched it. Different memory, different clock, and still the bag.

Which meant the bag was upstream of the detector head.

Which was impossible, because upstream of the detector head there was a slit in eleven centimeters of ablative armor, and beyond that there was the interstellar medium, and beyond that there was fourteen light-years of vacuum, and at the far end of it a star that had never in the history of the universe been asked to do the same thing twice.

Unless there wasn't.

Sol went back to the terminal and sat down and put her hands flat on the bench, and she said, out loud, to the empty shop, in the reasonable voice of a woman who fixed things for a living: "Okay. What else would be wrong."

Because that was the discipline. One instrument lying was a fault. Two instruments lying the same way was a design. And a design would have edges you could find in other places, if you knew where to put your hands.

She thought about it for four minutes.

Then she picked up her harness and went forward to listen to the Sand.

The Anabasis was, in cross-section, a spindle two point one kilometers long, spun for weight, and the front of it was a shield.

Everyone learned this at eight years old with paper models. At one-tenth the speed of light, empty space is not empty; it is a slow, unending sandblast. Hydrogen atoms come through like radiation. Dust grains a micron across come through like bullets. Over a hundred and seventeen years, that erosion would eat a bare hull to lace, and so the ship carried a Bow Cap: a stack of sacrificial plates, ice and laminate and foam, three hundred tonnes of stuff whose entire purpose was to be destroyed slowly and on schedule.

Sol's grade — Hull Optical & Sensing — did not maintain the Cap. That was Forward Structures, a proud, insular guild who wore their pitting scars like decorations and drank on the Anniversary of Ablation. But the Cap held windows, and the windows were optical, and so twice a year she went forward with Structures to swap coupons and calibrate the erosion telemetry, and once a year, on her own time, she went forward to listen.

Because the Sand had a sound.

It was not romance. It was a real, measurable acoustic: the impact of interstellar dust on the leading laminate, transmitted through the Cap's spars into the forward frames, a broadband hiss with a hard edge to it. In the old days they had used it as a crude velocity gauge, before the astrometry stack got good. Old-timers said you could tell the shift by the hiss. Old-timers said a lot of things.

Sol had first heard it at twenty-two, apprenticed to a woman named Bett Osei who had taken her forward to Frame 4, past the last human berth, into the cold volume where the ship stopped being a town and became a machine pointed at a target. Bett had handed her a contact probe on a coil of cable, the kind you use to find bearing chatter, and told her to put the pad against a spar and put the buds in her ears.

Sol had wept, a little, at twenty-two. She had heard the galaxy hitting the front of her house.

It was the only sound aboard the Anabasis that came from outside.

Frame 4 was a two-hour errand: three ladders, a long crawl through the utility spine where the spin gravity dropped away to almost nothing and your inner ear filed complaints, then the pressure door with its hand-painted sign, FORWARD OF THIS POINT YOU ARE CARGO. She logged it as a coupon pre-check, which was thin but not a lie. Pim didn't ask.

The cold up there got into her teeth. She found the spar she liked — Spar 7, a great flanged rib the color of an old nickel, sweating a little in the dark — and clipped the probe pad to it with a magnet, and set the gain, and put in the buds.

Silence.

Not zero. There was the ship: the sixty-cycle thrum of the coolant plant nine hundred meters aft, the tick of something contracting, her own heartbeat sounding out through her jaw. Sol knew all those. She filtered them the way you filter your own name in a crowd.

Under them: nothing.

She moved to Spar 6. Nothing. Spar 9, closer to the axis, where the spin noise fell away and the hiss should have been at its cleanest: nothing.

She turned the gain up until she could hear the electrons in the preamp, a soft frying sound, and beneath that she heard, occasionally, once every few seconds, a small distinct tick. And another. Sparse. Isolated impacts. Grains arriving one at a time, like the first three drops of a rain that never came.

At one-tenth of light, the Bow Cap should have been roaring.

Sol sat down on the deck in the almost-nothing gravity of Frame 4 with the buds in her ears and listened to that thin, patient ticking for eleven minutes. She did not think anything at all. She would try, later, to remember what she had thought, and there would be nothing there, just the cold coming up through her coveralls and the little ticks, each one a real grain of real dust arriving from a real universe, at a speed that meant her ship was barely moving.

Then she got up and went to the coupon rack.

The coupon rack was a Structures fixture, a steel frame in the forward vestibule holding sixty numbered slots. Every six months, a Structures tech went outside — a real EVA, tethered, the kind of thing that got you a certificate — and pulled a witness coupon from an exposed rosette on the Cap and brought it in and racked it here, so that erosion could be measured and the ablation budget updated. Sixty slots, thirty years of history. Beyond that the older coupons went to Archive.

Sol had handled dozens of these. They came in looking like a thing that had been in a sandstorm since before your grandmother was born: the mirror-polished face of them frosted opaque, micro-pitted to velvet, the leading edge rounded off. You could feel the erosion with a thumb. It was the most persuasive object aboard the ship. It was proof.

She pulled the most recent one, Year 80 month one, and turned it under the vestibule light.

Frosted. Velvet. Rounded edge. Perfect.

She let out a breath she had been holding for two hours and had to put a hand on the rack.

There. There it was. She had missed something; there was some other explanation; the Sand had a shadow up here she hadn't known about, some new baffle installed by Structures thirty years ago, some stupid simple thing that a woman from Optical wouldn't know.

She almost put it back.

But she had been doing this work for nineteen years, and the difference between a good tech and a bad one is what you do in the three seconds after relief.

She got out her loupe.

Under twelve magnifications, the pitting on a real coupon looks like the surface of the moon: craters at every scale, from ones you can see with your eye down to ones at the limit of the glass, and the small ones vastly, hopelessly more numerous than the big ones, because that's how dust is distributed. It's a fractal mess. It has depth. You can look into it for a long time and keep finding smaller things.

The coupon in her hand had craters. They were beautiful. They stopped, all of them, at the same size — a hard floor, nothing below about eight microns — and below that the metal was mirror smooth and utterly, chemically clean, and around each crater there was a faint annular ridge, a tiny raised lip, the same on every single one, like a rivet set by a machine.

Somebody had made this. Somebody had taken a polished coupon and shot it with a particle gun to a specification, and the specification had a resolution limit, and she was looking at it.

Sol stood in the forward vestibule of the generation ship Anabasis, eighty years out from a star she had never seen and one hundred seventeen years from one she never would, holding in her hand the manufactured proof of her own motion.

She thought, with awful clarity: this is a very old program.

Because that was the thing that made her hands start shaking, right then, and not before. Not the impossible star, not the silent Cap. It was the workmanship. It was the fact that somebody had thought this through — had understood that an engineer would come forward and put a loupe on a coupon, and had built a machine to fool her, and had run that machine, faithfully, twice a year, for decades, and had trained the Structures techs who racked them, or had never needed to, because the techs were fooled too, because a coupon from the rosette is a coupon from the rosette, and who looks?

She had. Once, at twenty-two, under Bett Osei's eye. She had looked at a real one then, and had never been able to unsee it, and that was the only reason she knew.

Sol put the coupon back in slot Y80-1, aligned to the notch, the way she'd found it.

Then she went and knelt at the base of the rack, where the frame was bolted to the deck, and looked at the deck plate under it, and did not know why until she found it.

A coin, welded flat to the deck under the rack, where no one would ever put a foot. An old ship's chit, the kind the Departure generation had carried out of Earth orbit as souvenirs and which now surfaced in drawers and in the mouths of the dead. Somebody had heated it and pressed it into the deck coating and then scratched into its face, with a scribe, in tiny letters:

COUNT THE PITS

And beneath that: A. F-S.

And beneath that, four tally marks, and a fifth crossing them.

Five.

Sol crouched over it in the cold with her breath going out in short bursts.

Five people, then. She was the sixth. Or the fifth had made the mark for herself and Sol was the sixth, or the marks were years, or names, or something else entirely. But it did not matter, because the shape of the thing had changed in one stroke and would never change back:

She was not the first.

She was up in the Ribs before shift-end, in a public alcove off the Frame 33 concourse where the lumens were coming up to dawn-amber and the first-shift bakers were already loud somewhere below, and she was searching the roster for a person with the initials A.F-S., and she was doing it on a public terminal with a guest token, because she had never in her life been paranoid and now she was, completely, as if a switch had been thrown.

There was one. There had only ever been one, in ninety years of a ship of nine thousand souls: Ansel Ferreira-Sunquist, born Y31, Hull Structures Grade IV, Forward Structures.

Deceased Y69.

Retired from service Y69, month seven, said the record, in the language the ship used for both machines and people. Cause: hypoxic event, EVA, Bow Cap Rosette 3. Full honors. Remains committed to the Grove.

Sol read it four times.

Ansel Ferreira-Sunquist, who had scratched COUNT THE PITS into a coin and welded it under the coupon rack, had died outside, at the rosette, on the plates, in the year 69.

She thought: that's a story about a man who went out to get a real coupon.

And then, because her mind would not stop working and she was beginning to hate it: or it's a story about a man who got one.

She sat back in the alcove. Two children went past below, on the concourse, arguing about something with enormous passion. The corridor smelled of yeast and warm laminate. A grow-light array came on somewhere and the whole Rib went a shade greener.

Eleven years before Sol was born, a man had known what she now knew.

And the ship had gone on. Eighty years of Milestones. The Departure Bell every year on the eleventh. The Half-Way Festival scheduled for Y98 with a committee already seated. Her nephew Tico, seven years old, who could tell you the arrival date and the name of the world — Hale — and who had a paper model of the spindle on a string above his bed with the Bow Cap colored in orange crayon.

Somebody would have had to do the arithmetic on that. On Tico. Somebody in a room had decided, sixty or eighty or a hundred years ago, what it was worth. ## The Long Rib

She walked home the long way, down through Frame 31 where the concourse opened into the Bowl and you could stand for a minute under two hundred meters of curved deck and pretend it was weather.

Morning aboard the Anabasis was administered. At 0600 the lumens went from amber to a pale wash the Programme called Highland, which had been chosen by referendum in Y44 over a warmer option called Coast, and at 0615 the air handlers pushed a trace of cut grass through the Ribs, and at 0630 the Bell rang once, low, from the speakers in the deckheads, and nine thousand people who had never heard a bell that was a bell felt their chests loosen a little.

Sol stood in the Bowl and let it happen to her.

On the far wall the Programme's board was cycling its morning content: DAYS TO HALF-WAY, 6,204. The Half-Way Committee's call for volunteers. A photograph of the Grove with the caption THEY CARRY US. The current Mood Index, which was published daily as a number between one and ten and which had not gone below six point two in eleven years, because morale on a generation ship was not a feeling. It was a resource. It was managed the way water was managed and air was managed, with reserves and rationing and a duty engineer, and the people who managed it were not villains; they were the reason there had been no third-generation collapse, no Riot of the Sixties like they'd had on the Cerro, no mothers walking their children out an airlock in the dark. Sol had grown up being taught to be grateful for them, and she was, and that was the trouble.

Because she was standing in the Bowl composing a list, and the list kept coming out wrong.

Who do I tell.

Nav. The obvious answer. Astrometry lived on Deck Two Forward and Sol had brought them coffee eleven times in nineteen years and been thanked for it eleven times without ever once being told anything. Nav consumed her channels. Nav produced the number. If the photometry was a bag of shuffled recordings, then either Nav knew, in which case telling Nav was telling the arsonist about the fire, or Nav did not know, in which case Nav was nine people who would go pale and then, being good, go up.

The Bridge. Same problem, larger.

Programme. Programme was the problem. Programme was the office that had printed THEY CARRY US.

Structures. Structures racked the coupons. She could not think of a way to tell Structures that they had spent thirty years handling manufactured evidence which did not begin with your rosette is a stage set, and Structures would answer that with fists, and possibly with love, because those coupons were their scars.

The Council of Ribs. Elected, twenty-two seats, real power over water and berth allocation and precisely no power over the astrometry stack, which had been placed by Charter under the Instrument Trust in perpetuity for the benefit of arrival. She had read that clause a hundred times on a plaque and never once heard it as a lock on a door.

Her sister.

Sol put her hand on the rail of the Bowl and looked down at the terraces where the first-shift crowd was thickening, and she thought: my sister, and then thought about what her sister did for a living, and made a small noise that a passing man mistook for a greeting.

"Morning," he said.

"Morning," said Sol.

The last name on the list was Pim, who was kind and had a mouth on him like a cargo door, and the name after that was nobody.

Nine thousand people. She could reach any one of them inside twenty minutes. She lived in a town two kilometers long where she knew four hundred faces and could not name one person she was certain would still be themselves at the end of the sentence.

She slept two hours and woke with her heart going.

Her berth was a Ribs-standard single at Frame 29: two meters by three, a bunk, a locker, a fold-table, and one indulgence, a real drum on a hook. On the fold-table, where it had been since the eleventh, was Tico's spare model of the ship — he made them constantly, out of ration card stock, and distributed them to relatives the way a cat distributes birds. The Bow Cap was orange. He always did the Cap in orange, because at school they showed the children an animation of the Sand striking the plates and glowing, and no part of the animation was a lie except the part where anything was moving.

She lay looking at it and did the arithmetic again and found she'd got it wrong at dawn.

Eleven years before I was born. No. Ansel Ferreira-Sunquist had died in Y69, when she was thirty years old, a licensed tech, working Ribs Four. He had been alive for the first two-thirds of her life. She had probably stood beside him in a lift. They had almost certainly been in the same room at the Anniversary of Ablation, which Optical was invited to and attended badly.

Somehow that was worse. Y69 was not history. Y69 was a year she remembered the food from.

She got up, drank the last of yesterday's tea cold, and understood that she was not going to tell anybody anything yet, because she did not have a number.

That was the discipline too. You do not go to a section chief and say the pressure feels wrong. You go with a figure and a method and a margin of error, and you go having tried, honestly, to prove yourself wrong, because the only currency an engineer has is that she has already argued against herself harder than you will.

Anyone she told would ask: how fast are we going, then, if not book speed?

And she did not know. She had a silence and a coupon and a haunted photometer. She needed to count the sand.

It took her three nights.

The first she spent building the rig, out of parts that would not be missed: four piezo pickups from a scrapped valve-chatter kit, a preamp, a bulk logger of the kind used for weld-stress surveys, and a length of cable long enough to keep the logger warm while the pickups froze. She built it at Frame 38 with the shop door open, whistling, in plain view of anybody, because she had worked out somewhere in the second hour that the only safe way to do a secret thing on the Anabasis was to do it boringly.

The second night she carried it forward past the sign that said FORWARD OF THIS POINT YOU ARE CARGO and clamped the pickups to Spars 6, 7, 9 and 11, spaced across four meters of the Cap's aft face, and left the logger running with a note taped to it: HULL OPTICAL — SPAR RESONANCE BASELINE — DO NOT UNPLUG — IBARRA-NAKASHIMA 14C. Nobody came forward during the Quiet. Nobody had come forward during the Quiet since Ansel had gone out and not come back, when the vestibule had become, without anyone deciding it, a small unofficial shrine that people avoided.

On the third night she collected it, and sat in the shop with the numbers, and made a discovery she had not expected, which was that she was angry.

Fifty-one hours of integration. Eleven thousand four hundred and six discrete impact events above threshold, distributed across four pickups and reconciled for double-counting: call it four thousand real grains, on a collecting patch she could calculate to within ten percent because she had the Cap's structural drawings and could work out how much frontal area drained its shock into her spars.

Then she pulled Structures' own acoustic archive, because Structures had been recording the Cap since Departure, quarterly, thirty-minute samples, filed as ACOUSTIC WITNESS and never listened to by a living soul.

The archive roared. Of course it did. Broadband hiss, the galaxy on the drum skin, exactly as Bett Osei had taught her to hear it, with a hard sizzling edge that meant velocity.

She ran her matcher on it.

Y80 quarter one was Y71 quarter three. Y79 quarter four was Y58 quarter two. Y77 was Y77 was Y63. The bag again, the same untidy shuffle, the same patient hand drawing samples out and laying them on the table with the date changed.

She sat with that for a while. Then she said, "You lazy sons of bitches," out loud, in the empty shop, and was surprised by how much of her voice it took.

Because that was the insult in it. They had not even generated new noise. Ninety years of a program that would fool anybody who did not look twice, run by people so certain that nobody would look twice that they had reused the same forty afternoons for a quarter of a century. And they had been right. They had been right for ninety years.

She did the velocity.

It was ugly work and she did it three times with different assumptions, because the impact rate scaled with speed but the detectability scaled worse — a grain arriving slowly delivered less energy into the spar and might sit under her threshold entirely — and she had to bound it rather than solve it. She used the local dust density from the Departure survey, which had been measured in the Sol system and might be wrong out here by a factor of three, and she said so in her own notes, in her own hand, on paper, because she had stopped trusting anything with a bus.

The answer came out between one-thirtieth and one-fiftieth of book speed.

Call it a fortieth. Call it seven hundred and fifty kilometers a second, which is a magnificent speed, which is faster than anything a human being had gone before Departure, and which was not, by a factor of forty, the speed on which the entire civilization outside this room had been built.

She did the last of it standing up, because she could not stay seated.

Eighty years at a fortieth of book speed. Two light-years of the journey, if you were generous, in eighty years. Call it a fifth. Not two. She had written two by reflex and had to scratch it out. Two-tenths of a light-year travelled. Eleven and a half light-years of the Hale run remaining.

At current speed: four thousand six hundred years.

She wrote the number on the paper and looked at it and it did not mean anything, so she wrote underneath it, in the same hand, the only figures that did:

Hull design life, certified: 400 years.

Closed-ecology drift study (Osei, Y58), projected failure of nitrogen cycle without external input: 600–900 years.

Tico: 7.

Then she folded the paper into eighths and put it inside the drum.

Bett Osei was in the Long Rib, which was what people called the care terraces at Frame 12 because everybody who went in stayed a long time and then left in one direction.

She was eighty-six. She had a chair by a grow-wall of runner beans and a blanket over her knees and one working ear, and when Sol came around the planter she looked up and said, "Optical," the way she had said it for nineteen years, half a curse.

"Structures wishes it had my hands," said Sol, which was the response, and Bett laughed her terrible laugh, three notes and a cough, and gestured at the stool.

They talked for a while about nothing: the bean yield, the new lift at Frame 15 that shuddered, a woman they both disliked who had been given a commendation. Bett's hands were mottled and enormous and had built two-thirds of the internal shielding in the Ribs. She had gone outside forty-one times. She was the only person Sol had ever met who spoke of the ship in the second person, as though it might be listening and might be persuaded.

At the third lull Sol said, "I went forward to Frame 4 last week."

"Mm."

"I put the probe on Spar 7."

Bett's face did not change. Nothing changed anywhere in the Long Rib; the misters came on over the beans with a small sigh, and somebody two terraces down laughed at something, and an orderly went past with a tray.

"And?" said Bett.

"And I couldn't hear anything," Sol said.

The old woman looked at the beans for what felt like a minute and a half.

Then she said: "Did you count the pits?"

Sol's hands went cold. She had rehearsed nine ways into this conversation and had not rehearsed being met halfway at a dead run.

"Yes," she said.

"How many marks were on the coin when you found it?"

"Five."

"Five." Bett shut her eyes briefly. "Then I'm the fourth. Nadia Okonkwo-Reyes was the fifth, and she went in Y77, so you're the first in three years. I'd started thinking there wouldn't be another. That's the thing about it, girl. You think you're the last one who can see, and you get very tired." She opened her eyes. "Did you put yours on?"

"No."

"Why not?"

"Because I wasn't sure it meant anything, and I didn't want to be counted before I'd decided anything." Sol heard how that sounded. "And because I was frightened."

"Good," said Bett. "Both. Good." She pulled the blanket up. "Ask."

So Sol asked.

And Bett Osei, who had taught her to hear the galaxy, told her about the Bloom.

Everybody knew about the Bloom. It was the second thing you learned in school after the Departure: in Y6, during the final boost stage, the aft drive had suffered a containment excursion; it had taken the number three and four tankage and eleven decks of the aft hull; one thousand four hundred and twelve people had been retired in ninety seconds, which was more than had died aboard in every other cause since combined; and the survivors had held the ship, restarted the remaining drive plant, and completed the boost late, at a cost of three years added to the schedule. That was why arrival was Y197 and not Y194. Every child on the ship could tell you that. It was the ship's founding wound and its founding pride. There was a mural of it at Frame 20, a great blue-white flower with figures silhouetted against it, and the figures were doing something heroic that no one had ever been able to specify.

"There was no restart," said Bett.

Sol sat very still.

"They got the plant scrammed and they got the fires out and they saved the ship, and that part is all true, and it was as brave as they say it was, and braver. But there was nothing to restart. The Bloom took the tankage, and it took the injector array, and it took the four hundred people who knew how to rebuild an injector array, and when they finished counting in Y7 they had a ship with a hole in her back doing seven hundred and fifty kilometers a second and no way on God's earth to go faster or, when the day came, to slow down."

"They could have turned back," Sol said. It came out of her before she'd thought it.

"Turned back with what?" Bett said, not unkindly. "Yes. That was the argument. There was fuel enough in one and two to change velocity by perhaps two percent. That will not turn a ship. There was a proposal to shape a return trajectory using the Hale star for a swing, which would have taken nine thousand years, and a proposal to make for a nearer system with nothing in it, which would have taken eleven hundred. There were four years of argument. Do you know what they voted on, in the end, in Y11?"

"No."

"They didn't vote on the trajectory. There wasn't one. There was nothing to vote on; the ship was going where the ship was going. They voted on the telling." Bett's enormous ruined hands lay in her lap. "Two thousand nine hundred adults, in the Bowl, over three days. And they voted, by something like four to one, that the children would not be told."

"Four to one," said Sol.

"They had just buried fourteen hundred people. Half of them had watched the ship's whole reason for existing get thrown out the back in ninety seconds. And they looked at their kids." Bett shrugged, an old woman's shrug, all shoulders and no hope. "You want me to tell you it was cowardice. Some of it was. Some of it was arithmetic. A ship is a thing that runs on people getting up in the morning. Try to build one that runs on despair, see how long the water stays clean."

"So they lied."

"So they built the Consensus," said Bett. "Which is the word they used, and I'll use it, because it's more accurate and I want you to be accurate. They didn't just lie. Any fool can lie. They engineered it, girl. They took the astrometry stack under the Instrument Trust so the Bridge could never be asked. They wrote the Programme charter. They put the flicker archives in the loop and the acoustic archives in the loop and they built a little machine — it's in a room at Frame 6, I've seen it, it's the size of a lathe — that shoots polished coupons with iron dust to a spec, twice a year, forever. They retired every record that contradicted the schedule; that's the word in the ledger, retired, same as for a person, and if that doesn't tell you what they thought they were doing, nothing will. And then they raised a generation that believed it, and that generation didn't have to be lied to, because they simply knew the truth, and the truth was Y197. And so on, and so on, and here we are."

"How many know now?"

"Now?" Bett considered the beans. "The Register. Two or three under her. The night crew at Six who run the coupon machine, and I think they're told it's a calibration rig — they might not know at all. And whoever finds the coin. Six of us, in thirty years. That's the beauty of it, do you see? It isn't guar

It isn't guarded."

Sol waited. The misters clicked off over the beans and the leaves went on dripping in the sudden quiet.

"That's what took me the longest to believe," Bett said. "Twenty-eight years, and I still catch myself looking over my shoulder in a corridor. There's no room full of men with a list, girl. There's no one who comes for you. The Consensus isn't a conspiracy. It's a maintenance schedule. It runs the way those misters run — on a timer, in the dark, and if the timer fails somebody files a ticket and a bored technician fixes it without ever once asking what the water is for."

"Then why is there a coin welded under a rack?"

"Because Ansel needed to know he wasn't mad." Bett's mouth moved. It was not quite a smile. "That's all it was ever for. He found it in Y52 — he was twenty-one, he was doing exactly what you did, he had a loupe because his mother had given him one and he thought it made him look serious. And he went four years thinking he was ill. He couldn't ask. Who do you ask? So he made a place where a person could leave a word that wasn't in any file and wasn't in anybody's mouth, and he put it where only a fool or a real technician would ever look, and he waited eleven years for the second mark."

"Who was the second?"

"A Nav man. Idris Vance-Oyelaran, astrometry, sharp as a scribe." Bett shifted the blanket on her knees. "He put his mark on in Y63. Then he went and told the Register. Three weeks later he had a Grade III certification he hadn't sat for and a berth in the Spine with a window bay, and he lived to be seventy-nine, and he never spoke to me again in his life. Not once. He'd nod. He nodded at me for sixteen years."

"They bought him."

"They promoted him," Bett said. "Which is cheaper and it lasts longer, and I'd like you to notice that it worked, because the day you start thinking these people are stupid is the day you get eaten. He wasn't weak. He was thirty-four and he'd just been told that the only two things he could do with the information were destroy nine thousand people's mornings or become useful. He chose useful. I've thought about him more than I've thought about my own brother."

"And the third?"

Bett looked at the beans for a while.

"Hana Petrossian-Bright. Optical, like you. She put her mark on in Y71, in the spring, and in the autumn she went out through the Frame 9 service lock without a suit and they wrote it up as a hypoxic event." A pause. "That's the phrase, do you see. Hypoxic event. It's a good phrase. It's true of everything. It was true of Ansel."

"What happened to Ansel?"

"He went out to get a real coupon," Bett said. "Y69. He'd been planning it two years. He wanted a physical object he could put in a Councilwoman's hand — he had it worked out that nobody argues with a thing you can hold, and he wasn't wrong, that was the best idea any of us ever had. He wanted to reach past the rosette to a spar face nobody had ever swapped, and cut a plate out of it, and bring it in with ninety years of nothing on it. Bare metal. Sixty-nine years of alleged sandblasting and a face you could shave in."

"Did he get it?"

"He got as far as the rosette." Bett's enormous hands lay still. "The report says his primary regulator iced and his secondary was found closed, and that's consistent with a man who did the drill wrong, and it's consistent with about four other things, and I've had thirty years to want it to be one of them and I still don't know. That's what they leave you. Not proof. Just the not knowing, forever, and the not knowing is free, it costs them nothing to make."

Sol found she had leaned forward with her elbows on her knees, and that her hands had wrapped around each other hard enough to hurt.

"You said you're the fourth."

"Y72." Bett pulled the word out slowly, like something with a barb. "I'd taught you to listen to that spar the year before, do you know that? I put the probe in your hand at twenty-two and told you that was the galaxy, and I believed it, and then a year later I went up alone to do a resonance survey and I heard three ticks in a minute and I sat down on the deck exactly where you sat down."

"I know," Sol said. "I felt where you'd worn the coating."

Bett laughed, that terrible three-note cough, and it went on longer than usual, and when it stopped she looked older.

"Twenty-eight years, girl. And do you want to know what I did with them?"

"You said you did nothing."

"I did worse than nothing. I did excellent work." Bett spread the ruined hands. "Two-thirds of the internal shielding in the Ribs. I built it to a four-hundred-year certification because that was the spec and the spec was the schedule and I knew the schedule was a lie and I built to it anyway, because the alternative was to explain myself to a stores clerk. I've walked past forty thousand tonnes of my own shielding thinking: at year four hundred and one that's going to start letting the sky in and somebody's great-great-grandchild is going to be standing under it wondering who signed for this. I signed for it. I signed everything."

"You couldn't have — "

"Don't," said Bett, quite gently. "Don't do that. I've done it for myself, plenty, and it doesn't hold water at eighty-six." She turned her head; her one good ear came round. "I told myself I was waiting for a reason to speak that wasn't just my own conscience wanting to be clean. That's a real thing, that's not nothing — you can wreck a ship with a clean conscience. But I got old waiting, and the truth is that after the first ten years the waiting became a kind of comfort. I had a secret and no duty attached to it. That's a very restful way to live. You want to watch for that. It's coming for you next week."

Sol said nothing. Two terraces down, an orderly was reading aloud to somebody, the same three sentences over and over, patient as a mister.

"The fifth," Sol said. "Nadia."

"Nadia Okonkwo-Reyes. Propellant archivist. Y74, she put her mark on, and Nadia was the only one of us with any courage that wasn't the stupid kind. She didn't go to the Register and she didn't go outside. She went to the Council." Bett said the word with a strange flatness. "She spent two years building a case a plumber could follow, and she took it to a Ribs member she'd been at school with — a decent woman, Sol, I want you to hear that, she was a decent woman with a decent record who'd never done a cruel thing in her life. And the decent woman listened to her for an hour and a half, and then she filed a P-7."

"What's a P-7?"

"Ask your sister," Bett said.

Sol's face did something. Bett watched it do it, without apology.

"It's a Programme referral," she said. "Category seven. Schedule-related distress. There's a name for it in the care taxonomy — chronological dysphoria, they've had it since the Twenties, which tells you how long they've been expecting us. It's not a punishment, that's what you have to understand or you'll misjudge them and lose. Nobody hurt her. She was cared for. She had a room and a keyworker and a very kind young man who came three times a week to help her with what he called her fixations, and they adjusted her sleep, and they gave her something for the agitation, and by the end she'd been moved down there — " Bett tipped her head at the far end of the terrace, past the beans, where the light was greener — "two terraces from me, and I went and sat with her every day for eleven months, and we talked about her mother's recipes, because that was what she could hold. And she died in Y77 believing the arrival year was one hundred and ninety-seven. She said it to me. She said, my grandchildren will see it. She didn't have grandchildren."

Sol looked at her own boots. The polish had come off the toes years ago and she had never bothered.

"They didn't take her memory," she said.

"No. They took her conviction, which is easier and doesn't need surgery. You don't have to make a person forget a thing. You only have to make being sure of it feel like being sick." Bett's voice had not risen once. "So. That's five. Ansel died outside, Idris was promoted, Hana went out a lock, I built shielding for four hundred years, and Nadia was loved to death by professionals. That's the whole record. That's every human being in ninety years who put their thumb on it and pressed."

"And now me."

"And now you," said Bett, "and you didn't put your mark on."

"No."

"Good, I said, and I meant it, and now I'm going to change my mind in front of you, so watch." She sat forward, and the blanket slid, and she let it. "Because you came in here with something none of us had, and you've been holding it for twenty minutes like a woman with a hot pan. What is it? You didn't come to be told about the Bloom. You'd have got the shape of that yourself by Thursday."

Sol reached into her coverall and took out the folded paper and did not open it.

"I counted the sand," she said. "Fifty-one hours, four pickups on the aft face of the Cap, reconciled for double counts. I bounded the velocity. It's between a thirtieth and a fiftieth of book. Call it a fortieth. Seven hundred and fifty a second."

"That's what it was in Y7," Bett said. "That's the number in the arguments. You're right."

"I know I'm right, that's not why I came." Sol unfolded the paper on her knee, and smoothed it with the flat of her hand, and did not look at it because she had it by heart. "Two-tenths of a light-year travelled in eighty years. Eleven and a half remaining. At current speed, four thousand six hundred years."

"Yes," said Bett.

"Hull design life, certified, four hundred."

"Yes."

"Your own drift study, Y58 — nitrogen cycle, six to nine hundred years without external input."

Bett went very still.

"You read that?"

"You wrote it," Sol said. "It's in the Trust archive under structural hygiene where nobody would ever find it, and it's the only honest document I've found on this ship, and you buried it in a filing category that means cleaning. That took me nine hours to find and it should have taken nine seconds. Why did you write it?"

And Bett Osei, who had gone outside forty-one times, put her hand over her mouth like a girl.

"Because I wanted there to be one place," she said, when she could. "One place where the real number was written down in my own hand. I thought — if it's in the file, then I've said it. Even if nobody ever — " She stopped. "It was cowardice with a footnote."

"It's a load-bearing footnote." Sol turned the paper around and held it up. "Bett. Look at what these are. Four hundred. Six to nine hundred. Four thousand six hundred. Every one of you found out that the past was a lie. Ansel, Idris, Hana, you, Nadia — you all found out about Y6 and Y11 and the vote in the Bowl, and every single one of you spent your life arguing about whether nine thousand people deserve to know what happened before they were born." She put the paper down. "That's not the question. That was never the question. It's a lie about a decision that hasn't been made yet."

The old woman's one good ear came round again.

"Say that again," she said. "Slowly."

"The Consensus isn't hiding the Bloom. Nobody cares about the Bloom, they've got a mural of the Bloom. It's hiding the fact that this ship is on a course that kills everyone aboard in four hundred years and cannot possibly reach Hale, and something would have to be done about that starting now." Sol heard her own voice go up and did not stop it. "Four hundred years of hull. Six hundred of nitrogen. Forty-six hundred to arrival. You don't fix that at the end. You fix that by becoming a completely different kind of ship, which takes generations, which takes a shipyard, which takes children who grow up learning the right arithmetic instead of colouring the Bow Cap orange because they think it's glowing. Every year we don't start is a year off the front of the only plan that could work. That's not a secret about history. That's a live fault, spending margin, at a rate we can calculate, right now, while we sit here."

Bett was crying, without any sound at all, and did not appear to have noticed.

"Nobody said it like that," she said. "In thirty years. Nadia came closest and she framed it as a moral question. She was so good, that's why they had her."

"I'm not good," Sol said. "I fix things. It's a fault report."

"They'll take you apart."

"Probably." Sol folded the paper back into eighths. "You said in Y11 there was a proposal to make for a nearer system. Eleven hundred years."

"Yes. A dwarf star with nothing around it worth having. There were three proposals and that was the least ridiculous. It needed a velocity change of about one and a half percent — they had two percent in tankage one and two, the tanks the Bloom didn't take. It was rejected because eleven hundred years was thought to be beyond the ship, and they weren't wrong either, girl, it was beyond the ship as she stood."

"Beyond four hundred years of hull. Yes." Sol was standing without having decided to. "But it's a hundred years better than eleven hundred now, and there'll be other geometries — anything you can still reach with a percent and a half of delta-v is a set that changes every year, because we're moving, and things drift out of it and things drift in. Nobody has recomputed that set in seventy years. Nobody's allowed to, because computing it means asking Nav for a true position, and the true position is under the Trust." She looked down at Bett. "Is the fuel still there?"

Bett opened her mouth. Closed it.

"I don't know," she said. "Structures doesn't touch tankage. I never — " Her hands came up, helpless, enormous. "In thirty years it never once occurred to me to ask. It was in the arguments in Y11 so I had it in my head as a thing that exists. Like the Grove."

"Who'd know?"

"Nadia would have known. That was her whole grade — propellant archives." Bett's face had begun to change; something was coming up in it that Sol did not recognise for a moment, and then did, and it was fury, eighty-six years old and still perfectly good. "She'd have known. She'd have known to the kilogram, and I sat with her for eleven months talking about her mother's escabeche."

"Reaction mass is inventory," Sol said.

"It's inventory."

"Inventory is public." Sol picked up her harness off the stool. "They hid the sky, Bett. They hid the sound of the sky and the marks on the metal and the position and the schedule. I don't think it ever crossed anybody's mind to hide the stores ledger, because nobody has ever in the history of this ship read the stores ledger for pleasure."

Bett Osei laughed, and it turned into the cough, and Sol stood and held her shoulder until it passed, feeling the bones in it like conduit under lagging.

"Go on then," Bett said, when she had her breath. "Go and read it. And Optical — "

"Structures wishes it had my hands."

"Structures wishes it had your nerve," said Bett. "Come back and tell me the number. Whatever it is. I've got maybe a year and I would like to have known one true number in this life that I didn't have to bury under cleaning."

The stores ledger lived where everything dull lived: in the Quartermaster's public directory, four levels down from a menu no one used, in a format that had not been updated since Y38 because it did not need to be.

Sol read it in the Frame 33 alcove at 1440 on a Thursday, on a public terminal, with a guest token, sitting in the open beside a vending stand that sold hot tamarind and a rack of Half-Way Committee handbills, while first-shift children ran shrieking along the concourse below. Nobody looked at her twice. This was, she understood by now, the whole architecture of the thing: the truth was not behind a door. It was in the least interesting room in the world.

CONSUMABLE INVENTORY — CLASS 4 — REACTION MASS & PROPELLANT

She had expected to have to work for it. It took eleven minutes.

Tanks 1 and 2 existed. They were real, they were pressurised, they had monthly gauge readings going back to Departure in an unbroken run, and the run went down.

Not fast. Nothing aboard the Anabasis went fast. A gentle, absolutely regular decline, month by month, decade by decade: a line so straight and so patient that she knew before she read a single allocation code that it was not a leak. Leaks were ugly. This was a budget.

She pulled the allocations.

ATTITUDE CONTROL, ROUTINE — 31.2%. That was honest; a spinning two-kilometre spindle wobbled, and you fought the wobble with mass out of a nozzle, and there was no other way to do it.

SPIN TRIM & PRECESSION MANAGEMENT — 22.8%. Also honest.

DEBRIS AVOIDANCE, LOGGED EVENTS (14) — 0.9%. Fourteen in eighty years. She would have liked to know what they had actually been avoiding, at a fortieth of book speed, and filed the question.

STATION-KEEPING RESERVE, RETAINED — the number that mattered, the bottom line, and she read it four times and then got out her slate and did the conversion herself from tonnes to metres per second, because she did not trust anyone else's arithmetic any more, and got the same answer twice.

Nought point three one percent.

Of the two percent they had held in Y11 — of the one and a half percent that would have bought them a dwarf star and eleven hundred years — there remained enough to change the ship's velocity by three parts in a thousand of nothing.

She sat back. Somebody's child went past dragging a toy on a string, singing a song about the Grove.

There was one more allocation line, below the reserve, and it was small, and it had a code she had never seen in a stores document in nineteen years:

OBSERVANCE — ANNUAL TRIM BURN (DEPARTURE BELL) — 0.34%.

She read it, and the concourse noise went a long way away.

The Trim.

Every year on the eleventh, at 0630, after the Bell, the ship burned. Everybody felt it. That was the point of it; that was the whole beloved substance of it. It lasted nine seconds and it came up through the deck into the soles of your feet, a long soft shove that made the hanging lamps in the Bowl swing all together, and you were supposed to stand still and let it happen, and children put a cup of water on the table the night before and lay awake to watch it ripple. Sol had done it. Sol had done it every year of her life, and at seven years old she had cried when she missed it because she had slept through, and her mother had let her put the cup out again the next morning and had shoved the table with her knee.

It corrects our aim, the Programme's handbill said. A hair's width now is a world's width in Year 197.

Nought point three four percent, over eighty years. More than the entire remaining reserve. Enough — she did the sum standing up, in her head, wrongly, then sat and did it right and got the same shape — enough, if it had been saved instead of spent, to have kept the Y11 dwarf-star option open until roughly Y50.

They had not lost the escape in the Bloom. The Bloom had left them one, thin and terrible and eleven hundred years long. They had blown it out of a nozzle, nine seconds at a time, so that nine thousand people could feel the ship moving with their feet.

Sol found that she had put her hand flat on the terminal casing, the way you do on a machine that is running rough.

"You people," she said, out loud, in the middle of the Frame 33 concourse.

The tamarind vendor glanced over.

"Sorry," she said. "Sorry."

Camila's berth was a Ribs-standard family at Frame 26, three rooms and a fold-out, with the good grow-window that came with Programme grade, and it smelled of onions and hot laminate and the particular sweetness of the cheap paper Tico used for his models.

"You look terrible," said her sister, opening the door. "Have you eaten? Don't answer, I know the answer. Ruel's got the shift. Tico — Tia Sol's here, and you are not to show her the — Tico."

Tico showed her the ship.

It was a new one, better than the last, forty centimetres of ration card stock with the spindle segments individually rolled and the spin ring on a paper axle so it turned, and, at the front, in orange, the Cap.

"It's not to scale," he said, ferociously, before she could speak. "It's not, so don't. The Ribs are too fat because otherwise you can't make the — "

"The frames are right," said Sol. She turned it over. Frame numbers, in a seven-year-old's hand, every four segments. "You've got Frame 4 on here."

"That's where it stops being a town." He said it exactly the way she had said it to him, in the same cadence, and she had to look at the ceiling for a moment. "That's where you go and you're cargo."

"That's right."

"Can I come?"

"When you're licensed."

"That's thirteen years."

"Then you'd better start," said Sol, and he made a noise of enormous injustice and took the ship off to the other room to add something to it.

Camila put a bowl in front of her and sat down across the fold-table with her own, and for a while neither of them said anything, which was one of the four or five reasons Sol loved her.

Camila was three years younger and had their mother's exact hands and had been, since Y71, an officer of the Programme: Observances, Grade II, which meant that when the Bell rang it was because a woman with those hands had signed the schedule. She was on the Half-Way Committee. She had been on it since it was seated, and she had a folder at home, a real physical one, because she liked paper, full of proposals for a festival six thousand two hundred days away: a procession the length of the Bowl, a new verse for the Bell, a scheme to have every child aboard plant something in the Grove on the same morning.

"You've got that look," Camila said. "The one from when you were doing your certs and you'd sit there working out how to tell me you'd broken something of mine."

"I want to ask you a work question."

"Then eat while you ask it, because you look like a coupon."

Sol ate two mouthfuls. They were very good; Camila could do things with a soy ration that ought to have required a court.

"The Trim," she said. "The Departure Bell burn. Who signs for the mass?"

Camila's spoon paused for perhaps a third of a second. Not guilt. Recalculation — the small adjustment of a person who has been asked about the boiler by someone who has never once asked about the boiler.

"I do," she said. "Observances signs the requisition and Propulsion executes it. Why?"

"How much?"

"It's fixed. It's been fixed since the Twenties. Four hundred and six kilos, one burn, nine seconds." She set the spoon down. "Sol, what?"

"Do you know what the line's called in the stores ledger?"

"Observance," said Camila. "Annual trim burn. I've typed it three hundred times." She was watching Sol's face now with a flat, professional attention that Sol had not seen her turn on anybody in the family before, and which was, she realised, probably very effective in a room. "That's the accounting category. Observance means the mass comes out of the ceremonial allocation and doesn't get charged against the operating reserve. It's an internal distinction. It doesn't mean the burn isn't real."

"The burn's real. I've felt it."

"Then what — "

"Tia Sol." Tico, in the doorway, holding the ship out in both hands, with something new added at the front: a little fringe of orange paper fibres teased out from the Cap and glued, sticking forward, so that it looked like a struck match. "It's the Sand. Miss Aduba showed us the animation and I did it with a pin, look, you have to fray it — "

"That's very good," said Sol.

"Is it right, though?" He was seven and had already learned the difference between praise and verification, and Sol thought, with a wrench, that's mine, I did that to him. "Is it right? When you go forward. Can you hear it? Miss Aduba says you can hear it hitting, if you put your ear on the metal."

The apartment was very warm. Somewhere on the terrace below, a door opened and a burst of music got out and was shut in again.

"You can hear it," said Sol. "You put a pickup on a spar and you put the buds in and you filter out the ship." She heard her own voice doing the thing it did when she taught, going slow and level, and she could not make it stop and could not make it lie. "It's the only sound aboard that comes from outside. It's the only one. Everything else in your whole life is us."

Tico's face did what a seven-year-old's face does when it has been given something bigger than the question.

"Can I hear it when I'm licensed?"

"Yes," said Sol.

He went. Camila watched the doorway until his footsteps had gone into the other room, and then she got up and closed the door, which she had never done in Sol's presence in twenty-six years, and came back and sat down and put both hands flat on the table.

"Say it," she said.

So Sol said it, in the right order, the way you write a fault report: observation, verification, falsification attempt, result, bound, implication. The Lantern and Pilar's Stairs and forty nights of identical starlight. The gain detune that proved the bag was upstream of the head. The eleven ticks a minute on Spar 7. The coupon with its pitting floor at eight microns and its little rivet-lips, machine-set, twice a year, forever. Fifty-one hours of integration and four thousand grains and a velocity bounded between a thirtieth and a fiftieth. Two-tenths of a light-year in eighty years. Four hundred years of certified hull. Four thousand six hundred years to Hale.

She did not say Bett's name. She did not say the coin. She had decided that on the walk over, and it had felt like closing a valve on her own arm.

Camila listened without moving. Her face went through nothing at all until the number four thousand six hundred, and then something happened under it, very fast, and was put away.

When Sol stopped, her sister said: "Is your slate in your pocket?"

"What?"

"Your slate. Is it in your pocket, is it awake, has it been listening."

"It's in the shop. In a drawer. Since Tuesday."

"Good." Camila let out a breath. "Good, all right. All right." She pressed the heels of both hands into her eyes and held them there. "You've had this how long?"

"Nine days."

"Nine days." A small, awful laugh. "Nine days. Sol, do you know that when you walked in I thought you'd come to tell me you were ill?"

"I might be. That's the other possibility and I've done the work on it, and if you want to take that route you should know I've done the work harder than you will."

"I'm not — " Camila took her hands down. Her eyes were red at the rims and perfectly dry. "I'm not taking a route. Don't do that to me, don't put me in the file before I've said anything."

"Fair."

"You've thought about what file I'd put you in, though."

"Cami, I've thought about nothing else for nine days."

They sat.

"The eight microns," Camila said at last. "That's the bit I can't — the star thing, I can't hold, I don't have the shape of it. The coupon I can hold. You're saying somebody makes them."

"There's a machine that does it. Twice a year. It's been running longer than either of us has been alive."

"And Structures racks them and nobody looks."

"I looked because a woman put a loupe in my hand at twenty-two and I got the habit."

"And the ledger." Camila's voice had begun to move now, quick and low, the way she used to talk when they were girls and she was working something out and did not want their mother to hear. "You said the ledger. The reserve."

"Nought point three one percent. And Observance has spent nought point three four."

"Since when?"

"Since Y19."

"So the Trim — " Camila stopped. Her hands were still flat on the table. "So the Trim has cost more than we have left."

"Yes."

"Say what that means. Say it in one sentence, in words, don't give me the units."

"It means," said Sol, "that if nobody had ever put a cup of water out on the table on the eleventh, this ship would still be able to steer."

Camila got up. She went to the counter and stood with her back turned and her hands on the edge of it, and Sol watched her shoulders, which were their mother's shoulders, and counted eleven seconds.

"I want to tell you what I know," Camila said to the counter, "and I want you to understand that I'm not defending it, I'm itemising, because you've itemised at me for twenty minutes and it's the only language you've ever respected."

"All right."

"I don't know about the star and I don't know about the coupons and I have never in my life heard anyone say the word fortieth. I'd have — " Her voice caught, and she took it in both hands and put it back. "I want that on the record, because I know how it's going to look to you in about five minutes, when I say the rest."

"Say the rest."

"There's a doctrine," said Camila. "Every Grade II gets it. It's not secret, you could read it, it's called Continuity and it's forty pages and the first line is: A generation ship is a story that must remain habitable." She turned around. "That's beautiful, Sol. I've thought it was beautiful for nine years. It means our job is not to make people happy — it says that, explicitly, page three, happiness is not an objective — it means our job is to make sure the thing people believe about themselves is strong enough to be lived in. Load-bearing. That's the word it uses. Load-bearing belief."

"Written by whom?"

"It doesn't say. It's been revised eleven times. The oldest annex is dated Y13."

"Two years after the vote in the Bowl," said Sol, and watched her sister not know what that meant, and believed her, entirely, and hated the relief.

"What vote?"

"Later. Go on."

"There's a taxonomy," Camila said. "Care categories. P-7 is schedule-related distress." She said it the way you name a bone. "Chronological dysphoria. It's a real thing, Sol, I've seen it — I sat with a man at Frame 19 who'd got it into his head that the arrival was a lie and he was so frightened he couldn't eat, and we got him a keyworker and we adjusted his light and in four months he was back at his bench and he sends the office a card. That happened. That's not a story they told me, I was in the room."

"Was he right?"

Camila's mouth opened, and shut.

"That's the question, isn't it," she said. "That's — God." She sat down again, heavily. "Nine years. I have never once asked whether any of them were right. Not because I was told not to. It never came up. He was a man who couldn't eat, and I fixed the man who couldn't eat."

"Cami."

"There's a spike," her sister said. "There's a P-7 spike every year in the fifth month, four weeks after the Bell, and we've always said it's post-observance depression, the let-down after a Milestone, it's in the literature." She was looking at the middle of the table. "People feel the burn and then they lie awake."

Sol said nothing at all.

"Ask me," said Camila.

"Ask you what?"

"Ask me the question you came to ask. Not the Trim. You didn't walk two frames at nine at night to ask me who signs a requisition." She lifted her head. "Ask me."

"If I said this to anyone else," Sol said. "Anyone. Pim. My chief. A Councilwoman. Anyone but you. What happens?"

"They file a P-7," said Camila.

"Would you?"

The pause was not long, and Sol was grateful for that, forever, afterwards.

"Yes."

"Cami — "

"No, listen to me, because you need this and you're not going to like the shape of it." Camila leaned in. "You think I mean I'd betray you. I wouldn't. I mean that if you say those sentences in a corridor to a person of goodwill, that person will be worried about you, and worry has a form, and the form is a P-7, and the form goes in, and after that nobody has done anything wrong and nobody can stop it. There's no room, Sol. There's no man with a list. I've been inside it for nine years and I've met the whole apparatus and it's about forty people who love this ship and a taxonomy and a scheduling engine, and it will take you apart with the tenderest hands you have ever felt in your life, and everyone involved will go home and sleep well, because they will have cared for you, and they will not be lying about that. That's what you're up against. Not a villain. A duty of care with ninety years of practice."

"Nadia Okonkwo-Reyes," said Sol.

Camila went white in a way Sol had only seen once before, at their mother's committal.

"Where did you get that name?"

"Y74 to Y77," Sol said. "Propellant archivist. She built a case and took it to a Council member who'd been at school with her, and the Council member filed. Eleven months on the second terrace at Frame 12. She died believing in Y197."

"That's a closed case file." Camila's voice had dropped to nothing. "That's — Sol, you can't have — that's inside the care archive, that's four levels of — "

"I didn't read a file. Somebody sat with her every day for eleven months and remembers her mother's recipes." Sol put her hands on the table, mirroring, deliberate. "And that person is eighty-six and has a year left and has never told anybody, and the reason is you. Not you. People like you, doing their jobs kindly. That's the whole security system. Kindness with a form attached."

Camila put her face in her hands and stayed there for a while. When she took them away she looked ten years older and, in some way Sol could not name, more like herself than she had all evening.

"What do you want," she said. "Actually. Not the report. You've got the report, it's flawless, I couldn't dent it if I had a month. What do you want, from me, tonight?"

And Sol found that she had it ready, and that it was not what she had rehearsed on the walk over.

"I want you to do the arithmetic on Tico," she said.

"Don't."

"You have to. It's the only calculation left that matters and it's yours, not mine — I've done mine, I'm an instrument tech, I fix things, I found a fault and I have to report it, that's the entire content of my life. But you're Programme. You do the other side. So do it." She was not angry; that was the strange part; her voice had gone very quiet and very level, the teaching voice again. "Tico is seven. On the schedule he believes, he dies of old age about a third of the way to Hale and his great-great-grandchildren land. That's a good life. That's a life inside a story that's habitable, your word, and I understand why four to one is a defensible number when the alternative is nine thousand people finding out on the same Tuesday that everything is over."

"Four to one — "

"In Y11 the adults voted, in the Bowl, over three days, four to one, that the children would not be told. That's where your annex comes from." Sol let that sit for a beat. "But here's what they voted on that they didn't know they were voting on. On the real schedule, Tico dies of old age about a fiftieth of the way to nowhere, and his great-great-grandchildren are alive when the hull certification runs out, and their children are alive when your nitrogen cycle starts to slip, and there is no landing, ever, for anyone, in any generation, unless somebody starts now. Not in a hundred years. Now. Because becoming a different kind of ship takes longer than the margin we have left, and the margin has been going out of a nozzle nine seconds a year for eighty years so that people could feel it in their feet."

"Stop."

"So do the arithmetic," said Sol. "Because I can't. I genuinely can't, Cami, I've tried for nine days and I don't have the grade. Tell me what's worth more: Tico believing in Hale for the next seventy years, or Tico's line having a chance of existing at all. That's a real question and I'm not being cruel, it's your profession, it's the only thing you know that I don't. You're the only person aboard I can ask who will actually answer instead of filing."

Camila did not answer for a long time. Out in the other room, something fell over, and was picked up, and a small voice said a word it had learned from an uncle.

"I don't know," she said.

"All right."

"No, I need you to hear that properly, because it's the first honest sentence I've said in nine years." Her sister's hands were shaking now, a fine tremor, and she looked at them with mild interest, as if they belonged to a colleague. "The doctrine has an answer. The doctrine's answer is that a belief which is load-bearing must not be removed until a replacement is in place, and that a replacement takes a generation to build, and that therefore the correct action is always, always to wait and prepare. And you can run that argument forever. It never expires. It's been running for eighty years. It's designed never to expire." She looked up. "And you've just told me that the thing it's spending is the only thing we can't make more of."

"Yes."

"Four hundred years."

"Four hundred certified. Bett's study says the air goes at six to nine hundred."

"Bett," said Camila, and then, "no. Don't tell me. I'd rather not have it." She wiped her face with the flat of her wrist, briskly, the way their mother had. "Sol. Listen. Whatever you're going to do — and you're going to do something, you've had the look since you came through the door — don't do it as a person. Do you understand me? Nadia went as a person. She went to a friend, with a case, and asked to be believed. Never do that. That's the one move the machine is perfect at."

"Then what?"

"I don't know that either." Camila laughed, wetly. "But I know what my office can't touch. It can't touch a work order. It can't touch a certification. It can't touch a stores ledger, obviously, or you'd never have got the number. We manage people, Sol. We're very good at people. Nobody in Programme has ever in my hearing discussed a piece of metal."

Sol sat back slowly.

"Say that again."

"Nobody in Programme has ever discussed a piece of metal."

"That was Ansel's idea," Sol said, half to herself. "That was the best idea any of us ever had, she said."

"Who's Ansel?"

"A man who went outside in Y69 to get something you could put in a person's hand." Sol stood, and took her harness off the back of the chair, and found her legs were unreliable. "Cami. What do you have to do now? Tonight, when I've gone. Tell me the truth and I won't hold it against you, but tell me, because I have to plan."

Camila looked at her for a long moment.

"Nothing," she said. "There's no obligation on a family conversation. There's no form." Her mouth twisted. "That's the whole trick, do you see? They never had to make us informers. They just made everything else so easy to file."

"And in the morning?"

"In the morning I have to certify eleven Half-Way procession routes and approve a verse for the Bell." Camila's voice cracked on the last word and she put her hand over her mouth, exactly as Bett had, and Sol thought: it's the same gesture, it's the ship's gesture, we've all been doing it for ninety years. "God help me. Six thousand two hundred days to a milestone that isn't a milestone. I'm supposed to have the procession approved by the eleventh."

"Then approve it."

"What?"

"Approve it. Approve everything. Do your job beautifully." Sol got the door open. "Be the last person anybody would ask about me."

"Sol — "

"Give me until the Bell," said Sol. "That's what I want. Nine days. Then I'll come and tell you what I'm doing before I do it, and you can decide then whether you're my sister or an officer of the Programme, and I'll accept either, and I mean that."

Camila stood in the light of her own kitchen with the good grow-window behind her and the folder of processions on the shelf.

"I'll want the arithmetic on Tico by then," she said.

"So will I."

Tico caught her at the door with the ship in both hands.

"You didn't say if the fraying's right."

Sol crouched. Up close the little orange fringe was very carefully done, each fibre teased out with a pin and set with a dot of glue, three or four hours of a child's evening, and it stuck forward off the Cap into the air like something burning.

"The Cap doesn't glow," she said.

He frowned. "The animation — "

"The animation's showing you energy, not light. It's a diagram." She turned the model over, gently, and touched the Cap with her thumbnail. "In the real thing it's cold. It's colder than anything you've ever touched, and it's grey, and it's rough like a bad weld, and it doesn't shine at all. That's what makes it good. It's just standing there taking it, forever, in the dark, where nobody's ever going to see it."

Tico considered this with enormous seriousness.

"That's better," he decided.

"Yes," said Sol. "That's what I think."

"Should I take it off?"

"No. Leave it. Make the next one grey." She stood up, and put her hand on the back of his head for a second, and got out before her face did anything.

She went forward that night.

Not for the rig — the rig was already recovered, the logger locked in a drawer under a box of witness clips with a false label on it. She went up through the three ladders and the long crawl where her inner ear filed its complaints, and through the pressure door with its hand-painted sign, into the cold that got into her teeth, and she stood in the vestibule for a while in front of the coupon rack with sixty numbered slots in it and thirty years of manufactured proof.

Then she knelt at the base of it and cleared the dust off the coin with her thumb.

COUNT THE PITS

A. F-S.

Four marks and a fifth across them. Ansel, dead at the rosette with a closed secondary. Idris, nodding at Bett Osei for sixteen years from a berth with a window bay. Hana, out the Frame 9 lock in the autumn. Bett, forty thousand tonnes of honest shielding built to a dishonest number. Nadia, who had said my grandchildren will see it.

Sol took out her scribe.

She had thought, all the way forward, that she would make the sixth mark, and had felt the weight of it coming, and it had seemed to her somewhere around the second ladder that this was exactly the trap: that the coin was the most humane object aboard the ship and also the most efficient, because it took every person who saw clearly and gave them somewhere quiet to put it. Five people in thirty years had found the truth and had been reduced, in the end, to a tally on a coin. The Consensus had not needed to guard that. It had never needed to guard anything. It only had to make sure that the alternative to acting was not nothing — that it was a small, dignified, private act of witness, which felt enough like courage that a person could live inside it for twenty-eight years and call it waiting.

She put the scribe to the deck coating beside the coin instead, and cut, in letters as small as she could make them, on the bare plate where the next person would have to lie down to read it:

COUNTED THEM. NOW COUNT THE FUEL. IT IS SPENT.

She looked at that for a while, breathing white in the beam of her head torch.

Then, underneath, because whoever came after would need to know that the door was still open somewhere and that they should not go alone through it:

BRING METAL. NOT WORDS.

She did not sign it. She did not add a mark. Six people had now looked into this and five of them had a place on the coin, and Sol Ibarra-Nakashima found that she wanted, very badly, to be uncountable.

On the way aft, in the long crawl where the spin gravity came back into her like a hand under her spine, she worked out that she needed three things and that none of them were secrets.

She needed a work order — a real one, filed, boring, with a cost code, for something Optical was entitled to do and Structures could not refuse.

She needed a licensed EVA escort, because nobody went outside alone, and the only people who went outside were the guild who drank on the Anniversary of Ablation and wore their pitting like decorations and would knock her down for saying the word rosette.

And she needed nine days.

The Bell was on the eleventh.

The Instrument Trust had four Standing Orders and nobody had read them since the Twenties, which was, Sol had come to understand, exactly the condition under which a weapon rusts quietly in a cupboard until somebody needs it.

She read all four in the shop at Frame 38 with the door open, drinking the terrible tea, on the second of the fifth month, nine days out from the Bell.

The first three were housekeeping: retention, chain of custody, the requirement that instrument logs be kept in full fidelity for the benefit of arrival. The fourth was different. The fourth had teeth, and it had teeth because the people who wrote it in Y13 had just watched a ship's whole reason for existing come apart, and they had wanted very badly for the instruments, at least, to be honest, even if nothing else could be.

STANDING ORDER 4 — CHARACTERISATION OF OPTICAL PATH DEGRADATION.

4.1 An astrometric channel's calibration certificate rests upon the documented condition of its entire optical path, from detector to first surface.

4.2 Where the condition of any element of that path is undocumented, or is documented by a process which cannot be independently verified, the channel's certificate shall be SUSPENDED by the responsible grade, without reference to Navigation, until characterisation is complete.

4.3 No astrometric solution shall be published on the authority of a channel whose certificate is suspended.

4.4 A defect identified in one channel of a class shall be treated as a defect of the class until excluded by inspection of every member.

Sol read 4.2 eleven times.

Without reference to Navigation. Somebody had fought for those four words in a room in Y13, and had won, and had probably thought they were fighting about scattered light.

She put the tea down and got out a fresh work-order form, the paper one, because Optical still kept paper forms for outside work and because a paper form went into a physical file at Frame 38 and a scan into the system, which meant two copies in two custodies, and she was learning to think like that now, the way you think about redundancy in a pressure hull.

Then she sat for two hours and wrote the most careful thing she had ever written in her life.

The temptation was enormous. She wanted to put it all in. She wanted to write the Bow Cap is silent and the coupons are manufactured and we are travelling at one fortieth of book speed, and she understood with total clarity that if she wrote one of those sentences the document became a symptom, and the symptom had a category, and the category had a keyworker and a very kind young man who came three times a week.

So she wrote about a chamfer.

Every one of the twelve photometric channels looked out through a slit in the ablation armor: two hundred and forty millimetres by eighteen, cut through eleven centimetres of laminate, with a knife-edge at the outer surface, chamfered nought point two millimetres to a specification laid down before Departure. The chamfer was there for a reason. A sharp edge in a dust stream erodes; as it rounds, it stops occulting and starts scattering, throwing a haze of stray light into the field of view, raising the channel's noise floor and slowly, secularly, shifting its zero point. The Departure engineers had known this. They had budgeted for it. There was a curve in the Trust archive, drawn by a woman named Ekwueme in Y2, predicting the exact rate at which each aperture would degrade under the design dust flux, and it predicted that by Year 80 every channel of the class would have lost between four and six percent of its photometric zero point to edge rounding, and would require its first aperture reconditioning between Y77 and Y84.

The channels had lost nothing. Not one of them. Sol pulled all twelve zero-point histories, eighty years of them, and they were flat as a bench top, flat within the noise, flat with a flatness that no piece of hardware on this or any other ship had ever achieved.

She looked at those twelve flat lines for a long time, and thought about how many ways there were to be caught by the truth. You could be caught by a star that repeated itself. You could be caught by a silence at Spar 7, or by a crater floor at eight microns. Or you could be caught, ninety years later, by the fact that a dead woman in Y2 had drawn an honest curve, and nobody in the Consensus had ever thought to make the apertures pretend to wear out.

They had faked the sand. They had not faked its consequences. It was the mistake of people who had built a stage set and never once asked what would happen if a carpenter came in with a level.

So Sol wrote her fault report about that, and only that.

WORK ORDER WO-14C-0502-1. ORIGINATING GRADE: HULL OPTICAL & SENSING. ORIGINATOR: IBARRA-NAKASHIMA, M., 14C.

SUBJECT: Aperture edge condition, Photometric Channels 1–12 (class defect, SO4.4).

FAULT: Channel zero-point histories for all twelve members of the class show no secular drift attributable to aperture edge erosion over 80 years of exposure. Predicted drift (Ekwueme, Y2, Trust archive ref TA/OPT/0114) is 4–6% by Y80, with first reconditioning due Y77–Y84. Observed drift: 0.0% ± 0.3%.

ANALYSIS: Two explanations exist. Either (a) the cumulative ablation model on which the Cap's entire maintenance basis rests is wrong by more than an order of magnitude, in which case the ablation budget, the coupon record, and the plate rotation schedule require immediate revision; or (b) the apertures have been maintained, reconditioned, or replaced by a process which does not appear in any Optical or Structures record, in which case the optical path of every astrometric channel aboard is documented by an unverifiable process.

A third explanation, that the instruments are correct and the model is correct and the apertures have simply not eroded, requires the flux at the first surface to be a small fraction of design. The originator notes this without further comment, as flux is not an Optical matter.

She read that paragraph four times, took out the word small, put it back, and left it.

REQUIRED ACTION UNDER SO4.2: Calibration certificates of Channels 1–12 are hereby SUSPENDED pending external characterisation of aperture edge condition. Suspension effective 0600, 5/03/Y80.

REQUIRED ACTION UNDER SO4.4: External inspection of all twelve apertures by qualified optical grade, with metrology, photography at 12×, and recovery of one witness section of first-surface armor adjacent to Aperture 14 for laboratory measurement of specular reflectance and edge profile. Recovery volume: 60 × 60 × 6 mm. Cutting authority requested from Forward Structures.

SUPPORT REQUIRED: One (1) EVA, tethered, two-person minimum, Forward Structures escort, Rosette 3 vestibule egress. Estimated 4.5 suit-hours. Charge to ABL-4.

MARGIN: The originator has attempted to falsify this fault by three independent routes (detector-level gain audit; cross-channel differential photometry; recomputation of the Ekwueme model with worst-case assumptions on grain size distribution). The fault survives all three. Working notes attached, 31 pages, hand copy held at Frame 38.

She signed it, thumbed it, scanned it, filed the paper, and sat back, and her heart was going like a pump with air in it.

There it was. Not a story about the past. Not a moral question. A chamfer, a curve from Y2, and a request for sixty millimetres of metal.

Nowhere in four pages had she written we are not moving. She had written something better, which was: your own paperwork disagrees with itself, and I am entitled to go and look.

It was, she thought, standing up to stretch her back, the first honest document she had produced in nineteen years, and it had taken her nine days and an old woman in a chair by a wall of runner beans to learn how.

Naveen Duarte-Chatterjee, Optical & Sensing Grade V, had a berth-sized office at Frame 35 and the look of a man who had been in it since Y61. He signed things. That was the job at Grade V: you were the throat through which your grade's paperwork passed, and you had learned to swallow.

He read Sol's four pages with the flat attention of a man expecting a leave request, and stopped at the top of page two, and went back to page one, and read it again with his finger on the line.

"You've suspended the class," he said.

"Under 4.2."

"Twelve channels."

"It's a class defect. 4.4."

"Marisol." He took his glasses off. He was sixty-eight and had a laugh she'd heard twice. "Do you know what happens at 0600 tomorrow if this stands? Nav can't publish. There's no daily solution. There's a bulletin board in the Bowl with a number on it, and there won't be a number."

"There'll be a number," said Sol. "They'll publish it on the gyro and the old solution and call it a provisional. Nav's not stupid and they're not going to leave the board blank on a Tuesday. But they'll have to publish it as provisional, and the word provisional will have my work-order number next to it, and it'll sit there until somebody characterises twelve apertures."

"Which nobody's ever done."

"Which nobody's ever done, in eighty years, on the primary navigational sensors of a ship of nine thousand people, and I'd like you to hear how that sounds out loud." She kept her voice absolutely level. "Chief, I've been on Fourteen since I was twenty-two. I've swapped its head, its shunt, its preamp, and its whole cold chain. I have never once put an eye on its first surface. Nobody has. We've been certifying the optical path from the detector back and calling the front of it an act of faith."

Duarte-Chatterjee put his glasses on again and read page two, the paragraph about flux, and Sol watched him read it, and watched his eyes go along the line twice, and watched him decide not to see it. She would remember that: the small mercy of a tired man, and the exact shape of the way it worked.

"Structures will refuse," he said.

"Then they'll have to refuse in writing, and their refusal will go in the file next to a suspension I'm entitled to make, and the two documents will sit there together being embarrassing, and eventually somebody senior enough to be frightened of paper will make them stop."

"That's a strategy."

"It's a maintenance schedule," said Sol.

He signed it. Then he sat holding the pen and said, not unkindly, "You've had a shift and a half of sleep this week. Pim mentioned."

"Pim's a gossip."

"Pim's fond of you. So am I, in the way of a man who signs your leave." He put the pen down. "Go carefully with 4.2. It's a big axe for a small tree. If the apertures turn out to be fine, you'll have stopped the ship's clock for a fortnight over a chamfer, and Nav will remember it for twenty years."

"If the apertures turn out to be fine," said Sol, "I'll have been wrong about the least important thing I've been wrong about this month."

She got out before he could ask her what she meant.

The query came at 0511 the next morning, while she was eating a bun in the Frame 33 alcove and watching the board tick over to DAYS TO HALF-WAY, 6,201.

It was polite. That was the first thing about it. It arrived on the public board under her guest token with a little chime, and it read:

INSTRUMENT TRUST — CHANNEL INTEGRITY QUERY. REF 14/0212-G.

Ch.14 logged a −4.02% gain excursion at 0247, 4/12/Y80, with a 19-minute out-of-solution interval, logged as detector burn-in. Excursion not present in the burn-in envelope for this head type. Please confirm intent, and confirm channel restored to nominal gain. Nav has interpolated across the gap; no impact to the solution. No further action if intentional. Thank you for the good work on that cryo-shunt — the noise floor is the best it has been since Y71.

J. VANCE-OYELARAN, ASTROMETRY II.

Sol read it three times with the bun going cold in her hand.

Thank you for the good work.

She had detuned the gain by four percent in the dark, alone, behind Frame 40, in a moment she had believed to be entirely private, and it had been logged, and a stranger in Nav had looked at it four weeks later and written to her kindly about her noise floor.

There was no room full of men with a list. There was a young astrometrist doing a monthly integrity sweep, exactly as the schedule required, exactly as they had been trained, and being nice about it.

And the name.

Vance-Oyelaran. Idris Vance-Oyelaran, astrometry, sharp as a scribe, who had put his mark on the coin in Y63 and gone to the Register and got a Grade III he hadn't sat for and a berth with a window bay, and had nodded at Bett Osei for sixteen years without speaking.

There were, Sol thought, perhaps thirty family names in Nav. It meant nothing. It meant a grandchild or a great-niece, a person who had grown up in a berth with a window bay and had probably been told her grandfather was a great man, and who was now nineteen or twenty-six or thirty and doing sweeps in the third week of the month and being pleasant to hull techs.

She wrote back, on the public board, in the open, with the tamarind vendor five metres away:

Intentional. Gain excursion was a cache-integrity test — I was checking whether the head could be replaying buffered counts. It can't; it came back clean. Channel restored to nominal same shift. Full method in WO-14C-0502-1, page 3, if you want it. Thanks for the sweep. — M.I-N., 14C.

She looked at the words cache-integrity test sitting there in the light of a public terminal on a Tuesday, and thought: that is completely true, and it will read to her as tedious, and it is also the exact centre of the thing, and I have just handed it to Nav in a sentence.

That was the game, then. Not hiding. You could not hide on a ship two kilometres long with nine thousand people in it and a log on everything. You could only be boring, and be boring in writing, and let the boring paper accumulate in custodies until it became a structure somebody had to walk around.

The reply came in ninety seconds.

I want it. — J.V-O.

Forward Structures kept its shop at Frame 8, past the last of the Ribs, where the deck curved and the spin gravity had gone thin enough that people walked with a long, low, loping stride that Sol had never mastered. You could tell a Structures tech in the Bowl by the way they came down a ramp.

The shop was enormous and smelled of hot metal and cutting fluid and the particular cold-iron scent of the forward volumes, and it was, unlike every other space aboard, ugly on purpose. No grow-wall. No amber runners. Bare plate, hard white light, and along the whole aft bulkhead the guild's wall: a hundred and ten years of erosion charts, hand-plotted in ink on paper, one sheet per year, going up the wall in a column like a tally, each sheet initialled by the chief of the day. The sheets nearest the deck had gone the colour of weak tea and the ink on them was brown; the sheets at the top, where a person needed the rolling ladder, were still white. Sol had been in this shop eleven times in nineteen years and had always taken the wall for decoration, the way you take a mural for decoration, and she stood in front of it now for four minutes before anybody spoke to her, and read it the way she should have read it the first time.

Each sheet was a plot. Horizontal axis, days since the last swap; vertical axis, mean mass loss per coupon in milligrams; a dozen points per sheet, hand-plotted with a fine nib, and a fitted line drawn through them with a straightedge. The oldest sheets were from the yards, Y-27, Y-26, before there was a ship to speak of, when somebody had been erosion-testing laminate samples in a dust gun in Mars orbit and plotting the results in ink because that was how you did it then. Then Departure. Then eighty years of a column climbing the wall.

The points scattered. That was the thing about the early sheets: the points scattered the way real measurements scatter, above and below the line, because a coupon is a small object and dust is a coarse business and a micrometer is operated by a human being with a cold hand. Y30's sheet had one point so far off the trend that the chief of the day had drawn a little circle around it and written bad seat? beside it in the margin, and Sol felt an unreasonable affection for that woman, whoever she was, dead sixty years, arguing with her own data in brown ink.

The scatter went on up the wall. Y40. Y50. Y60. Y68.

At Y69 the scatter stopped.

It did not narrow. It stopped. From Y70 onward the points lay on the fitted line like beads on a wire — twelve points a sheet, ten years, twenty years, all of them within a hair of the straightedge, and the hand that plotted them was a good clear draughtsman's hand and had never once had cause to write bad seat? in the margin, because the numbers it received did not have seats. They had a specification.

Sol was still looking at it when the chief said, "Optical," from about a metre behind her left shoulder, in the tone of a woman naming a stain.

"Chief."

"You've been standing at my wall for five minutes."

"It's a good wall."

"It's the only honest thing in this shop, which makes it the only honest thing forward of Frame twelve." Chief Adaeze Ekwueme-Strand came around into her eyeline: seventy-one, a head shorter than Sol, forearms like bundled cable, a burn scar across the back of her right hand in the shape of a coin. She had a paper in her other hand and Sol did not need to be told which paper. "You want to cut my armor."

"Sixty millimetres square. Six deep. Off the first surface, adjacent to Aperture Fourteen."

"You want to cut my armor."

"Yes."

The shop had gone quiet in the way shops go quiet — nobody stopped working, everybody stopped talking. There were nine or ten of them in there, on the benches and up on the gantry over the plate stock, and Sol could feel the attention arriving on the back of her neck like a change in the air handling.

"Come," said the chief, and did not wait.

Her office had no door, just a bay off the main floor with a plotting table and a stool and, on the wall, a photograph. Sol saw it and had to make herself look away and then made herself look back, because looking away was what she'd been trained to do and she was finished with that. A group of eleven in suit liners, arms across each other's shoulders, in front of the Frame 9 lock, hair flat with sweat, grinning like idiots. Y69, said the caption. ROSETTE 3 — SPRING SWAP — 41ST CONSECUTIVE.

"Sit," said the chief.

Sol sat.

The chief put the work order on the plotting table and smoothed it with the flat of her scarred hand and did not look at it.

"Nineteen years you've had Fourteen," she said. "You brought us coffee at the Ablation. Twice. You were the only Optical who came the year the lift was out and you came up the ladders with it, and it was cold, and we drank it anyway, and Merced said afterwards that you'd carried three litres of cold coffee up eleven decks for people who called you a name to your face, and that was either character or brain damage."

"It was character," said Sol. "It's improved since."

"Mm." The chief still had not looked at the paper. "So I'm going to do you the courtesy of the short version. I can't give you cutting authority on the first surface. Not sixty millimetres, not six, not one. The Cap is a stack of sacrificial plates and the whole basis of the ablation budget is that they wear as a plane — you take a bite out of a plane, you get an edge, and an edge in a dust stream is a knife that cuts backward into the plate you left. That's not policy. That's the physics we've been living inside for eighty years. I'd refuse the Bridge on this. I'd refuse my own mother, and she's in the Grove."

"I know," said Sol. "That's why I asked for the smallest square that would still give me a specular measurement, and why I asked for it adjacent to Fourteen, where there's already a slit, and where the edge I'd make would sit inside the shadow the aperture edge is already throwing. I ran the geometry. If the flux is anywhere near design, my square costs you eleven grams a year off the plate behind it, and the plate behind it is Class B and due out in Y96 anyway."

The chief's eyes came up.

"You did the geometry."

"I've been at this nine days, Chief. I did all of it. I did it because I knew you'd say plane and I wanted to have an answer that wasn't please."

Something moved in the older woman's face, quick, and was put away. She picked up the paper at last and read it in silence, all four pages, taking her time. When she got to page two she stopped and read the flux paragraph twice, exactly as Duarte-Chatterjee had, and unlike Duarte-Chatterjee she did not go on. She put her finger on it. She kept her finger on it for perhaps six seconds.

Then she said: "The apertures are flat because we rotate the plates."

"No, you don't."

"Optical — "

"Aperture plates are Class A." Sol had it ready; she had had it ready for four days. "Class A is never rotated, because you can't re-cut a two-hundred-and-forty by eighteen slit through eleven centimetres of laminate in situ and hold a nought-point-two chamfer to spec with a hand tool in a suit. That's your own standing instruction, ABL-STD-3, revision six, and your own note in the margin of revision four says do not attempt outside, we will lose the channel. Your great-grandmother's initials are on revision one."

The chief sat down on the stool.

"Great-aunt," she said.

"Fola Ekwueme."

"Folasade. She drew that curve you're citing in the yards, in a room with a window, looking at Mars." The chief's voice had gone flat and careful. "And she wrote to her sister that the front of the ship was the only part of it she was afraid of, and her sister kept the letter, and it's in a box in my berth, and I've read it about nine hundred times. So don't tell me about my great-aunt's initials, I know exactly where they are."

"Then you know her curve says four to six percent by Y80."

"I know."

"And that we've got nothing. Twelve channels. Eighty years. Nothing."

"I know," said the chief.

The shop noise went on outside the bay: a grinder somewhere, a hoist, somebody laughing about something with two syllables in it. The photograph of eleven grinning people in suit liners hung on the wall between them.

"How long have you known?" Sol asked.

"I don't know anything." The chief said it fast, and heard herself, and stopped, and then said, in a completely different voice, one that made Sol's arms cold: "Eleven years."

Sol waited. It was the hardest thing she had ever done with her mouth.

"Y69 was the last time this guild went outside," said Chief Ekwueme-Strand.

"That's — no. There's an EVA every six months. Twice a year, Rosette 3, the coupon comes in and you rack it. I've been to the pre-checks."

"You've been to the pre-checks." The chief's mouth did something ugly. "You've been to the pre-checks, and you've stood in the vestibule while my techs ran a suit integrity board and a tether inspection and a comms check and signed a checklist eleven pages long, and then you've gone away, because Optical's part is done at that point, and it has never once occurred to you — why would it, it's not your grade — to stay and watch which lock opens."

"Chief."

"Ansel Ferreira-Sunquist went out at Rosette 3 in the seventh month of Y69 and did not come back," said the chief, "and I was thirty and I was on the board, and eleven weeks later there was a Trust safety finding, and the finding was that forward EVA was to be reorganised under a competent authority with continuous specialist practice, and the competent authority was designated as the Trust's own maintenance detachment, which is four men and a woman berthed at Frame Six, and my guild was designated support." She was not raising her voice. It was worse. "Support means we own the suits and the checklists and the tether racks and the training and the certification and the drills. We drill it. We drill it four times a year, we've never dropped a ticket, we are the best-trained body of people aboard this ship at a thing we are not permitted to do. And twice a year the Frame Six detachment egresses through the Frame 9 lock with our suits and our checklist and our blessing, and comes back in ninety minutes, and hands my duty tech a coupon in a numbered bag, and my duty tech carries it up to the vestibule and puts it in the slot and aligns it to the notch."

Sol looked at the wall of the bay and thought about the scatter stopping in Y69, twelve points a sheet, dead on the straightedge, in a good clear draughtsman's hand.

"Ninety minutes," she said.

"Ninety minutes."

"It's forty minutes out to Rosette 3 from the Frame 9 lock. There and back is eighty."

"Yes."

"They're not going to the rosette."

"I don't know where they're going. I've never asked. I've never — " The chief pressed the heel of her scarred hand against her eye socket, hard, once. "Do you know what I've done with eleven years, Optical? I have run the finest EVA training programme in the history of this vessel. My people have a hundred percent ticket currency. There isn't a suit in that rack that hasn't been stripped and rebuilt in the last two years. We drink on the Anniversary of Ablation and I make the toast, and the toast is to the plates, which take it for us, and every single year I stand there with a cup in my hand and I know that I do not know what is on the front of this ship, and every year I decide that the alternative is to stand up in front of my guild and tell them their entire profession has been a support function for a decade and that we have racked a hundred and forty coupons we did not pull."

"A hundred and thirty-two," said Sol. "Eleven years, twice a year, is twenty-two. Plus the thirty years in the rack. Plus Archive."

"Thank you," said the chief, with terrible dryness. "I appreciate the metrology."

Sol found she had put both hands on the plotting table.

"Chief. Did anybody ever take a loupe to one?"

"To a coupon?"

"To a coupon."

"Why in God's name would we? We weigh them." The chief's hands were still. "We weigh them on a balance my great-aunt's shop built and we plot the mass loss and we've done it since before the ship moved. That's the measurement. That's the measurement. The loupe is for the plate faces on a real inspection, when you're looking for crack initiation." A pause; a long one. "Should I have?"

"The pits stop at eight microns," said Sol. "All of them. Hard floor, nothing below it, and there's a raised lip around every crater, identical, like a rivet set by a machine. Under twelve magnifications it looks like a screen print. I put my glass on one nine days ago in the vestibule and I have not slept properly since."

Chief Adaeze Ekwueme-Strand sat on a stool in her own bay, in her own shop, with her own great-aunt's hand on the wall behind her, and did not move for a long time.

"And the mass loss?" she said at last, hoarse.

"Whoever runs the machine is good," said Sol. "The mass loss will be exactly right. It has to be, or the wall would have caught them. They shoot it to the mass and they don't look below eight microns because nobody has ever looked below eight microns except a twenty-two-year-old apprentice with a loupe her teacher put in her hand." She heard her own voice go quiet. "Chief, the scatter stops in Y69. On your wall. Anyone who ever loved that wall could see it from across the room. I saw it in four minutes."

The chief turned and looked at the column of sheets through the open side of the bay, the eighty years of it, brown ink to black.

"Merced said it," she said. "Y74, or thereabouts. She said, the numbers have got very well-behaved, Chief. And I said measurement practice had improved." She laughed, one syllable, without any humour in it whatsoever. "Measurement practice had improved. She was nineteen. She's on the gantry now, she's got two kids, she's the best hand I have and she'll be chief when I go."

"Chief — "

"I'm not signing your cutting authority."

Sol had known it was coming and it went into her anyway, low down, like cold water.

"Why."

"Because I can't, and because you don't need it, and because if you make me refuse in writing I will have to write the reason, and the reason will be four sentences long, and those four sentences will be the end of my guild." The chief stood up. "Sit still, I'm not finished. You came here today with a plan and the plan was to get me to say no in a file so that your no and their no could sit together being embarrassing until somebody frightened made them stop. That's a good plan. It's a very good plan for a woman from Optical who has spent nine days learning how paper works." She took the work order and held it up. "It's also a plan that takes four years, and I've read your page one, and I've read your page two, and unlike your Grade V I read the paragraph about flux with my eyes open. You don't have four years, do you."

"No."

"Say why."

"Because every year we wait is a year off the front of the only plan that could work," said Sol, "and because on the eleventh of this month, at 0630, four hundred and six kilos of reaction mass is going out of a nozzle so that nine thousand people can feel it in their feet, and it's the last of it, or near enough, and my sister signs for it."

The chief looked at her.

"You're the one from the Bowl," she said. "Frame thirty-three. Thursday. You said you people out loud in front of a tamarind stand."

"How do you know that?"

"Optical," said the chief, "there are nine thousand of us in a tube." She put the paper down. "MERCED."

The name went out of the bay and across the shop floor like a dropped tool. The grinder stopped. Somewhere above, on the gantry over the plate stock, a voice said, "Chief," in the resigned tone of a person who has been listening for six minutes.

"Not you. Get me Teo."

Teodoro Amaral-Kwan was thirty-eight years old, narrow, quick-moving, with a shaved head and a suit-liner burn on his throat that had gone silver with age, and he came into the bay wiping his hands and stopped when he saw Sol.

"Chief."

"Ticket currency."

"Current. Sixty-one days on the wet drill, ninety on the board." He said it the way you say your own name. "Something happen?"

"Sit down. No, stand, you'll want to be standing." The chief folded her arms. "This is Ibarra-Nakashima, Optical, fourteen-C. She's suspended the certificates on all twelve astrometric channels under Standing Order Four and she's asked me for cutting authority on the first surface and a two-person tethered egress at Rosette 3, and she's going to tell you why in about four sentences, and I'm going to stand here and let her, because I have decided in the last ten minutes that I am too old to be careful and it turns out that is a physical sensation and I recommend it. Go on, Optical. Four sentences."

Sol stood up.

"The Bow Cap is silent," she said. "I put four pickups on the spars and integrated fifty-one hours and we are taking eleven grains a minute where we should be taking a storm, and the coupons in your rack are made by a machine at Frame Six, and Channel Fourteen has played me the same nineteen minutes of starlight on forty separate nights across twenty-five years because the astrometry is running off an archive. We're doing seven hundred and fifty kilometres a second. A fortieth of book. We've come two-tenths of a light-year in eighty years and Hale is four thousand six hundred years away, and the hull is certified for four hundred, and the air stops working somewhere around six hundred, and every one of those numbers is in the Trust archive in the ship's own hand."

Teo did not move at all.

"And I need," said Sol, "sixty millimetres of the front of this ship, in my hand, in this room, on that bench, because nobody in Programme has ever in their lives discussed a piece of metal."

The silence went on long enough that Sol heard the hoist chain settling on the shop floor.

"Say the last part again," said Teo.

"Nobody in Programme has ever discussed a piece of metal."

"No," he said. "The rate. Eleven grains a minute."

"Eleven a minute above threshold on four pickups, reconciled. Call it four thousand grains in fifty-one hours."

Teo sat down on the plotting table, which was not a thing you did in that shop, and put his hands on his knees, and Sol watched an entire interior structure come apart in a man's face without a single feature moving.

"I paid out his line," he said.

"I know," said the chief, quietly. "Teo."

"I was twenty-seven and I was on the tether and Ansel went out at Rosette 3 and I paid out his line and he was singing." Teo was talking to the middle of the room. "You could hear him breathing on the loop and he was going da-dum, da-dum to himself, some rhythm, he always did that when he worked, and he got to the rosette and he said — he said, Teo, I'm going to be a while, and I said the tender's line, I said you've got two hours forty, and then he said something I've never told anybody in eleven years, because it didn't mean anything, and if you tell people a thing that doesn't mean anything they build something out of it and then they're kind to you about it."

"What did he say?" said Sol.

"He said, there's no dust on it." Teo's hands were shaking exactly the way Camila's had, the fine tremor, noticed with mild surprise. "That's all. Teo, there's no dust on it. And I said say again, and he said nothing, and forty seconds later his primary was reading iced and I was calling the board and the board was calling the lock and it took us fourteen minutes to get a second man in a suit and it was already — "

He stopped.

"And then in Y70 a very polite man from Frame Six came and took our lock," he said. "And I have stood on that board twenty-two times since and watched them go out with my suits, and every single time, for eleven years, I have thought about there's no dust on it, and every single time I have decided it was a man with a fault in his regulator getting confused, because that is what a hypoxic man sounds like, that is exactly, precisely what a hypoxic man sounds like, and it is also what a man sounds like who has just looked at something."

Nobody said anything.

"I'll take you out," said Teo.

"Teo," said the chief.

"Chief, I'll take her out."

"You will not, because you will be stopped at the lock by a Trust detachment with a safety finding, and then you will be a P-7 and she will be a P-7 and I will be a chief who cannot account for two of her people, and we will have achieved nothing, and there will not be a seventh." The chief turned. "Optical. You said Frame Six twice. Say what you actually want. Not the metal. You've been playing me for twenty minutes and you've done it well and I'd like the last card face up on my own table, if you don't mind."

Sol had not known she had it until it was in her mouth.

"They egress for ninety minutes," she said. "Forty out, forty back, ten to work. They're not going to Rosette 3, and they're not going anywhere for ten minutes' work in a suit, which means they're going somewhere close, and something close is either the rosette itself or the aperture line, and I don't think they're loading coupons on the plates. I think there's a hatch."

"There's no hatch forward of Frame 4," said Teo. "I've had the drawings since I was fifteen."

"There's no hatch on the drawings you have," said Sol. "Chief. Who holds the as-builts?"

The chief of Forward Structures stood very still for a moment. Then she crossed the bay, and knelt, and pulled a flat steel case out from under her own plotting table — a case with a hasp and a paper label gone amber, the kind of object that has been under a table so long it has become part of the geology.

"My great-aunt's shop built the Cap," she said. "The Trust holds the maintenance set. The guild holds the fabrication set, because you cannot make a plate to a drawing you don't have, and nobody has ever taken them off me because nobody has ever wanted to make another C

— because nobody has ever wanted to make another Cap."

She put the case on the plotting table and opened the hasp with her thumb, and the smell that came out of it was a smell Sol had never encountered in her life and recognised instantly: linen, and old glue, and a mineral dryness, the smell of a room on a planet.

The sheets were enormous. Linen-backed, folded in eighths, drawn in ink at a table by people with sleeves rolled, and along the bottom of each one a title block in a hand so clean it looked printed until you saw where the nib had caught.

ANABASIS — BOW CAP ASSEMBLY — FABRICATION SET — EKWUEME & DAUGHTERS, FAB SHED 3, PHOBOS YARD.

The chief unfolded three of them before she found the one she wanted. She did it carefully, with her scarred hand flat, smoothing along the fold lines outward, the way you handle something that has already survived longer than you will.

"Sheet nine," she said. "Instrument fit-out."

Sol came around the table.

The Cap in section: the stack of sacrificial plates in hatched layers, the spar cage behind them, the twelve slits marching around the circumference like the ports of an old gun deck. And between the innermost plate and the spar cage, drawn in a thin line and shaded with a legend she had never seen on any drawing in nineteen years, a space.

A long, low, curving void, one point eight metres from deck to head, running the whole ring, with handrails, with lighting bosses, with a grated walkway and twelve numbered stations.

INSTRUMENT GALLERY. PROVIDED FOR ALIGNMENT AND CLOSE-OUT OF APERTURES 1–12. CLOSE OUT ACCESS 5-A AFTER FINAL ALIGNMENT: 8 MM PLATE, CONTINUOUS WELD, GRIND FLUSH.

Teo made a sound.

"That's foam," he said. "That's foam-filled. That's on the maintenance set as a void, foam-filled, Class D, no access, do not penetrate. I've had that drawing on my slate since I was fifteen years old."

"It is on the maintenance set as a void, foam-filled," said the chief. Her voice had gone strange and slow. "I have had that drawing since I was fifteen years old also. My great-aunt built a walkway forty metres long with handrails and lighting bosses and twelve stations for the fit-out, and then it was closed out and the Trust drew it as foam."

"The Trust curates the maintenance set," said Sol.

"Yes."

"Chief. When?"

"When what?"

"When did the maintenance set start saying foam?"

The chief looked at her, and then went and got a second case out from under the bench, a newer one, and pulled up the maintenance drawing on her slate beside it, and read the revision block aloud without any inflection at all.

"Sheet nine. Revision one, Y-1, instrument gallery, access 5-A, closed out. Revision two, Y13. Void, foam-filled, Class D. No access required. Do not penetrate." She put the slate face down. "Revised by TA/REG. Registrar of Instruments."

Nobody spoke for a while. Out on the shop floor somebody dropped something small and swore at it in a bored voice.

"Y13," said Sol. "Two years after the vote. Same year as the first annex of Continuity."

"What vote?" said Teo.

"Later." The chief was already unfolding sheet nine further, out past the section, to the elevation. "Here. 5-A. Frame 5, between spar six and spar seven, port of the axis. Eight hundred by six hundred, eight mil, continuous weld, ground flush." She looked up at Teo. "Teo. What's on that plate now?"

Teo did not have to think about it.

"Fire main clamp," he said. "There's a bracket for the number two forward fire main, it's bolted through into the plate, and the plate's painted the same grey as everything else, and there's a stencil on it that says F-MAIN 2 SUPPORT DO NOT REMOVE, and I have put my hand on that clamp about four hundred times going up to the vestibule because it's the only thing to hold in that stretch when the spin's thin." He wiped his mouth. "It's a handhold. We use it as a handhold. There's a shine on it where our gloves have been."

"And it's never been opened," said Sol.

"It's never been opened," said the chief. "That's the whole point, don't you see, that's the — " She stopped, and put both hands flat on her great-aunt's drawing, and Sol watched the guild chief of Forward Structures work out, in about four seconds, what it had taken Sol nine days to assemble. "They came in from outside. In Y13 they didn't need 5-A, they had suits and a whole ring of plate to cut, and they cut themselves a hatch somewhere out on the face where nobody but the coupon crew would ever be, and they've been going in and out of it twice a year for sixty-seven years, and 5-A has sat here under a fire main clamp with a yard weld on it since before this ship moved."

"Which means nobody watches it," said Sol.

"Which means nobody watches it, because there is nothing on the other side of it, because it's foam."

Teo had gone the colour of the plate stock.

"Rosette 3," he said. "Chief. Where's Rosette 3 relative to the aperture line?"

The chief walked her fingers across the elevation, from the numbered rosette pads out on the face inward, and stopped.

"Aperture fourteen is Channel Fourteen's slit," she said. "The numbering's an old Optical thing, don't ask. It's the fourth slit round from the pad." She measured with the flat of two fingers, twice, and then said it as a fact and not as a discovery, which was how Sol knew she had already known and had spent eleven years not knowing it. "Six metres. Rosette 3 is six metres from the slit line."

"He said there's no dust on it," said Teo.

"He got to the rosette and he looked six metres to his left," said Sol, "and he saw a hatch that isn't on any drawing he'd ever been given, and he had about forty seconds."

The grinder started up again out on the floor. Somewhere above them, on the gantry, Merced was standing very still with a plate hook in her hand, and Sol saw her, and Merced saw her seeing, and turned away and went back to work, which was, Sol understood, a decision, and possibly a kindness, and possibly the beginning of the end of all of them.

"I'm not signing cutting authority for the first surface," said Chief Ekwueme-Strand.

"I know."

"I'm going to write a work order for a weld integrity inspection of an eighty-one-year-old unopened yard closeout at Frame 5," she said, "because that is a completely reasonable thing for a Structures chief to do in the ninth decade of a hull's life, and because there is a standing recommendation from my own guild dated Y44 that original yard welds in the forward volumes be sampled for embrittlement, and it has never been actioned, because there was never any reason to open anything." She folded the drawing along its own creases, outward from the centre, with her scarred hand. "And you are going to be there in an Optical capacity, characterising the optical path from the detector to the first surface, which you are entitled and required to do under a Standing Order written by frightened people in Y13 who wanted at least the instruments to be honest."

Sol found that her eyes had filled, which was inconvenient.

"That's four sentences," she said.

"It's two," said the chief. "Get out of my shop. Come back on the eighth at 0100 and bring nothing that needs a bus."

Jaiye Vance-Oyelaran came to Frame 38 at 2340 on the sixth, three hours before her shift, because the hand copy of the working notes could not leave the shop and she was, she said, not going to read thirty-one pages standing up.

She was twenty-six. She was small and neat and she came in wearing the pale Nav coverall that everybody aft of Frame 20 privately thought was ridiculous, and she stood in the doorway of the hull shop and looked at the wall of witness coupons in their labelled clips and said, "Are these all real?"

Sol had not expected that.

"Say again?"

"Sorry. Sorry, that came out — " Jae put her hand up. "I've been awake since the fourth. Are those the erosion coupons?"

"Those are optical witness coupons. Different thing. Same idea." Sol pushed the bad chair out with her foot. "Sit down. Tea's terrible."

"I'd like some."

She read for fifty minutes without saying anything, and she read the way people read who have been trained to find the error: back and forth, thumb keeping a place, a slate beside her that she used only for arithmetic, checking Sol's numbers by doing them again in a different order. Twice she stopped and sat back and looked at the ceiling for a while, and once she got up and walked to the far wall and stood with her back to it, exactly where Sol had stood on the first night, and looked at the terminal from across the room.

Sol let her. She had been on the other side of this and she knew that there was nothing to be done for anybody in the fourth hour.

At the end Jae squared the pages, and set them down, and said: "Page nineteen. Your reconciliation for double-counting across the four pickups. You've assumed the shock front arrives at the pickups sequentially with a fixed propagation velocity in the spar."

"Yes."

"It doesn't. Not below about four kilohertz. The spar's a waveguide, it's dispersive, the low-frequency content arrives later and you'll have counted some of it as second events." Jae rubbed her eyes with the back of her wrist. "It makes your grain count too high. By maybe fifteen percent. Which makes your velocity estimate too high. Which makes it worse."

Sol sat down on the bench.

"You did that in fifty minutes."

"I've spent four years doing timing on twelve channels of a dispersive medium," said Jae. "It's the only thing I'm good at." She looked at the pages. "Everything else holds. The gain audit holds, the archive matching holds, and the aperture argument is — " She stopped. "The aperture argument is the best piece of work I've ever read. I want you to know that I understand what it is. You've written four pages that say we are not moving without ever once saying it, and you've addressed them to the only office aboard that has to answer paper."

"Then you know why I filed it."

"I know why you filed it. I came to tell you what happened when it landed." Jae wrapped both hands around the terrible tea and did not drink it. "At 0602 on the fifth, Nav published the daily solution as provisional, with your work order number in the footnote, for the first time in the history of this vessel. Nobody in the Bowl noticed. The board says PROVISIONAL in five-millimetre type under a number in forty-millimetre type, and my chief has aged four years, and the Trust's Registrar sent a note down at 0710 asking whether the suspension was expected to affect the Half-Way scheduling assumptions."

"That's the first question they asked."

"That's the first question they asked."

"Not is it true."

"No." Jae's mouth was very flat. "And I want to be fair, because my chief is a decent man and he's frightened, and his question was different. His question was: can we characterise twelve apertures without going outside. And I said no, and he said find out, and that's why I'm here at midnight, and — " she breathed out — "and I'm here at midnight because of something else, which I would like to say badly and quickly and then not say again."

"Go on."

"There's a module in the stack called Ephemeris Conditioning." Jae set the mug down. "TA/NAV/0007. It runs last. It takes the raw astrometric solution — the eclipse epochs, the timing residuals, the fits — and it applies a correction table and hands out the number that goes on the board. Everyone calls it the conditioning. It's been there since Y19. There is no source code for it in the archive. There's a compiled artifact and a two-page description and a signature block, and the description says it corrects for instrumental effects in the timing chain, and every astrometrist for eighty years has been trained on the sentence the conditioning corrects for instrumental effects in the timing chain, and I have said that sentence out loud to apprentices."

"And?"

"And in Y79, month four, I ran a bootstrap on the twelve channels to get a proper covariance for a paper I was writing about detector aging." Jae looked at her hands. "The twelve channels are not independent. They're supposed to be twelve eyes with twelve noise floors and twelve preamps and twelve cryo chains, and the residuals should scatter like twelve of anything scatters. They don't. Their covariance is degenerate. It's rank one." She looked up. "Do you know what rank one means?"

"It means there's one thing," said Sol.

"It means there's one source. Twelve channels, one source. I got a number out of that bootstrap that says the effective number of independent measurements in the entire astrometric stack of this ship is one point zero three." Jae laughed, one breath, ugly. "I filed it. Instrument Note 79/114. I said, verbatim, this is inconsistent with twelve physically separated instruments and I cannot explain it."

"What happened?"

"I got a commendation," said Jae. "A real one, on the board, my name in the Bowl for a week. Exemplary instrument vigilance. And a reassignment: off solution development, onto monthly integrity sweeps, which is a Grade II line with a Grade III supervisory allowance and my own bench and no committee work, and everybody told me I'd been given a gift, and I had been given a gift." She was crying now, without moving her face, the way Bett had. "And I have run those sweeps for a year and I have been good at them, and four weeks ago a hull tech at Frame 40 detuned a gain by four percent in the middle of the night and logged it as burn-in, and it was the first thing in a year that didn't fit, and I wrote to her, and she wrote back and said the words cache-integrity test on a public board, in the open, at breakfast."

"I know," said Sol.

"You knew what you were doing."

"I knew what I was doing," said Sol. "I'm sorry."

"Don't." Jae wiped her face with the flat of her wrist, briskly, and Sol thought: the ship's gesture, we all have it, every one of us. "Don't be sorry. Do you know what I did for eleven months after the commendation? "Do you know what I did for eleven months after the commendation? I stopped doing bootstraps." Jae picked the mug up again and this time drank from it and made a face that was almost normal. "Not because anyone told me to. Because I had a bench and a supervisory allowance and a thing I was good at, and every time I thought about Instrument Note 79/114 I felt tired in a way I have never felt about anything else in my life, and it was so much easier to run sweeps. That's the part nobody warns you about. It isn't fear. Fear would be something to fight. It's fatigue, arriving on schedule, exactly when you need to be brave, like it was requisitioned."

"Somebody told me that a week ago," said Sol. "She said: it's coming for you next week."

"Was she right?"

"It came on Tuesday."

Jae nodded slowly, as if a measurement had confirmed a model.

"Then I'll tell you what I've got and you can decide whether it's worth what it costs me," she said. "The conditioning module has an input I can't account for. It's a small table, forty-eight entries, and it's refreshed twice a year, and the refresh is filed under instrument maintenance as an ephemeris update, and its custody chain goes to the Trust's own maintenance detachment at Frame Six. Twice a year, Sol. Spring and autumn."

"With the coupon crew."

"They go out for ninety minutes twice a year and they come back and eleven days later the conditioning table is refreshed," said Jae. "I have never seen anybody carry a table anywhere. They don't have to. I looked at the file dates for the first time on the fifth, at about two in the morning, after I read your page two, and I sat in my bench bay and I thought: the table comes in from outside."

"It doesn't come in from outside," said Sol. "It comes in from the middle."

She got the folded print of sheet nine out of her coverall — the chief had let her trace it, on tissue, in pencil, in the shop, and had watched her do it and had not let the linen leave the bay — and she spread it on the bench under the yellowed lamp, and Jaiye Vance-Oyelaran of Astrometry looked at forty metres of walkway with handrails and lighting bosses and twelve numbered stations, drawn in ink by a woman on Phobos with a window and a view of Mars, and put both hands over her mouth.

"There's a gallery behind the apertures," she said.

"There's a gallery behind the apertures."

"Twelve stations." Jae's finger hovered a centimetre above the linen tracing, not touching it, the way you don't touch. "One at each slit."

"Twelve stations, one source," said Sol. "Your rank one. You found the same thing I found, from the inside out, a year before me, and you found it better, and you filed it in a language nobody had to answer."

"I filed it in the only language I had."

"So did Bett. So did all of us." Sol folded the tracing. "I'm going in at 0100 on the eighth. Frame 5, access 5-A, an eighty-one-year-old yard weld under a fire main clamp that everybody uses as a handhold. Structures is writing it as a weld embrittlement sample. I'm going as Optical, characterising the path from the detector to the first surface, which is a thing I am required to do."

Jae was quiet for a moment.

"You need me," she said.

"No."

"You need me, because if there's hardware at station fourteen you'll photograph it and measure it and you'll be right, and Nav will say the hull tech misunderstood the equipment, and one Grade V will say it to another Grade V and it will be true enough to survive a committee." Jae stood up. She was a head shorter than Sol and about half her mass and she had the particular steadiness of somebody who has stopped negotiating. "But if an astrometrist of record walks out of there and files an instrument note that says the twelve channels of this vessel are fed from a single synthetic source and I have stood next to the machine that does it — then it isn't a hull tech's misunderstanding. It's Nav's own paperwork disagreeing with itself. Which is the whole trick, isn't it. That's what your four pages do. I've just been reading a manual."

"They'll take your bench," said Sol.

"They'll take my conviction," said Jae. "I've read the taxonomy. Everybody in Nav has read the taxonomy; we make jokes about P-7 at the bench, that's how safe we feel." She picked up her slate and turned it off and put it face down on the bench, and left it there, which Sol understood was the entire content of her answer. "0100 on the eighth. What do I bring?"

"Nothing that needs a bus," said Sol. "And a loupe."

"I don't own a loupe."

"You'll own one by Thursday," said Sol.

The eighth, at 0100, in the cold at Frame 5.

There were four of them and one of them was a surprise.

Teo had the tool bag and a battery grinder with a fresh disc and the flat, unhurried manner of a man doing a job he had done four hundred times, which is a thing you cannot fake and cannot buy and which was, Sol thought, the only reason none of them were shaking. Jae had come in a hull-grade coverall two sizes too big, borrowed from somewhere, with her hair tied back and a loupe on a lanyard around her neck, still in its wrapper.

And Merced Ekwueme-Strand — thirty, two children, the best hand in the shop and chief in eleven years if there was a shop — was standing at the bottom of the ladder with a plate hook over her shoulder and a fire watch bottle on a strap, and she said, before anybody could speak: "Chief's not coming. Chief's in her bay at Frame 8 doing the paperwork with the door open and the lights on so that anybody who wants her knows exactly where she is, and she said to tell you that's not cowardice, that's a witness."

"I know what it is," said Sol.

"I know you know. She made me say it anyway." Merced looked up the ladder into the dark. "Hot work in a low-flow volume needs a fire watch and a second-person attendance. That's real. That's in the standing instruction and I've signed it, and if anybody comes I'm the reason this is legal, and if nobody comes I'm the reason it's safe." A pause. "And my mother's great-aunt drew that walkway. I've been in this guild since I was fifteen and I found out four days ago that I've been racking screen prints. So."

"Merced," said Teo.

"Don't. Go up."

The stretch between Frame 4 and Frame 5 was the coldest place Sol had ever put her hands. The spin gravity was down to a suggestion; you moved by pulling, and the metal took the heat out of your palms through the gloves in about nine seconds, and the only thing to hold in the last four metres was the clamp.

It was exactly as Teo had described. A cast bracket, bolted through into the plate, painted the same battleship grey as the whole forward volume, with a stencil in white letters gone chalky with age:

F-MAIN 2 SUPPORT — DO NOT REMOVE

And on the upper flange, a broad, soft shine, the colour of a worn coin, where sixty years of gloves had polished the paint down to metal.

Sol put her hand on it and felt the shine and thought about how many hands. Ansel's. Teo's, four hundred times. Bett's, forty-one times going out. A hundred and thirty-two coupons had come past this handhold in a numbered bag. Everybody who had ever gone forward on this ship had steadied themselves, for one second, on the door.

"Right," said Teo. "Optical, get behind me and stay behind me. Jae — Nav — you're going to hold the light and you're going to hold it where I say and not where you want to look. Merced?"

"Bottle's up. Flow's eleven percent. I've got the volume."

"Grinding a yard weld," said Teo, and it was not to them; it was the tender's line, the thing you say out loud so the recording of your own voice can be played back to a board later. "Frame five, plate five-A, weld sample under WO-8S-0507-3, Structures, Amaral-Kwan and Ekwueme-Strand attending, Optical in attendance under SO4.4. 0114."

The clamp came off in six minutes: four bolts, all four of them seized, all four of them yielding to heat from a pencil torch and a cheat bar, and it was so ordinary that Sol found herself watching for the flaw in it, some alarm, some voice. Nothing happened. The bracket came away in Teo's hands and he stowed it and its bolts in a bag and labelled the bag, because he was a professional and because the fire main would need to go back.

Behind it, under the paint, the weld.

It was beautiful. That was what stopped all four of them for a moment: a continuous fillet run, eight hundred by six hundred, laid down by somebody in a fabrication shed on Phobos with a steady hand and no reason to hurry, ground flush and then painted over and then painted over again by four generations of people who thought they were painting a wall.

"That's a yard hand," said Merced. "You can see the stops. Look — she stopped twice on the long side, and she restarted cold, look at the step. She was tired." She reached past Teo and put two fingers on it. "Eighty-one years."

"Merced."

"I'm looking at my — " Merced took her hand back. "Cut it."

The grinder made a noise that filled the whole forward volume and Sol's teeth, and threw a rooster tail of sparks that fell slowly in the thin gravity, drifting, going out one by one like something in a rendering, and Sol watched Jae watch them and thought: she's never seen sparks fall like that either. Nobody has. We are all children up here.

It took nineteen minutes. Teo cut three sides and left the fourth as a hinge, because he was cutting into a volume he had been told was full of structural foam and he intended to open it four centimetres and put a probe in before he opened it a metre. He was, in the strict sense, still doing an embrittlement sample; he had a coupon bag out, and he took his sample off the cut edge and bagged it and labelled it before he did anything else at all.

Then he put the cheat bar in and levered, and the plate bent back on its hinge with a groan that everybody felt in their sternum.

No foam.

Air came out. Not much: a soft, cold sigh, eighty-one years of nitrogen at slightly under vestibule pressure, and it smelled of nothing, absolutely nothing, the cleanest smell Sol had ever encountered, and behind it was a black rectangle eight hundred millimetres by six hundred.

Nobody said anything at all.

"Light," said Teo.

Jae put the light in.

The beam went in and did not stop. It went in and travelled, and travelled, and picked out a handrail — a real handrail, tubular, painted safety yellow, with the paint gone chalky and perfect — and beyond it a grated walkway with a nonslip pattern, and beyond that the curve, running away out of the beam into a dark that had a distance to it, forty metres of it, following the ring of the ship.

And at intervals along the outboard wall, on the wall that was the inner face of the ablation armor, a station: a shallow bay, a bracket, a small cabinet, and a cable run going aft, tidy, cleated every four hundred millimetres by somebody who cared about cleating.

"Oh," said Jae. It came out of her like something dropped.

Sol went in first. She had not planned that and did not remember deciding it; she was simply through, hands on the yellow rail, boots on the grating, and the grating rang under her like a struck pan, and she was standing in a place where no one had stood since a woman on Phobos had finished the alignment and gone home to a room with a window.

Except that was wrong, and she knew it was wrong before she had finished the thought, because the walkway had a path worn into it. Forty metres of nonslip diamond grating, chalky and dull under the rail and along the outboard side, and down the centre a strip a shoulder's width wide where the pattern had been polished flat and shiny by boots.

"They come in here," she said. "They come in here and they walk this."

"From where?" said Teo, coming through behind her, and then answered himself, turning his light aft along the ring: "There. Look."

Forty metres round, at the limit of the beam, a rectangle of newer metal in the outboard wall, with a hinge and a dog-latch and a suit-glove handle and a scuffed pad below it where people had put a knee.

"That's outside," said Teo. "That's the face. That's six metres from Rosette 3." His voice had gone very quiet. "That's what he saw."

Sol turned to the nearest station.

It was numbered, in stencil, on the outboard wall above the bay: 11. The next one along, aft, would be twelve, and forward the other way, ten. The numbering ran the wrong way round from Optical's, as the chief had said; she counted stations forward from eleven, walking, her boots ringing on the grating, four bays, and stopped at the one stencilled 14.

Aperture Fourteen. Channel Fourteen. Hers. Nineteen years.

The slit was there. It was exactly where sheet nine said it would be, two hundred and forty millimetres by eighteen, cut clean through eleven centimetres of laminate, and you could see the chamfer at the far end of it, the nought-point-two knife-edge that Folasade Ekwueme had specified before there was a ship, and it was as sharp as the day it was cut, because nothing had ever come through it.

Bolted over the inboard end of the slit was a blank.

A steel plate, four hundred by two hundred, gasketed, held by eight captive fasteners, with a small stencil on it in white: BLANK — DO NOT REMOVE WITHOUT AUTHORITY OF THE REGISTRAR OF INSTRUMENTS.

And on the bracket in front of it, aimed inboard down the optical axis at Channel Fourteen's cold little eye, a device.

It was not sinister. That was the thing Sol would try for the rest of her life to explain to people who had not seen it. It was a small grey box the size of a bread loaf, on an adjustable mount with three thumbscrews and a locking nut, with a fibre feed coming into the back of it from the cable run, and a filter wheel on the side, and a little glass window in the front the size of a thumbnail, and a rating plate.

PROJECTOR, ASTROMETRIC SIMULATION, 12-CH. MASTER SOURCE TA/NAV/SIM-1.
STATION 14 OF 12. ALIGN TO 0.4 ARCSEC. DO NOT ADJUST WITHOUT REFERENCE TO CONDITIONING TABLE.
PROPERTY OF THE INSTRUMENT TRUST. Y19.

Jae came up behind her and read it over her shoulder and made a small sound and sat down on the grating with her back against the yellow handrail and her light still on in her hand, pointed at nothing.

"Station fourteen of twelve," she said.

"There were only ever meant to be twelve," said Sol. "Somebody stencilled it wrong sixty-one years ago and nobody ever cared, because nobody who came in here needed to be told which station was which."

"One master source." Jae's voice was perfectly flat. "One source, twelve fibres, twelve projectors, twelve channels. Rank one." She laughed, once, at the deck plate. "I published a covariance of one point zero three and they gave me a bench."

Sol put her hand on the blank over the slit.

It was cold. Of course it was; the other side of it was the interstellar medium. Under her palm were eight captive fasteners, hand-tight, sixty-one years old, and behind them eighteen millimetres of slot and eleven centimetres of laminate and then fourteen light-years of vacuum with a scruffy little binary at the end of it, going around and around every four point three one days, throwing its fits, keeping no time for anybody, waiting to be seen by an instrument that had been looking at a slide of it since before her mother was born.

Eight fasteners. She could have done it in four minutes with the driver in her hip pocket.

She took her hand off the blank.

"Not tonight," she said, out loud, to herself, and Teo looked round.

"Say again?"

"Not tonight." Sol turned away from station fourteen, and found that her voice had come out steady, which surprised her, and that her hands were shaking, which did not. "If I open that slit tonight, Channel Fourteen starts reporting true starlight at 0230 on the eighth of the fifth month, and at 0600 the stack publishes a solution with one honest channel and eleven liars in it, and the stack throws out the outlier, because that is exactly what a good stack is built to do. And then there is a channel-integrity query, and a very kind person from Frame Six comes in through that hatch — " she pointed aft, at the rectangle of newer metal — "and puts the blank back on, and files it as a maintenance action, and we are all P-7 by Thursday and there is not a seventh person, ever, because we will have used up the only thing this place is worth."

"Which is what?" said Teo.

"Surprise," said Sol. "One time. This gallery is worth exactly one surprise and I am not spending it on a Tuesday."

She got out her camera, the film one, the ancient hull-survey Zenit-pattern box with no bus in it and no log and no clock, that Optical still kept because film did not need a certificate, and she began, methodically, station by station, to photograph the truth.

It took two hours and eleven minutes. Twelve stations, twelve projectors, twelve blanks with the Registrar's stencil, twelve fibre feeds going aft into a cable run that gathered, at the aft end of the gallery, into a single trunk the thickness of her wrist, and Jae followed her the whole way with the loupe out of its wrapper at last, reading rating plates aloud in a small clear voice for the record, adding, twice, "and the alignment nut has been adjusted; there's witness paint cracked on it," which was the single most damning sentence anyone said all night and which she said the way you read out a part number.

At the aft end, past station twelve, where the trunk went through the pressure boundary into the ship, there was a nail in the wall.

An actual nail — a stub of welding rod, welded to the wall at a slight droop, and hanging on it by a loop of lanyard cord, a book.

It was a hardbound field notebook, the kind Stores had issued since Departure and still issued, with a laminate cover gone soft as cloth at the corners. Sol lifted it off the nail and opened it with her light in her teeth.

Two columns. A date. A signature. Nothing else. Page after page after page.

Y19/11 — alignment, all stations — R. Adeyemi-Løkke, TA/MD.
Y20/04 — table refresh, stations 3, 7 drift — R. Adeyemi-Løkke.
Y20/10 — table refresh — R. Adeyemi-Løkke.

Sixty-one years of it. Twice a year, spring and autumn, in eleven different hands, and every hand neat, because these were people who had been taught that a maintenance log is a legal document. Sol turned the pages with one finger. In Y34 a hand had noted fibre 9 chafe at cleat 22 — replaced, 400mm. In Y47 somebody had written station 5 mount nut galled, tapped out M6, noted for as-built. In Y58 there was a small triangle of dried adhesive stuck to a page and beside it, in pencil, gasket sample, stn 2, hardening. Ordinary. Diligent. The work of five generations of good technicians who were told a thing was a calibration rig and who kept it beautifully.

And at the end, in a rounder, younger hand:

Y80/04 — table refresh, all stations, no drift. Alignment checked stn 4, 9. K. Odeleye-Vance, TA/MD.

And under it, in the same hand, the next line already written, the way a careful person writes the next line so the date is not forgotten:

Y80/05/11 — 0630 — TRIM WINDOW — supplementary refresh + stn 14 gasket. K. O-V.

Sol read it three times. Then she read it out loud, because Jae was four metres away and Teo was six and both of them had stopped moving.

"The eleventh," said Jae. "At 0630."

"During the burn," said Teo. "During the Trim." He came down the walkway fast, hand over hand on the rail. "That's why it's twice a year, that's — Optical, listen, the Trim's nine seconds of thrust on a two-kilometre spindle, the whole forward structure rings like a bell for about four minutes afterwards, you can't do fine work in here through it and you can't hear anything anywhere near it. Nobody logs a vibration event during the Trim because the Trim is the event. You could cut plate up here at 0630 on the eleventh and there isn't an accelerometer aboard that would notice."

"They come in under the noise," said Sol.

"Twice a year, on the days when the whole ship is having a feeling." Jae's voice cracked and she let it. "God. That's what the observance line in the ledger is. That's not just morale. It's cover."

"No," said Sol. She was still holding the book. "No, I don't think it is. I think it's morale, and I think it's aim, and I think it's also a maintenance window, and I think that's the worst part, because it means nobody ever had to decide anything. Somebody in Y19 noticed that the Bell burn was a convenient time to work forward, and put it on the schedule, and sixty-one years of decent people have kept the schedule, and the fact that nine thousand people put cups of water on their tables the night before is the load path." She closed the notebook. "It's not a conspiracy. It's a maintenance schedule. She told me that and I didn't understand it until now."

"Who did?"

"Somebody who's got a year left." Sol hung the book back on its nail, exactly as she had found it, the lanyard on the droop of the rod, and photographed it there, twice, at two exposures. "Teo. Can you close 5-A tonight so that it passes a walk-by, and open it again in three days in under ten minutes?"

Teo looked at the hinged plate, and at the paint, and at the fire main bracket in its labelled bag.

"Tack it in four places, grind the tacks proud, dust the line with grey, put the clamp back on with two bolts instead of four and thread the other two dry so they look seated," he said. "You'd have to lie on the deck with a light to see it. And nobody's lain on that deck in eighty years."

"Somebody has," said Sol. "That's the whole reason I'm here."

She stood for a moment at the aft end of the gallery, at the nail, with her light off, in the dark of a walkway forty metres long that had been drawn by a woman with a window on Phobos and closed out with a continuous weld and painted over four times by people who thought they were painting a wall, and she listened.

Under the hum of her own blood and the tick of contracting metal, through eleven centimetres of laminate and one steel blank, she could hear it: sparse, patient, unmistakable, the arrival of the real universe at a speed that meant nothing on this ship was true.

Tick.

And then, a long way off, another.

"Three days," she said. "The eleventh, at 0630, when the Bell rings and the whole ship stands still with its cups of water and feels itself move. That's when they come in, and that's when we'll be standing here, and that is when somebody from the Instrument Trust is going to walk through that hatch and find four people and a camera and a book with sixty-one years of his colleagues' signatures in it."

"And then what?" said Merced from the hatch, where she had been standing with the bottle for two hours and eleven minutes without once asking to come in.

Sol put her hand flat on the blank over Aperture Fourteen, one last time, feeling the cold of fourteen light-years come through into her palm.

"And then I take eight fasteners off," she said, "and we let the sky in, and we do it in front of a witness who cannot afterwards say he wasn't told."

She developed the film in the shop at Frame 38 on the afternoon of the eighth, with the door open.

Optical still kept the wet chemistry, four brown bottles in a cabinet with a stores code that had not been revised since Y38, because film did not require a certificate and because every twenty years or so a channel failed in a way that needed a record no bus had touched. Sol had done it perhaps eleven times in nineteen years. She did it now with the sink hood down and the amber safelight on and her hands going through the sequence her own teacher's hands had taught her, and when the first strip came out of the fix and she held it up to the light there was the gallery: forty metres of handrail, and the grated walkway with its polished centre strip, and station fourteen with its grey bread-loaf box on three thumbscrews.

She printed nine copies of each of the eleven best frames and hung them on the line over the bench like laundry, and while they dried she wrote captions on the backs in pencil — frame, station, exposure, time, attendance — and she thought about how absurdly strong a piece of paper was, in the right filing category, in the right hands.

Then she made three sets.

The first went into Chief Ekwueme-Strand's steel case at Frame 8, in among the fabrication drawings, because nobody had taken those off the guild in eighty years and nobody would think to start now. The second went to Jae, in a stores envelope labelled DETECTOR AGING — RAW PLATES — DO NOT BEND, to be filed at her own bench in Nav, four decks from the Registrar's office, in the middle of a stack of things that had been there for a year. The third set she put in a witness clip on her own wall, at the end of the row, between Y74 and Y75, where two generations of hull techs had hung small pieces of the ship's outside without anybody ever once looking at them.

The negatives she rolled into a film can and dropped into the drum in her berth, on top of a folded piece of paper with four numbers on it.

That was the eighth.

She went to Camila on the ninth, in the evening, as she had promised, and knew from the way the door opened that something had already happened.

"Tico's at Ruel's mother's," said Camila. "Sit down. Don't take your boots off, I want to be able to say you were here eleven minutes."

There was a folder on the fold-table. Not the procession folder. A thin one, grey, with a tab.

"Read it," said Camila.

P-7 REFERRAL — WELLBEING — INITIAL. Subject: IBARRA-NAKASHIMA, M., Hull Optical & Sensing IV, 14C, Frame 29. Referrer: PIMENTEL-OKAFOR, D., Dispatch II, Frame 36.

Concern raised in good faith. Subject has worked eleven consecutive third shifts including two unlogged forward transits. Not eating in mess. Declined social invitation twice, which is not like her. On 4/12 subject asked me to hold a channel out of solution and said "the head's perfect, that's the trouble," and laughed, and I have thought about it since. On 5/01 subject said, when I asked if she was all right, that the stars were repeating. I do not think she is unwell. I think she is tired and I think somebody should ask her a kind question before she is tired for another month. I would like it on record that she is the best tech on this shift and that I have said none of this to anyone else and won't.

Sol read it twice and put it down on the table very carefully, as if it might mark the surface.

"Pim," she said.

"Pim."

"He put in a sentence to protect me and it's the sentence that damns me. The stars are repeating." She heard her own voice come out level and hated it. "That's the P-7 diagnostic, isn't it. That's the exact phrase in the taxonomy."

"Category seven, presenting language, first bullet: reports that the ship's motion or schedule is not as stated; may cite instruments." Camila sat down opposite. "He's never read the taxonomy in his life. He'd be sick if he knew. He wrote three sentences and every one of them was love, Sol, and that's why the form works. It doesn't need informers. It only needs people who like you."

"How long do I have?"

"It came to me because of the family link — which is procedurally wrong, and I've flagged that it's wrong, which buys a delay and costs me a note in my own file. If I recuse, it goes to Frame 19 and a keyworker calls on you inside a day. If I sit on it, it auto-escalates at seventy-two hours from receipt." Camila's hands were flat on the table again, their mother's hands. "Receipt was 1140 on the eighth."

"The eleventh," said Sol. "Morning."

"Eleven-forty on the eleventh. And the Bell's at 0630." Camila laughed, one syllable, without humour. "So you've got until five hours after the burn, which I imagine is more than you need, because I've watched you build a fault report and you've never once needed the margin."

Sol sat back. The apartment smelled of onions and hot laminate and cheap paper.

"The Registrar's asked to see me tomorrow," she said.

"I know."

"How do you know?"

"Because I'm on the Half-Way Committee and so is she, and at 1600 today she asked me, in a corridor, in the pleasantest voice you have ever heard, whether my sister was well." Camila's face did not move. "That's how it happens. That's the whole apparatus. A pleasant question in a corridor from a woman who has never done a cruel thing in her life."

"What did you say?"

"I said you'd been overworking a channel for nineteen years and that it was a family failing." Camila's chin came up. "And then I went to the office and certified eleven procession routes and approved a verse for the Bell, exactly as you told me to, and I did it beautifully, and I have never felt so much like a piece of hardware in my life."

"Cami — "

"I did the arithmetic," said her sister.

Sol stopped.

"On Tico. You asked me to and I've done nothing else for nine days, and I want to give it to you properly, because it's the only thing I have to give and you'll need it more than you think." Camila pulled the grey folder towards her and squared it against the table edge, an office gesture, a woman steadying herself on procedure. "Here's the answer. You can't take it away."

"That's not an — "

"Let me finish. You can't take it away, and I don't mean you shouldn't, I mean it isn't a thing that can be removed. Belief isn't a fact in a person's head, Sol. It's structural. It's what he stands on when he gets up and goes to school and learns his frames. If you take Y197 out from under nine thousand people and put nothing in the hole, you don't get nine thousand people who know the truth. You get nine thousand people in freefall, and about six hundred of them will be dead within a year, and I can give you the Cerro's numbers if you want them, because they're in the doctrine appendix and I've read them so often I dream them." She looked up. "That's not Programme lying to you. That's the one honest page in forty."

"So what's the answer?"

"You have to trade it," said Camila. "You give him something else to stand on before you kick the floor out, and it has to be load-bearing, and there is exactly one thing in the universe that will bear that load, and you found it before I did and you didn't recognise it."

"Say it."

"Work," said Camila.

The word sat there in the warm room.

"Not truth. Not hope. Not a plan on a board with a date. Work." Camila's voice had gone quick and low, the way it went when she was solving something and did not want their mother to hear. "You told him the Cap doesn't glow. Do you remember what he did? He didn't cry, he didn't ask if we were all going to die, he asked should I take it off — and you said no, leave it, make the next one grey. And he'll make the next one grey, and he'll be fiercer about it than he was about the orange, because you gave him a correction and a job in the same breath." She spread her hands. "That's it. That's the whole method and it's yours, not mine. The ship cannot survive being told it's dying. It can absolutely survive being told there's a fault and here is the work order."

Sol found she could not speak for a moment.

"Four thousand six hundred years," she said at last. "That's not a work order. That's a wall."

"Then don't lead with the wall." Camila leaned in. "Lead with the chamfer. Sol, listen to me, because this is nine years of my grade and I'm handing it over: what you filed on the second is the most dangerous document ever produced aboard this vessel, and it is dangerous precisely because it is boring. A chamfer. A curve drawn by a dead woman in Y2. A request for sixty millimetres of metal. Nobody can be frightened of it and nobody can refuse it, and the moment it's answered honestly the whole thing comes down, not in a night, over years, in files, with engineers arguing about it — and an argument between engineers is a habitable story. It's the most habitable story there is. It's got a beginning and it's got tasks in it and nobody has to be a hero."

"That's your professional opinion."

"That's my professional opinion, and it's also the only thing that lets me look at my son." Camila's eyes were wet and perfectly steady. "Because if you do it your way — a fault, a work order, a certification, a piece of metal on a bench — then in twenty years Tico is a licensed tech arguing about the nitrogen cycle at a table with eleven other people, and that's a life, Sol. That's a better life than the one I was going to give him. It's got a real thing in it."

"And if I do it the other way?"

"If you stand up in the Bowl on the eleventh and tell nine thousand people that everything is over," said Camila, "then he's a boy whose aunt broke the world, and they will fix him, and they will be gentle, and by the time he's twenty he'll believe in Y197 the way Nadia Okonkwo-Reyes believed in it, and he'll say my grandchildren will see it, and he won't have grandchildren." She put her hand flat on the grey folder. "So. There's your arithmetic. Signed."

Sol reached over and put her hand on her sister's hand.

They sat like that for a while, which they had not done since their mother's committal.

"There's a thing I have to ask you for," said Sol, "and you're going to hate it, and I'd rather you heard it from me than felt it in your feet."

"You want the burn."

Sol nodded once.

"Nine seconds of thrust, and then the forward structure rings for four minutes, and there isn't an accelerometer aboard that would notice a person cutting plate at Frame 5." She kept her eyes on her sister's face. "That's not why they do it. They do it for aim and for morale and for the cups of water. But the Trust's maintenance detachment has used it as a work window twice a year for sixty-one years, and it's in their log in a girl's handwriting: 0630, trim window, supplementary refresh, station fourteen gasket. They come in under the noise. So will we."

Camila had gone very white.

"You're going to be standing in there," she said. "During my burn."

"Yes."

"With four hundred and six kilos going out of the number two nozzle because I signed the requisition on the fourth."

"Yes."

Camila got up. She went to the counter and stood with her back turned and her hands on the edge of it, and Sol watched her shoulders, and counted, and got to fourteen this time.

"I want two things," Camila said to the counter.

"Ask."

"The Bell stays." She turned around. "Not the Trim. The Trim's over, Sol; whatever happens on the eleventh, I will spend the rest of my career making sure nobody ever again burns reaction mass so that people can feel something, and I'll do it in requisitions and appendices and it will take me nine years, and it is the only promise I have that costs me anything. But the Bell stays. Six hundred and thirty, one note, ninety years. It doesn't spend anything and nine thousand people's chests loosen when they hear it, and if the truth arrives with its boot on that, then the truth is the thing that killed their grandmother's morning, and you will never get it back. Do you understand me? Don't let it come in as the enemy of the Bell."

"Agreed," said Sol. "Second thing."

"When it's done, I write what comes after." Camila's voice cracked and she went straight on through it. "You get the fault. You've earned the fault, it's yours, nobody could have done it but you. But I write the sentence that goes to nine thousand people, because you will write it like an engineer and it will be true and it will kill four hundred of them, and I know how to build a thing a person can stand on. That's my grade. That's the only skill I've got and it's been used for ninety years to hold a lie up and I would like, once, before I die, to put it under something real."

Sol stood up and put her arms around her sister, which they had also not done since their mother's committal, and Camila's hands came up and held on to the back of her coverall like someone in water.

"Eleven minutes," Sol said into her hair.

"Get out," said Camila. "And Sol — Pim doesn't know what he did. Don't tell him. Not ever. He'd never dispatch another shift."

Bett Osei was asleep in her chair by the runner beans, and asleep she looked like what she was, which was a very old woman with a year left, and Sol stood at the end of the terrace for a minute rather than wake her.

Then the one good ear came round.

"Optical."

"Structures wishes it had my hands."

"Structures wishes it had your — " Bett stopped, and looked at her properly, and something happened in her face. "You've been up there."

"I've been inside."

"Inside."

Sol sat on the stool and told her, quietly, in eleven minutes, with the misters going on and off over the beans: sheet nine, the linen and the glue, the fire main clamp with the shine on it where sixty years of gloves had held the door open, the grated walkway with its polished centre strip, the twelve stations, the grey box on three thumbscrews with a rating plate that said STATION 14 OF 12, and the nail at the aft end with a hardbound notebook hanging on it by a lanyard, sixty-one years of neat handwriting, fibre 9 chafe at cleat 22 — replaced, 400mm.

Bett listened with her enormous ruined hands flat on the blanket over her knees, and when Sol got to the notebook she made a sound Sol had never heard a human being make and did not want to hear again.

"Gasket samples," she whispered. "They were taking gasket samples."

"Y58. A triangle of dried adhesive stuck to the page. Hardening. Somebody's noted it in pencil so the next one would know."

"Good technicians." Bett had her hand over her mouth again, the ship's gesture. "That's what I couldn't — that's what nobody ever believes when you say it. There's no room full of men with a list. There's a girl with a notebook doing her job well, twice a year, in the dark, forty metres from the outside, and she has been told it is a calibration rig, and it is the truth, it's a calibration rig, it calibrates twelve channels to a master source and the master source is a story." She lowered the hand. "The fuel. You said you'd bring me the number."

"Nought point three one percent retained," said Sol. "And Observance has spent nought point three four since Y19. Four hundred and six kilos a year, one burn, nine seconds."

Bett Osei sat with that for a long time.

"So we drank it," she said.

"We felt it in our feet."

"We drank it. Nine seconds a year for sixty-one years, and every one of those years I stood in the Bowl with my hand on a rail because the deck was moving and I thought — " She stopped. Then, with a terrible flat wonder: "I liked it. Girl, I liked it best of everything. I'd have told you it was the only honest minute in the calendar."

"It was," said Sol. "That's why it worked."

The misters clicked off. Two terraces down, the orderly was reading the same three sentences to somebody, patient as machinery.

"There's a thing I got wrong," Sol said, "and I want to give it back to you before the eleventh, because you've carried it for seventeen years and it's the wrong weight."

"Say it."

"Idris Vance-Oyelaran. You told me he lived to be seventy-nine."

"He did."

"He died in Y79," said Sol. "Last year. Aged fifty. You had the number right and the units wrong." She watched the old woman's face. "You'd been nodding at a man of fifty for sixteen years and you'd made him old in your head, because it's easier to be angry at somebody who got a long life out of it."

Bett's mouth worked.

"Fifty," she said.

"His granddaughter's in Nav." Sol leaned forward. "Astrometry II. Twenty-six. She grew up in the berth with the window bay, and she was taught that her grandfather was a great man, and in Y79 — the year he died — she ran a bootstrap on the twelve channels and found that the effective number of independent measurements in the entire astrometric stack of this vessel is one point zero three. She filed it. Instrument Note 79/114. She wrote, in her own words, I cannot explain this."

"And they promoted her," said Bett.

"They gave her a commendation and a bench and a supervisory allowance and eleven months of not doing bootstraps, and she came to my shop at midnight on the sixth and read thirty-one pages and found an error in my grain count that made everything worse, and then she put her slate face down on my bench and left it there." Sol found her voice had gone. "She's coming forward with me on the eleventh. She'll be four metres from me holding a light. The whole thing runs in that family, Bett — the seeing and the being bought — and it took two generations and it broke the other way."

Bett Osei began to cry, silently, without appearing to notice, exactly as she had before.

"Then I'll tell you what I've got," she said, when she could. "It isn't much and you won't want it, and you're going to take it anyway. Forty-one EVAs. I know that face plate and I know that cold and I know what it does to a person's hands at the ninetieth minute. Whoever comes through that hatch on the eleventh will have been outside for forty minutes. They will be tired, and they will be at the end of a transit, and the first thing they will want is not to be in trouble." She reached out and got hold of Sol's wrist with a grip like conduit. "Don't shout at them. Don't stand in front of the hatch. You'll want to. Get out of their way, let them dog it behind them, let them take their gloves off, and then hand them the book."

"The book."

"The book, girl. Sixty-one years of their colleagues' signatures and their own line already written for the eleventh in their own hand. Don't tell them anything. Ask them to countersign your work order." Bett's grip tightened. "Because that's what you've built, isn't it. Three days of paper. You've built a thing where the only way for a decent technician to refuse you is to write down a sentence they can't write."

Sol looked at the old woman for a while.

"You'd have been very good at this," she said.

"I was very good at this." Bett let go of her wrist and sat back, and the fury came up in her face again, eighty-six years old and still perfectly serviceable. "I was very good at this in Y72 and I had twenty-eight years and I built shielding. Go on. Come back and tell me. I'd like to be told twice in one life." Sol looked at the beans for a while, because it was easier than looking at Bett.

"There's a woman who wants to see me tomorrow," she said.

"The Register."

"Registrar of Instruments. Thea Marchetti-Owusu."

"I've never met her." Bett pulled the blanket up over her knees. "I met the one before her, twice, in a corridor. Perfectly nice. Asked after my hip."

The Instrument Trust's office at Frame 22 was smaller than Sol's shop.

That was the first thing, and it was so obviously deliberate that she made herself notice it and set it aside: a room three metres by four with a plain table, two chairs, a shelf of bound standing orders in the old typeface, and one window bay looking out on the Bowl, where at 0940 the first-shift crowd was thickening on the terraces and somebody's grow-light array had just come on and turned the whole Rib a shade greener.

Registrar Thea Marchetti-Owusu was about sixty, grey at the temples, in a coverall with no grade flash on it at all, and she had made tea before Sol arrived, in two cups, and set them both down, and did not touch hers for the entire conversation.

"Sit down, Ms. Ibarra-Nakashima. I'd like to start by saying three things badly, and then you can do whatever you came to do." She sat. "One. I've read your work order. It's the best piece of engineering documentation produced aboard this ship in my lifetime, and I intend to say so in writing whatever happens today, because it's true and because the record should have it. Two. I know where you were at 0114 on the eighth."

Sol's hands were on her knees under the table and she kept them there.

"Three," said the Registrar. "I'm not going to lie to you, and I'd be grateful if you'd notice how rare that is, because it's the only currency I have left and I'm spending all of it at once."

"How do you know where I was?"

"Because Teodoro Amaral-Kwan filed a weld embrittlement sample from an original yard closeout at Frame 5 into Structures' materials queue at 0640 on the eighth, correctly bagged, correctly labelled, with a chain-of-custody tag, and it came across my desk in the ordinary way, because the forward volumes are mine." The Registrar allowed herself a very small smile. "You did it properly. That's why I know. If you'd done it improperly I'd have found out three months from now from a paint discrepancy."

"Then you know what's behind it."

"I've been in there eleven times," said Thea Marchetti-Owusu. "I sign the authority page in the front of the log book every five years. My predecessor took me in on my second day, in Y64, and I was thirty-nine years old and I sat down on that grating exactly where I imagine your astrometrist sat down, and I stayed there for about twenty minutes, and then I got up and I did the job for sixteen years." She turned her cup a quarter-turn on the table and left it. "So. That's the ground. Ask me anything you like and I'll answer it, and then I'm going to make you an offer, and I'd like you to take the offer seriously rather than heroically, because the heroic version of this conversation has been had five times and I've read all five files."

"Six," said Sol.

"Six." The Registrar inclined her head. "Ferreira-Sunquist, Vance-Oyelaran, Petrossian-Bright, Osei, Okonkwo-Reyes. And you."

"You have files on them."

"I have a file on Ansel, because a man died. I have Idris's promotion board, because I chaired the review of it in Y70 and thought it was a disgrace. I have Hana's care record, which I have read once and will not read again. I have Nadia's case, which is the worst document I have ever held in my hands." She met Sol's eyes without flinching. "I do not have a file on Bett Osei, and I'd ask you to consider what that means before you assume I'm the enemy. She's been visible for twenty-eight years. She wrote a nitrogen study in Y58 and filed it under structural hygiene, which is the most careful act of cowardice in the archive, and I've had a copy in this room since Y64, and I've never touched her, and it wasn't mercy. It was that I'd have had to explain to somebody why."

Sol said nothing. Outside, below, two children were arguing about something with enormous passion.

"Ask," said the Registrar.

"Was there ever a plan?"

"Yes. In Y19 there was a very good one." Thea Marchetti-Owusu sat back. "It's four hundred pages and it's in the safe behind you and you may read it whenever you like. The Y19 Register's position was that the Consensus was a bridge, not a destination: you hold the schedule steady for three generations while you rebuild the industrial base, you re-establish heavy fabrication, you get an injector programme going under a cover story, and somewhere around Y90 to Y110 you have a ship that can make a real velocity change and you tell everybody at the moment you can also tell them what's being done about it. Belief traded for work. Your sister's argument, a hundred years early. It's all in there."

"What happened to it?"

"Nothing happened to it. That's what I want you to understand, because it's the only thing I know that's worth passing on." The Registrar's voice did not change at all. "Nobody cancelled it. Nobody betrayed it. Each Registrar in turn inherited a plan whose first milestone was thirty years out, and each of them had a bad decade — a coolant crisis, the Y41 crop failure, the Ribs Four rebuild — and in each bad decade the plan slipped, because a plan with a thirty-year horizon is the only thing in a ship that can be made to wait, and everything else screams. And the Trim went out of the number two nozzle every year, four hundred and six kilos, because the burn was on the schedule and the schedule was the one thing nobody could touch. By the time I sat down in this chair the reserve was under half a percent and the plan was a document about a ship that no longer existed."

"You've had sixteen years."

"I have had sixteen years and I have got two things," said the Registrar. "I have got the fabrication capability at Frame 8 kept alive under Adaeze Ekwueme-Strand, who thinks she has been running a training programme for a job nobody will let her do, and who is going to find out this week that I have been protecting her budget line since Y66 for reasons she'd have hated to hear. And I have got a recomputation of the reachable set."

Sol's breath went out of her.

"You've done it."

"I did it myself, on paper, over four years, because there is nobody I could ask." Thea Marchetti-Owusu reached under the table and put a folder on it — grey, thin, unlabelled, and Sol understood with a lurch that this room had been arranged, and that the arrangement was not a trick but a courtesy, the way you set a table before you tell somebody something. "Nineteen candidates within one and a half percent of delta-v in Y11. Two in Y50. In Y80: none. The set is empty, Ms. Ibarra-Nakashima. There is nothing we can still reach that we could reach with everything in tanks one and two, and we no longer have everything in tanks one and two; we have three parts in a thousand, which will not move this ship anywhere at all. It closed sometime around Y63 and I am the only person alive who knows the date."

The room was very quiet.

"Then it's over," said Sol.

"No." The Registrar's hand was flat on the folder. "That's the sentence I've been not saying for sixteen years and it is wrong, and I want to be very precise about why, because you're going to be the one who has to carry it. The set of places we can reach by steering is empty. The set of things we can build in four hundred years is not empty. It has never been examined. We have never once, in ninety years, asked the question what kind of ship could we become, because asking it out loud requires nine thousand people to know why you're asking." She looked up. "That's the offer."

"Say it plainly."

"I'm sixty-one. I have this chair for perhaps nine more years and then I hand it to somebody, and every candidate I have is a person the apparatus has already made comfortable." Thea Marchetti-Owusu pushed the grey folder across the table. "I want you inside. Grade V, the Trust's optical seat, this room when I go. You get the safe, the Y19 plan, my reachable-set work, and cutting authority on anything forward of Frame 4 that you care to name. You suspend your channels for as long as you like; I'll countersign it this morning. And we do the thing properly, over thirty years, with an industrial programme first and a telling second, in that order, because that order is the only one that doesn't kill four hundred people in the first year, and your sister will have told you the same and she'll have shown you the Cerro numbers."

Sol looked at the folder and did not touch it.

"That's what you said to Idris," she said.

"I was fifteen years old when they said it to Idris." The first flicker of something under the surface. "Yes. It's the same offer. It's the same offer because it's the only real one, and I would like you to notice that I have made it without a single word about your safety or your sister's committee seat or the wellbeing referral that Dispatch filed on you at 1140 on the eighth, all of which I could have used and haven't."

"You just did."

"I did," the Registrar agreed, "and I'm not going to pretend that was an accident, because I said I wouldn't lie to you. Yes. That's the shape of the thing. It's kind and it's true and it's a cage, and I've been sitting in it for sixteen years keeping it clean."

Sol found that her hands had come out from under the table and were flat on the wood.

"May I say the part I came to say?"

"Please."

"Thirty years," said Sol. "You want thirty years and a proper order of operations, and everything you've told me is true, and I believe every number in that folder, and I'd probably be the same as you inside four months in that chair." She kept her voice level. "But here's what I've got that you haven't. You've got a set that's empty. I've got a hull certified for four hundred years and a nitrogen cycle that goes at six to nine hundred and a ship that has spent ninety years being maintained by people who believe the schedule. Bett Osei built forty thousand tonnes of shielding to a four-hundred-year spec because the spec was the schedule. Every gasket, every run of cable, every fatigue calculation aboard this vessel has been signed to a design life that assumed we get off at Y197 — and we don't, and every year that nobody knows that is another year of good technicians certifying the wrong thing. That's the spend. It isn't only reaction mass. It's the entire engineering basis of a ship that now has to last forever, being kept up by nine thousand people who think they're camping."

The Registrar had gone absolutely still.

"Say the last part again," she said.

"We are the wrong kind of ship because we are being maintained as the wrong kind of ship," said Sol. "You can't fix that from this room. You can't fix it with thirty years of secret industrial policy, because the work isn't in a programme, it's in nine thousand pairs of hands, and hands do what the paperwork says. The only thing that changes what the paperwork says is a fault report that can't be closed."

"And if four hundred people die of it."

"Then that's on the vote in the Bowl in Y11 and on every year since, and it's on me too, and I've done the arithmetic and it doesn't come out clean and I'm going to do it anyway." Sol stood up. "My sister writes what comes after. She's better at it than either of us and she's on the Half-Way Committee and she has nine years of the doctrine and a seven-year-old who colours the Bow Cap grey now. That's the replacement belief. It's work. It's the only load-bearing thing there is."

Thea Marchetti-Owusu looked up at her for a long moment.

"Tomorrow at 0630," she said.

"Yes."

"Kemi Odeleye-Vance will be on that hatch. She's twenty-four and she's the best technician in the detachment and she thinks she maintains a calibration rig, and she has a line already written in the log book for tomorrow because her supervisor taught her to write the next line so the date isn't forgotten." The Registrar's hands were folded on the grey folder now, unopened, being taken back. "I could stop you tonight with one call to Frame 19 and a form that Dispatch has already filled in for me out of love. I want you to know that I know that, and that I've decided, and that I'm going to go home now and sit with my wife and not make the call, and I do not know whether that is the bravest thing I have ever done or a failure of duty on a scale that will be studied for a thousand years."

"Both," said Sol. "That's usually how it comes."

"Take the folder."

"No."

"Take the folder, Ms. Ibarra-Nakashima, it's four years of work and it's the only copy and if you leave here without it I will spend tonight deciding whether to burn it." The Registrar pushed it across, hard. "Empty set. Nineteen in Y11, two in Y50, none now. Somebody has to put the date on it. Put it in your fault report as an annex and put my name on it, and don't you dare protect me."

Sol took the folder.

At the door she stopped.

"Registrar. Did anyone ever go in there and take the blanks off?"

"No," said Thea Marchetti-Owusu.

"Why not?"

The Registrar of Instruments looked out of her small window at the Bowl, where the light had gone from Highland to full day and nine thousand people were going about the morning of the tenth of the fifth month of Year 80.

"Because it's eight fasteners," she said, "and because for sixteen years I have been able to tell myself that the reason I don't is arithmetic."

At 0611 they were lying on the deck at Frame 5 with a light, taking the two dry bolts out of a fire main clamp, and nobody had come.

Teo had the clamp off in four minutes and the four tacks ground through in five, working fast and quiet in the almost-nothing gravity, and Merced stood the fire watch with her bottle and her plate hook and did not speak, and Jae knelt with the light where she was told and not where she wanted to look. Sol had the camera, the folder, the work order in a hard sleeve, and, in a stores bag on her hip, a cordless driver and eight spare captive fasteners she had drawn from the shop the previous afternoon and signed for.

At 0629 they were inside, standing on the grating in the dark with their lights off, forty metres of curved gallery running away from them into a black that had a distance to it.

At 0630 the Bell rang.

It came through eleven centimetres of laminate and the whole spar cage and the soles of their boots: one low note, ninety years old, and Sol felt her own chest loosen, absolutely against her will, the way it had loosened every year of her life. Somewhere aft of them, two kilometres of ship stood still. Somewhere at Frame 26 a boy was watching a cup of water on a table.

Then the burn.

It was a long soft shove, exactly as it had always been, and up here at the front of the ship it was not soft at all: the gallery leaned, the handrail came into Sol's hip, the grating rang like a struck pan under four pairs of boots, and then the nine seconds ended and the forward structure began to sing — a deep, complicated, dying resonance, four minutes of it, the Cap and the spars and the plates giving back the shove in every note they had.

Four hundred and six kilos. The last of it.

Sol stood in the ringing dark with her hand on the yellow rail and thought: Cami signed that on the fourth, and she'll sign nothing like it ever again, and she felt it just now in her feet in an office at Frame 20 and knew exactly where I was standing.

At 0641 the hatch at the aft end opened.

It came in with a sigh and a wash of light, and two suited figures came through it hand over hand, unhurried, the way people move who have done a thing four hundred times, and the second one dogged it behind her with a practised turn of the wrist and put her knee on the scuffed pad below it, exactly where sixty-one years of knees had gone.

Get out of their way. Let them dog it. Let them take their gloves off.

Sol stayed where she was, four stations forward, and put her light on the deck between them, pointing at the grating, so that it lit nobody's face.

The first suit stopped dead. The second walked into her.

"Good morning," said Sol. "There are four of us and we're all standing still. My name is Marisol Ibarra-Nakashima, Hull Optical and Sensing, fourteen-C. I'm here on work order 14C-0502-1 under Standing Order Four, and I'm going to stand exactly here while you get your helmets off, because you've been outside for forty minutes and I'd rather you were comfortable."

Nobody moved for eleven seconds.

Then the first suit reached up and broke the seal on her helmet and lifted it off, and she was twenty-four, with a flushed face and her hair flat with sweat, and the suit-liner mark of the neck ring across her throat, and she said, in the voice of a technician who has found strangers in her plant:

"You can't be in here."

"I know," said Sol.

"This is — " Kemi Odeleye-Vance looked down the gallery at the twelve stations and back. "This is a Trust volume. It's foam. It's not — " She stopped, and Sol watched a very good technician hear herself say a sentence about foam while standing on a grated walkway, and she gave her the four seconds it cost.

"Ms. Odeleye-Vance," said Sol. "I'd like you to countersign a work order. That's all I've come for."

She walked forward slowly and held out the hard sleeve, and after a moment the young woman took it, because she was a person who had been trained that paper is handed to you and you read it.

She read it standing up, in her suit, with her helmet under her arm and her partner behind her saying, twice, "Kemi," and being ignored.

When she got to page two she stopped, and read the paragraph about flux, and read it again.

"Who's Ekwueme," she said.

"She drew the curve for the aperture chamfers in Y2, in a shed on Phobos," said Sol. "Her great-niece is the chief of Forward Structures and she's sitting in her bay at Frame 8 right now with the door open and the lights on so that anyone who wants her knows where she is."

"This says the apertures haven't eroded."

"They haven't."

"Then the flux at the first surface is — " Kemi Odeleye-Vance's mouth kept going for a moment with nothing coming out of it.

"Ms. Odeleye-Vance," said Jae, from four metres away, in the small clear voice she had used all through the eighth reading rating plates for the record. "I'm Jaiye Vance-Oyelaran, Astrometry two, Nav. I published Instrument Note 79/114 last year. It says the effective number of independent measurements in the astrometric stack of this ship is one point zero three. I couldn't explain it and they gave me a commendation." She turned her light, at last, where she wanted to look: onto the small grey box at station fourteen, on its three thumbscrews, with the fibre feed coming into the back of it. "That's the explanation. Twelve fibres, one master source. I'd like you to tell me, as a technician, in your own words, what that device does."

"It's the calibration rig," said Kemi.

"What does it calibrate?"

"It — " The young woman looked at the box. "It projects a reference field into the channel so we can hold the alignment between refreshes. That's what it's for. That's what the table's for. We do it twice a — "

"When is the channel ever not looking at it?" said Jae.

Nobody answered, because there was no answer, because the blank was bolted over the slit, and everyone standing on that grating could see the eight captive fasteners and the Registrar's stencil and the eighteen-millimetre slot of clean chamfered laminate beyond it that had never had one grain of dust come through it in eighty-one years.

Kemi Odeleye-Vance turned around, slowly, in her suit, and looked down forty metres of gallery at twelve of them.

Her partner said, "Kem," a third time, in a completely different voice.

Sol went to the aft end and lifted the notebook off its nail by the loop of lanyard cord and brought it back and held it out with both hands, the way you hand somebody a tool.

"Your line's already in it," she said. "You wrote it in April so the date wouldn't be forgotten. Y80/05/11, 0630, trim window, supplementary refresh and station fourteen gasket. Whoever taught you to do that taught you well." She waited until the young woman took it. "There are sixty-one years of your colleagues in there, and every one of them is a good log. Fibre nine chafe at cleat twenty-two, replaced, four hundred mil. Y58, somebody stuck a gasket sample to the page because it was hardening and they wanted the next one to know. That's not a conspiracy. That's five generations of technicians keeping a machine right because they were told it was a calibration rig, and it is a calibration rig, and what it calibrates is what nine thousand people believe about where they are."

Kemi Odeleye-Vance stood in the ringing gallery holding a book in one hand and a work order in the other and said, in a very small voice:

"My gran feels the Trim. She puts the cup out."

"So does my nephew," said Sol.

She let five seconds go past.

"Standing Order 4.1," she said. "An astrometric channel's certificate rests on the documented condition of its entire optical path, from detector to first surface. There's an undocumented element in the path at station fourteen. It's Trust property and I am not going to touch it without the Trust, which is why I've been standing here for six minutes waiting for you, because you're the Trust, you're the only member of it forward of Frame 6 this morning and you have been maintaining that device since you were twenty-one." Sol got the driver out of her hip bag and held it flat on her palm, not offering it, just showing it. "I'm requesting recovery of that projector for laboratory characterisation, and removal of the blank so the path can be inspected end to end, and I'm requesting that you countersign both as the responsible maintenance grade and take a chain-of-custody tag, exactly the way Amaral-Kwan tagged his weld sample on the eighth, and exactly the way you'd tag any component you pulled out of any plant on this ship."

"If I sign that — "

"If you sign it, it's a Trust maintenance action with a custody chain, recorded in a Trust log, and nobody in ninety years will be able to call it four people and a story." Sol's voice did not rise. "If you refuse, that's your right, and I'd ask you to write the reason in that book, in your own hand, under your own line, and I'll photograph the page and put the plate in the file and I will never say one word against you as long as I live."

Kemi looked at her partner. Her partner — a man of about forty who had said three syllables in as many minutes — put his helmet down on the grating very carefully, which was the loudest thing anybody did all morning.

"Sixty-one years," he said. "Kem. I've been doing this eleven of them."

"I know."

"They told me it was a rig."

"I know, Ruy."

She put the notebook down on the grating and opened the hard sleeve and read the last page of the work order twice.

Then she said, "I'll want the tag numbers off the bag," and Sol, who had been holding herself upright by main force for four days, had to look at the ceiling of the gallery for a moment before she could get the bag off her hip.

It took nineteen minutes.

Kemi Odeleye-Vance did it herself, because it was her plant. She backed off the locking nut and slackened the three thumbscrews and lifted the projector off its mount with two hands under it, and Ruy held the bag, and she read the rating plate aloud for the record in the flat voice of a technician doing a custody transfer — projector, astrometric simulation, twelve channel, master source TA slash NAV slash SIM dash one, station fourteen of twelve, property of the Instrument Trust, Y19 — and Jae wrote it down, and Sol photographed it in the bag with the tag in frame, twice, at two exposures.

Then Kemi took the eight captive fasteners out of the blank, and they came out hand-tight, sixty-one years old, and she put them in a labelled bag too, because she was that kind of technician.

The blank came away.

Behind it was a slot two hundred and forty millimetres by eighteen, cut clean through eleven centimetres of laminate, with a nought-point-two chamfer at the far end as sharp as the day Folasade Ekwueme had specified it, and through the slot, at the end of it, small and hard and perfectly steady, was a star.

Nobody said anything for a while. The forward structure had stopped ringing.

Sol went down on one knee at station fourteen and put her eye to the slot, which was an entirely unnecessary thing to do and which she would have done if it had cost her a hand, and looked out at the Lantern with her own eye, fourteen light-years away, orange and dim and not flickering at all, because the human eye is a poor photometer.

Then she got up and went aft to where the cable run gathered, and put her palm on the cold laminate, and listened, and heard a tick, and then, a long way off, another.

"0709," said Jae, checking the slate she had brought only for the time. "The stack takes counts continuously. Channel Fourteen is looking at real sky as of about four minutes ago, and at 0800 the conditioning module is going to receive a channel whose residuals don't match the table, and at 0802 it's going to throw it out as an outlier and publish, because that's what a good stack does."

"Let it," said Sol.

"Let it?"

"Let it publish. Let it throw out the only honest channel aboard and publish the number at 0802." Sol turned around. "And then you file, at 0900, an instrument note from an astrometrist of record, stating that you were present at the removal of an undocumented emissive component from the optical path of Channel Fourteen, that the component is in Trust custody under a tag countersigned by the responsible maintenance grade, and that the stack subsequently rejected the only channel in the class receiving unobstructed sky. Attach the plates. Attach the rating plate photograph. Attach Adaeze's wall — the scatter stops in Y69, anyone who ever loved that wall can see it from across the room." She was aware that her voice had gone up and did not stop it. "That's not a hull tech's misunderstanding, Jae. That's the astrometry stack of this vessel, in its own logs, on the public board, rejecting the truth in five-millimetre type at two minutes past eight in the morning."

Jaiye Vance-Oyelaran started to laugh, and put her hand over her mouth, and Sol thought: the ship's gesture; every one of us; ninety years.

"My grandfather signed the conditioning module's description," Jae said, from behind her hand. "The two-page one. His name's on the block. He'd have been thirty-four."

"I know."

"He wrote corrects for instrumental effects in the timing chain. Eight words. I've said them out loud to apprentices."

"Then write nine better ones," said Sol.

At 0721 they went out through 5-A, and Teo closed it properly this time, four tacks and a full run to follow in the afternoon under a work order Merced had already written, and the fire main clamp went back with all four bolts torqued and witness-marked, because Ansel Ferreira-Sunquist's whole idea had been that you cannot argue with a thing you can hold, and it would be an insult to leave the ship worse than they found it.

At 0904 Instrument Note 80/041 went into the Trust's public queue with eleven photographic plates and a custody tag number.

At 0919 Chief Adaeze Ekwueme-Strand, who had sat in her bay all night with the door open and the lights on, walked out onto her own shop floor with a rolling ladder and took down the sheets for Y69 through Y80, one at a time, in front of nine members of her guild, and did not say a word, and did not have to.

At 1140, precisely on schedule, the wellbeing referral filed in good faith by D. Pimentel-Okafor, Dispatch II, auto-escalated, and a keyworker was assigned,

and his name was Yusuf Baptiste-Lindgren, and he was twenty-nine years old, and he was very good at his job.

He came to Frame 38 at 1216 with a slate under his arm and a paper cup of the good tea from the stand at 33, which he set down on the bench in front of her without comment, and Sol understood that this was training, that somewhere in a manual there was a line about bringing something ordinary into the room, and understood at the same time that he had also simply thought she might like a cup of tea.

"Ms. Ibarra-Nakashima. I'm Yusuf. I'm a keyworker out of Frame 19. I'd like to sit down for twenty minutes if that's all right, and if it isn't all right I'd like to sit down for five and come back tomorrow."

"Sit down," said Sol.

He took the bad chair. He looked at the wall of witness coupons in their labelled clips and did not ask about them.

"You know why I'm here."

"A referral."

"A wellbeing referral, filed on the eighth, escalated at 1140 today. I've read it. It's from a colleague and it's affectionate and it's three sentences long." He turned the slate face down on his knee, which she noted. "I'm required to tell you what I'm going to do with this hour and then do exactly that. I'm going to ask you some questions about sleep and food and shifts. I'm going to ask you about your sister, because there's a family link flagged on the file and it's procedurally awkward. And I'm going to ask you about one sentence in the referral, because it's in the taxonomy and I'd be negligent if I didn't."

"The stars are repeating."

"That's the one." He said it without any weight at all, which was, she thought, an extraordinary skill and probably took four years to learn. "Would you like to do it in that order or a different one?"

Sol had spent the walk back from Frame 5 rehearsing eleven ways to fight this man, and every one of them, she understood now, had been a way of losing.

"Do it in your order," she said. "And Yusuf — I'd like to ask you for something first, and it's a work request, not a favour, and you can refuse it."

"Go on."

"Record me verbatim." She put her hand flat on the bench. "Not a summary. Not subject reports. You have a slate and it takes dictation and your standard is a précis, because a précis is kinder and shorter and nobody in nineteen years has ever asked you for anything else. I'm asking you to take down what I actually say, in the words I say it in, and put it in the file as an attachment, and initial it. That's all. Whatever you conclude about me at the end, conclude it. But conclude it next to the transcript."

Yusuf Baptiste-Lindgren looked at her for a moment.

"Why?"

"Because in Y74 a woman called Nadia Okonkwo-Reyes was referred, and cared for very well by people who meant it, and there is a closed case file with her in it, and everything in that file is in somebody else's words." Sol kept her voice level. "I don't want to be summarised. That's the whole of it. I'd like the file to contain the actual sentences, so that when somebody opens it in Y120 they can decide for themselves whether I was ill."

He turned the slate over and set it up on its stand, facing the bench, and touched it twice.

"Verbatim, from now, and I'll initial each page," he said. "That's not a concession, by the way. It's in the standard. Nobody asks."

Then he did his job, and he did it beautifully, and it took an hour and eleven minutes.

He asked about sleep and she told him: eleven consecutive third shifts, four of them ending at Frame 4 or forward of it, two hours on the ninth, none on the tenth. He asked about food and she told him about the buns at 33 and the two mess sittings she had missed and the fact that she had not been hungry since the twelfth of the fourth month, which she noticed, saying it, was a date she had not previously counted from. He asked about Camila and she said: my sister is Programme, Observances Grade II, she signed the requisition for this morning's Trim on the fourth of this month, she flagged the family link herself on the eighth because it was procedurally wrong, and she and I have had four conversations in nine days and I am not going to tell you what was in them, and you should note the refusal.

"Noted," he said, and typed it, and initialled the page and turned it.

"And the sentence," he said.

"Ask it properly."

"All right." He folded his hands. "Ms. Ibarra-Nakashima. Do you believe that this ship is not where the Bridge says it is?"

"Yes."

"Can you tell me why?"

So she told him, in the right order, the way you write a fault report, and she did not hurry, and she did not raise her voice once, because she had learned in nine days that volume is a symptom and paper is not. She told him about a scruffy little binary that had played her the same nineteen minutes on forty separate nights across twenty-five years. She told him about the four percent gain detune, and what it proved, and what it did not. She told him about Spar 7 and eleven ticks a minute, and about fifty-one hours of integration and four thousand grains and a grain count that a twenty-six-year-old astrometrist had corrected downwards by fifteen percent at midnight on the sixth, which made it worse. She told him about a curve drawn in Y2 by a woman on Phobos and twelve flat zero-point histories that should not have been flat.

Then she reached past him, took a coupon out of the clip marked Y80-1 — she had signed one out of the vestibule rack on the ninth, correctly, with a chain-of-custody tag, because she had learned that too — and put it in his hand with the loupe.

"Twelve magnifications," she said. "Hold it under the lamp. Tell me what you see."

He was a careful man. He held it exactly as she showed him and took his time.

"Craters," he said. "Lots of them. Different sizes."

"Keep going. Go down in size. Tell me when they stop."

Silence for eleven seconds.

"They stop," said Yusuf Baptiste-Lindgren.

"Yes."

"They all stop at about the same — " He adjusted the coupon under the lamp, and adjusted it again, and Sol watched a man discover that his hands had begun to want a different answer. "There's nothing below that. It's just — it's polished, underneath. And there's a little raised edge round each one. All of them."

"Every one," said Sol. "That's a machine at Frame 6 with a specification and a resolution limit. Twice a year, since before either of us was born." She took the coupon back and set it on the bench between them. "Now: I want you to notice something, and then I want you to go on with your questions, because you've got a job and I'm not trying to take it off you. You have just looked into a loupe and seen a thing. You didn't take my word for it. That's the whole of what I've been asking anybody to do for nine days, and it takes four seconds, and nobody has ever done it, and the reason nobody has ever done it is not that they're stupid or wicked. It's that nobody hands them the glass."

He put his hands in his lap. His face had not changed very much, but something in the room had, and both of them could feel it.

"I don't know what I'm looking at," he said. "I want that in the transcript too. I'm not an engineer. I couldn't tell you what a coupon's supposed to look like. I've got a man's word and a woman's word and a piece of metal, and the piece of metal is exactly as persuasive as you knew it would be, and I've been trained to notice when I'm being persuaded."

"Good," said Sol. "You should notice it. I'm doing it on purpose."

That surprised a small laugh out of him, and he wrote that down too.

"May I ask you a question that isn't on the form?" she said.

"You may."

"How many P-7s are open at the moment?"

He hesitated for perhaps a second and a half, which she thought was fair.

"That's a published figure. Nine."

"Schedule-related?"

"Four."

"Four people," said Sol. "Right now, somewhere in a two-kilometre tube, four people are being cared for, kindly, by professionals, for saying a true thing. I don't know their names and neither do you, because you're not allowed to hold more than your own caseload. Have you ever closed a category seven by finding that the person was correct?"

Yusuf Baptiste-Lindgren looked at the coupon on the bench for a long time.

"No," he said. "There isn't an outcome code for it."

"Would you write that in the file?"

"I'll write it in the file," he said, "and I'll tell you what happens to it, because you've been honest with me and I'm not going to be less. It will go in as an annexed observation. The determination is not mine; it goes to a panel, and the panel will read the précis first because the précis is on the top and it is thirty seconds long and the transcript is fifty pages. And the panel will see eleven consecutive third shifts and no food and a family link and the presenting language, first bullet, and they will offer you a keyworking sequence, and it will be voluntary, and everyone will mean it." He stood up, and gathered the slate, and stopped. "And there is one thing that will make them stop, and I'd like you to hear it from me. If, before the panel sits, another grade files something that says the same thing in their own language, then the panel is not looking at one tired woman any more. It's looking at a disagreement between departments. We don't have an outcome code for that either, but it goes back in the tray."

"Nav filed at 0904," said Sol. "Structures files this afternoon."

He nodded slowly, as if a small technical matter had been resolved.

"Then eat something," he said. "That's the whole of my clinical advice and it's the only part of this hour I'd stake anything on. You look like a coupon."

"You're the second person to say that this week."

"Then it's probably in the file already," said Yusuf, and put the good tea, untouched and gone cold, back into her hands on his way out.

At 0802 on the eleventh of the fifth month of Year 80, the astrometry stack of the Anabasis received counts from twelve photometric channels, found that one of them was reporting a sky which did not match the conditioning table, rejected it as an outlier with a two-line entry in a log that nobody had read since Y31, and published the daily solution.

The board in the Bowl came up at 0805 as it had every morning for ninety years.

DAYS TO HALF-WAY, 6,195.

Beneath the number, in five-millimetre type, the word PROVISIONAL, and a work order reference.

Nobody noticed. That was the part Sol had prepared for and had still, somehow, not been ready for: she stood at the rail of the Bowl at 0810 with the smell of cut grass in the air handlers and watched two hundred people cross the terraces below her, and a woman went past with a tray of bread rolls, and somebody's grow-light array came on and turned the whole Rib a shade greener, and the Mood Index stood at 7.1, and the ship went on with its morning above a number that had a footnote on it for the first time in its history.

She had thought there would be a moment. There was no moment. There was only a Tuesday.

By 0900 there were three moments, and none of them were in the Bowl.

At 0904, Instrument Note 80/041 entered the Trust's public queue: four pages, eleven photographic plates, a custody tag number, and nine words in the last paragraph that Jaiye Vance-Oyelaran had written standing up at her bench without sitting down first — the stack rejected the only channel receiving unobstructed sky.

At 0919, Chief Adaeze Ekwueme-Strand took eleven sheets of hand-plotted erosion data off her own wall in front of nine members of her guild, and clipped them to a board, and wrote across the top of the board in grease pencil, in letters a hundred millimetres high: SCATTER STOPS Y69. ASK ME WHY.

And at 1104, a schoolteacher at Frame 24 named Ify Aduba, who taught the eight-year-olds their frames and showed them the animation of the Sand every spring, submitted a curriculum query to the Instrument Trust asking whether the ablation figures in the teaching pack were still current, because a child in her class had told her, with enormous seriousness, that the Bow Cap was grey and cold and did not glow, and that his aunt had put a pickup on a spar, and that it was the only sound aboard that came from outside.

Sol did not learn about the third one for four days, and when she did she had to go and stand in a service corridor for a while.

Registrar Thea Marchetti-Owusu issued it at 1500 on the eleventh, from a room three metres by four, and it was one page.

DETERMINATION OF THE REGISTRAR OF INSTRUMENTS — 80/D/1.

1. Work order 14C-0502-1 is upheld in full. The suspension of certificates on Photometric Channels 1–12 stands until characterisation is complete. No astrometric solution shall be published on the authority of a suspended channel; publication as PROVISIONAL, on gyroscopic and historical authority, is to continue and is to be marked as such in type of the same height as the figure it qualifies.

2. Characterisation shall be executed by Forward Structures under Chief A. Ekwueme-Strand, with Hull Optical & Sensing in attendance, with cutting authority forward of Frame 4 as required, and with full access to the Instrument Gallery (Sheet 9, Fabrication Set, Ekwueme & Daughters) which is hereby re-entered on the maintenance set as an occupied volume with handrails, lighting and twelve stations, its designation as foam-filled void (Rev. 2, Y13, TA/REG) being an error of this office which I am today correcting eighty-one years late.

3. Twelve projectors, astrometric simulation, master source TA/NAV/SIM-1, remain the property of the Trust and are to be recovered to laboratory custody, tagged, and preserved intact. They are not to be destroyed. They are evidence and they are also, I am advised, rather good instruments.

4. Annexed: RECOMPUTATION OF THE REACHABLE SET, Y11–Y80, in my own hand, four years' work, unreviewed. Nineteen candidates in Y11. Two in Y50. None in Y80. The set closed at some point between Y61 and Y65 and I am the only person alive who has computed the date. Whoever reviews this should begin by trying to prove me wrong; I have not been able to.

5. I have this morning declined to make a telephone call which would have stopped all of the above, and I record that I considered it, and that I considered it for some time.

T. MARCHETTI-OWUSU, REGISTRAR OF INSTRUMENTS.

Sol read it on the public board at 1520, sitting in the alcove at Frame 33 with the tamarind vendor five metres away and a bun she had actually eaten, and when she got to paragraph five she found she had put her hand flat on the terminal casing, the way you do on a machine that is running rough.

The Registrar's office door was open when she got to Frame 22. Thea Marchetti-Owusu was standing at her small window with her back to the room, watching the Bowl.

"Don't thank me," she said. "You'll want to and it will make me sick."

"I wasn't going to thank you. I was going to ask what it costs."

"Nothing, today. That's what's obscene about it." The Registrar turned around. She looked exactly the same and about four years older. "Nobody is going to come for me. I hold the chair; the chair holds the forward volumes; the determination is within my authority to the letter and every line of it is defensible in a room. Do you see? That's the shape of the thing, and you should learn it now, because you'll be in this chair inside a decade whether you like it or not. There was never a lock on the door. There was a habit, and it was ninety years old, and habits die when one person with the right desk breaks them on a Tuesday afternoon."

"Then why — "

"Why didn't I? Because for sixteen years I told myself the arithmetic said wait, and the arithmetic did say wait, and the arithmetic was correct." She sat down heavily in her own chair. "And then a hull tech told me that the spend was not only reaction mass, and I could not answer it, and I have not been able to answer it since Wednesday morning, and I am sixty-one years old and I have signed four hundred certifications to a four-hundred-year design life on a ship that is now required to last forever." She looked up. "That was the sentence, Ms. Ibarra-Nakashima. You should know which one it was. Hands do what the paperwork says."

"They'll go to Programme," said Sol.

"They have already gone to Programme. Programme went to Programme; it's not a conspiracy, it's a Tuesday, somebody with a determination in front of them thinks this will need careful communication and picks up a slate, because that is what a competent person does." The Registrar folded her hands. "There'll be a Continuity assessment by tomorrow. There'll be a proposal to hold the determination in abeyance for ninety days pending a communications plan, and the proposal will be made by decent people and it will be reasonable, and ninety days will become a year, and a year is how it has always been done."

"My sister is drafting the communication."

"I know," said Thea Marchetti-Owusu. "I'm on the Half-Way Committee with her. She asked me, in a corridor, in the pleasantest voice you have ever heard, whether I intended to publish before or after she'd written it."

"And?"

"I told her the truth, which is that I intend to publish exactly what I published, at the time I published it, and that if her office wishes to be useful it has about eighteen hours." The Registrar's mouth did something that on a less exhausted face would have been a smile. "She said: that's all I wanted. And then she said something I've thought about all afternoon. She said, don't let it come in as the enemy of the Bell."

Camila did not sleep on the night of the eleventh, and Sol knew this because she was in the room.

The Programme's Observances office at Frame 20 was long and low and lined with cabinets of physical paper going back to Departure, and at the far end there was the mural: the Bloom, blue-white, with the silhouetted figures doing something heroic that nobody had ever been able to specify. Camila worked with her back to it. She had a stack of ration card stock, because she liked paper, and a pot of tea gone cold twice, and she wrote in longhand and crossed out and wrote again, and at 0210 she said, without looking up:

"It's too long."

"How long is it?"

"Four hundred words. It has to be under two hundred or people will read the first line and the last and invent the middle, and the middle is where they'll put the worst thing they can think of." She crossed out eleven lines with a single stroke. "Read me your first paragraph again. The work order. The chamfer one."

Sol read it.

"Two explanations exist," Camila repeated. "God, that's good. That's the whole thing. Two explanations exist. You didn't tell anybody what to think, you told them there were two doors and one of them was locked." She wrote something. "That's the shape. Not we are not moving. Never that. There is a disagreement between our instruments and our records, and we are going to settle it."

"That's a lie by omission."

"It is not." Camila put the pen down hard. "It's the true sentence with the smallest number of implications attached, and the implications will arrive on their own, over eleven weeks, in argument, in the mess, at the bench, from people who worked it out themselves — and a thing you work out yourself does not knock you over, Sol, it lands. That's not doctrine. That's every parent who ever lived."

She picked the pen up again.

"And it has one more part, and this is the part I have been trying to write since I was nine days old in this, and I can't get it, and you're going to have to help me because it's yours."

"What part?"

"The work order," said Camila. "It's no good telling nine thousand people there's a fault if the next line isn't a job. That's the whole method and I gave it to you in my kitchen and now I have to ship it. So." She turned the page around. "What can a person do about this tomorrow? Not Structures. Not Nav. A woman who runs a laundry at Frame 31. A man on the beans. What's the work?"

Sol sat down on the edge of a cabinet full of ninety years of processions.

She thought about it for a long time — longer than she had thought about anything since the twelfth of the fourth month — and the answer, when it came, was so plain that she laughed out loud in an empty office at two in the morning.

"Design life," she said.

"Say more."

"Every certification on this ship is written to Y197 plus a margin. Every gasket, every cable run, every fatigue calculation, every stores rotation, every seed line in the Grove." She was on her feet now. "There are perhaps four hundred thousand certified items aboard and the number in the box is wrong on all of them, and the people who know which ones matter are not on any committee, they're the ones with the hands. Cami — you can't ask nine thousand people to feel something about four thousand six hundred years. But you can ask a woman who runs a laundry which of her machines were built to last a hundred and seventeen, and she'll know, she'll know off the top of her head, and she'll be furious in the correct direction inside a week."

Camila was writing very fast.

"A recertification," she said. "Ship-wide."

"Call it the Survey."

"That's a Milestone word." Camila's pen stopped. "That's a Milestone word, Sol, do you understand what you've just handed me? I have a committee of nineteen people who have spent nine years planning a procession for a half-way point that isn't there, and they are going to find out this week that their life's work is a fiction, and I have been sick about it for four days, and you have just given me somewhere to put them." She wrote three lines and read them and did not cross them out. "Every grade. Every item. Everybody's own bench first. Six thousand one hundred and ninety-five days is a very long procession."

"And the Bell stays," said Sol.

"The Bell stays," said Camila. "The Bell rings on the eleventh forever, one note, at 0630, and nothing goes out of the number two nozzle ever again, and in eleven years nobody will remember which of those two things was the ceremony." She sat back and pressed the heels of her hands into her eyes, and held them there, and when she took them down she was crying and perfectly steady. "Two hundred words. I've got a hundred and forty. Do you want to hear it?"

"Yes."

Camila read it aloud, standing, with her back to the Bloom.

It began: There is a disagreement between our instruments and our records. It said that a hull technician had filed a fault report, and gave its number. It said that the Registrar of Instruments had upheld it, and gave the determination's number, and said it could be read in full by anybody, today, on any public terminal. It said that the daily position would be published as provisional until twelve apertures had been inspected from the outside for the first time in eighty years, and that this would take months, and that the number on the board would probably change. It said that the schedule of this ship rested on measurements which had not been independently verified within living memory, and that this was nobody's fault living and everybody's business now. It said that a ship-wide recertification of design life would begin on the twelfth, at every bench, in every grade, starting with your own tools. It said what would not change: water, air, school, berth, the Grove, and the Bell.

It ended: We would rather tell you nine tenths of a thing today than a whole thing in a year. The remaining tenth will be argued about in public. Bring your hands.

Sol found she could not say anything at all.

"Too long by six words," said Camila, "and the last line is yours, I stole it out of your mouth in my kitchen, and I'm not giving it back."

She went at 1400 on the twelfth, with the grey box in its bag on her hip and a custody tag on the bag.

The Long Rib had heard. She knew that from the corridor: two orderlies talking fast and low by the lift, and the reading-aloud voice at the far end going on exactly as before, patient as machinery, three sentences at a time. The board at the terrace entrance said MOOD INDEX 5.8, the first figure below six point two in eleven years, and Sol looked at it for a moment and thought: there it is. That's the four hundred people. That number is the beginning of the bill.

Bett Osei was awake, in her chair, with the blanket over her knees and the runner beans dripping behind her, and she had a printout of the determination in her lap — an actual printout, on flimsy, which somebody had gone and made for her.

"Optical," she said.

"Structures wishes it had my hands."

"Structures," said Bett, "has just re-entered a forty-metre walkway on the maintenance set with handrails and lighting bosses, so Structures is having a day." Her one good ear came round. "Paragraph five. Have you read paragraph five?"

"I've read paragraph five." "Say what it is." Bett's enormous hands were flat on the flimsy. "I want to hear you say what it is, because I have read it nine times and I keep making it into something I want."

"It's a woman putting on the record that she nearly didn't," said Sol. "Nothing else. She had a form and a name at Frame 19 and it would have worked, and she went home and sat with her wife and didn't make the call, and then she wrote it down so that nobody in a hundred years can say the choice wasn't there."

"That's what I thought it was." Bett folded the flimsy in half, and then in half again, into eighths, the way Sol folded things, which Sol had never noticed she had learned from her. "Twenty-eight years I've been telling you people there's no room full of men with a list. Nobody ever believes it. And here's a woman who was the room, and she was one person with a desk and a bad conscience, and she broke it on a Tuesday afternoon because a hull tech said a sentence she couldn't answer." She put the folded paper under the blanket. "What was the sentence?"

"Hands do what the paperwork says."

Bett shut her eyes.

"Say it again."

"Hands do what the paperwork says." Sol pulled the stool over and sat. "Bett, that was yours. I didn't work it out. You said it to me eleven days ago in this chair. You said I built it to a four-hundred-year certification because that was the spec and the spec was the schedule and I knew the schedule was a lie and I built it anyway. I've just been carrying it about repeating it to people with desks."

"That's the whole trade," said Bett, without opening her eyes. "The carrying. Nobody tells you that at twenty-two."

Sol took the bag off her hip and set it on the blanket over the old woman's knees.

"What's this."

"Open it. It's tagged, so don't take it out of the bag, and I have to have it back at Frame 8 by 1600, and there are eleven people in this ship who will be extremely unpleasant to me if it comes back with a fingerprint on the window."

Bett looked at her for a moment. Then she pulled the bag open with two fingers and looked into it, at the grey box the size of a bread loaf, on its three thumbscrews, with the fibre stub still in the back of it and the filter wheel on the side and the little glass window in the front the size of a thumbnail.

She read the rating plate. Her lips moved.

PROJECTOR, ASTROMETRIC SIMULATION, 12-CH. MASTER SOURCE TA/NAV/SIM-1. STATION 14 OF 12. ALIGN TO 0.4 ARCSEC. PROPERTY OF THE INSTRUMENT TRUST. Y19.

"Station fourteen of twelve," she said.

"Somebody stencilled it wrong sixty-one years ago and nobody ever cared, because nobody who went in there needed telling which station was which."

"Sixty-one years." Bett did not touch it. She sat with the open bag on her knees and looked into it the way people look into a grave. "It's small."

"It's smaller than my drum."

"It's small." Her voice cracked on the second one. "Girl, I have had a thing in the middle of my chest since Y72 the size of a lift motor. I have carried it up ladders. And it's — " she made a helpless gesture with one ruined hand, two hand-spans apart — "it's a box. It's a box a decent technician could service in twenty minutes with a two-mil driver and a can of air."

"They did," said Sol. "Twice a year. There's a notebook. In Y58 somebody stuck a gasket sample to the page in pencil because it was hardening and they wanted the next one to know."

Bett Osei began to laugh, and it went into the cough, and the cough went on a long time, and Sol stood and held her shoulder and felt the bones in it like conduit under lagging, and one of the orderlies came to the end of the terrace and looked, and Sol shook her head, and the orderly went away.

When it was over Bett wiped her face with the flat of her wrist.

"You said you'd bring me a number," she said. "You brought me two. Bring me the third. The one you didn't put in the letter."

"The reachable set is empty," said Sol. "Marchetti-Owusu computed it by hand over four years, and she's the only person alive who's done it, and it's annexed to the determination in her own writing. Nineteen candidates in Y11. Two in Y50. None now. It closed sometime between Y61 and Y65."

"So there's nowhere to go."

"There's nowhere to steer."

"Say the difference, and say it slowly, because I'm eighty-six and I would like to get it right the first time."

Sol crouched down so that she was under the old woman's good ear.

"The set of places we can reach by steering is empty," she said. "The set of things we can become in four hundred years has never once been examined, because examining it out loud requires nine thousand people to know why you're asking. That's all. That's the entire content of what we did yesterday. We didn't find a way out. We found permission to ask the question in daylight, and eighty years of not asking it has cost us everything that could have been spent, and it will keep costing at exactly the same rate until every certification on this ship gets its number changed."

"Four hundred thousand items," said Bett.

"Four hundred and eleven thousand, by the Quartermaster's count, at 0900 this morning. Cami's office has a name for it. They're calling it the Survey."

"That's a Milestone word."

"That's what she said."

Bett was quiet for a while. The misters came on over the beans with their small sigh, and the leaves went on dripping into the sudden quiet, and two terraces down the reading-aloud voice began its three sentences again from the top.

"Forty thousand tonnes," she said.

"Yes."

"Forty thousand tonnes of internal shielding at Ribs Two through Six, laid in by me and by a crew of eleven between Y49 and Y66, certified to four hundred years." Her hands had begun to move on the blanket, and Sol watched them do it and understood, with a lurch under the ribs, that they were not shaking. They were working. They were going through something. "Sol. Do you know what the four-hundred-year number actually is? Do you know how it was arrived at?"

"No."

"It's the laminate. It's the interlayer creep in the bonded laminate, and it's a bad number, it's a lazy number, it came out of a Phobos test coupon programme that ran for eleven months and got extrapolated by four hundred, and I knew it was lazy in Y51 and I said so and I was told the spec is the spec." Bett's chin came up. "But the steel's good. The steel behind it is good for two thousand years if you keep the water off it, and the reason we bonded laminate to it in the first place was mass, because mass was velocity, because we were going somewhere and every tonne was a day." Her eyes were terrible and bright. "Girl. We're not going anywhere. Mass is free. Mass has been free since Y7 and nobody has been allowed to notice, and there are four hundred thousand items on this ship that were designed light for a reason that stopped existing eleven years before I was born."

Sol sat down on the stool because her legs had gone.

"Say that again," she said.

"Mass is free," said Bett Osei. "Write it down."

"I don't need to write it down."

"Write it down, Optical, you'll be dead in forty years and this is the only useful thought I've had since Y58." She was gripping the arm of the chair. "That's the answer to your Survey. Every item on that list was specified by somebody optimising for a hundred-and-seventeen-year cruise at a tenth of light. Every single one. Thin, light, sacrificial, cheap to accelerate. And you're going to go round four hundred and eleven thousand of them changing the number in the box and half of them will fail their new number, and everybody will be very frightened, and the answer to nearly all of it is make it heavier. Thicker plate. Solid instead of bonded. Steel instead of laminate. We've got a ship full of metal we were dragging to Hale and we are not dragging it to Hale, and it can be cut up and used."

"There's no drive."

"There's no drive, so who cares what it weighs." Bett laughed, one bark. "That's the thing you people can't feel yet because you've all grown up counting kilos. I've been counting kilos since I was nineteen. Every plate I ever hung I hung light, and it hurt me every time, and I did it because a woman with a slide rule in Y-3 was buying a day of arrival with it." She sat back, breathing hard. "That constraint is gone. It went in the Bloom and nobody's spent a day of the last seventy-three years enjoying it."

Sol had her hands over her mouth. The ship's gesture. She took them down.

"I need you," she said.

"You need a corpse."

"I need eleven months of a corpse who knows why every load-bearing decision on this ship was made light." Sol leaned in. "The Survey starts tomorrow at every bench in every grade and by the end of the month there will be nine hundred people filing recertifications and not one of them will know what you just told me. Bett — the nitrogen study. Y58. It's filed under structural hygiene."

"I know where I filed it."

"I've asked the Registrar to have it pulled and re-entered as a Class One environmental finding with your name on the top of it, and she's agreed, and it goes on the public board on the fourteenth." Sol watched the old woman's face. "It'll have your name on it, in the Bowl, on a board, next to a number that says the air stops working somewhere between six and nine hundred years. People are going to be extremely angry with you for about a fortnight."

Bett Osei stared at her.

"Angry with me," she said.

"Furiously. You buried it under cleaning for twenty-two years."

And the old woman put her face down into her enormous ruined hands and wept, properly, with sound, for the first time in front of anybody in twenty-eight years, and what she said, when she could say anything, came out muffled and cracked and absolutely clear:

"Good."

Pim was in dispatch at 2214 that night with his boots on the console and something in his cheek, and he took them down when she came in, which he had never done.

"Sol."

"Pim."

"They've got the board saying PROVISIONAL in forty-mil type." He was not chewing. "Same size as the number. You can read it from the far rail."

"That's in the determination. Paragraph one."

"I know it's in the determination, I've read the determination, everybody's read the determination, the tea stand at 33 has run out of tea." He looked at her, and Sol watched a kind man come very close to a question and then, with a visible effort of love, go around it. "You want the stack held?"

"No. Hold Fourteen out of solution, though."

"Fourteen's already out. It's been out since 0802, the stack's throwing it as an outlier every cycle and logging it." He turned back to his screens. "It's making a hell of a mess of the log."

"Let it make a mess."

"Oh, I'm letting it." He put something new in his cheek. "Ninety years that log's had eleven lines a week in it. It's had four thousand today. Every one of them says the same thing." He read it aloud, flatly, the way you read a part number. "Channel 14 rejected: residual exceeds conditioning tolerance. Four thousand times, Sol."

"Yes."

"That's a machine shouting," said Pim.

Sol stood in the doorway of dispatch for a moment and thought about three sentences filed in good faith on the eighth, every one of them love, and about a promise she had made in a kitchen at Frame 26.

"Don't work a double," she said. "You look like a coupon."

"That's rich," said Pim, "coming from you," and she went out into the Quiet with the lumens at eleven percent and the amber runners along the deck seams like the last coals of something, and did not tell him, then or ever.

She went forward on the fifteenth, at 0140, with a scribe in her pocket.

The vestibule at Frame 4 was not what it had been. There were two portable lamps rigged on stands and a cable snaking aft, and a stack of new coupon blanks in a crate, and a hand-lettered sign taped to the rack that said ROSETTE 3 — FIRST REAL PULL SINCE Y69 — SCHEDULED 5/19 0400 — A.E-S., and under it, in a different hand, somebody had written bring the glass.

The coupon rack still held its sixty numbered slots. Every one of them had a red tag on it now, and the tags said EVIDENCE — DO NOT DISTURB — TRUST CUSTODY 80/D/1, and Sol stood in front of thirty years of manufactured proof and felt nothing much at all, which she supposed was the correct amount.

Then she knelt at the base of it, and cleared the dust off with her thumb, and found that somebody had got there first.

The coin was as it had been: the old ship's chit, heated and pressed into the deck coating, COUNT THE PITS, A. F-S., four marks and a fifth across them. And beside it, on the bare plate where she had cut her letters eleven days ago — COUNTED THEM. NOW COUNT THE FUEL. IT IS SPENT. BRING METAL. NOT WORDS. — there was new scribework, small and careful, in a hand that was not hers.

K. ODELEYE-VANCE, TA/MD. I MAINTAINED IT. I DIDN'T KNOW. I KNOW NOW. STN 14 BLANK OFF 11/5/80 0703 — SHE LET ME DO IT MYSELF.

And under that, in the round young writing Sol had last seen in a notebook hanging off a nail:

I HAVE COUNTED SIXTY-ONE YEARS OF SIGNATURES. THEY WERE ALL GOOD LOGS. THAT IS THE WORST PART. BRING THE GLASS.

Sol crouched there for a long time with her head torch throwing her own shadow across it.

Then she took out her scribe, and she did not make a tally mark, because five people in thirty years had made tally marks and a tally is a thing you make when there is nowhere to file. She cut, instead, in letters as small and as square as she could hold them, on the plate between Ansel's coin and Kemi's confession:

WO-14C-0502-1
TA DETERMINATION 80/D/1
INSTRUMENT NOTE 80/041
READ THEM ON ANY PUBLIC TERMINAL

And underneath, because there would be a seventh and an eighth and a nine-hundredth, and because they would need to know that the door was open now and that walking through it was not an act of heroism but a shift:

THE SURVEY STARTS 12/5/80. GO TO YOUR OWN BENCH FIRST.

She looked at it, breathing white.

Then she put the scribe away and stood up, and her knees complained, and she thought: forty-one years old, and I have never in my life felt the floor under me be so exactly a floor.

Station fourteen, at 0230.

They had lighting in the gallery now — proper strings, clipped to the lighting bosses that a woman on Phobos had specified and that had waited eighty-one years for a bulb — and the whole forty metres of it stood revealed, curved and yellow-railed and utterly ordinary, a walkway in a ship, the least mysterious place imaginable. Merced had already stencilled a number on the deck at each bay in fresh white paint, correcting the numbering to Optical's, because she had said, with great firmness, that if the gallery was going on the maintenance set then it was going on properly.

Station fourteen was bare. The mount stood empty on its three thumbscrews with a red tag on it. The blank lay in a labelled bag on the grating with its eight fasteners.

The slot was open: two hundred and forty millimetres by eighteen, cut clean through eleven centimetres of laminate, with a nought-point-two chamfer at the far end as sharp as the day it was cut.

Sol clipped the portable detector head to the bracket — the spare, her own, drawn from stores on Thursday and signed for — and ran the cold chain and watched the temperature curve fall away like a dropped rope, seventy kelvin, sixty, the noise floor dropping with it into that clean black ridiculous quiet where a machine can hear individual particles of light arriving from fourteen light-years away.

Then she put the buds in and sat down on the grating with her back against the yellow rail, and switched the counts to audio, and listened to the Lantern.

It was there. Of course it was there; it had been there the whole time, throwing its fits into a vacuum with nobody watching, four point three one days a turn, a swollen orange primary and a pinched red dwarf young and furious and absolutely indifferent. The eclipse ingress came at a phase she had never seen, because she had never in nineteen years seen a phase that had not been drawn out of a bag.

And on top of the calm periodic dimming, the flares came.

Dum. Rest. Rest. Da-dum-dum.

Her hand went on her thigh, out of nineteen years of habit, out of a whole life of turning data into rhythm — and got it wrong. It anticipated a doublet that did not come and missed a spike that did, and she felt her palm stumble against the deck of her own leg like a foot finding a stair that wasn't there.

Sol laughed out loud, alone, in a lit walkway at the front of a ship going nowhere at seven hundred and fifty kilometres a second.

She tried again. Got it wrong again. There was a long dead patch, four minutes of nothing, and then three in eleven seconds, and she caught none of them, and she would never catch any of them, because it was a flare star, and that was the entire content of the phrase, and no living hand would ever anticipate it again.

Pilar's Stairs was a recording. Somewhere in the Trust's evidence lockers, in a grey box the size of a bread loaf, there was a night in some year before her birth when a red dwarf fourteen light-years away had stumbled up a flight of stairs, and five generations of technicians had kept it beautifully, and it had been played to her twice, four years apart, in the dark, and she had loved it.

This was not that. This was worse and it was clumsy and she could not hold it in her hands.

She sat with her palm flat on the grating and let it be unpredictable at her for twenty minutes, and at some point she stopped trying to drum it at all and simply listened, which she had not done since she was twenty-two years old with a probe against a spar and a woman's hand on her shoulder telling her that was the galaxy hitting the front of her house.

At 0301 she pulled the buds out and took the head off the bracket and packed it, because she was on shift and there was a channel at Frame 40 that would want its certificate back one day and eleven others behind it, and because the Survey had opened four hundred and eleven thousand items that morning and eleven of them were hers.

On her way aft she stopped at the nail.

The notebook hung there on its loop of lanyard cord, sixty-one years of neat handwriting, restored to its hook by a twenty-four-year-old who had refused, absolutely and in writing, to let it be taken to an archive. Sol turned to the last written page. Kemi's line for the eleventh was there in April's ink. Beneath it, in Kemi's own hand, dated the eleventh, was one more:

Y80/05/11 — 0703 — blank removed stn 14, projector recovered to Trust custody under tag 80-0114, work order 14C-0502-1, in attendance Ibarra-Nakashima (Optical), Vance-Oyelaran (Nav), Amaral-Kwan and Ekwueme-Strand (Structures), Odeleye-Vance and Ferrão (TA/MD). Channel 14 receiving unobstructed sky as of approx. 0705. This log continues. K. O-V.

This log continues. Sol read it twice, and put her thumb on it, and hung the book back on its droop of welding rod, and left it there, because that was where it lived and it was still, in the strict sense, a maintenance record.

Tico's new model arrived at her berth on the seventeenth, delivered by his mother, who put it on the fold-table without comment and stood back with her arms folded like a woman presenting a report.

It was forty centimetres of ration card stock, the spindle segments individually rolled, the spin ring on a paper axle so it turned, the frame numbers in a seven-year-old's hand every four segments.

The Bow Cap was grey. He had rubbed it with pencil lead and then gone over it with something abrasive, so that it was dull and rough and did not shine at all, and along its face he had drawn twelve tiny slots, and behind them, in pencil, in a line curving round inside the hull where nobody would ever see it, he had drawn a walkway with a rail.

There was a label on the front, in careful block capitals: NOT TO SCALE. IT IS COLD. IT IS JUST STANDING THERE TAKING IT.

"He wants to know if the gallery's the right length," said Camila.

Sol picked it up and turned it over and looked at the little pencil line running round inside the paper hull, forty metres of it, and could not speak for a moment.

"It's four segments too short," she said, when she could. "Tell him to measure it off sheet nine. Tell him Chief Ekwueme-Strand will let him see the drawings if he writes and asks properly, in ink, with a date on it."

"He's seven."

"Then he'll be eight when the answer comes," said Sol, "and it'll be a good answer, and he'll have it in his hand."

Camila made a small sound and sat down on the edge of the bunk, and looked at the drum on its hook, and at the paper ship, and at her sister.

"Mood Index came out at 5.1 this morning," she said. "Lowest since Y44. There's a working group. I'm chairing it."

"Are you all right?"

"No," said Camila. "Nobody's all right. Four hundred and eleven thousand certifications, and a woman at Frame 31 filed the first one at 0611 on the twelfth — a laundry press, Sol, a laundry press — and she wrote in the box, in the reason field, because I was told to look at my own bench first, and then she wrote out four hundred words about interlayer creep that made three engineers cry." Her mouth went crooked. "There were eleven of those on the twelfth. There were nine hundred yesterday. It's not going to stop. It's the worst thing I have ever been part of and I would not swap it for the Half-Way procession if you held me over a lock."

She stood up and straightened her coverall.

"The Bell rang this morning," she said. "0630, one note. Nothing burned."

"I know," said Sol. "I felt it."

"You felt the Bell."

"I felt the Bell," said Sol, "and then I felt the ship not move, and it was the most honest minute in the calendar."

The first one came on the eighteenth.

Camila brought it to Frame 38 herself, at 0740, still in yesterday's coverall, and she did not sit down and did not put anything on the bench. She stood in the doorway of the hull shop with a single sheet of flimsy held down at her side and said:

"Rufino Adeyemi-Løkke. Sixty-one. Propellant gauge technician, tanks one and two."

Sol put down the cryo fitting she had been cleaning.

"When?"

"Sometime in the second shift. They found him at 0410 in the tank two inspection gallery, at his own station, with his gauge log squared up on the bench beside him." Camila's voice was doing the thing it did in a committee room, which Sol had never before heard her use in front of family. "He'd opened a nitrogen purge line and sat down."

"Adeyemi-Løkke."

"Yes." Camila's chin came up half a centimetre. "I checked before I came. Great-grandson. R. Adeyemi-Løkke, TA maintenance detachment, first eleven pages of your notebook. It's a common enough name. It's also not."

Sol got up and went to the wall of witness coupons and stood with her back to the room, which was not a thing she had ever done in front of her sister.

"Thirty-eight years," said Camila. "He read those gauges every month for thirty-eight years, Sol. Two hundred and eleven kilos down, two hundred and nine kilos down, and he signed each one, and every year in the fifth month there was a step in the curve four hundred and six kilos deep and he wrote observance in the reason field because that's what the form said to write." She came into the room at last and put the flimsy on the bench. "He left a note. Three lines. His daughter has consented to publication and I'd rather you read it here than on the board at eleven."

Sol turned around and read it.

I gauged the tanks. I never once asked what it was for.

Nobody lied to me. That is what I cannot get past.

Please don't stop the Survey.

Underneath, in Camila's own hand, in pencil, was a fourth line that was not part of the note but was, Sol understood, part of the document:

CAUSE: SELF-ADMINISTERED. HE LEFT A NOTE. THE NOTE IS PUBLISHED IN FULL AT HIS FAMILY'S REQUEST.

"They wanted hypoxic event," said Camila. "Not out of malice. Out of ninety years of habit and a genuine, sincere, well-founded belief that the plain words would cost more lives than they saved. Frame 19 wanted it. Two of my own committee wanted it. The care taxonomy has a paragraph on contagion and the paragraph is correct, Sol, that's the thing I need you to hold — it is a correct paragraph, it is supported by the Cerro data, and if we are honest we will kill some number of people that we would not have killed by being careful."

"And you overruled it."

"I didn't overrule anything. I don't have that grade." Camila's mouth twisted. "I went and stood in a room at 0530 and said that the phrase hypoxic event had been used to describe Ansel Ferreira-Sunquist in Y69 and Hana Petrossian-Bright in Y71 and that both were in the Trust file annexed to a public determination, and that if we used it this morning it would be on a public terminal by lunchtime with those two other names beside it, and that we would then have to explain the difference, and that we would not be able to." She wiped her face with the flat of her wrist. "So I won on tactics. I want you to know that. I did the right thing for a reason I'd be ashamed to say out loud, and I've been sick since, and I'd do it again, and that is apparently my whole profession."

Sol read the three lines again.

Please don't stop the Survey.

"Cami."

"Don't."

"Cami, four hundred and eleven thousand items — "

"Four hundred and nine thousand, eight hundred," said Camila. "Eleven hundred closed already. Do you know what people are doing? They're not filing recertifications, most of them. They're going and standing in front of the thing they've maintained for twenty years and looking at it, and then they're going to find somebody older and asking why it was built that way." She sat down on the bad chair at last, heavily, like something set down. "The Quartermaster's clerk at 31 filed a hundred and forty items in one day and every one of them says the same thing in the reason field. Specified light. That's all. Two words. Over and over. Specified light, specified light, specified light."

"That's Bett."

"That's Bett Osei's line going round nine thousand people in six days, and by Thursday it will be a joke, and by next month it'll be a thing people say to each other when they want a shelf put up." Camila laughed, one wet syllable. "Mood Index came out at 4.4 this morning. Forty-one open P-7s. Frame 19 has cancelled all leave and my office has been instructed to produce a Continuity assessment by the twentieth and there is a proposal in the tray, drafted by a woman I have known since I was nine, to hold the determination in abeyance for ninety days pending a communications plan."

"Will it carry?"

"It would have carried on the twelfth." Camila stood again. She could not seem to stay in one attitude for more than a minute. "It won't carry now, and the reason is the stupidest thing you have ever heard and I want you to appreciate it properly, because you built it and you did not know you were building it."

"Tell me."

"Abeyance of the determination doesn't stop the Survey," said Camila, "because the Survey isn't a Programme instrument. It isn't an observance, it isn't a communication, it isn't a Milestone. It's a certification activity, initiated at grade level, running on work orders. There are nine hundred people a day filing paper into a queue that Programme has no standing in whatsoever. And the only way to stop it is to instruct four hundred grades to stop recertifying their own equipment, which is an instruction no office aboard this ship has the authority to give, and which the first person to receive it would put on a public terminal inside eleven minutes." She got the door open. "Hands do what the paperwork says. It cuts both ways and nobody noticed, because for ninety years it only ever had to cut one."

She stopped in the doorway.

"They'll come at you instead," she said. "That's the fallback and it's already been raised. Not a P-7 — your panel returned the file to the tray on the fifteenth, did you know that?"

"Yusuf told me. There's no outcome code, so they invented one. No determination — see also 80/D/1."

"Yes, well, they've stopped trying to make you ill. Now they're going to try to make you singular." Camila's face was very tired and very clear. "The line in the room this morning was: this is one technician's interpretation. They'll say it kindly, in an appendix, for the next forty years. One woman, one channel, one night, one loupe."

"Then it's a good thing," said Sol, "that I'm going outside tomorrow at 0400 to bring back a piece of the ship."

They gave her three days, which was two more than the guild wanted and eleven fewer than the standing instruction required, and Chief Adaeze Ekwueme-Strand signed the waiver herself in green ink and wrote across the bottom of it, in her own hand: Restricted: tethered, tended, no independent manoeuvre, no tool exchange, escort to remain within two metres at all times. She is going out as a pair of eyes and a loupe and I will have her back inside the hour and a half or I will come out myself and get her.

Teo drilled her in the Frame 9 vestibule for eleven hours across the sixteenth, seventeenth and eighteenth, and it was the least mysterious experience of Sol's life, which she came to understand was the point. He taught her the neck ring and the wrist rings and the glove seat. He taught her the four things that kill people, in order, and made her say them back until she was bored. He taught her to breathe out on the way through the hatch. He taught her that a tether is not a safety line, it is a route, and that she would want to look up and that if she looked up she would be looking at nothing and would lose four minutes getting her stomach back, and that she was not to look up until he told her to, and that he would tell her, and that when he did she should hold the handrail with both hands and not let go for anything at all.

"And the ninetieth minute," said Sol.

He stopped.

"Who told you about the ninetieth minute?"

"A woman with forty-one of them."

"Then she'll have told you your hands go." Teo held up his own, flexing them in the liner. "It isn't cold and it isn't fear, it's the glove. Ninety minutes of gripping against pressure and your forearms are done, and the last thing anybody does on any EVA is the thing that needs a grip, and that's when they drop it." He looked at her. "That's when he dropped it."

"You don't know that."

"No," said Teo. "I don't know that."

Kemi Odeleye-Vance came down on the seventeenth and ran the checklist with them, all eleven pages, because she had run it forty-one times herself and there was nobody aboard who had run it more recently. She did it without a word of apology and without one flicker of proprietorship, and when they got to the tether inspection she pulled the whole eighty metres of line through her hands, hand over hand, on her knees on the vestibule deck, looking at it, which was not on the checklist.

"They taught us to do that at Six," she said, when she noticed Sol watching. "It isn't in the standing instruction because you can't write it down. You just — " she shrugged, still going, hand over hand — "you put your hands on all of it. All of it. Every time."

"Who taught you?"

"Ruy. And a man called Adeyemi-Løkke taught Ruy." Her hands did not stop. "He was on the detachment until Y74 and then he went to gauges because his knees went, and he came back twice a year for the drill anyway, and we called him Uncle, and I got a note from his daughter at six o'clock this morning."

Sol did not say anything. There was nothing that was not an insult.

"I've thought about whether to say this to you," said Kemi, "and I've decided I will, and then I won't say it again." She reached the end of the line and sat back on her heels. "I don't blame you. I want you to know that so you don't spend tomorrow managing it. Ruy blames you. Two of the four at Six blame you and they are going to blame you for the rest of their lives and they are entitled to." She stood up and coiled the tether onto its rack, neatly, in eleven turns. "But I maintained that machine since I was twenty-one and Uncle Rufino gauged those tanks for thirty-eight years, and the difference between us is nine days and a woman with a loupe, and if you had not come through that plate on the eleventh then in about four years it would have been me sitting down in a purge line and nobody would have had the first idea why."

At 0342 on the nineteenth the vestibule at Frame 9 was more crowded than it had been at any time since Y69.

Chief Ekwueme-Strand had the board. Merced had the comms and the log. Jae had a slate and a camera and the fixed, glassy expression of a woman running on her fourth consecutive night. Kemi and Ruy Ferrão stood the tether rack, and Ruy did not look at Sol, and did his job perfectly. Naveen Duarte-Chatterjee had come up from Frame 35 in a coverall that had never been forward of Frame 20 in its life, and had said, when Sol raised an eyebrow, "I signed it. A man should look at what he signs," and then had spent an hour standing out of everybody's way with his hands behind his back like a father at a school event.

And in the corner, on a folding stool, wrapped in a blanket, with an oxygen cannula under her nose and an orderly from Frame 12 standing beside her looking as though he had been abducted, was Bett Osei.

"Don't," said Bett, when Sol came over. "Don't say one word. Thea Marchetti-Owusu signed a movement authority at midnight and I have never in my life been carried anywhere and I would like it noted that I walked the last forty metres."

"She did not walk the last forty metres," said the orderly.

"I walked eleven of them."

Sol crouched in front of her.

"Say it," she said. "The thing you were going to say. Say it now so I've got it out there."

Bett Osei looked at her with her one good ear turned in and her enormous ruined hands flat on the blanket.

"You're going to want to hurry at the end," she said. "Everybody does. You'll get the thing done and you'll look at the clock and you'll think, I have twenty minutes, I'll just — and that's the sentence. I'll just. Forty-one times I went out and forty-one times I thought it, and the only reason I'm sitting here at eighty-six is that I had a teacher who made me say no out loud into the loop when I thought it." She reached up and got hold of Sol's wrist through the liner. "Out loud. Into the loop. So there's a recording of you refusing."

"All right."

"Say it now. Practise."

"No," said Sol, into the vestibule, to nobody, and eleven people looked round, and Bett let go of her wrist and sat back, satisfied, and closed her eyes.

At 0359 Merced said, "Board's green, chief," and Chief Adaeze Ekwueme-Strand said, "Log it," and Merced logged it: 0400. Rosette 3 coupon recovery and first-surface inspection, WO-8S-0519-1 and WO-14C-0502-1. Egress two: AMARAL-KWAN, T., Structures IV, lead. IBARRA-NAKASHIMA, M., Optical IV, restricted ticket, tended. Frame 9 lock. First guild egress since Y69/07.

The chief put her scarred hand flat on the lock door for a moment, the way you touch a horse.

"Forty-second consecutive," she said. "Go on. Get out of my ship."

The lock cycled in four minutes and eleven seconds and Sol spent all of it breathing the way Teo had taught her and thinking, with the small hysterical part of her brain that would not shut up, about Hana Petrossian-Bright, who had gone out through this door in the autumn of Y71 without a suit and whose file said hypoxic event, and about how nobody had ever put a plaque on it, and how she was going to fix that.

Then the outer door opened and there was no floor.

She had been told. Teo had told her eleven times and had made her repeat it: the first four seconds are the worst four seconds and they are not dangerous, they are just the worst. And it was true, and it did not help, and she came out onto the exterior rail with her heart going like a pump with air in it and her eyes fixed on the hull thirty centimetres in front of her face, which was grey, and pitted, and welded, and ordinary, and which she loved with a violence that frightened her.

"Sol. Voice."

"Here."

"Say the four things."

She said the four things.

"Good. Clip and confirm."

She clipped and confirmed, and Teo came out behind her, and the tether went out from the rack in Kemi's hands eighty metres aft, and they began to move.

It took thirty-eight minutes to go forward along the flank of the Anabasis, hand over hand, on a run of yellow-painted rail that Structures had inspected in Y69 and had not touched since, and it was the most boring thing Sol had ever done. That was the second surprise. There was no sensation of speed, because there was no speed to sense; there was no wind and no sound but her own breathing and Merced's voice reading the clock every two minutes; there was only a grey plain of hull going by under her gloves at the pace of a woman walking up a ladder in no gravity, panel after panel, seam after seam, the odd stencil, the odd old repair with a different grey to it.

At the twenty-minute mark, Teo said, "Stop. Both hands on the rail. Both. Now look up."

Sol looked up.

She had been forty-one years old for four months and she had never seen a sky that was not a rendering.

The renderings had been beautiful. They were in the Bowl on festival nights and in the school at Frame 24 and on the deckhead of the Grove: deep velvet blacks and a wash of stars in blue and gold with a drift to them, and a little glow around the bright ones, and the sense — always the sense — of enormous depth, of near and far, of a room you could walk into.

There was no depth. That was the first thing and it went into her like cold water. There was nothing to tell her what was near and what was far, and so it was all at exactly the same distance, which was no distance, which was the inside of her own eyes. It was not a room. It was a surface, and it was black, and it was harder and blacker than any black in her life had prepared her for, and it was absolutely thick with points of light that did not move, did not twinkle, did not drift, did not do one single thing, and would not, for the rest of her life, or her nephew's, or his.

And it was still. That was the thing that took her legs, or would have if she had had any use for legs. Nine thousand people two kilometres behind her were being told this week that the ship was not going where they had been told it was going, and the argument was rising through the Ribs like weather, and out here there was a two-kilometre spindle hanging in front of a wall of unmoving light at seven hundred and fifty kilometres a second and nothing was happening. Nothing had happened for eighty years. Nothing would happen for four hundred more.

"Optical," said Teo, quietly, on the loop. "Talk to me."

"I'm here."

"Say something true."

"It isn't beautiful," said Sol. "No."

"It's flat. There's no distance in it. In the Bowl they give it depth, they put the bright ones forward, there's a — " she heard her own breath in the helmet and made it slow down — "there's a haze round them, you feel like you could go in. There's nothing to go into. It's a wall with holes in it."

"That's what I said the first time," said Teo. "Twenty-seven years old, hanging off the rail crying like an idiot, and Ansel said give it three minutes."

"Why three minutes?"

"Because in three minutes you stop looking at all of it," said Teo, "and start looking at one."

Sol hung on the rail with both hands and gave it three minutes, and Merced read the clock twice into the loop from a room she could no longer imagine, and slowly, the way an eye finds a fault in a weld, she began to find her way around a sky she had known by coordinate for nineteen years and had never once seen.

She had the numbers. That was the absurdity of it; she had had the numbers since she was twenty-two. Channel Fourteen's field, the four reference targets, the position angles she could have drawn on a napkin. She looked twenty degrees off the spindle axis, and down, and there it was: unremarkable, small, the colour of a low lamp seen through a doorway, sitting in a scatter of nothing, and it was not flickering, because a human eye is a poor photometer and because at that moment it was doing nothing at all.

The Lantern.

Nineteen years. Forty nights of a recording. A grey box on three thumbscrews.

"Teo."

"I see you looking. Which one?"

"Twenty degrees off the axis, down, on its own, orange."

"That's yours?"

"That's mine," said Sol, and did not trust herself with anything else, and went back to the rail and to the next panel and the next seam, hand over hand, forward.

The Cap came up over the curve of the hull the way a hill comes up: not as an object but as an end to things. The rail ran up onto its aft face and Sol pulled herself over the shoulder of it and stopped.

Three hundred tonnes of stuff whose entire purpose was to be destroyed slowly and on schedule.

It was intact.

Not clean — nothing that had been in a vacuum for eighty years was clean; there was a faint mottling, a grey-on-grey, from the interstellar hydrogen coming through at a fortieth of light and doing, patiently, over eight decades, what a puff of breath does to a mirror. Sol had expected pitting she could see from four metres. She had expected the leading edges of the plate stack to be rounded, sagged, chewed, a thing that made you understand at once why it was called sacrificial.

The edges were square. Every one of them was square, the way a fabricator leaves an edge, and the plate faces were flat, and where the yard had ground a weld flush in a shed on Phobos eighty-one years ago, you could still see the swirl of the disc.

"Say it," said Teo, on the loop. His voice had gone thick.

"There's no dust on it," said Sol.

Nobody in the vestibule said anything for a long moment. Then Merced, very steady, very level: "0431. Egress two at the Cap face. Statement recorded."

Rosette 3 was a pad and a frame: a flat plate a metre square with a low kerb, four foot restraints, a grab bar, and mounted on a swivel a rosette of sixteen coupon seats arranged like the petals of a paper flower, each with its captive clamp and its stamped number.

Twelve of the seats were empty.

Four were filled, and their clamps were closed, and the little brass tag riveted to the swivel said, in stamped figures worn but perfectly legible: SEATED Y69/03 — A.F-S. / T.A-K. / M.O.

Teo went very still on the rail.

"Spring swap," he said. "We seated those in the third month. He was going to pull them in the seventh."

Eleven years and two months of exposure. Sol got herself into the foot restraints — badly, twice, and Teo waited without a word — and put her helmet as close to the rosette as the visor would allow, and turned her lamp down to its narrow beam, and looked.

Under a suit lamp at half a metre, a real coupon looks like a small grey moon. That was what she had been taught. That was Bett Osei's hand on her shoulder at twenty-two and a coupon out of the Y58 archive going round the bench at Frame 38 while eleven apprentices said oh.

These four had a bloom on them, the softest possible frosting, like the ghost a cold cup leaves on a table. And in the middle of the second one, at about ten o'clock from centre, was a single crater she could see with her naked eye: a real one, a proper one, with a raised lip and a spatter apron and a shattered zone around it, one grain of the actual universe arriving at seven hundred and fifty kilometres a second and being, briefly, a star.

One. In eleven years.

Sol got the loupe out — it was on a lanyard, it had been on a lanyard for three days at Teo's insistence, and she understood the lanyard now with her forearms already beginning to complain — and she put twelve magnifications on it and looked into the mirror-polish between the craters and saw, going down and down past the limit of the glass, smaller and smaller and more and more numerous, exactly what a fractal mess looks like: pits at every scale, no floor, no lip, no rivet-set, no specification.

Real.

"Optical." Merced's voice. "You've gone quiet. Say a number."

"Four seated in Y69 month three," said Sol. "Eleven years two months exposure. Visible macro-craters, one on coupon two, one — no, two on coupon four. Micro-pitting continuous to the limit of my glass with no floor. Frosting is — " she made herself say it in units — "call it a haze, not a velvet. Chief, I'd estimate by eye that these have taken less erosion in eleven years than the Y80 rack coupon shows for six months."

There was a pause of perhaps four seconds.

"Say that in a way I can put on my wall," said Chief Ekwueme-Strand.

"By eye, two orders of magnitude low," said Sol. "Weigh them and I'll give you the real one."

"Pull them," said the chief. "All four. Tag and bag."

Teo pulled them, because Teo had a full ticket and a grip, and Sol held the bag, and it took eleven minutes, because the clamps had been closed by a man's hands in the third month of Y69 and had been sitting in vacuum ever since, and each one had to be worked.

On the third clamp Teo stopped.

"Sol."

He was looking at the underside of the swivel, at the kerb where the frame met the pad, where a person standing in the foot restraints would have their thigh against the metal and where anybody with a free-floating tool would clip it to be rid of it for ninety seconds.

There was a lanyard loop on the kerb cleat, and on the loop, hanging in the dark exactly where it had been left, was a loupe.

Not floating. Not drifting. Clipped, and hanging perfectly still, the way everything out here hung perfectly still, because there was no air and no gravity worth the name and nothing at all had happened here in eleven years.

Sol looked at it for a long time.

"That's his mother's," she said.

"He clipped it," said Teo, and his voice came apart in the middle of the word and came back. "He clipped it off to work the clamp. That's — you clip it off to work a clamp, that's what you do, you don't work a clamp with a glass swinging on your chest — and then his regulator — "

"Teo."

"He clipped it off to work a clamp."

"Teo. Both hands on the rail."

There was a silence of about eleven seconds on the loop, and then Merced said, very quietly, "0459," and logged nothing else.

Sol did not take the loupe. She thought about it — she thought about the Councilwoman's hand and the thing you can hold — and then she thought about a man who had planned it for two years and had come out here to get a piece of metal, and she left his glass hanging on its cleat where he had put it, and she photographed it four times at two exposures with the film camera bolted to her chest plate, and she said, into the loop, for the recording:

"Item at Rosette 3 kerb cleat, hand loupe on lanyard, left in situ, photographed. It stays. That's not evidence, that's a man's tool where he put it, and the next crew can look at it."

The cut took twenty-two minutes.

Teo did it four metres inboard of the aperture line, where the first surface was virgin plate and where the little square he was taking would sit in the shadow of an edge that was already there — the geometry Sol had done nine days ago at a bench, on paper, in order to have an answer that was not please. He scribed it, and drilled the corner reliefs, and cut it with a battery saw whose blade threw no sparks at all in vacuum but only a slow spreading fan of grey chips that went away in straight lines forever, and Sol watched them go and thought: those are ours now. Those are the first things this ship has ever put out into the universe on purpose.

The plate came free.

Sixty millimetres by sixty by six. Teo took it out of the hole with two fingers and a thumb and turned it over once and put it into the bag Sol held open, and neither of them said anything, because there was nothing to say about it and because it was, in the end, a piece of metal.

"Bagged and tagged, 80-0119," said Sol. "First-surface witness section, adjacent Aperture Fourteen, cut face down, exposed face up, chain of custody Amaral-Kwan to Ibarra-Nakashima at 0524."

"Copy," said Merced. "0524. You're at seventy-nine minutes."

And there it was.

The hatch was six metres away.

She could see it from where she stood in the foot restraints, and she had not looked at it once in fifty minutes, because she had known it was there and had known what would happen if she looked at it: a rectangle of newer plate let into the face of the Cap, with a dog-latch and a suit-glove handle and a scuffed pad below it where sixty-one years of knees had gone, and it was the whole thing, it was the entire machine, it was the door the story came through twice a year, and there was not a photograph of it in existence taken from outside.

Six metres. Two minutes on the rail. Four exposures.

Her forearms were burning in a way she had never experienced and her hands, when she thought about her hands, were doing about seventy percent of what she asked them to do, and the clock said seventy-nine minutes, and there was a whole hour of transit still to make.

I'll just.

Sol heard it arrive in her own head in her own voice, sweet and reasonable and helpful, exactly as an old woman on a folding stool in a blanket had said it would.

"No," she said, out loud, into the loop.

"Say again, Optical?"

"No," said Sol. "Recording it. I want to go six metres to the gallery hatch and photograph it and I have decided not to. Time 0526. My hands are at about seventy percent and I have transit to make. Somebody else can get that picture next month."

There was a small sound on the loop that might have been Merced and might have been the chief.

"I'll get it," said Teo. "Full ticket, my hands are fine, I'm two metres up the rail from it, it's forty seconds."

"Teo — "

"That's not I'll just," said Teo. "That's a competent man taking four exposures on a rail he's clipped to with eleven minutes of margin, and I've been paying out somebody else's line since I was twenty-seven and I would like, once, to bring something back." A pause. "Chief?"

"Take the pictures," said Adaeze Ekwueme-Strand. "Four exposures. Then get my people home."

The ninetieth minute was exactly what she had been told it would be.

Sol came down the rail on the return transit hand over hand with her forearms full of hot wire and her fingers curling shut on their own, and discovered that Bett had understated it, and that the reason the old woman had understated it was that there is no way to say your hands stop being yours to somebody who has not had it happen.

At the lock she got the bag off her chest harness and could not make her hand open.

She hung there with eighty years of the front of the ship in her fist and a grip she could not release, and Kemi Odeleye-Vance came halfway out of the lock on a short tether and put both of her gloves around Sol's glove and said, on the loop, in the flat voice of a technician doing a custody transfer:

"Kemi Odeleye-Vance, TA maintenance detachment, receiving bag 80-0119 and bag 80-0120 from Ibarra-Nakashima, Optical, at 0631. I have it. You can let go now. I have it."

"You have it."

"I have it. Let go."

Sol let go.

The guild weighed the coupons at 1140 that morning, in the shop at Frame 8, on a balance that Folasade Ekwueme's people had built in a shed on Phobos and that had been calibrated every quarter for a hundred and eleven years by a succession of women who did not trust anybody.

They did it in front of everybody. That was the chief's decision and she made it out loud: the shop floor cleared, the benches shut down, thirty-one members of Forward Structures standing around a balance table with the hard white light on, plus a Registrar, plus an astrometrist, plus a keyworker from Frame 19 whom nobody had invited and nobody asked to leave, plus a schoolteacher from Frame 24 named Ify Aduba who had written a curriculum query and had been told, by return, to come and see for herself.

Merced ran the balance because Merced was the best hand in the shop.

"Coupon one. Seat four. Seated Y69, month three. Exposure eleven years two months." She set it in the pan with tweezers. "Nominal seated mass, one hundred and four point one one one grams, from the Y69 seating record in the chief's log."

She read the number off the balance three times before she said it.

"One hundred and four point one zero eight."

The shop was quite silent.

"Mass loss over eleven years and two months," said Merced. "Three milligrams."

Chief Adaeze Ekwueme-Strand stood with her arms folded and her scarred hand tucked into her elbow.

"Predicted," she said.

Merced did not need to look it up, and did not look it up, and everybody in that shop knew she did not need to.

"Off my great-great-aunt's curve, at book flux? One hundred and eleven milligrams a year." She swallowed. "Twelve hundred and thirty milligrams over the exposure. We got three."

"Ratio."

"Four hundred and ten to one," said Merced.

Somebody at the back of the shop said, "Christ," and somebody else told them to shut up, and then nobody said anything for a long time while Merced weighed the second one, and the third, and the fourth, and wrote each number in ink in the chief's log with the date and her own initials beside it, and got four numbers that agreed with each other to within the resolution of a hundred-and-eleven-year-old balance.

Jae did the arithmetic standing at the end of the bench with a slate.

"That's a flux ratio, not a velocity ratio," she said. "Impact rate goes as velocity and mass loss goes roughly as velocity squared through the erosion yield, so — " she stopped, and did it again, and Sol watched a woman deliberately slow herself down in front of thirty-one witnesses — "four hundred and ten to one in mass loss puts the velocity ratio between a fortieth and a fiftieth of book. Which agrees with the acoustic integration to within the error bars on both, and the two methods share no assumption but the dust density."

"Say it in one sentence," said the chief. "For my wall."

Jae looked up.

"Two independent physical measurements, made by two different grades using two different instruments, agree that this ship is travelling at approximately one fortieth of the speed on which its schedule is based."

Chief Ekwueme-Strand nodded once.

Then she went and got the rolling ladder.

The wall of Forward Structures held a hundred and eleven years of hand-plotted erosion charts in a column going up from the deck: brown ink at the bottom, black at the top, one sheet per year, initialled by the chief of the day. The chief carried a fresh blank sheet up the ladder and pinned it at the top of the column in the place where Y80's sheet belonged, and then came down and stood looking at it with her hands on her hips.

"Merced. Plot it."

Merced went up with a fine nib and the log, and put the axes on, and the fitted line from the previous decade, and then went to place a single point at eleven years two months, three milligrams.

She stopped. She looked down at the chief.

"It's off the sheet," she said. "Chief, at this scale it's — it's below the bottom edge. It's not on the paper."

"Then get more paper," said the chief.

So they taped a second sheet under the first, and Merced put the point on it, low down, alone, a single dot of black ink four hundred millimetres below the fitted line that eighty years of scattered honest points had climbed the wall towards; and Chief Adaeze Ekwueme-Strand went back up the ladder and wrote the date across the top of the upper sheet in her own hand and initialled it, and then came down and wrote, along the bottom of the lower one, in letters a hundred millimetres high, the only annotation ever made on that wall by any chief in a hundred and eleven years that was not a number:

Y69–Y80. FOUR COUPONS. SEATED BY A. FERREIRA-SUNQUIST, T. AMARAL-KWAN, M. OSHIRO. RECOVERED 19/5/Y80. THE COLUMN GOES DOWN FROM HERE.

Bett Osei died on the twenty-ninth of the fifth month of Year 80, in her chair, in the afternoon, ten days after Sol brought her the plate.

She had held it for most of an hour. She had not talked much. She had turned it over and over in her enormous ruined hands — sixty by sixty by six, one face rough with the swirl of a cutting disc, the other faintly, softly hazed, like the ghost a cold cup leaves on a table — and she had put her thumb across the exposed face and rubbed it, back and forth, the way you test a surface, and she had said, once:

"Eighty years."

"Eighty-one," said Sol.

"Eighty-one years out in it, and I can feel the mill marks." Bett laughed her terrible three-note laugh and did not cough. "Girl. I can feel the mill marks."

Sol had asked her, at the end, whether she wanted anything said. Bett had considered it for a while with her one good ear turned into the sun of the grow-lamps.

"Put my nitrogen study on the board," she said, "which you've done. Put my name on the top of it, which you've done. And when they ask you at some committee in eleven years' time who worked it out — " she got hold of Sol's wrist one last time, conduit under lagging — "you tell them a Structures woman heard three ticks in a minute in Y72 and did nothing about it for twenty-eight years, and then a hull tech came and sat on that stool, and the thing that mattered was not the hearing. Everybody hears. Six of us heard. The thing that mattered was that somebody finally wrote it on a form."

They committed her to the Grove on the second of the sixth month, and Forward Structures came, all thirty-one of them, and stood at the back and did not say anything, because she had been Optical and there were limits.

Sol carried the plate to the service, in the bag, with the custody tag on it, because it was evidence and could not be given away.

Afterwards she took it back to Frame 38 and put it on the bench under the yellowed lamp, and sat down, and looked at it for a long while, and then got out the loupe and looked at it properly, going down and down past the limit of the glass into a fractal mess of real, honest, unbudgeted damage, no floor, no rivet-lips, no specification: eighty-one years of the actual universe arriving one grain at a time on the front of a house.

The board in the Bowl said PROVISIONAL that morning in type the same height as the figure it qualified. The Mood Index stood at 4.9. There were sixty-one open P-7s and a working group and an argument in the Council of Ribs that had been running for eleven days and would run for another four hundred. Somewhere at Frame 31 a woman who ran a laundry had filed her ninth recertification, and somewhere at Frame 24 a schoolteacher was standing in front of a class of eight-year-olds telling them that the animation was wrong, that the Cap was cold and grey and did not glow, and that this was the first thing anybody had ever learned about it by going and looking.

And out at the front, forty metres of walkway stood lit and railed and entered on the maintenance set, with twelve bays stencilled in fresh white paint and eleven blanks still bolted over eleven slits, waiting for eleven work orders, which would take, at the pace at which real work gets done aboard a ship, most of a year.

Sol put the plate down and pulled her slate over and opened WO-14C-0502-1, and went to the box at the bottom that had been empty since the second of the fifth month, the one marked CLOSING REMARKS — RESPONSIBLE GRADE.

She thought for a while.

Then she wrote: Fault confirmed by physical measurement. Cause traced. Corrective action ongoing and will outlive the originator. Recommend this order remain open.

She thumbed it, and filed it, and got up to go forward, because it was 0212 and Channel Fourteen wanted its certificate back, and there was nobody else on the shift.

On the eleventh of the sixth month of Year 80 the Bell rang at 0630, one note, low, out of the deckheads, and nine thousand people felt their chests loosen, and then nothing happened.

That was the thing nobody had prepared for, and Camila had known it was coming and had put a line in her own working group's minutes about it eleven days in advance, and had still not prepared for it. The absence had a shape. For sixty-one years the note had been followed, at a count of four, by a long soft shove that came up through the deck into the soles of your feet, and now the note was followed by a count of four and then by a floor that stayed exactly where it was. Children who had put cups of water out the night before stood over them and watched the meniscus not move. In the Bowl, two hundred people who had come out of habit stood in the Highland wash with their hands on the rail, waiting, and went on waiting past any reasonable time, and one woman began to cry and could not have told anybody why.

Sol felt it at Frame 38 with a cryo fitting in her hand, and set the fitting down, and stood with her palm flat on the bench, and thought: that is four hundred and six kilograms we still have.

The Council of Ribs met at 0900.

They met in the chamber off the Bowl at Frame 31, which had twenty-two seats in a shallow curve and a public gallery behind a rail that had, in living memory, held perhaps eleven people on a busy day and which held, that morning, two hundred and forty, with a queue on the stairs and Merced Ekwueme-Strand at the back holding the door open with her boot so the ones on the stairs could hear.

The Programme went first, because the abeyance motion was theirs.

Director Halim Osegueda-Ferrer was sixty-four and had run the Programme since Y70 and had, in that decade, presided over the highest sustained Mood Index in the ship's history, and Sol, watching him take the floor, understood within four sentences that Bett had been right about the danger of thinking these people stupid, and that Camila had been right about the danger of thinking them wicked.

He did not dispute the determination. He said so at once, in his first minute, in the flattest possible language: the Registrar's finding was within her authority and rested on physical evidence the Programme had no competence to assess and no wish to contest. He said that the Programme had been wrong for ninety years, and that he personally had been wrong for ten, and that he would not be resigning today because resigning today was an act of self-care disguised as accountability and there was work to do.

Then he asked for ninety days.

"Not to reconsider," he said. "Not to soften anything. Ninety days in which the determination stands, the Survey continues, the Trust publishes whatever it likes, and this Council does not put a question to the Bowl. Ninety days to build the thing people will stand on before we ask them to stand on it." He put both hands on the rail of the speaking place. "I have the Cerro figures in front of me and I am not going to read them out, because reading them out is a rhetorical act and there are two hundred and forty people in that gallery. I will say only that in the eleventh year of the Cerro's voyage, a truth was told in a hurry by people who were entirely correct, and eleven percent of her complement was dead within a year, and she is still out there, and nobody has heard from her since Y41."

He sat down. Nobody made a sound.

Camila spoke second, because the Programme's assessment was hers to present, and she was thirty-eight years old and she had not slept properly in a month and she put a single sheet of flimsy on the rail in front of her and did not look at it once.

"Chair. The Continuity assessment is nineteen pages and it's on the public board since 0600 and I'd ask that it be taken as read." She waited for the nod. "I'm required to give the Council the current figures, and I'm going to do that, and then I'm going to say one thing that is not in the assessment, and my Director knows I'm going to say it, and he has not asked me not to, and I'd like that in the minutes."

"It's in the minutes," said the Chair.

"Mood Index this morning, four point four. Open P-7 referrals, sixty-eight. Sleep-aid dispensing up four hundred and ten percent on the month. Absence from shift up eleven percent, and I'd note for the Council that most of that absence is people going and looking at their own equipment, which does not show up anywhere as work." Camila's voice was absolutely steady. "Since the twelfth of the fifth month there have been seven deaths by self-administration aboard this ship. In the same period of last year there was one. I am going to read the names, because it is the last thing my office is going to be permitted to do quietly and I would rather do it loudly."

She read them. It took forty seconds. Rufino Adeyemi-Løkke was the first and a woman of eighty-one from the Long Rib was the fourth and a nineteen-year-old apprentice from Hydroponics was the seventh, and the gallery made no noise at all except, near the end, one sound from somewhere at the back that had a name in it.

"That's the bill so far," said Camila. "It is going to get worse before the winter. Every projection I have says worse, and every projection I have was built by people who were assuming they'd be managing a Milestone, and I don't trust any of them past ninety days, and neither should you."

She let that sit.

"And now the thing that isn't in the assessment," she said. "I'm going to advise this Council against my Director's motion, and I want to be precise about why, because he is right about everything except the mechanism."

There was a small movement along the curve of seats.

"Ninety days doesn't buy what he thinks it buys. There is nothing to build in ninety days, because the thing people need to stand on is not a communication. I've been in Observances for nine years and I have written four hundred communications and not one of them has ever held anybody's weight for longer than a Milestone." She picked the flimsy up at last and turned it over and put it face down. "The only structure I've seen hold weight in the last month is work. On the twelfth of the fifth, a woman at Frame 31 who runs a laundry press filed a recertification on her own machine, unprompted, at ten past six in the morning, and wrote in the reason field because I was told to look at my own bench first. There were eleven filings that day. There were nine hundred and forty yesterday. Sixty-eight people are in category seven and about four thousand are in a shop somewhere arguing with a stores clerk about interlayer creep, and I would ask the Council to notice that those are not the same four thousand people, and that the second number is why the first one isn't larger."

"You're saying the Survey is holding it up," said a councillor.

"I'm saying the Survey is the only thing holding it up, and that it is being held up by nine hundred people a day who have not been told what to think and have therefore not had anything taken away from them," said Camila. "A person who has worked out a terrible thing at their own bench with their own hands is standing on something. A person who has been informed of it in a well-drafted paragraph by my office is standing on my office. There are nine thousand of them and there are forty of us and we will not bear it. We have never borne it. We have only ever been standing on the schedule, the same as everybody else, and the schedule has gone."

She sat down. Osegueda-Ferrer, four seats along, reached over and put his hand briefly on her forearm, which Sol, from the gallery rail, thought was either the kindest or the most professional thing she had ever seen a man do in public, and probably both, and probably that was the whole story of the Programme.

Then they called the Registrar, and then they called Chief Ekwueme-Strand, and then, at 1104, they called Sol.

The attack, when it came, was not an attack. That was the last thing she learned about them, and she thought afterwards that she should have known it from the beginning, because she had been told, in one way or another, by everybody: there is no room full of men with a list.

Councillor Tobias Iwu-Grenfell, Ribs Four, second term, forty-five years old, a decent man with a decent record, asked his question in a tone of open sympathy.

"Ms. Ibarra-Nakashima, before anything else — on behalf of my constituency I'd like to say that whatever this Council decides today, what you did in the fourth and fifth months of this year was extraordinary, and it appears to have been right, and I don't want that lost in what I'm about to ask."

"Thank you, Councillor."

"My difficulty is this." He turned a page he did not need to turn. "Everything before us today comes back to one person's judgement on one night. One channel. One technician. One pattern noticed in a recording, by a woman who by her own account had been awake for fourteen hours, and who then — and I say this with respect — spent nine days assembling a case in support of it. That's not a criticism. That's how anybody would behave. But the Trust's determination, and the Structures finding, and the Nav note, and the Survey, and this Council's whole agenda, are all downstream of a single interpretive act by a single individual." He spread his hands. "How do we know we are not, all of us, nine thousand of us, downstream of one tired woman who heard a rhythm?"

The chamber went very quiet.

Sol had rehearsed eleven answers on the walk down and she used none of them. She reached into the stores bag at her feet and took out two objects and set them on the rail of the speaking place, side by side.

"Councillor, I'm going to ask the Chair's leave to pass two things round the table, and to hand up a third to the gallery, and I'd like to say nothing at all while it happens, because everything I say from here is exactly the problem you've correctly identified."

The Chair looked down the table, and got nothing back, and said, "Leave granted."

"On the left is witness coupon Y80-1," said Sol. "It came out of the rack in the forward vestibule where Forward Structures has racked coupons twice a year since Departure. It is in Trust custody, tag 80-0031, and it is the object on which the entire ablation basis of this ship has rested for thirty years. On the right is a piece of the front of this ship. It's sixty millimetres by sixty by six. It was cut off the first surface of the Bow Cap four metres inboard of Aperture Fourteen at 0524 on the nineteenth of the fifth month by Teodoro Amaral-Kwan, Structures Four, in my presence, and it has been out in it since the yard at Phobos closed it out eighty-one years ago." She put a loupe down between them. "One of these has been in a sandstorm for eighty-one years. The other has been shot with iron dust by a machine at Frame Six to a specification with a resolution limit. Twelve magnifications. Look at the small craters. Go down in size until they stop. On one of them they don't stop."

She stepped back from the rail.

"That's all. I'm not going to answer any more questions until it's gone round."

It took twenty-six minutes.

Councillor Iwu-Grenfell went first, because he had asked, and he did it properly, at the lamp, for a long time, and when he had done it he did not say anything, and passed both objects to his left and then sat looking at his own hands.

Sol stood at the speaking place with her arms at her sides and watched twenty-two elected representatives of nine thousand people hand two pieces of metal along a curved table, and she thought about a man of twenty-one in Y52 with a loupe his mother had given him because he thought it made him look serious, who had gone four years believing he was ill, and who had worked out — alone, with nobody to ask — that nobody argues with a thing you can hold, and had died at a rosette six metres from a hatch, trying to get one.

She had said so, upstairs, to the Chair, before the session, and the Chair had asked whether she wanted it read into the record, and she had said no. It would keep. It would keep for eleven years if necessary. It was not a card to be played; it was a debt to be paid slowly, in files, with the correct references.

At the eleventh seat, a very old woman took the loupe and looked, and put it down, and did not pass the coupons on.

"Chair," said Councillor Ines Sorrentino-Mbeki, Ribs Two, seventy-three years old, in her ninth term. "I'd like the record to show that I am holding these for a moment."

"Noted."

"Ms. Ibarra-Nakashima. In Y74 a woman came to me with a case." Her voice was very dry and did not shake at all. "Nadia Okonkwo-Reyes. Propellant archivist. We were at school together at Frame 27; she was better at everything than I was except talking. She sat in my berth for an hour and a half with a folder and she told me that this ship was not moving as we had been told, and she had it in order, and she had done the arithmetic, and she was frightened, and she asked me to believe her." She put her hand flat on the table beside the two coupons. "I filed a wellbeing referral. Category seven. I did it that evening, and I did it because I loved her, and I have never for one day since believed that I did anything other than my duty as I understood it, and I have thought about her at least once a week for six years since she died."

The chamber did not move.

"I am not going to tell this Council how to vote on the Director's motion. I have a different motion and I will bring it after." Councillor Sorrentino-Mbeki pushed the coupons and the loupe on to her left. "But I want two things minuted. The first is that the care taxonomy of this ship contains no outcome code for a category seven referral in which the subject was correct, and that this is not an oversight, it is a design, and I would like one made, and I would like Nadia's file re-coded under it and her family told, in person, by me."

"So minuted," said the Chair, after a moment.

"The second," said the old woman, "is a question for the technician, and it isn't a hostile one, and she may take her time."

"Ask it," said Sol.

"You had nine days. You could have come to a member of this Council. You could have come to me — I'm on the public list, my berth is at Frame 30, anybody can knock." Councillor Sorrentino-Mbeki looked up at her. "You didn't. You went to a chief of Structures and a girl in Nav and a keyworker and a maintenance technician of twenty-four, and you filed a work order about a chamfer. Why did you not come to us?"

Sol thought about lying to her, and did not, because the woman had just done the hardest thing anyone had done in that room.

"Because I knew what happened to Nadia," she said, "and I knew who filed it, and I knew it wasn't cruelty, and I worked out that if I came to this Council as a person asking to be believed, then the most likely outcome in the world was that somebody decent would be worried about me." She kept her eyes on the old woman's. "So I went to the people who could put their hands on the metal. Not because they're better. Because the metal doesn't need anybody's belief. Councillor, I want to be honest with you in front of two hundred and forty people: I did not trust this Council, and I was right not to, and the reason I was right is not that you are bad. It's that this ship has spent ninety years building a very kind machine for converting a true statement into a symptom, and every one of us is a part of it, and you were the part that touched Nadia."

Councillor Ines Sorrentino-Mbeki nodded slowly, twice.

"Yes," she said. "That's what I thought it was."

The Director's motion for abeyance was put at 1240 and was defeated fifteen to seven, and the seven were not cowards and said so in their explanations of vote, and one of them, a young member from Ribs Six, said the only thing anybody remembered afterwards, which was: I am voting for ninety days because I have a daughter of eleven and I do not know how to tell her, and I am aware that this is not a reason, and I would like it recorded as the reason anyway.

Then Councillor Sorrentino-Mbeki brought her motion, and it was two sentences long, and it took the chamber four hours to understand it and eleven minutes to pass it.

"That this Council refers to the Bowl the question of the Instrument Trust," she read. "And that, pending that referral, all instrument records retired under the Charter be restored to the public archive in full fidelity."

It was the Registrar who explained it, because she was the only person in the room who could, and she did it standing, from the witnesses' bench, with the Charter open in front of her at a page she had clearly known by heart for sixteen years.

"Article nine," said Thea Marchetti-Owusu. "The astrometric instruments and their records are placed under the Instrument Trust, in perpetuity, for the benefit of arrival." She looked up. "Perpetuity," she said, "was the word they fought over in Y13, and it is the word every Registrar since has hidden behind, including me, for sixteen years. It means nobody can take the instruments off the Trust. It does not mean what we have all pretended it means, which is that nobody can look at them. Nothing in article nine restricts publication. Nothing in it authorises retirement of a record. The retirements were done under a Standing Order of this office — not the Charter — and a Standing Order of this office can be rescinded by this office, and I rescinded it at 0600 this morning, and the councillor's motion asks you to make that permanent so that my successor cannot un-rescind it on a bad Tuesday."

"How much is there?" somebody asked.

"I don't know," said the Registrar. "That's the honest answer and it's a disgraceful one. There is a ledger of retirements. It has four thousand one hundred and six entries between Y13 and Y79, and each entry is a date, a record reference, and the word retired. I have read the ledger. I have never opened a single one of the records, because opening one would have required me to write down why."

The vote was twenty-two to nothing, and then the Chair, who had said almost nothing for five hours, asked whether anybody wished to add anything before the referral was drafted, and Councillor Iwu-Grenfell — who had asked the question about one tired woman, and who had by then been sitting with his hands folded for four hours — said: "Chair. I'd like the referral to the Bowl to include the two coupons. Physically. On a table, with a lamp and a glass, in the middle of the floor, for the entire three days, and anybody who wants to look may look, and nobody is to be told what they are looking at until they have looked."

The referral to the Bowl was set for the first three days of the seventh month, which gave the ship nineteen days, and Sol spent eleven of them at the front of the ship taking blanks off slits.

It was, in the end, work. That was the part she had not been able to explain to anybody and had eventually stopped trying to: that after the vote in the chamber and the names read out and the two coupons going hand to hand along a curved table, what there actually was, every day, was a walkway forty metres long with eleven stations still to do, and a cold that got into your teeth, and eight captive fasteners at a time.

They did them in numerical order because Merced had insisted on it, and Merced now ran the gallery as a Structures work area with a permit board at 5-A and a sign-in sheet, and there was a kettle at the aft end near the nail, which Kemi had brought up and which Chief Ekwueme-Strand had looked at for a long moment and had then said nothing whatever about.

Kemi did the fasteners on nine of the eleven, because it was her plant and because she asked to. Ruy Ferrão came up on the fourth day and did station six without speaking to Sol at all, and then, at the end of it, standing in the lit gallery with the blank in a bag under his arm, said, to a point on the wall about a metre to the left of her:

"He'd have hated all this. Rufino. He hated a fuss."

"I never met him."

"No." Ruy looked at the empty mount and its three thumbscrews. "He taught me to pull a tether through my hands. Every metre, every time, on my knees, and he'd say — " the man stopped, and started again — "he'd say, nobody's going to check this but you."

He went aft. He came back the next day and did station seven.

The projectors came out one by one and went to Trust custody in numbered bags, and the blanks came off, and behind each of them was a slot two hundred and forty millimetres by eighteen with a chamfer as sharp as the day it was cut, and beyond that a wall of unmoving light with holes in it, and each time it happened somebody in the gallery stopped what they were doing and went and looked, and nobody ever said anything.

On the ninth day, at station three, Jaiye Vance-Oyelaran, who had come up between shifts every day for a week to read rating plates aloud for the record, put her eye to the open slot for a long time and then sat down on the grating with her back against the yellow rail.

"It's not going to work," she said.

Sol put down the driver.

"Say it properly."

"The stack." Jae had her forearms on her knees and was looking at the grating. "I've been running the numbers as they come in. Twelve honest channels, all of them looking at real sky for the first time in sixty-one years, and the eclipse epochs are beautiful, Sol, they're beautiful, the timing residuals are the cleanest thing I have ever seen come off an instrument." She rubbed her face. "And I still can't give you a position."

"Why not?"

"Because a position needs a baseline. Astrometry is parallax and parallax is motion — you measure a star from here, and then you measure it from somewhere else, and the somewhere else has to be far enough away to make an angle." She laughed, one breath. "At book speed we'd move a tenth of a light-year in a year. That's a magnificent baseline. You could do the whole galaxy off it. At a fortieth of book we move two and a half thousandths of a light-year in a year, and our angular precision is what it is, and I've run it four different ways, and the answer is that this ship has to travel for between eleven and fourteen years before its own instruments can independently establish where it is to better than the error on the Y11 dead-reckoning."

Sol sat down on the grating opposite her.

"Eleven years."

"Eleven to fourteen. I can give you the velocity to three percent inside eighteen months, because velocity's a rate and rates are kind. The absolute position — " Jae shook her head. "We know where we are because we know where we started and how fast we've been going and for how long, and every one of those is now a real measured number instead of a story, and that's enormous, and it is also exactly what the Bridge has been publishing since Y19, just with a different multiplier in it. I'm going to have to stand up in the Bowl and say that."

"Then say it."

"They'll hear she doesn't know either."

"Some of them will." Sol pulled her knees up. "Jae. What's the first honest number that comes out of twelve open slits?"

"Velocity. To three percent, in eighteen months."

"And what's the second?"

Jae looked up.

"Whether it's changing," she said slowly. "Whether we're — " she stopped. "Interstellar drag. The medium. We've been ploughing hydrogen for eighty years with three hundred tonnes of Cap and no thrust, and nobody has ever measured our deceleration because nobody was allowed to measure anything."

"How long?"

"Four years. Maybe three." Jae was already writing on her hand with a stylus, which Sol had noticed she did when the slate felt too formal. "Oh, that's — Sol, that's actionable, that's not philosophy, that's a number that tells you whether the four-hundred-year hull has to be a six-hundred-year hull or a nine-hundred-year hull, that's an input to the Survey — "

"Then that's your nine words," said Sol. "Not I don't know where we are. In three years I will know whether we are slowing down."

Jae sat with her back against the rail of a walkway at the front of a ship going nowhere and looked at the stylus marks on her own hand.

"My grandfather got a berth with a window bay," she said.

"Yes."

"I keep waiting to be offered something." She said it lightly and it did not come out lightly. "Genuinely. Every time somebody senior speaks to me kindly I go cold. And nobody's offered me anything, and I think it's because there's nothing left to offer, and I don't know whether that means we won or whether it means the offering was never a person's decision in the first place."

"Both," said Sol. "That's usually how it comes."

She went to the Grove on the last night before the referral, which she had not done since the committal.

It was two decks of soil and low light at Frame 15, and the trees in it were small and hard and eighty years old, and under each one was somebody. Bett Osei was in the eleventh row, under a persimmon that would not fruit for another four years, with a plate the size of a hand: OSEI, BETHANY IFEOMA. Y-6 – Y80. HULL STRUCTURES. SHE BUILT IT HEAVY WHERE SHE COULD.

Merced had written that. The guild had refused to let anybody else write it and the guild had been right.

Sol sat down on the edging with her back against the persimmon and did not say anything for a while, because Bett would have found being talked to intolerable.

Nadia Okonkwo-Reyes was eleven rows further on, under a fig; Sol had found her the week before. The plate said PROPELLANT ARCHIVES and gave two dates and nothing else. Councillor Sorrentino-Mbeki had put in a request, through the proper channel, in writing, for the addition of a single line, and the request was in a queue somewhere behind four hundred and eleven thousand others, and the councillor had said, in the corridor, with enormous satisfaction: good. Let it queue. Let it queue in public.

Ansel Ferreira-Sunquist was not in the Grove. Sol had looked. He was in the Grove in the record — remains committed — and he was not in the Grove in fact, because there had been no remains, because a man's regulator had iced at a rosette in Y69 and he had been brought in and there had been a service and the record had said what the record said. There was a tree in row four with his name on it, planted over nothing, which somebody had done in Y69 because the alternative was to write down what had actually happened.

She had asked the Registrar whether that could be corrected too, and Thea Marchetti-Owusu had said: yes. It'll take two years and it will involve seven offices and a Charter question about the definition of committal, and I have already started, and I would like you to know that starting it was the first thing I did after I signed the determination, before I went home to my wife, at two in the afternoon on the eleventh of the fifth month.

Sol sat under the persimmon until the Grove lights went to their night level.

Then she got up and went to Frame 26, because it was the tenth of the seventh month and she had promised.

Tico had the model on the fold-table and he had rebuilt it twice since the seventeenth of the fifth, and it was, at eight years old — he had turned eight in the sixth month, and the party had been thinly attended and nobody had said why — a genuinely good piece of work.

The gallery inside the paper hull was the right length now. He had measured it off a tracing of sheet nine that Chief Adaeze Ekwueme-Strand had made herself, in pencil, on tissue, in response to a letter written in ink with a date on it, and had sent down with a note that said Dear Mr Ibarra-Nakashima, thank you for your enquiry. The gallery is 41.2m along the centreline of the walkway. I enclose a tracing. Please return it when you no longer need it, or keep it if you take up the trade. A. Ekwueme-Strand, Chief, Forward Structures.

He had kept it. It was pinned above his bunk where the string model used to hang.

"The lights are wrong," he said, before she was through the door. "I put them on the ceiling. Merced says they're on the wall, on bosses, because you can't get a ladder in there."

"Merced's right."

"So it's wrong."

"So make the next one right," said Sol.

He gave her a look of such profound eight-year-old exasperation that she had to turn away and put her bag down.

Camila came out of the other room with her sleeves rolled and flour to the elbow, which was a thing she did when she could not sleep, and there was bread rising under a cloth and it was 2140 at night.

"He's got a question," she said. "He's had it for four days and he's been saving it for you, and I've told him he can ask it, and I want you to know that I've spent four days deciding that."

Sol sat down at the fold-table.

"Ask."

Tico put both hands on the paper ship, on the spin ring, one on each side, the way you hold something to keep it from being taken.

"Do we get there?"

The kitchen was very warm and smelled of yeast, and somewhere on the terrace below a door opened and a burst of music got out and was shut in again.

Sol did not look at her sister. She had learned that much, at least: that looking at Camila now would make it a conversation between adults over a child's head, and that this was the single most damaging thing she could do in this room.

"No," she said. "Not us. Not you, and not your children, and not their children. Nobody who is alive now is going to arrive anywhere, and the place we were going to, we're not going to at all, ever. That's the true thing and I'm not going to say it a nicer way, because you'd know."

Tico's hands stayed on the ship.

"Then what's the point," he said. It did not come out as a wail. It came out flat and hard and slightly angry, which Sol thought, in some distant part of herself, was the best possible sign.

"That's the right question and I'm going to answer it in two parts and the first part is bad," she said. "The first part is: for about four hundred years, nobody knows. The hull was built to last four hundred years because it only had to last a hundred and seventeen with margin, and the air machinery drifts somewhere after six hundred, and that's not a thing anybody can fix by being brave or by being sad. It's a thing you fix by rebuilding a ship while you're living inside it, in the dark, with what you've got, and nobody's ever done it, and it might not work."

"So we die."

"Eventually everybody dies. That was always true and it hasn't changed today." Sol put one finger on the paper Cap, grey, rubbed with pencil lead, rough. "Here's the second part. Do you know what your Aunt Bett worked out, ten days before she died, sitting in a chair, at eighty-six?"

He shook his head.

"Mass is free."

"What?"

"Every single thing on this ship was made light, because when you're going somewhere fast, every extra kilo costs you a day of arrival. Every plate, every shelf, every bracket, every centimetre of shielding, thin and light and just barely enough — for a hundred and seventeen years." Sol leaned in. "We're not going fast. We're never going fast. So it doesn't matter what it weighs. Not one gram of it matters. And there are four hundred and eleven thousand things aboard this ship that were made thin for a reason that stopped existing before your grandmother was born, and every one of them can be made thick."

Tico looked at the ship under his hands.

"Out of what?"

"Out of the ship," said Sol. "Out of the parts we were only carrying because we were going to land them. There are landing legs in the aft holds, Tico. There are four hundred tonnes of them. They're for setting down on a world that we are never going to see and they are the best steel on this vessel, and one day somebody is going to cut them up and make hull out of them, and I hope to God I live to see the work order."

The boy was quiet for a long moment.

"Will I see it?"

"You'll write it," said Sol.

His face did the thing it had done at the door in the fifth month, when he had been told the Cap was cold: the sudden downward look, the intense private processing, a child being handed something bigger than the question and deciding whether to pick it up.

"I'd need to be licensed," he said.

"Thirteen years."

"Twelve." He was already turning the model over, looking at the underside, at the aft holds, which he had never bothered to draw. "It's twelve now. I'm eight."

Camila made a sound at the counter and put her floury hands over her face for a second, and Sol did not look at her, and Tico did not notice, because he had got a straightedge out of the drawer and was measuring the aft third of his own ship.

They took the coupons down at 0600 on the first of the seventh month and put them on a plain table in the middle of the Bowl floor with a lamp and two loupes and a card that said LOOK FIRST. ASK AFTER.

Ninety-one hundred people were entitled to attend. Something over five thousand came at some point across the three days, in shifts, in ones and in families, because the ship still had to run and there were four thousand items being recertified a day now and somebody had to keep the water clean.

Sol went down at 0620 on the first morning and stood at the rail on the second terrace, and watched the queue form around a table, and did not go near it for three days.

The Bowl was two hundred metres of curved deck under a deckhead that had been lit for ninety years to look like weather, and on the first morning of the referral the Programme did the only thing Camila had asked her Director for, and Sol had not known about it in advance, and it took the legs out from under her.

At 0630, the Bell rang.

One note, low, from the speakers in the deckheads, exactly as it had at 0630 on every eleventh for ninety years and, since the twelfth of the fifth month, every single morning — because Camila's working group had put in a recommendation at the end of the first terrible week that the Bell be rung daily, at no cost, for no reason, in a ship that had lost its calendar; and the Council had passed it without debate; and nine thousand people had, without any of them deciding to, begun to stop for a second wherever they were, once a day, at half past six in the morning.

Five thousand people in the Bowl stopped.

The floor did not move. Nothing shoved. Nobody's cup rippled.

And then the queue started up again towards a plain table with two pieces of metal on it, and Sol Ibarra-Nakashima stood at the rail with her hands wrapped around it and understood that her sister had won her argument in the only way that had ever been available to anybody aboard, which was by putting a true thing in a form that a person could stand in.

The three days were not dignified.

There was shouting on the first afternoon, a knot of forty people at the foot of the west stair chanting WHO KNEW, and a scuffle at the table on the second morning when a man of sixty tried to take the manufactured coupon and put it in his pocket, and was stopped, and wept, and turned out to be a retired stores clerk from Frame 6 who had spent nineteen years signing consumables into a machine shop he had never been inside, and who was interviewed at length by two councillors that evening and had, it emerged, nothing to tell them at all.

There was a woman on the second day who stood at the speaking place for her allotted four minutes and used all of them to read out the names of her four grandparents and their grades and the years they had died believing, and did not draw a conclusion, and stepped down.

There was a boy of about sixteen who asked, into a silence of five thousand people, whether the ship could turn around and go back to Earth, and Jaiye Vance-Oyelaran, who had been called to answer technical questions and had been on her feet for six hours, said: "No. I'm sorry. It's not a matter of whether we would want to; there is nothing to turn with and there never will be. I'd rather tell you that in one sentence than make you find out slowly." And the boy said, "Okay," and sat down, and about a hundred people around him put their hands on him.

And on the third day, at 1420, a woman from Hydroponics whose name Sol never learned took her four minutes and said:

"I've looked at both of them and I can see the difference and I believe every word. I just want to say — and I don't want an answer, I want it said out loud in this Bowl once — that somebody made that fake one. Twice a year. For sixty years. And somebody carried it up and put it in a rack and lined the notch up. And it wasn't a monster, was it. It was a technician on a shift." She looked around at the terraces. "I've been in Hydroponics thirty-one years. There's four hundred things I do every week because the schedule says so. So that's all. That's what I wanted said. It's us. It was always going to be us."

Nobody applauded. Somebody would have, in Y79, at a Milestone. In Y80 five thousand people made a sound that was not applause and was not silence, and the Chair let it run for eleven seconds before she called the next speaker.

The vote was held on the evening of the third day and the question was not the one that anybody had expected in the fifth month.

There had been talk, in the first weeks, of a vote on the Consensus itself — of some grand ratification or condemnation of the four-to-one in Y11, the whole ninety years of it, up or down. Camila had killed that in a working group in the sixth month with one sentence, which she reported to Sol afterwards with a kind of horrified pride: We are not going to hold a referendum on our great-grandparents, because they will lose, and then we will have to be the kind of people who did that.

So the question on the boards on the third evening was four lines long and had been drafted by Councillor Sorrentino-Mbeki and rewritten eleven times by a subcommittee, and it read:

*That the Anabasis is not able to reach Hale, and that its complement shall not be told otherwise.

That every record retired under the Charter be restored in full fidelity to the public archive, in perpetuity, and that no office of this vessel shall hold authority to retire a record again.

That the Survey of design life be established as a standing activity of every grade, and that the certified design life of this vessel be set, until further finding, at not less than one thousand years.

That the eleventh of the fifth month be kept as it has been kept, without expenditure.

It carried on all four limbs. The first limb, which was the one everybody remembered, carried by six thousand eight hundred and eleven to nine hundred and four, with four hundred and eleven abstentions recorded and, at the Chair's insistence, published as a separate figure, because Sorrentino-Mbeki had argued in committee that an abstention on a question like that was a position and deserved a number.

The third limb, the thousand years, was the one that took four hours of argument and passed most narrowly, and the argument was not about whether it was possible. It was about the word until. A young structural analyst from Frame 17 stood up and said that a thousand years was not a design life, it was an aspiration, and that certifying to an aspiration was exactly what had been done to them for ninety years, and that if they did it again they would deserve everything they got. And Chief Adaeze Ekwueme-Strand, seventy-one years old, took the speaking place for the first and only time in the whole three days and said:

"He's right. It's not a design life. It's a target, and I'd like the record to show that the chief of Forward Structures says so and would refuse to sign a certificate to it today. But I'll tell you what a target is good for." She put her scarred hand on the rail. "For eighty years, every one of my people has done the arithmetic on a hundred and seventeen years and stopped. Every calculation on this ship stops at Y197 because that's where the world ended. I want a number that doesn't stop, because I want to find out which of my four hundred thousand items falls over first, and I can't find that out until somebody makes me calculate past the wall. Give me a thousand years and I will bring you back a list of everything on this vessel that fails before then, and it will be the longest and most useful document ever written aboard, and then* you can argue about what's achievable."

They gave her the thousand years by two hundred and eleven votes.

At 0212 on the fourth of the seventh month, third shift, in the Quiet, with the lumens at eleven percent and the amber runners along the deck seams like the last coals of something, Marisol Ibarra-Nakashima was on her back in the crawl behind Frame 40 with her elbow in the guts of Photometric Channel Fourteen.

The channel had been out of solution for eighty-four days. It had had its cryo-shunt replaced in the fourth month, its blank removed in the fifth, its first surface characterised in the sixth, and its aperture edge measured, photographed at twelve magnifications, and found to be within nought point nought one millimetres of the chamfer Folasade Ekwueme had specified in a shed on Phobos before there was a ship. The Ekwueme curve had been recomputed at measured flux and now predicted the first aperture reconditioning for approximately Year 3,240.

Sol had put that number in the file with a straight face and had then gone and sat in a service corridor for eleven minutes.

Tonight she was refitting the cold chain, because the portable head had to come off and the permanent head had to go back on, and because a channel with a suspended certificate is still a channel and somebody has to keep the vacuum up.

"Fourteen, this is fourteen," she said into her collar. "Cold chain's back on. Bringing it down."

"Copy fourteen." Pim, chewing something. "You want the stack held?"

"Nothing to hold. It's still out of solution."

"It's still out of solution," Pim agreed, with feeling. "Sol. You know the log's up to eleven thousand lines of channel fourteen rejected."

"I know."

"Nav sent a note down. That astrometrist. She says when you close the certification, she's going to print the whole log out on flimsy and hang it up her stairwell."

"That sounds like her."

The shunt took the cold beautifully. Sol watched the temperature curve fall away like a dropped rope, seventy kelvin, sixty, the noise floor dropping with it into that clean, black, ridiculous quiet where a machine could hear individual particles of light arriving from fourteen light-years away.

And then the counts began, and Channel Fourteen sang to her.

She put her palm on her thigh out of nineteen years of habit and let it lie there, still, and listened.

The eclipse was in a phase she had never heard before, because she had never in her life heard a phase that had not been drawn out of a bag. On top of it the flares came the way they came: a spike at four minutes with a fast rise and a slow tail, nothing for six, a doublet close together that her hand did not anticipate, a long dead patch. Somewhere fourteen light-years away a young furious little red dwarf was snapping magnetic knots in a plasma no one would ever visit, keeping no time for anybody, and doing it, tonight, in Sol's ear, live, at the speed of light, for the first time in sixty-one years.

She lay in the dark under Frame 40 with her tools on her chest and did not try to drum it, and did not try to name it, and let it be exactly as unpredictable as it was.

At 0240 she came out of the crawl and sat with her back against the frame and pulled her slate over and opened WO-14C-0502-1, which was still open, because she had recommended that it remain open and the Registrar had countersigned the recommendation and a Council had voted a design life of a thousand years around it.

There was a new field at the bottom of the form. It had appeared in the fifth revision of the work-order template, three weeks ago, along with eleven other changes that had come out of the Survey, and it was the only one anybody talked about, and nobody knew who had asked for it, and Sol had a suspicion involving a keyworker at Frame 19 who had never once summarised her.

The field was headed: FOR THE BENEFIT OF ARRIVAL — NOTES TO A FUTURE GRADE.

She looked at it for a long time, and at the amber runners going away down the Rib, and at the dimmed corridor of a town two kilometres long inside a machine that was not going anywhere and would have to become something else, slowly, over four hundred years, by hand, in files, at a rate she could calculate.

Then she wrote:

Channel 14 is looking at real sky. It has been since 0705 on 11/5/80. Whoever you are: put the buds in and listen to it on a cold night, because it is the only thing aboard this ship that no one has arranged, and I would like you to have heard it.

Do not trust this record. Trust it more than you trusted the last one, and less than you'll want to. Every liar aboard here was a good technician doing a scheduled task.

Count the pits. Count the fuel. Count the years past the year you were told to stop counting at.

And when you find something, do not go to a friend and ask to be believed. Put your hands on the metal, then put it on a form.

She read it back. It was too long by about forty words and she did not cut it.

She thumbed it, and filed it, and stood up, and her knees complained, and she went forward into the Quiet to see about the eleven other channels, because it was third shift and there was nobody else on it.

The restoration got a room at Frame 34 that had been a committee room, and a trestle, and eleven crates a week up from Deep Stores on a trolley pushed by whoever was on the roster, and no budget at all, because the Council's second limb had said restored to the public archive in full fidelity and had said nothing whatever about how.

Sol had asked for it. That was the part her sister could not get over.

"They offered you the Trust seat," Camila said, in the seventh month, standing in the doorway of the empty committee room with a folder under her arm. "Grade Five. The safe. The chair when Marchetti-Owusu goes. And you asked for a filing job."

"I asked for a filing job with a title, so that nobody could take it off me on a bad Tuesday," said Sol. "Custodian of Restoration. It's unpaid, it's third shift, and it comes with a stores code."

"That's not an answer."

"It's the only answer there is." Sol put a crate down on the trestle. "Cami, there are four thousand one hundred and six entries in that ledger. If I sit in the chair at Frame 22 I will spend nine years signing determinations and eleven people will do this badly. If I do this, somebody else signs the determinations, and they'll be all right, and in nine years there will be four thousand one hundred and six records back on the public board where a schoolteacher can find them."

So it was a filing job, and it was tedious beyond description, and it was, in the way of such things, oversubscribed within a month.

They came in on their own time. That was the thing nobody in Programme had modelled and that Camila's working group eventually wrote a paper about: that in the ninth and tenth months of Y80, with the Mood Index at four point one and the P-7 caseload at eighty-one and the Council in permanent session, what a substantial number of people wanted, in the evening, after shift, was to sit in a room at Frame 34 with a crate and a ledger and put things back where they belonged.

Ify Aduba brought her class of eight-year-olds on Thursdays and had them read reference numbers aloud while an adult found the box, which was, she said, the best number practice she had ever devised and also the only civics lesson she had ever taught that the children took home and repeated at dinner.

Merced Ekwueme-Strand came twice a week and did the heavy crates and said almost nothing.

Yusuf Baptiste-Lindgren came on Tuesdays and worked through his caseload's worth of exhaustion in silence for two hours, and once, when Sol asked him why, said: "Because eleven percent of my referrals this year are people who cannot stop reading the board, and I would like to be able to tell them, truthfully, that I have read it too."

And in the eleventh month, a man of sixty-one with a limp and a stores clerk's handwriting presented himself at the door of the committee room at 2140 on a third shift and said, without preamble:

"You'll not want me."

"Why not?"

"Osvaldo Prieto-Mensah. I'm the one from the Bowl. The table. The coupon." He had his hands behind his back like a man at an inspection. "I tried to take it. I don't know why. I've been asked by two councillors and a keyworker and my daughter and I have no explanation and I have stopped trying to make one, and I would like to point out that I have been asked eleven times what I knew and the answer is nothing. I signed consumables into Frame Six for nineteen years. Abrasive, iron powder, argon, filter cartridges, a monthly allocation for a machine described on the form as a calibration rig, and I never once went through the door, because it wasn't my door."

Sol looked at him for a moment.

"Can you read a ledger?"

"I can read a ledger better than anybody alive on this ship," said Osvaldo Prieto-Mensah, with a flash of something that had clearly been buried for six months under being forgiven. "I can read four kinds of ledger. I can read the yard ledgers, which nobody can, because they used a prefix system that was abandoned in Y-4 and never documented."

"Sit down," said Sol.

The ledger of retirements was a single bound volume with four thousand one hundred and six lines in it, in seventeen hands, between Y13 and Y79, and the lines had three fields: a date, a record reference, and the word retired.

That was all. There was no reason column. There had never been a reason column, and it took Sol four months to understand that this was not an omission but the entire mechanism — that a form without a reason field is a form that cannot be argued with, and that seventeen Registrars had written four thousand one hundred and six lines in it without once being required to complete a sentence.

Prieto-Mensah sorted the references by prefix in nine days.

He did it because nobody had asked him to and because it was obviously the first thing anybody should have done, and he presented the result to Sol on a Thursday in the first month of Y81 on four sheets of flimsy, in a clerk's block capitals, with the counts in a column on the right.

OPT/ — photometric channel records — 2,911
ACW/ — acoustic witness, Bow Cap — 806
STR/ — structures, coupon and plate — 191
MED/ — care archive, closed cases — 61
MISC/ — 76
RX/DS — 60

"That last one," he said.

Sol looked at it.

"RX," said Prieto-Mensah, "is a receipt. It's a receipt prefix. It's in the yard system: RX slash something is a thing that came in. RX slash M is materials, RX slash V is vendor documentation, that's all pre-Departure, it dies in Y-1." He put his finger on the line. "DS isn't in the yard book. I've looked in four places. But whatever it is, sixty of them came in, and somebody retired all sixty, and they're spread from Y41 to Y79, which is the only prefix in this ledger that doesn't cluster."

"They're all spread," said Sol. "That's the shuffle. That's the bag."

"No." The clerk's finger did not move. "The others are spread because a Registrar retired them in batches whenever a batch came up. Look at the dates on the OPT block. They go in tens and twelves, three or four times a year, for sixty years — that's a woman doing a chore." He turned the sheet. "The RX ones are singles. Sixty entries, sixty separate dates, no two in the same month, one or two a year for thirty-eight years. That's not a chore. That's somebody making a decision, sixty times, one at a time."

Sol sat down slowly on the trestle.

"Where are the boxes?"

"That's the thing," said Osvaldo Prieto-Mensah. "There aren't any. Deep Stores has no holding for that prefix. There's no crate, there's no shelf, there's no transfer note. Whatever RX slash DS is, it never went to Stores, which means it never left wherever it was made, which means it's still there, and I don't know where there is, because I only ever signed for things going into a room."

It was aft, of course. Everything nobody thought about was aft.

Comms & Telemetry lived at Frame 61 in three compartments and a plant room, and their whole grade was the internal net: nine thousand people's boards and slates and lift indicators and the deckhead speakers that rang the Bell at 0630. They were twenty-two strong. They had a duty roster and a good safety record and, on the wall of their shop, a hand-painted sign that said WE ARE NOT NAVIGATION, which Sol understood within four minutes of arriving was ninety years old and had been painted by somebody who was tired.

The chief was a woman of fifty named Rosalind Achebe-Vantongeren, and she listened to Sol for six minutes without interrupting and then said:

"You want the Ear."

"I want to know what RX slash DS is."

"RX slash DS is the Ear." The chief got up. "Come on. It's four decks down and it's cold and there's nothing to see."

The compartment was two metres by three and had a rack in it, and the rack had eleven pieces of equipment in it, and ten of them were dead and one of them had a status lamp on.

"Deep Space Receive," said Achebe-Vantongeren. "One antenna, aft-facing, sixteen metres, deployed in Y2 and never stowed. One front end. One recorder. It runs continuously and it has run continuously since Y2 and it is, as far as I know, the oldest continuously operating instrument aboard this vessel, and my grade has maintained it four times a year for eighty-one years." She put her hand flat on the rack in a way Sol recognised, and hated recognising. "And I have never in my life been told what it is for."

"You've never asked?"

"I asked in Y58, when I was twenty-seven. My chief said it was the noise-floor reference — that it listens to the sky in a band nobody uses so that we can subtract the sky from the internal net." The chief's mouth was flat. "That is a completely plausible sentence. It is technically coherent. I have repeated it to four apprentices."

"Is it true?"

"It's true that we've never used it for that," said Achebe-Vantongeren. "We haven't needed to since the Y31 rebuild. We keep it because it's on the schedule." She looked at the one lit lamp. "The recorder writes to a buffer and the buffer goes to the Trust, quarterly, on a physical cartridge, and my duty tech carries it up to Frame Twenty-Two and hands it over and gets a chit. It's four hundred metres and it takes eleven minutes and we've done it three hundred and twenty-four times."

"And the chit says?"

"The chit says received." The chief turned round. "Ms. Ibarra-Nakashima, before you say the next thing: I have been standing here since you said RX working out what I think, and what I think is that I would rather you said it fast."

"Sixty of those cartridges were retired," said Sol. "One or two a year, from Y41 to Y79, individually, on sixty separate days, by seven different Registrars. Every other quarter for thirty-eight years went into the archive as noise and nobody looked at it. Sixty didn't."

Rosalind Achebe-Vantongeren stood in a compartment two metres by three with her hand on a rack.

"They were listening," she said.

"Somebody was."

"No." The chief's voice had gone strange. "No, that's not — you don't understand what that means, and it isn't your grade, so let me say it properly." She turned the rack's log page round on its clip. "The Ear doesn't listen. It records. There's no operator, there's no analysis, there's nobody in the loop. If sixty cartridges out of three hundred and twenty-four got individually pulled out of the archive stream on sixty separate days, then somebody up at Twenty-Two was reading them, every quarter, for thirty-eight years, on the quiet, with no post and no grade and no line in any ledger — and on sixty occasions they read something and got up and walked to a different cabinet."

The recovery took eleven weeks, because the cartridges were where Prieto-Mensah had said they would be, which was nowhere, and because it turned out that six Registrars in succession had put them in the safe at Frame 22 behind the four-hundred-page Y19 plan, and because Thea Marchetti-Owusu, when Sol came and stood in her doorway and told her the prefix, went the colour of the deck plate and said, "Oh, God. The green tins."

"You knew."

"I knew there were sixty tins in my safe with no reference on them and a note from my predecessor that said hold." The Registrar had both hands on the table. "In sixteen years I opened the safe perhaps two hundred times. They were behind the plan. I moved them to get at things. I once dusted them." She looked up. "I never asked what they were, because there was a note that said hold, and because I had four thousand other things, and because — " she stopped, and made herself finish it, which Sol had learned was the one thing that could be relied on about her — "because a woman who has decided not to ask one question gets very good at not asking others."

The tins came out of the safe on the fourteenth of the second month of Y81 and went to Comms, because Comms had the only reader aboard that could still spin them, and Rosalind Achebe-Vantongeren spent nine days rebuilding the reader before she would put a single one in it, because, she said, she was not going to be the person who wrecked the first one.

They opened the earliest on the twenty-third, at 0300, third shift, with the Registrar present, and a Council observer, and Jaiye Vance-Oyelaran, and the chief of Comms, and Osvaldo Prieto-Mensah, who had been invited by Sol over the objections of nobody at all.

RX/DS/Y41-2. RETIRED Y41/06/11. I. NAKAGAWA-BELL, REGISTRAR.

It was a voice.

That was the first thing, and none of them had prepared for it, because they had all been thinking about it as a record: a signal, a data product, something to be analysed. What came out of the reader in a compartment at Frame 61 at eleven minutes past three in the morning was a woman speaking, slowly and clearly, in an accent none of them had ever heard, with the flattened vowels of a ship none of them would ever see.

"This is the vessel Cerro Rico, transmitting on the departure bearing, sequence four, year thirty-three of our voyage. This transmission is unaddressed. Anyone receiving may use anything in it. Nothing in it is proprietary and nothing in it is classified and we have no procedure for either."

A pause. Two seconds of hiss.

"I am Aurelia Mansour-Tekle, and I have the watch, and I am going to read the standing preamble because the committee makes me and because it is right that it should be read every time by whoever is holding the microphone."

"In the ninth year of our voyage a manufacturing defect in our number one boost tankage was identified. Its consequence was that the Cerro Rico completed its boost at eleven point four percent of the intended terminal velocity and cannot correct. Our arrival at the designated system, if it occurs, occurs in approximately one thousand and forty years. This information was withheld from our complement for two years while it was verified and while a proposal was prepared to withhold it permanently. That proposal was defeated in our eleventh year by a vote of the whole ship's company over four months. The truth was published on the ninth of the fourth month of our Year Eleven."

"In the twelve months following publication we lost eleven point two percent of our complement. Four hundred and nine people. I am going to read their names at the end of this transmission as we read them at the end of every transmission, because it is the only thing we can do for them and because whoever is receiving this should know the price of what I am about to tell you, and should be able to weigh it themselves rather than being told what it weighed."

Somebody in the compartment made a sound. Sol did not look round to see who.

"We are, at the time of this transmission, in our thirty-third year, and there are four thousand nine hundred and six of us, and we are not dying. Our complement has been stable for eleven years and has grown for the last four. We do not call this a voyage any more. We have not used that word officially since our Year Nineteen. We call it the Long Build."

"The remainder of this transmission is technical. It runs to approximately four hours. It contains: our closed-ecology nitrogen findings to date, including two failures we did not anticipate and which we believe are generic to hulls of our class; our current programme for internal restructure, including the recovery and reuse of landing and descent assemblies; our design-life recertification methodology, which we began in our Year Fourteen and which is now in its second complete pass; and our mortality, morbidity and social cohesion data, unредacted, including the bad years, which are the ones you will want."

"We send on this bearing twice a year. We have no expectation of reply and no capacity to receive one usefully at this range within the lifetime of anyone now speaking. We send because somebody should have the working."

The hiss went on for four seconds.

"If there is anyone out there in the same condition as ourselves: you can do this. It is very bad for about two years. It is extremely difficult for about twenty. It is then simply your life, and it is a life, and there is work in it, and our children are not unhappy. That is the whole of the encouragement I am able to offer and I am aware that it is thin."

"Names for the year, in the order of the roll."

And Aurelia Mansour-Tekle, thirty-three years into a voyage of a thousand and forty, read four hundred and nine names.

It took nineteen minutes. Nobody in the compartment moved. Prieto-Mensah sat with his hands on his knees and his eyes shut. Halfway through, Jae got up and went out and could be heard being sick in the passage, and came back, and sat down, and put her hand flat on the rack.

At the end the woman said:

"We are still here. Cerro Rico, out."

The tin had one other thing in it.

It was not part of the transmission. It had been put in the tin afterwards, in a sleeve, by hand: a single sheet of flimsy, folded once, in a small tight script, and at the top of it a reference and a date and, below, the only reason field in the entire ledger of retirements.

RX/DS/Y41-2. RETIRED THIS DAY BY MY HAND ALONE.

I have listened to this four times. It is genuine. The bearing, the drift and the doppler are consistent with the Cerro Rico's departure solution and with thirty-three years of her own flight, and no other explanation is available to me.

I am going to write down why I am retiring it, because there is no field on the form for it and because I will not be able to live with having done this silently.

It cannot be published without publishing everything. There is no version of this record that can be released which does not carry, in its first ninety seconds, the sentence "our arrival occurs in approximately one thousand and forty years," and the second question any person aboard this vessel will ask on hearing it is what our own figure is. I have consulted no one. There is no one to consult; the Consensus has no council and no quorum, it has only a chair and I am sitting in it.

I record for whoever opens this that the technical content of this transmission is of extraordinary value and that we require almost all of it, and that I am withholding it from the people who require it. I have made a working copy of the nitrogen and recertification sections and placed it in this safe. I intend to find a way to introduce the findings under other cover, gradually, as ordinary engineering. I do not yet know how. I expect it will take some years.

If I have not succeeded by the time you read this, then the honest description of what I have done today is that I heard four thousand nine hundred people tell us how to survive and I put it in a cupboard.

I am forty-four years old and I have held this office for eleven months.

I. NAKAGAWA-BELL, REGISTRAR OF INSTRUMENTS, Y41.

The Registrar of Instruments, Y64 to present, read it standing, and put it down, and said, in a voice nobody in that compartment had heard from her:

"There is no working copy in the safe."

Ilse Nakagawa-Bell held the office for nineteen years, until Y60, and there were eleven RX tins retired in her hand, and each one had a sheet in it, and the sheets got shorter.

By Y47 they were four lines. By Y52 they were one: As before. I have not found the cover. I.N-B.

The last one in her hand was Y59 and it said: I am sixty-two. I have not found the cover and I no longer believe there is one. I have introduced nothing. My successor should be told; I intend to tell him; if this sheet exists then I did not.

There were forty-nine more tins after that, in six hands, and not one of them had a sheet in it at all. Sol went through all forty-nine in nine days, in the compartment at Frame 61, with the chief of Comms sitting in because Achebe-Vantongeren had declared, on the first morning, that no cartridge was going into that reader without a Comms hand on the door, and had then simply stayed for the whole of it, four hours at a time, on her own time, in a chair she brought down herself.

They were all the Cerro Rico. Twice a year, on the departure bearing, sequence after sequence, for thirty-eight years, and the sixteen missing tins turned out — Prieto-Mensah found it in the Comms maintenance log, where it had sat in plain sight since Y44 — to be the quarters in which the aft antenna had been fouled or the front end had been down for a rebuild, and each of those quarters had a work order and a signature and a note apologising for the outage to nobody in particular.

The preamble never changed. Every single transmission, for thirty-eight years, in eleven different voices, opened with the same three paragraphs: the defect, the eleven point four percent, the two years of withholding, the proposal to withhold permanently, the vote over four months, the publication on the ninth of the fourth month of their Year Eleven. And then the number. In the twelve months following publication we lost eleven point two percent of our complement. Four hundred and nine people. And then, every time, at the end, before the technical content, the reading of the names.

By their Year Fifty they were reading two rolls: the four hundred and nine, which never changed and never would, and the year's own dead, which by then ran to eleven or fifteen or twenty-two, mostly old.

The last tin was Y79.

RX/DS/Y79-2. RETIRED Y79/10/04. T. MARCHETTI-OWUSU, REGISTRAR.

The Registrar had come down for it. She sat with her hands in her lap and did not look at the reader.

It was a man's voice, older, unhurried.

"This is the vessel Cerro Rico, transmitting on the departure bearing, sequence one hundred and forty-two, year seventy-one of our voyage. This transmission is unaddressed. Anyone receiving may use anything in it."

He read the preamble. He read the four hundred and nine, and it took him nineteen minutes, and at the end of it he said, "That is the roll of Year Eleven, which we read every time," and then he read fourteen more names, and said what they had died of, which was, in eleven cases, being old.

"There are five thousand two hundred and eighteen of us. Our nitrogen cycle has been in closed balance without external input for thirty-one years and we believe now that the six-hundred-year figure in the original studies was an artefact of the test volume and that the true constraint is elsewhere; the finding is in section two and we would be glad if it were checked by anyone with a different hull.

"Our second recertification pass is complete. Ninety-one percent of our original items now carry a design life of not less than one thousand years. The remaining nine percent are the ones that matter and section three is a list of them, and I am instructed by our engineering committee to say that the list is the most valuable document we possess and that we would trade the rest of this transmission for anybody else's.

"Our descent assemblies were cut up between our Year Twenty-Two and our Year Forty-One. Four hundred and eleven tonnes. They are now hull, shielding, and the frames of two agricultural decks that did not exist when I was a boy. The oldest argument aboard this vessel is whether we should have started sooner. My grandmother's position was that we should have started in Year Nine, before we were told, and that the withholding cost us thirteen years of steel, and she used to say it at the table until we all left the room.

"I am seventy-four. I was born in our Year Five and I remember the publication, and I remember my mother in the passage, and I will not describe it because it is not mine to spend. I will say only that I have had a life, and that the life had work in it, and that I would rather have had this one than the one I was promised.

"We are still here. Cerro Rico, out."

The reader clicked and ran on into hiss.

Nobody said anything for a while. Then Thea Marchetti-Owusu said, to the deck:

"Sixteen months ago. I signed that on the fourth of the tenth month of Y79 and I did not listen to it. I had never listened to one. I did not know there was a voice on them."

"Then why did you retire it?"

"Because the note said hold, and because there was a line in the ledger above mine in six other hands," said the Registrar. "That is the entire reason. That is the whole of it. I want it minuted in exactly those words and I want my name on it."

Camila found the citation eleven days later, and came to Frame 34 at 0130 to say so, and did not sit down.

"The appendix," she said. "The Cerro numbers. Eleven point two percent, four hundred and nine dead in the first year after publication. It's in the doctrine appendix, page thirty-one, it's the load-bearing figure of my entire profession, every Grade Two for sixty years has been taught it, Osegueda-Ferrer read it into the Council record in the seventh month — " She had a sheet of flimsy in her hand and she was holding it away from her body. "There's a citation. There has always been a citation. Nobody has ever chased it because it's a citation."

She turned it round.

Source: Cerro Rico, corr. Y41.

"Correspondence," said Camila. "Y41. That's the word in the appendix, and everyone has always read it as a document that came in with the departure archive, because how else would we have anything from the Cerro, and the answer is that we didn't have anything, we had seventy-six transmissions, and Ilse Nakagawa-Bell took precisely one number out of the first one she ever heard and put it in the Programme's doctrine as a warning."

She sat down on the trestle after all.

"She found the cover," she said. "That's what's — Sol, she found it. She wrote in Y52 that she hadn't found the cover, and she'd already used it, in Y41, in her first year, and she must have known she'd used it, and she went on writing I have not found the cover for eighteen years, and I think it's because she knew the difference between introducing the working and introducing the warning." Camila put both hands flat on the trestle. "Ninety years. The only thing that ever got through from a ship of five thousand people telling us how to survive was the price of telling."

"And they survived it," said Sol.

"They survived it and said so in the same recording." Her sister laughed, and it was a bad sound, and she stopped it herself. "Every year, twice a year, for thirty-eight years, in the first two minutes, before the names: we are not dying, our complement has been stable for eleven years and has grown for the last four. And Halim read the four hundred and nine into the Council record in good faith, and I sat four seats away and let him, and neither of us had any idea we were quoting them."

The Council published it whole.

That was not a foregone thing, and it took nine days and a hard sitting and a genuinely difficult argument, because the Cerro Rico's sections two through five ran to eleven hundred hours of technical material and the first ninety seconds of every single transmission contained the words four hundred and nine, and there was a proposal — reasonable, made by decent people, defensible in a room — to release the technical content immediately and the preambles in the spring.

Camila spoke against it. She was, by then, on the Continuity board and had been offered the deputy directorship twice and had refused it twice on the grounds that she intended to stay at Grade Two until the Survey's first pass was done, which nobody understood and which Sol understood perfectly.

"You cannot cut the preamble," she said, "because the preamble is a technical document. It is the most useful thing on the tin. Eleven point two percent in the first year, and then stability by their Year Twenty-Two, and growth by their Year Twenty-Nine, and a man of seventy-four saying I would rather have had this one. That is the mortality curve for what this ship did in the fifth month of last year, measured on a different vessel by people who did it first and wrote it down for us in case we needed it, and we have been standing on the first point of that curve for ninety years and pretending there was nothing after it."

The vote was twenty to two.

They played the Y41 tin in the Bowl on the ninth of the fourth month of Year 81, at 0630, after the Bell, because Councillor Sorrentino-Mbeki had pointed out in committee that the ninth of the fourth was the Cerro's own date — the day of their publication, seventy years earlier, in their Year Eleven — and that if the Anabasis was going to start keeping other people's anniversaries it might as well begin with the only other people there were.

Sol stood at the rail of the second terrace with her nephew beside her, nine years old, taller by four centimetres than he had been in the seventh month, holding the rail with both hands the way she had taught him to hold a handrail in thin gravity, which had no application whatsoever in the Bowl.

Six thousand people. There was no room to move on the terraces and they had opened the west stair and the concourse below and the sound was piped to every deckhead on the ship, and at 0630 the Bell rang, one note, low, and nine thousand people stopped for a second wherever they were, and the floor did not move.

And then a woman who had been dead for perhaps thirty years, on a ship nobody aboard would ever see, said:

"This is the vessel Cerro Rico, transmitting on the departure bearing, sequence four, year thirty-three of our voyage. This transmission is unaddressed. Anyone receiving may use anything in it."

Sol watched the Bowl.

She had thought, in the days before, that she knew what she would be watching for, and she had been wrong, as she had been wrong about almost everything except the metal. She had expected grief, and there was grief. She had expected anger, and there was some — a knot of people near the west stair who began, at the words withheld from our complement for two years, a low sound that went on for about eleven seconds and then, when the recording reached that proposal was defeated in our eleventh year by a vote of the whole ship's company, simply stopped.

What she had not expected was the noise at four thousand nine hundred and six of us, and we are not dying.

It was not a cheer. Six thousand people in a Bowl did something with their breath, all at once, and it made a sound like a room in a hull going to a different pressure, and Sol felt it in her chest, and beside her Tico said, "What?" and she found she could not answer him.

They stood for the names.

Nobody had told them to. There was no instruction, no observance, nothing on the boards; Camila's office had put out a single line the night before, which said only the recording runs four hours and nine minutes and contains a roll of the dead near the beginning. And at names for the year, in the order of the roll, in a Bowl where five thousand of the six thousand had brought something to sit on, everybody stood up.

Nineteen minutes.

Sol looked along the terraces at some point in the eighth or ninth minute — she had lost count of the names, everybody lost count of the names, that was what they were for — and she picked out, in the crowd below, Chief Adaeze Ekwueme-Strand with thirty-one members of Forward Structures standing in a block; and Merced with a child on her shoulders; and Kemi Odeleye-Vance and Ruy Ferrão and the whole of the Trust maintenance detachment, four men and a woman, standing together at the back the way people stand who have been being sworn at for a year; and Jaiye Vance-Oyelaran on the third terrace with her Nav coverall unfastened at the throat, and beside her, in a chair somebody had carried down, Naveen Duarte-Chatterjee, sixty-nine years old, who had signed a work order in the fifth month of Y80 and had made a point ever since of looking at what he signed.

And on the floor of the Bowl, at a plain table that had held two coupons for three days in the seventh month of Y80 and had never been taken away, Osvaldo Prieto-Mensah stood with a ledger under his arm because he had not been able to think what else to do with it.

At the end the man's — the woman's — voice said:

"We are still here. Cerro Rico, out."

And six thousand people stood in the Highland wash of a deckhead lit for ninety years to look like weather, and did not know what to do, because there was no observance for this and nobody had written one and the Programme had, for the first time in its existence, declined to.

So Camila had put one thing on the schedule, and one thing only, and she had cleared it with nobody and had told Sol about it at 0400 that morning in a corridor.

At 0658 the Bell rang again.

Once. Low. Out of turn, out of the calendar, twenty-eight minutes after it had already rung, for no reason at all except that it was the only thing this ship had that meant we heard you, and it cost nothing, and it would never again be followed by four hundred and six kilograms going out of a nozzle.

The transmit chain was dead, and it had been dead a long time, and finding out how dead took Comms four months.

Sol had asked the question in the compartment at Frame 61 on the ninth day of listening, in the middle of the Y58 tin, and had asked it so quietly that Achebe-Vantongeren had made her say it twice.

"Can we answer?"

The chief of Comms had put down her tea.

"There's a transmitter," she said. "There's the Earth-link. Sixteen-metre dish, forward-facing, deployed in Y2, same programme as the Ear. We ran traffic on it until Y31 and then Earth stopped answering, or we stopped being able to hear the answer — the record's ambiguous, and I have always assumed the ambiguity is us and not them. It's been passive since. My grade inspects the feed horn every second year and the log says serviceable, and I would not bet a shift's pay on that word."

"Why not?"

"Because serviceable means the man before me wrote serviceable," said Achebe-Vantongeren, "and because it has not radiated in fifty years, and because I have never in my life been given a reason to find out, and because there is a sign on my wall that says WE ARE NOT NAVIGATION and I have finally understood, in the last nine days, that somebody painted it as a complaint."

So Sol filed a work order.

It was four pages long and it went in on the eleventh of the fifth month of Year 81, and it was, in shape and in method and very nearly in wording, the same document she had filed a year earlier about a chamfer: fault, analysis, two explanations, falsification attempts, margin.

WORK ORDER WO-CR-0511-1. ORIGINATING GRADE: COMMS & TELEMETRY, with HULL OPTICAL & SENSING in support.

SUBJECT: Characterisation of the forward transmit chain (Earth-link, deployed Y2), from exciter to first surface.

FAULT: The transmit chain of this vessel is documented as serviceable on the authority of biennial visual inspection of the feed horn and on no other basis. It has not radiated since Y31. No end-to-end test of the chain exists in any record. The condition of the exciter, the final amplifier, the waveguide run, the rotary joint and the dish surface is therefore undocumented, or documented by a process which cannot be independently verified.

ANALYSIS: Two explanations exist. Either the chain is capable of radiating, in which case this vessel has possessed for fifty years, unexamined, the ability to answer a transmission it has been receiving twice a year for forty years; or it is not, in which case the restoration of that capability is a matter of engineering and should be scoped now, in daylight, at known cost, by people who are permitted to say what it is for.

REQUIRED ACTION: End-to-end characterisation, with metrology, photography at 12×, and one external inspection of the dish surface and feed geometry by qualified grade, tethered, two-person minimum.

MARGIN: The originator notes that she is not a Comms grade, that the fault was identified by Chief R. Achebe-Vantongeren, and that the chief has asked to be named as originator and has been refused on the grounds that she has to hold the shop.

PURPOSE (entered under protest of the originator, who was advised that this field is not required and has elected to complete it): So that the working can be sent on.

It was countersigned in nine days, which was seven days faster than anything had ever been countersigned aboard the Anabasis, and the reason it was countersigned in nine days was that the Council had, in the third month, and largely because of an argument made by a very old woman from Ribs Two, adopted a standing rule that no work order bearing the words end-to-end could be held longer than a fortnight without a written reason.

Sol went out for the dish inspection in the ninth month of Y81, on a full ticket, at forty-two years old, with Kemi Odeleye-Vance tending her line and Teo on the rail two metres behind her at all times, and it took ninety-four minutes, and her hands went at eighty-one, and she said no out loud into the loop at eighty-three when she wanted to go four metres further than the plan and, and there was a recording of her refusing.

The dish was intact. The feed horn was fine. The rotary joint had seized solid in about Y44 and would need to be cut out and remade, and the final amplifier was a total loss, and Comms put the restoration at four to six years with the fabrication capability that Forward Structures had been keeping alive under Chief Adaeze Ekwueme-Strand since Y66 for reasons the chief had spent forty years believing were her own idea.

Sol got that estimate on flimsy on a Tuesday and read it in the alcove at Frame 33 with a bun she had actually eaten, and the board above her said, in type the same height as the figure it qualified,

VELOCITY, MEASURED: 748 KM/S ± 2.1%
POSITION: PROVISIONAL — SEE INSTRUMENT NOTE 81/206
DESIGN LIFE, CERTIFIED: NOT LESS THAN 1,000 YEARS — SURVEY PASS ONE: 39% COMPLETE
DAYS SINCE PUBLICATION: 496

and underneath, small, because the Programme had lost the argument about making it large and had, in Camila's view, deserved to:

The Bell rings at 0630. Nothing burns.

Four to six years. She would be forty-six, or forty-eight. Jae would be thirty-two. Tico would be thirteen or fifteen, and licensed at twenty, and it occurred to Sol, sitting there with the flimsy on her knee, that the first Anabasis transmission would very probably go out on the departure bearing while her nephew was an apprentice, and that somebody would have to hold the microphone and read a preamble, and that the preamble would have to say what had been done and how long it had been done for and by whom, and that four hundred and eleven thousand items and nine hundred filings a day and eighty-one open referrals and seven deaths in the first month and however many since would all have to go into it, in order, without excuse, in the language of a fault report, so that whoever received it at fourteen light-years and forty years' delay could weigh it themselves rather than being told what it weighed.

She hoped it would not be her. She thought, without much doubt, that it would be, and that she would be told it was an honour, and that she would say the same thing she had said to the Registrar of Instruments in a room three metres by four in the fifth month of Year 80, which was that she fixed things, and that this was a fault report.

At 0212 on the twelfth of the fourth month of Year 82, third shift, in the Quiet, with the lumens at eleven percent, Marisol Ibarra-Nakashima lay on her back in the crawl behind Frame 40 with her elbow in the guts of Photometric Channel Fourteen, replacing a preamp that had been drifting noisy for six weeks.

Two years, to the night.

"Fourteen, this is fourteen," she said into her collar. "Preamp's in. Bringing it cold."

"Copy fourteen." Not Pim; Pim had made Grade III in the first month and had a bench and a mouth on him still. A young man called Adaeze Oyelaran-Sant, nineteen, second month on shift, who chewed nothing and said sir to everybody until it had been beaten out of him. "You want the stack held?"

"Hold the channel out of solution for ten minutes. Don't hold the stack."

"Nav gets weird," said the boy.

"Nav gets weird," Sol agreed, with feeling.

The shunt took the cold beautifully. She watched the temperature curve fall away like a dropped rope, seventy kelvin, sixty, the noise floor going down with it into that clean black ridiculous quiet where a machine can hear individual particles of light arriving from fourteen light-years away.

And then the counts began, and Channel Fourteen sang to her, and she lay in the dark under the frame with her tools on her chest and her palm flat and still on her own thigh, and listened to something nobody had arranged.

The eclipse ingress came at a phase she had never heard. A flare at three minutes, fast rise, slow tail. Nothing for seven. Then two close together that she did not see coming and would never see coming, because it was a flare star, and that was the entire content of the phrase.

At 0240 she came out of the crawl and sat with her back against the frame and opened the work order that was still open, and went to the field at the bottom, and read what she had written in the seventh month of Y80, and added one line under it, because there was a boy at Frame 26 who would be licensed in eleven years and a girl in Nav who was printing eleven thousand lines of a machine shouting up her stairwell, and because the field said for the benefit of arrival and nobody had ever changed the wording and nobody ever would.

They answered. Somebody had been sending for thirty-eight years and we had it in a cupboard. Check the cupboards.

She thumbed it, and filed it, and stood up, and her knees complained, and she went forward into the Quiet, because there were eleven other channels and it was third shift and there was nobody else on it.

The rotary joint took two years, and the reason it took two years was that nobody aboard had ever made one.

It was a machined assembly the size of a bucket: two coaxial waveguide sections, one turning inside the other, with a choke gap of nought point four millimetres held true across a hundred and eleven degrees of travel, so that a sixteen-metre dish could be pointed without twisting its own plumbing off. There had been three of them at Departure. Two were in the aft holds as spares and had been robbed for their bearings in Y29 and Y44 by grades who had every right to rob them, since the transmit chain was passive and the bearings were the only ones of their size aboard and something else had needed them more.

Merced Ekwueme-Strand found the requisition for the Y44 robbery in the third month of Y83, nine weeks after she took the chief's stool, and brought it down to Frame 34 and put it on the trestle in front of Sol without a word, and they read it together.

One (1) bearing set, 210mm, angular contact, from spare assembly RJ-2, forward transmit chain. Chain is passive and there is no programme to restore it. Required for number four coolant circulator, Ribs Three. — B. OSEI, HULL STRUCTURES II.

"Y44," said Sol. "She'd have been thirty."

"She'd have been thirty and she'd have been right." Merced took the flimsy back and folded it in eighths, which everybody did now and which no one could remember starting. "That's what I want in the shop when we cut the leg. Not a speech. That."

The leg went on the fourteenth of the fourth month of Y83.

Descent Assembly Four, aft hold, one of eleven, four hundred and eleven tonnes between them: the landing gear of a ship that was going to set down on a world in Y197, forged in the Phobos yard out of the best steel anybody had ever put aboard, stowed in cradles and inspected every five years by a grade whose entire remaining function was to inspect them.

The work order was six pages. Merced wrote it herself and had it countersigned by four grades who had no standing to countersign anything, purely so that their names would be on it, and she sent a fair copy down to Frame 26, in an envelope, addressed to Mr T. Ibarra-Nakashima, apprentice-in-waiting, with a note that said: This is the first. There will be about four thousand more and most of them will be yours. Keep this one so you can tell people it was done badly. A.M.E-S.

Tico was eleven. He pinned it above his bunk beside the tracing of sheet nine, and he was, his mother reported, unbearable for a fortnight.

They cut it in the shop at Frame 8 with the doors open and about two hundred people on the gantry and the floor, which Merced had not wanted and had been unable to prevent. The steel came away in a fan of slow grey chips. Somebody in the crowd made a noise on the first cut and was hushed by three people at once, and after that it was only a shop, and a saw, and a woman in a leather apron who kept looking at her feed rate.

The bearing races came out of the third billet. The choke gap was held on the fourth attempt, after two years and eleven trial assemblies and one comprehensive failure in the ninth month of Y84 that put Comms back nine months and produced, on the wall of the Comms shop beside the ninety-year-old sign that said WE ARE NOT NAVIGATION, a second hand-painted sign that said RJ-4 WAS A LEARNING OPPORTUNITY, which Rosalind Achebe-Vantongeren refused to take down even after it stopped being funny.

The final amplifier was worse and took longer and is not interesting. It is in the record.

Chief Adaeze Ekwueme-Strand stood down at the end of Y82, at seventy-three, on the grounds that she could no longer get up the rolling ladder and that a chief who cannot reach the top of the wall is decorative. She spent eleven months in the Long Rib and died in the second month of Y84, and Forward Structures buried her in the Grove under a hornbeam in the fourteenth row, and Merced wrote the plate, and the plate said:

EKWUEME-STRAND, ADAEZE FOLASADE. Y09 – Y84. CHIEF, FORWARD STRUCTURES. SHE KEPT THE FABRICATION SET.

Naveen Duarte-Chatterjee died at his desk at Frame 35 in the seventh month of the same year, aged seventy-two, with a leave request half-signed under his hand, and Sol found that she minded it far more than she had expected to and could not work out why for about three weeks, until she was lying under Frame 40 at two in the morning and understood, with her elbow in a preamp, that he had read the paragraph about flux twice and decided not to see it and had signed anyway, and that this was the single most useful thing anybody had done for her in her life, and that she had never thanked him because there was no form.

She wrote it into the file afterwards. It went in as an annexed observation on WO-14C-0502-1, under the field marked FOR THE BENEFIT OF ARRIVAL, and it said: N. Duarte-Chatterjee, Optical V, signed this order on 2/5/80 having read page two twice. He did not have to. Nothing would have happened without it and there is no procedure that would have made him do it.

Osvaldo Prieto-Mensah finished the restoration on the nineteenth of the eleventh month of Y85.

Four thousand one hundred and six records, in five years and four months, back on the public board in full fidelity, every one of them indexed and cross-referenced and, where the box had rotted or the medium had failed, marked LOST — NOT RETIRED, which had been his own insistence and which had taken a Council determination to establish, because the distinction between a thing withheld and a thing destroyed by time turned out to matter enormously to about four thousand people and not at all to the eleven who had to write the software.

He came into the committee room at 2140 on the nineteenth with the ledger under his arm, as he had every Tuesday and Thursday for five years, and put it on the trestle and sat down and did not open it.

"That's the lot," he said.

"That's the lot."

"There's nothing to do on Thursday."

"There's the whole of the Y31 to Y44 acoustic block to re-index," said Sol, "because the Y31 to Y44 acoustic block was indexed by a man in Y47 who used a prefix system he invented on a Tuesday and did not write down."

Osvaldo Prieto-Mensah sat up.

"Do you know," he said, "I have never once been given a piece of work I could see the end of."

The Council spent nine days in the second month of Y86 deciding who had died of the publication, and it was, by common consent afterwards, the worst thing that body ever did, and the necessary thing, and it was necessary because of a transmission.

The argument had a shape that surprised nobody who had been paying attention. The Cerro Rico read four hundred and nine names, every time, in the first ninety seconds of every sequence, for seventy years. Whatever the Anabasis sent would have to carry its own figure or it would be worthless, because a number without a roll behind it is a claim, and the whole of what had gone wrong aboard this ship for ninety years was claims.

So: who counted.

Camila brought the Programme's paper on the first morning and stood at the rail of the speaking place and said, before she read a word of it, that the paper contained four candidate methodologies and that she believed all four of them to be indefensible and that she had written it anyway because somebody had to put the indefensible options in front of the Council in order for the Council to reject them properly.

The figures were these. In the twelve months from the twelfth of the fifth month of Y80, the Anabasis recorded two hundred and eleven deaths of all causes against a ten-year running mean of sixty-eight. Of the excess, ninety-one were self-administered and were unambiguous. Thirty-four were cardiac events in people over sixty, in a year in which the Programme's own sleep-aid dispensing had gone up four hundred and ten percent, and no physician aboard would sign a sentence connecting the two, and no physician aboard would sign a sentence denying it. Nineteen were accidents at work, in a year in which four thousand items a day were being handled by people who had not slept. The rest were the rest.

"You will want a threshold," said Camila. "There is no threshold. Whatever line this Council draws, it will draw across a family, and the family will be able to see it, and they will be right to."

They sat until the fourth day and got nowhere, and on the fourth day Councillor Ines Sorrentino-Mbeki, eighty years old, in her tenth term, took the floor for six minutes.

"We are trying to be accurate," she said, "and we are trying to be accurate because we are frightened of being accused of overstating, and we are frightened of that because we have spent ninety years living inside a number that was managed. I understand the reflex. I would like the Council to notice that it is a reflex."

She put both hands on the table.

"A person goes on this roll if their family asks for them to go on it. That is the whole method. Not a physician, not a coroner, not this Council, and above all not the Programme. The people who know whether a man died of this are the people who were in the room with him, and there is nobody else, and there never was, and every methodology in this paper is an attempt to take that judgement off them and give it to somebody with a grade."

"Then the number won't be true," said a member from Ribs Six.

"The number will be exactly as true as a number of that kind can be," said Sorrentino-Mbeki, "which is to say it will be a count of the people whose families are prepared to say out loud, in public, in perpetuity, in a record that goes to another ship, that this is what happened to them. There is no truer figure available in the universe. And I would remind the Council that we already know what happens when we decide to be accurate on somebody else's behalf: we get hypoxic event."

It carried by nineteen to three.

The applications ran for eleven weeks. Frame 19 handled them, because Frame 19 handled everything of that kind, and Yusuf Baptiste-Lindgren — thirty-five, senior keyworker, still working Tuesdays in the restoration room out of what he described as a filing habit — sat with two hundred and forty families across those weeks and did not once, by any account anybody ever gave, suggest an answer.

Sixty-one families declined. That was published too, as a figure and not as names, at Sorrentino-Mbeki's insistence: sixty-one families were asked and said no, and their reasons are their own, and the roll is therefore short by an unknown amount and always will be.

The final roll of the Anabasis, for the twelve months following the publication of the twelfth of the fifth month of Year 80, was one hundred and ninety-four names.

Two point one six percent of the complement, against the Cerro Rico's eleven point two.

Camila would not touch it. Sol watched her refuse to touch it for four months, in committee after committee, with a flat obstinacy that made two of her own directorate furious and cost her, in the end, a third refused promotion.

"Say why," said Sol, in the kitchen at Frame 26, in the ninth month, with bread rising under a cloth at eleven at night.

"Because everyone wants me to say it was the method." Camila was flouring the board and did not look up. "They want me to stand up and say: the Cerro told it as a truth and lost eleven percent, and we told it as a fault with a work order attached and lost two, and therefore my profession has learned something. And I do think we learned something. And I am not going to say it, because there is a much simpler explanation sitting in a green tin at Frame 61 and it is going to be in the transmission whether I like it or not."

"Say the simpler explanation."

"They had nobody," said Camila. "That's it. That's the whole of it. When the Cerro published in their Year Eleven, four thousand nine hundred people found out that everything was over, and there was not one voice anywhere in the universe that could tell them it was survivable, because nobody had ever survived it. When we published, there was a woman called Aurelia Mansour-Tekle in a cupboard at Frame Twenty-Two saying you can do this, it is very bad for about two years, and we did not even know she was there, and we still had her, because Bett Osei's nitrogen study was in the archive and Ilse Nakagawa-Bell's warning was in my doctrine appendix and every single useful thing in our first year came off that ship one way or another with the label torn off." She slapped the dough over. "They were the first. Nobody helps the first. We are not better than them, Sol, we are second, and being second is worth nine hundred people, and if I ever hear a Grade Two of mine claim that difference for the Programme I will have them off the grade."

The preamble committee sat for fourteen months and had nine members and produced, in the end, four hundred and ten words.

Sol was on it because she could not get out of it. Camila was on it because she was the only person aboard who had ever written something nine thousand people had to stand in. Jaiye Vance-Oyelaran was on it for the technical sections, and Rosalind Achebe-Vantongeren for the chain, and Kemi Odeleye-Vance because Sorrentino-Mbeki had put her name forward and had said, when asked why, because she maintained it and did not know, and there will be someone at the far end who maintained something and did not know, and they should hear from her.

The fights were not the ones anybody expected.

Nobody argued about including the ninety years. That was settled in the first session, in about eleven minutes, and it was settled by Kemi, who had said almost nothing for an hour and then said: "If we leave it out, then the first thing they learn about us is that we are the kind of people who leave things out," and the room had looked at her, and Camila had put her pen down and said, "That's the sentence. Somebody write it down as the standing test," and it was written down and it governed everything afterwards.

What they fought about was hope.

The Cerro Rico's Y41 transmission ended with a woman saying you can do this, and our children are not unhappy, and that is the whole of the encouragement I am able to offer and I am aware that it is thin. Sol had heard it forty times by then. It was the most useful sentence any human being had ever said to the Anabasis and it had sat in a safe behind four hundred pages for thirty-nine years.

And the committee could not write its equivalent, because they were six years in and did not know.

"We can't say it," said Achebe-Vantongeren, in the eleventh session. "We are seventy-nine years short of where they were when they said it. They had a hundred years of not dying behind them. We've got six and a mortality curve that's only just come back to the mean."

"Then we say what we've got," said Sol.

"We've got two point one six percent and a rotary joint."

"We've got the whole of pass one of the Survey," said Sol, "which is four hundred and eleven thousand items with the number in the box changed, and a list of nine thousand two hundred and six of them that fail before Y1080, and a nitrogen study that a woman filed under cleaning in Y58 because she was ashamed, and a measurement that says the sky is not eating us." She put her hands flat on the table. "That's not encouragement. It's better than encouragement. It's working, and the man on the Y79 tin said it in as many words — the list is the most valuable document we possess and we would trade the rest of this transmission for anybody else's. We have got somebody else's. We have got the only other one there will ever be."

Jae's finding was the piece that changed the shape of the thing, and it had come in during the fourth month of Y84, four years and one month after she had sat down on the grating at station three and said it's not going to work.

Twelve honest channels, four years of baseline, and the answer to the question nobody had ever been permitted to ask: the Anabasis was not decelerating. Not measurably. Not at three parts in ten thousand. The interstellar medium at seven hundred and forty-eight kilometres a second was doing effectively nothing to a two-kilometre spindle behind three hundred tonnes of Cap; the Cap's erosion at measured flux would take it into the fourth millennium; the aperture chamfers were due for their first reconditioning in approximately Year 3,240. She had published it in Instrument Note 84/119 with a title that Camila had said afterwards was the single most successful piece of communication ever produced aboard the ship, and which Jae maintained to her death was purely descriptive:

THE SHIP IS NOT SLOWING DOWN.

It had gone up on the board in the Bowl in type the same height as the velocity figure, and it had stayed there for nine days, and the Mood Index had come off the floor for the first time in four years and had never gone back.

"That's what we've got," said Sol, in the eleventh session, and Camila wrote it on the board at the end of the room, in the middle of nine other candidate closings, and nobody proposed a tenth.

The transmit chain went end-to-end on the second of the eighth month of Year 87.

They did the first radiating test at 0400 into a dummy load in the Frame 61 plant room, and it ran eleven minutes at four percent and the load got warm, and Rosalind Achebe-Vantongeren, fifty-six, put her hand on the casing and said, "That's a shop and a saw and a woman in a leather apron," and then went out into the passage and did not come back for a while.

The dish tracked for the first time on the ninth. The rotary joint held its choke gap through a hundred and eleven degrees and back, and Merced Ekwueme-Strand watched the whole travel from the gantry with her arms folded and pronounced it, at the end, "adequate," which the guild understood correctly and which Comms did not for about a week.

They pointed it on the departure bearing on the fourteenth of the eleventh month, and Jaiye Vance-Oyelaran, thirty-three, Astrometry I, gave them the pointing solution from twelve honest channels and four years of real parallax, and stood in the compartment while it was applied, and said, when Achebe-Vantongeren asked her to confirm it aloud for the log:

"Bearing confirmed on the Cerro Rico's departure solution, corrected for seventy-eight years of her own flight and eighty-seven of ours. Error at range, plus or minus one point one degrees. Her beam was nineteen degrees wide. She'll be inside it." A pause. "Ninety-one years, one way. Reply, if any, one hundred and eighty-two."

"Nobody in this room."

"Nobody in this room," said Jae. "Nobody in this room's grandchildren. That's not the point of it and everybody here knows it isn't."

They sent on the eleventh of the fifth month of Year 88, at 0630, after the Bell.

The Council had offered it to the eleventh of the fifth for the obvious reason and Camila had fought it for six weeks on the grounds that yoking the transmission to the Departure date made it an observance, and had lost, and had then written the schedule for it herself and made it, by every account, the best-run thing the Programme ever did.

Nine thousand two hundred people. There were more of them now than there had been in Y80; the birth rate had gone down for three years and then up for five, which was in the Cerro's data as well, in section five, in a table nobody had known how to read until they were living in it.

The Bowl was full and the concourses were full and the sound went to every deckhead. At 0630 the Bell rang, one note, low, and nine thousand two hundred people stopped for a second wherever they were, and the floor did not move.

Sol was in the compartment at Frame 61, four decks down and four hundred metres aft, because she had refused the Bowl and had been permitted to refuse it. There were seven of them in a room two metres by three: Achebe-Vantongeren at the chain, Jae at the pointing, Kemi at the log, Camila against the door with her arms folded, Merced on the deck with her back against the rack because there was nowhere else, and Tico — sixteen, four years into an apprenticeship, taller than his aunt, allowed in on the express written authority of the chief of Comms in a note that said he can hold the door and he will not touch anything — holding the door.

And Sol at the microphone, because the committee had voted it to her nine to nothing in the fourteenth month, and because she had said her piece about fault reports and had been listened to politely and overruled.

"Chain's up," said Achebe-Vantongeren. "Ninety-one percent. Dish is tracking. You're live when you speak, and it'll run until you stop, and I'd remind you the whole ship can hear you."

Sol looked at the four hundred and ten words on the flimsy in front of her, which she had known by heart for a year.

Then she turned it face down, because Aurelia Mansour-Tekle had not been reading, and began.

"This is the vessel Anabasis, transmitting on the departure bearing, sequence one, year eighty-eight of our voyage. This transmission is unaddressed. Anyone receiving may use anything in it. Nothing in it is proprietary and nothing in it is classified and we have no procedure for either.

"I am Marisol Ibarra-Nakashima, Hull Optical and Sensing, and I have the watch, and I am going to read the standing preamble, because the committee makes me, and because it is right that it should be read every time by whoever is holding the microphone.

"In the sixth year of our voyage a containment excursion in our aft drive destroyed our number three and four tankage, our injector array, and one thousand four hundred and twelve of our people. Its consequence was that the Anabasis completed its boost at approximately two and a half percent of the intended terminal velocity and cannot correct. Our arrival at the designated system does not occur. There is no trajectory available to this vessel that reaches any destination within the life of the hull, and the set of reachable systems closed sometime between our Year Sixty-One and our Year Sixty-Five, and we have known the date since Year Eighty.

"This information was withheld from our complement for seventy-four years.

"It was withheld by a vote of the whole ship's company in our Year Eleven, by approximately four to one, over three days. It was then maintained by an office of this vessel for three generations, by the substitution of recorded starlight for real starlight in all twelve of our astrometric channels; by the manufacture of false erosion witnesses on a machine which ran twice a year for sixty-one years; and by the retirement from the public archive of four thousand one hundred and six instrument records.

"It was maintained by good technicians doing scheduled tasks, in the dark, on a timer, and almost none of them knew. That is the part we most need you to hear, because if you are receiving this then you are a ship, and you have technicians, and you have a schedule.

"It ended on the eleventh of the fifth month of our Year Eighty. It ended because the record of a flare star repeated itself in the ear of a technician who had a habit of drumming, and because a chief of structures had kept a fabrication drawing for forty years, and because a maintenance technician of twenty-four opened a blank over an aperture with her own hands when she understood what she had been keeping. It ended in a work order about a chamfer.

"In the twelve months following publication we recorded two hundred and eleven deaths against a mean of sixty-eight. One hundred and ninety-four families have asked for their people to be named on our roll, and sixty-one families were asked and said no, and their reasons are their own, and the roll is therefore short by an unknown amount and always will be. I will read the roll at the end of this transmission as we will read it at the end of every transmission.

"We received your sequences four through one hundred and forty-two. We received them for thirty-eight years. Sixty of them were taken out of our public archive by seven successive holders of one office, individually, on sixty separate days, and put in a safe, and the only one of those people who ever wrote down why was Ilse Nakagawa-Bell, in our Year Forty-One, and what she wrote was that she had heard four thousand nine hundred people tell us how to survive and had put it in a cupboard.

"We are sorry. There is no version of that sentence that is worth anything and we are going to say it anyway, once, and then not again, because you did not send for an apology.

"We used your working. We used the nitrogen findings in section two of your sequence four and we did not know we were using them, because a Registrar took them out and introduced them under other cover, and the woman of ours who eventually rewrote them for our own hull filed her study under structural hygiene in our Year Fifty-Eight because she was ashamed to file it anywhere else, and her name was Bett Osei, and she is in our ground.

"We used your recertification methodology. We began our first pass in our Year Eighty and completed it in our Year Eighty-Six: four hundred and eleven thousand items, every grade, every bench, design life set at not less than one thousand years. Nine thousand two hundred and six items fail before that. The list is section three and it is the most valuable document we possess and we would trade the rest of this transmission for anybody else's, which is your sentence, and we are giving it back to you.

"We began cutting our descent assemblies in our Year Eighty-Three. Four hundred and eleven tonnes. The oldest argument aboard this vessel is whether we should have started sooner, and the answer is Year Seven, and everyone knows it, and it does not stop the argument.

"Our measured velocity is seven hundred and forty-eight kilometres a second, plus or minus two point one percent. Our position is provisional and will be provisional for another six years. Our design life is certified at not less than one thousand years, which is not a design life; it is a target, and our chief of forward structures said so from the floor of our Bowl before she voted for it, and she has a hornbeam in the ground now.

"Section four is a finding of ours which we do not believe is in any of your sequences and which we think you will want. Our astrometry has four years of true baseline. At our velocity, in this medium, we are not decelerating at three parts in ten thousand. The sky is not eating us. Our leading armour, at measured flux, requires its first reconditioning in approximately our Year Three Thousand Two Hundred and Forty. Whatever kills us, and something will, it is not the sand.

"We are, at the time of this transmission, in our eighty-eighth year, and there are nine thousand two hundred and eleven of us, and we are not dying. Our complement has been stable for six years and has grown for the last five.

"We do not know yet what to call this. Your Year Nineteen you stopped saying voyage and began saying the Long Build, and there is a proposal before our Council to adopt your term, and it has been sitting there for two years because a number of us feel it is not ours to take and a number of us feel that is precisely the sort of delicacy that put your sequences in a cupboard. It will be settled by a vote and I do not know which way I shall go.

"The remainder of this transmission runs to approximately eleven hours and repeats. It contains our full instrument record, restored, including the ninety years of it that were false, marked as false, so that you can see how it was done and check your own; our Survey pass one in its entirety; our mortality, morbidity and cohesion data, unredacted, including the first two years, which are the ones you will want; and our care taxonomy, with an annotation on category seven, which was our name for the condition of knowing.

"We have no expectation of reply within the lifetime of anyone now speaking. Ninety-one years out, one hundred and eighty-two for an answer. We send because somebody should have the working, and because we had yours for thirty-eight years and gave you nothing, and that is now over.

"If there is anyone else out there in the same condition as ourselves: you can do this. It is very bad for about two years. We are eight years in and it is still difficult and I am told by your people that it is difficult for about twenty. It is then, I am given to understand, simply your life. Our children are not unhappy. There is a boy holding the door of this compartment who was seven when we published and who has been an apprentice for four years, and when he was eight I told him he would never arrive anywhere, and he asked me what the point was, and I told him that four hundred tonnes of landing gear would have to be cut up by somebody, and he said he would write the work order. He did not write the first one. He will write about four thousand of them.

"That is the whole of the encouragement I am able to offer, and I am aware that it is thin, and I have borrowed the shape of it from a woman called Aurelia Mansour-Tekle, and if she is in your ground, we would be grateful to know it.

"Names for the roll, in the order they were given."

She read one hundred and ninety-four names.

It took nine minutes. She had practised it eleven times and had got through it twice, and this time she got through it, and the only one she stumbled on was the fourth, which was Rufino Adeyemi-Løkke, sixty-one, propellant gauge technician, who had gauged the tanks for thirty-eight years and never once asked what it was for, and whose three-line note was in section five with his daughter's consent.

At the end she said:

"We are still here. Anabasis, out."

Achebe-Vantongeren reached past her and put the payload into the chain, and the chain ran, and would run for eleven hours and then repeat, twice a year, on the departure bearing, for as long as anybody kept it up.

Nobody in the compartment said anything for a while. Somewhere four decks up and four hundred metres forward, nine thousand two hundred people were standing in a Bowl in the Highland wash under a deckhead lit for ninety years to look like weather, and Sol did not know what they were doing and found she did not need to.

Tico, sixteen, still holding the door, said: "You said my thing."

"I said your thing."

"You didn't say I said it badly."

"You said it perfectly," said Sol. "You said then what's the point, flat, and slightly angry, and it was the best sign I ever had."

She went forward that night, because it was third shift and there was nobody else on it.

The gallery was lit and railed and had a kettle at the aft end and a permit board at 5-A and a sign-in sheet with eleven names on it from the day watch. Twelve bays stencilled in white paint. Twelve open slits, two hundred and forty by eighteen, chamfered to nought point two, sharp as the day they were cut in a shed on Phobos.

At the aft end, on a stub of welding rod welded to the wall at a slight droop, the notebook hung on its loop of lanyard cord. Sol lifted it down and turned to the last written page.

Y88/05/11 — 0611 — pre-transmission check, all stations. No drift. Station 4 mount nut witness paint renewed. K. ODELEYE-VANCE, TA/MD.

And under it, in the same round hand, the next line already written, so the date would not be forgotten:

Y88/11/09 — autumn refresh —

Sol put her thumb on it and hung the book back on the nail, and went up the walkway to station fourteen, and clipped the portable head to the bracket, and ran the cold chain.

Seventy kelvin. Sixty. The noise floor going down into that clean black ridiculous quiet.

She sat on the grating with her back against the yellow rail and put the buds in and listened to the Lantern.

An eclipse ingress at a phase she had never heard. A flare at two minutes, fast rise, slow tail. Nothing for six. Then three in eleven seconds that she did not see coming and would never see coming, because it was a flare star, and that was the entire content of the phrase.

Her palm lay flat and still on her thigh. She had stopped trying, some years ago, and had found that not trying was better, and that it had taken her nineteen years of a recording and eight years of the truth to learn how to listen to something without wanting to own the pattern of it.

Ninety-one years out. One hundred and eighty-two for an answer.

Somewhere fourteen light-years away, or nearer, or further — the pointing solution said one point one degrees and the beam was nineteen wide and Jae had said she'll be inside it — five thousand two hundred people were doing something on a Tuesday, and would go on doing it for ninety-one years, and would then find out that they had not been sending into the dark.

Sol thought: they'll read us in a compartment. It'll be somebody's third shift.

She thought: they'll want to know if we made the choke gap.

At 0240 she pulled the buds out and took the head off the bracket and packed it, because there were eleven other channels and the day watch would want the bay clear, and she walked back down forty-one point two metres of walkway with handrails and lighting bosses, drawn by a woman on Phobos with a window and a view of Mars, closed out with a continuous weld, painted over four times by people who thought they were painting a wall, and opened on the eighth of the fifth month of Year 80 by a man with a battery grinder who had paid out somebody else's line.

At 5-A she signed out on the sheet, the way you did.

Then she went aft into the Quiet, with the lumens at eleven percent and the amber runners along the deck seams like the last coals of something, through a town two kilometres long inside a machine that was going nowhere at seven hundred and forty-eight kilometres a second and would have to become something else, slowly, over a thousand years, by hand, in files, at a rate that could be calculated.

At 0630 the Bell would ring. Nothing would burn.

The vote on the term came in the second month of Year 89, and it was the first thing the Council put to the whole ship's company since the publication, and nine thousand and eleven people voted out of a franchise of nine thousand three hundred and forty, which the Programme afterwards described as the highest participation ever recorded aboard and which Camila struck out of the draft and replaced with the sentence nine thousand and eleven people voted.

The question on the paper was: Shall this vessel adopt, for its own use, the term used by the vessel Cerro Rico from her Year Nineteen: the Long Build?

Sol had said in committee that she did not know which way she would go, and she had meant it, and she went into the booth at Frame 26 at 0710 on a Tuesday still not knowing, and stood there long enough that the woman behind her asked if she was all right.

What decided her was not an argument. It was that she had read one hundred and ninety-four names into a microphone nine months before and had discovered, somewhere around the eightieth, that she was reading them in a rhythm that was not hers. She had learned it off a recording. Every technician who had ever sat in the Instrument Gallery with the buds in had learned it off that recording: the pauses, the way you let a surname finish before you start the next given name, the flatness that is not coldness. Four hundred and nine names, first ninety seconds, seventy years. You could not use somebody's rhythm for nine minutes in front of your entire ship and then be too delicate to use their noun.

She voted yes. It carried, six thousand one hundred and four to two thousand eight hundred and ninety-one, with sixteen spoiled, one of which had written across it in block capitals ASK THEM FIRST, and which was reproduced in the record, because that was the sort of thing the record did now.

They asked them first anyway. It went out in sequence two, in the fifth month of Y89, in a paragraph of forty words near the end: We have adopted your term. It was carried six thousand one hundred and four to two thousand eight hundred and ninety-one. If it was not yours to give, tell us, and we will stop using it, and it will take you ninety-one years to say so and us ninety-one to hear it, and we will wait.

Thea Marchetti-Owusu stood down as Registrar of Instruments on the last day of the eighth month of Year 89, aged sixty-nine, having held the chair for twenty-five years, nine of them after the publication and sixteen before it.

She had been asked twice, formally, in Y81 and Y84, whether she wished to resign, and had said no both times, and the Council had not pressed it, because the Council had by then read her annex to Determination 80/D/1 — the recomputation she had done herself, on her own time, on the office's own machine, which showed the reachable set closing between Y61 and Y65 and which she had appended to the determination without being asked and without being able to say, when questioned, exactly why. There had been a party aboard who wanted her removed in Y80 and a party who wanted her tried, and neither had ever quite been able to explain what for, since everything she had done had been done under a standing instruction dated Year Eleven and countersigned by four thousand people who were dead.

What she had done was not make the call. She had said so in her own words to a committee, once, and never again: I could have stopped it in about an hour and I decided that it was not my hour.

The Council of Y89 debated for three days whether to abolish the office. The argument for was that it was the office of the lie; that it had held the safe, and the substitution machine, and the sixty tins, and seven successive holders had individually and privately taken sixty of another ship's sequences off a public board and locked them up; and that no institution which had done that should be permitted to keep its name.

The argument against was made by Kemi Odeleye-Vance, who was thirty-three by then and had been co-opted onto exactly one committee in her life and hated it.

"If you abolish it," she said, "you get a new office with a new name and no history, and in eighty years the person sitting in it will not know that the chair has form. Leave the name on the door. Make them read the file."

So the office survived, and with it a new instrument, which was a piece of paper about nine hundred words long that Thea Marchetti-Owusu was invited to write and did write, over six weeks, and which is read aloud by every incoming Registrar of Instruments at their installation, in public, from the floor, before they are given the keys. It is called the Induction and it is not a confession. It is a description of method. It sets out, in flat operational language, exactly how the substitution was maintained: which channels, which timer, which two weeks of the year the erosion machine ran, which grades were involved, how many of them knew, how the paperwork was made to look ordinary, and how long it took each new Registrar to stop feeling it. That last section is eleven lines and is the reason the thing exists.

The final paragraph reads:

You are now able to do this. The apparatus is gone but the position is not, because the position is not apparatus; it is one person with a signature and a reason. You will get your reason within about a decade. It will be a good one. It will arrive in the form of a real harm that you can prevent by withholding a real fact, and it will not look like Year Eleven, because Year Eleven does not look like Year Eleven when you are inside it; it looks like Tuesday, and like kindness, and like the responsible thing. I did not stop it. I recomputed it and filed the recomputation and went home. I am telling you this in the room, aloud, in front of your people, because the only working safeguard anyone has ever found is that they have all heard you say it.

She read it herself, first, at Jaiye Vance-Oyelaran's installation on the first of the ninth month of Y89, standing up, without the paper, because she had it by heart and because she had decided that the first person to perform the thing ought to demonstrate that it could be performed.

Jae was thirty-five. She was Registrar for thirty-one years.

Thea Marchetti-Owusu died in the fourth month of Y93 in the Long Rib, and there was an argument about the plate, because Forward Structures held that a plate states an office and a fact and nothing else, and because the obvious fact was not one anybody wanted to cut into brass. Merced Ekwueme-Strand settled it in the end by writing to the family and asking them, which was not procedure.

MARCHETTI-OWUSU, THEA. Y19 – Y93. REGISTRAR OF INSTRUMENTS. SHE DID THE ARITHMETIC AGAIN AND KEPT IT.

Sol went to it. There were about forty people, which was fewer than there should have been and more than she had expected. Afterwards she stood on the path between the hornbeams with Camila, who had come in her work clothes from a Programme meeting and would be going back to it, and who said, looking at the plate:

"She's the one I think about."

"I know."

"Not you. You had a machine that told you. She had a page of numbers and nine years of chair left and she did it anyway and then didn't move." Camila pushed her hair back with the flat of her wrist, the way she had since she was six. "I've done that. Everyone's done that. She's the only one with it on a wall."

The Mood Index was a number between zero and one thousand, produced daily by the Directorate of Programme from eleven inputs, six of which were unpublished, and it had been produced every day since the seventh month of Year Twelve, which made it, by Y89, the longest continuous data series aboard the vessel except the propellant gauges and the birth register.

It had never once been shown to the ship. It was shown to eleven grades. It set the lighting curve in the Bowl, the Highland wash cycle, the observance calendar, the confectionery allocation, the frequency of the Bell before there was a Bell, and — in the sixth year of Sol's life, though she did not learn this until Y86 — the decision to move an entire cohort's schooling forward by two months because the projected index for that quarter was one hundred and ten points below trigger.

Camila Ibarra-Nakashima brought the whole series to Council in the sixth month of Y90 — seventy-eight years, twenty-eight thousand five hundred and thirty daily values, the eleven inputs identified, the six unpublished ones named — and proposed two things.

The first was publication in full, retrospective and daily thereafter, on the public board beside the velocity figure.

The second was discontinuation.

"They are not the same proposal," she said, "and I would like the Council to reject the second one."

It rejected the second one. It took eight months about it and it rejected it, and Camila, who had proposed it, spoke against it four times, which caused a certain amount of comment among people who had never watched her work. Her position, in the end, was the position she had held since her thirties and had never got a hearing for while there was something to conceal: that a ship is a room with the door shut and nine thousand people in it, and that the temperature of that room is a real quantity, and that measuring it is not the offence. The offence is measuring it privately and turning the heating on without telling anybody.

So the Index survived, published, raw, with its inputs listed, revised methodology, no smoothing. And the ship, which had spent seventy-eight years being managed by it in the dark, spent about four years arguing with it in the light and then, largely, stopped looking. The daily value went up on the board in figures four centimetres high next to the velocity and the Survey completion percentage and the ground temperature in the Grove, and by Y96 the commonest observed behaviour in front of that board was a man glancing at the Index for a quarter of a second on his way to look at something else, which Camila described in her last doctrine paper as the correct amount of attention for a thermometer.

The Directorate of Programme was reorganised in Y92 into two branches, Observances and Care, with the Care taxonomy — including category seven, the condition of knowing — transferred to the physicians, and the whole apparatus of projection, trigger and intervention abolished as a class. Camila declined the directorship of both branches. She was, at the time of her death twenty-one years later, still Grade II, still writing the Bell schedule by hand four weeks in advance, and still, on the second Wednesday of every month, sitting in a room at Frame 19 with whoever had asked to be sat with.

Her plate says: **IBARRA-NAKASHIMA, CAMILA. Y42 – Y113. PROGRAMME, GRADE II. SHE SAID BR

...ING YOUR HANDS.

That is twenty-three years ahead of where this account has got to, and it is put down here out of order because Sol was the one who wrote the second line of it and she wrote it on the back of a Bell schedule, four weeks in advance, in her sister's own hand's worth of space, and because there is no later place in the record where it will fit.

The thing about the Ear was that nobody could remember it working.

It was a fourteen-metre offset paraboloid on the forward dorsal spine at Frame 61, installed in the Phobos yard, commissioned in Year Two, and it had brought aboard four thousand nine hundred people's working for thirty-eight years, and it had gone quiet in the eleventh month of Year Sixty-Six with sequence one hundred and forty-two, and for thirty years after that Comms had told itself, and told the Council, and told the archive, the sentence that everybody aboard had come to believe without ever once checking it: they stopped sending.

It was Yusuf Baptiste-Lindgren who found out otherwise, in the ninth month of Year Ninety-Five, on a Tuesday, in the restoration room, doing the sort of work he did on Tuesdays, which by then was cross-indexing consumables requisitions against the office diaries because Osvaldo Prieto-Mensah had insisted before he died that a requisition is an instrument record and had been, as usual, right.

Requisition 64/C/117. Third month of Year Sixty-Four. A consumables schedule of sixty-one line items, most of them lamps. Item forty-one read: Helium liquefier and transfer set, Frame 61 receiving chain (idle): release for reallocation, cold stores, Ribs Four. Initialled in the margin, in a small upright hand, T. M-O.

She had been in the chair eleven weeks.

Sol read it standing up in the restoration room at ten past nine at night with her coat still on, and read it again, and put it down on the trestle and stood with both hands on the edge of the table for about a minute, and Yusuf Baptiste-Lindgren, who had sat with two hundred and forty families and had never once suggested an answer, said nothing at all.

There was no annotation. There was no covering note. There was no minute in the office diary for that week except stores, lamps, the chief of Ribs Four re. the liquefier — settled. The word idle was accurate: the chain had been down since a preamplifier failure in Y62 which had been written up, correctly, and scheduled, correctly, and deferred, correctly, twice. Without cryogen you cannot cool a preamplifier. Without a cooled preamplifier a fourteen-metre dish at that range hears the inside of its own wiring. It is not a decision to go deaf. It is a lamp order.

"Do you want it in the file or in the Council?" said Yusuf.

"Both," said Sol, "and the Induction."

Jaiye Vance-Oyelaran, Registrar of Instruments, six years in the chair, thirty-nine years old, took it into the Council in the tenth month of Y95 herself, and read the line aloud, and then read the last paragraph of the Induction aloud after it, which she had by heart because she read it in public at every installation she ever attended, and which contains the sentence it does not look like Year Eleven; it looks like Tuesday, and like kindness, and like the responsible thing.

"She wrote that," Jae said, "and I have said it eleven times from this floor with her sitting in the third row, and neither of us knew that the best example in the whole of the record had her initials on it. I want the Council to sit with that for a moment, because it is the most useful thing that has happened to this ship since the publication. She was not hiding. She was not managing us. She was a competent officer eleven weeks into a job, signing sixty-one lines of stores at the end of a day, and item forty-one turned off the only other voice in the universe for thirty years, and she never knew she had done it, and neither did anybody else, and it did not require a conspiracy, and it did not require a vote of the whole ship's company, and it did not require anyone to be wicked at any point."

Somebody asked whether the plate should be changed.

"The plate is correct," said Jae. "Put the requisition in the Induction. Read them together. They are the same woman."

They were, from Y96 onward. Every incoming Registrar of Instruments reads nine hundred words of method and then reads item forty-one of a consumables schedule, and the ship has never once, in the century since, allowed the second to be dropped on grounds of length.

The rebuilding took eleven months and no fabrication to speak of, which was the part that hurt.

There was nothing wrong with the Ear. There had never been anything wrong with the Ear. The dish was true to within a millimetre and a half, the feed was original and dry, the waveguide run had been pressurised with nitrogen by a maintenance detachment twice a year for thirty years by people who had no idea what they were pressurising and who had, therefore, kept it perfect. The preamplifier from Y62 was on a shelf at Frame 8 in its box with the fault tag still on it. What they needed was a cryostat, and they had eleven of them, because Sol's own twelve honest channels ran on cold heads that Hull Optical had been rebuilding out of spares since Year Eighty, and the smallest of them was rated for four times the mass they had to cool.

Rosalind Achebe-Vantongeren, sixty-four, Chief of Comms and Telemetry for nineteen years, sat in the plant room at Frame 61 with the drawings across her knees and the sign that said WE ARE NOT NAVIGATION on the wall behind her and worked it out to the last fitting in one sitting, and then said, to Kemi Odeleye-Vance, who had brought the tea:

"Four decades. It was a lamp order and a bad preamp and four decades, and it is nine hundred kilos of plumbing, and I could have done it in Y80 with the crew I had, and it never entered my head, because I knew they'd stopped." She put the drawings down. "Write that in the notebook."

"It's not the gallery," said Kemi.

"Write it in the notebook."

It is in the notebook, in the gallery, out of place among the mount-nut witnesses and the autumn refreshes, in Kemi Odeleye-Vance's round hand: Y96/02/22 — Chief Comms states for the record: they did not stop. We stopped. R. ACHEBE-VANTONGEREN, per K. ODELEYE-VANCE, TA/MD.

They cooled the chain on the nineteenth of the second month of Year Ninety-Six and pointed the transmit dish — the same dish, the same rotary joint, the same choke gap held on the fourth attempt after two years and eleven trial assemblies, because a dish does not care which way the energy is going — on the bearing Jae had given them in Y87, corrected for nine years.

Then they listened for eleven days and heard nothing, which was expected, because the Cerro's cadence had never been better than quarterly and had been stretching for as long as anybody had records of it, and because — as Jae had explained to the Council in a single paragraph that Camila afterwards called the second-best piece of communication ever produced aboard — she is going away from us faster than anything else in the sky, and everything she says arrives late, and slow, and stretched, and redder every year, and there will come a year when the last of it goes under the floor of what we are able to build.

"How long?" the Council had asked.

"With this chain, about four hundred years," said Jae. "With a better one, longer. That is a fabrication problem and I would remind the Council that we have a thousand of them and about eleven hundred years."

It came in on the second of the third month of Year Ninety-Six at 0410, third shift, in the plant room at Frame 61, and there were four people awake in the compartment and one of them was there by accident.

Sol had come down because there was a preamp on the bench that belonged to channel nine and the bench at Frame 61 was warmer than hers. Rosalind Achebe-Vantongeren was there because she had been there every third shift for eleven days. There was a keyworker on the log whose name was Nadia Osei-Halvorsen, twenty-two, and there was Tico Ibarra-Nakashima, twenty-three, Structures II, who had come to bring his aunt a bag of bread from his mother and had stayed because nobody told him to go.

The carrier came up out of the noise like a wall coming out of fog. It was eleven decibels above anything the chain had ever seen and it sat there, steady, ridiculous, unmistakable, and Rosalind Achebe-Vantongeren said, in an entirely ordinary voice, "That's a machine."

Ninety seconds of preamble tone. Then a woman's voice, at the wrong speed, deep and slow and stretched by everything between here and there, and Sol reached over and did the correction by hand, on a dial, the way you would tune a shop radio, because that is what the equipment on that bench was, and the voice came up into a register a person could stand in, and said:

"This is the vessel Cerro Rico, sequence two hundred and sixty-two, on the departure bearing, unaddressed. Anyone receiving may use anything in it. Names for the roll, in the order they were given."

And then four hundred and nine names, at a pace Sol had known since she was twenty-two, in a rhythm she had read one hundred and ninety-four names in, in front of nine thousand two hundred people, eight years before.

It took ninety seconds. Nobody in the compartment moved. When the reader got to the third name Nadia Osei-Halvorsen began, without being asked, to write them down, which was unnecessary — the chain was recording — and which nobody stopped, and which is why the ship's copy of that roll is in a keyworker's handwriting on eleven sheets of log paper with the crossings-out left in.

At the end of the roll the voice said:

"This transmission runs to approximately nineteen hours and repeats. It is our one hundred and forty-eighth year."

Rosalind Achebe-Vantongeren put her hand flat on the casing.

"They're a hundred and forty-eight," she said. "Sol. They're a hundred and forty-eight and they're still cutting tape."

The Council was woken. It was the only time in the recorded history of the vessel that the whole Council was woken, including the two members who were in the Long Rib, one of whom came in a wheeled chair with a coat over her nightclothes and vo

...ted from it, and the sitting ran from 0520 until nine at night with a two-hour recess in which nobody went home.

What they were deciding was almost nothing. The chain was recording. Nineteen hours of it would repeat until it stopped repeating and there was no operational decision to make before the afternoon. What the Council was actually doing, and what its own minute says it was doing in a sentence Ines Sorrentino-Mbeki dictated before she died four years later, was sitting up with it.

It was their one hundred and forty-eighth year and there were three thousand nine hundred and eleven of them.

They had lost the eleven point two percent in their Year Eleven and Twelve and had gone on losing at above the mean for nineteen years after that, which was in section six, and which was the single most requested part of the whole transmission aboard the Anabasis for a decade afterwards, because it was the only document in the universe that said what the third decade looks like. Then they had flattened. Then, in their Year Forty-Four, they had gone below the mean and had stayed there, with one excursion in their Year Sixty-One that they attributed, in a table, to an outbreak of something respiratory and to nothing else, and they said so in the flat way of people who had learned not to be interesting.

They cut their descent assemblies in their Year Twelve, which the Anabasis had guessed and had never been able to confirm, and which cost the oldest argument aboard the ship nothing at all, because the answer had always been Year Seven and now everybody had a second wrong answer to compare it with.

They had done six passes of the Survey. Pass one in their Years Nine to Fourteen; pass six had closed the year before. The failure list at not less than one thousand years had come down from eleven thousand four hundred items to two thousand and nine, and the two thousand and nine were listed by bench, and against about four hundred of them there was a notation the Anabasis had to work out from context over the following fortnight, because it was not in any glossary they had ever been sent, and which turned out to mean no known method.

They had a Grove. They called it the ground. They had eleven thousand four hundred people in it.

They did not use the word arrival anywhere in nineteen hours. Not once, not as a negation, not as a thing renounced. Jae had a keyworker search the transcript for it twice.

And in the standing preamble, ninety seconds after the carrier, before the roll, in a voice that had been reading a fixed text for so long that the stresses had worn smooth in places, was this:

"We have been transmitting on this bearing since our Year Nineteen. We have received nothing, from anyone, ever. A proposal to discontinue this transmission was brought before our Council in our Year One Hundred and Thirty and was defeated by eleven votes, and the terms of the defeat are in section one, and the substance of them is that we hold it to be a maintenance task and not a hope, and that we do not discontinue maintenance tasks on the grounds that they have not yet been needed."

Rosalind Achebe-Vantongeren, who had heard it at 0412 in a plant room with three other people and a bag of bread on the bench, made them play those four sentences to the Council at 0530 before anything else, and then made them play them again, and then sat down.

"Eleven votes," she said. "In their Year One Hundred and Thirty. That is our Year Seventy-Eight. Two years before Sol found the flicker, four thousand people on another ship who have never heard from anybody sat in a room and voted by eleven to keep talking to nobody, and if it had gone the other way we would have cooled that chain in February and heard the inside of our own wiring for the rest of our lives and concluded, correctly, that they had stopped."

Somebody from Ribs Six asked what the difference was, practically, since the Anabasis's own transmission was in flight and would reach them regardless in their Year Two Hundred and Thirty-One.

"The difference," said Jaiye Vance-Oyelaran, Registrar of Instruments, "is a hundred and thirty-five years of their working, and the whole of their third decade, and the fact that we now know what happens to people who do this. And the difference is that in their Year Two Hundred and Thirty-One a woman who is currently about nine years old on that ship is going to be sitting in a compartment on third shift and a carrier is going to come up out of the noise, and every sentence in that preamble is going to stop being true, and we are the ones who did that, and we did it eight years ago, and it is already done, and there is nothing further required of us. It is in the post."

That was the sentence that went round the ship. Not the roll, not the complement, not pass six. Sixteen words, in the Bowl, on the board, under the Index and the velocity: IT IS IN THE POST.

The other thing, and it took Comms four days to say it out loud in a room with the Council in it, was the sequences.

The Anabasis had heard four to one hundred and forty-two. The Cerro Rico was now sending two hundred and sixty-two. One hundred and nineteen sequences had crossed a fourteen-light-year gap over forty years, arriving on schedule, at a dish that was true to within a millimetre and a half, into a feed that was original and dry, along a waveguide that a maintenance detachment had pressurised with nitrogen twice a year for thirty years, and had gone through a preamplifier that could not be cooled because a competent officer eleven weeks into a job had signed sixty-one lines of stores at the end of a day.

Forty years of another ship's third decade and fourth and fifth, their morbidity, their fabrication, their failures, whatever they had learned about no known method — arrived, and heard by nothing, and gone past at the speed of light, and gone.

There was a party in Council for calling them lost. Osvaldo Prieto-Mensah had been three years dead and his rule was on the board anyway, and it was Yusuf Baptiste-Lindgren, thirty-five in Y86 and forty-four now, who stood up at the back and said that the distinction had cost a Council determination once and he was not going to sit and watch it be given away in a minute.

The register entry, which is in the public archive under sequence gaps and which every keyworker aboard has copied out at some point in their training, reads:

Sequences 143–261 inclusive. One hundred and nineteen. Received at the aperture and not heard.
NOT RETIRED. NOT LOST. WE WERE ASLEEP.

Section nine of sequence two hundred and sixty-two was an index of their ground.

It was not a memorial. It was a plot register, benches and rows and a soil-management schedule, of the kind Forward Structures produced for the Grove every eleven years, and it had gone out in every sequence since their Year Eighty-One for the same reason the Anabasis had started sending the Survey list: because it was the largest well-kept document they had.

Sol found her on the sixth day, in the restoration room, at half past one in the morning, with Nadia Osei-Halvorsen asleep in a chair and the reader running.

MANSOUR-TEKLE, AURELIA. CR Y08 – CR Y79. CARE, ORDINARY GRADE. ROW 61, BENCH 4. NO PLATE AT FAMILY'S REQUEST.

She was seventy-one. She had been thirty-three when she sat in a compartment and said you can do this, it is very bad for about two years, and she had lived another thirty-eight years, and she had never held a grade above ordinary, and there was no plate.

Sol sat with that for a long time and then went and found, in the catalogue of their own transmission that the Cerro had appended to every sequence for a century and a half, the index entry for the recording itself: Y41 sequence 61, section 7 (care), item 3: personal statement, Mansour-Tekle A., 4 min 20 sec. Item three. Between an item two on dispensing protocols and an item four on the ventilation of shared sleeping compartments. Nobody on that ship had ever thought it was the important part. They had put it in because it was in the room and because they were the kind of people who did not leave things out, and it had gone into a cupboard at Frame 61 in Year Forty-One and had come out of a safe in Year Eighty and had been the shape of every honest sentence the Anabasis had managed to say since.

The proposal came from Kemi Odeleye-Vance, who had by then been co-opted onto four committees in her life and hated all of them, and it went through Council in a single afternoon with no opposition, and it was this: that the Anabasis ask nothing further and take nothing further, but record on its own ground, at its own expense, in its own row, a plate for a woman who was not in it.

Forward Structures held, as ever, that a plate states an office and a fact and nothing else. Merced Ekwueme-Strand, Chief, forty-nine, wrote it in a morning and did not consult anybody, on the grounds that she had asked the family once before, in Y93, and it had not been procedure then either.

It is in the fourteenth row, four places along from a hornbeam, in the ground of a ship she never heard of, and it says:

MANSOUR-TEKLE, AURELIA. CERRO RICO, Y08 – Y79. CARE, ORDINARY GRADE. SHE IS NOT HERE. WE HEARD HER ANYWAY.

They answered on the fourth of the fifth month of Year Ninety-Six, which was not a date with anything on it.

Camila had wanted it that way and had won, for once, without a fight, because the argument had shifted under everybody in the eight years since the first transmission and she no longer had to make it. The Anabasis sent twice a year and would go on sending twice a year, and now it also listened, continuously, on a chain that a keyworker checked every third shift, and the pair of activities together had stopped being an event and had become — the word is in the Council minute, and it is Merced's — a task.

They put the cadence up from two to four sequences a year in Y99, when the power budget allowed it, and to six in Y104, and there it stayed for two hundred years.

The Cerro Rico was heard in Y96, twice; in Y97, once; not at all in Y98; three times in Y99. Her cadence was ragged and getting redder and there were four years in the second century when nothing came and Comms kept the log anyway with the word NIL in it, six times a year, in eleven different hands.

Jae's paragraph, which she wrote at thirty-nine and never revised, is on the wall of the Comms shop under the sign that says WE ARE NOT NAVIGATION and beside the one that says RJ-4 WAS A LEARNING OPPORTUNITY:

She is going away from us faster than anything else in the sky. Everything she says arrives late, and slow, and stretched, and redder every year, and there will come a year when the last of it goes under the floor of what we are able to build. With this chain, about four hundred years. With a better one, longer. That is a fabrication problem. We have a thousand of them and about eleven hundred years.

The last unambiguous reception of the vessel Cerro Rico by the vessel Anabasis was sequence six hundred and eighty, in the ninth month of Year Four Hundred and Sixty-One, at a chain gain nobody in Y96 would have believed was constructible, by a Chief of Comms and Telemetry named Ferrão-Osei who was the sixteenth holder of that office since Rosalind Achebe-Vantongeren and who had been building toward it for her entire career. Their complement was three thousand three hundred. It was their Year Five Hundred and Thirteen. They had by then received one hundred and forty-two of the Anabasis's sequences and had been replying for two hundred and eighty years, and the two rolls were read at the head of every transmission in both directions, four hundred and nine names and one hundred and ninety-four, in the same rhythm, which by then nobody on either ship could have told you the origin of.

That is a long way past the end of this account and is put down here for the same reason Camila's plate was, which is that there is no later place for it.

Merced Ekwueme-Strand was Chief of Forward Structures for thirty-one years and stood down in Y114 at sixty-seven, on the grounds that she could still get up the rolling ladder and that this was not a sufficient reason to stay. She spent nine years in the shop at Frame 8 as an ordinary hand, which caused a certain amount of difficulty for two successive chiefs and which she declined to discuss. Her plate says: EKWUEME-STRAND, ANA MERCED. Y47 – Y127. CHIEF, FORWARD STRUCTURES. SHE PLOTTED THE POINT THAT WENT OFF THE WALL.

Kemi Odeleye-Vance kept the gallery notebook for fifty-one years. She had it from Y84, when Ruy Ferrão handed it to her without ceremony because he was going onto the day watch, and she gave it up in Y135 to a maintenance technician of twenty-three named Ilsabet Adeyemi-Løkke, who was the granddaughter of a propellant gauge technician who had gauged the tanks for thirty-eight years and never once asked what it was for and who is fourth on the roll. Kemi wrote her last line and then, as she had done for fifty-one years, wrote the date of the next one underneath it so that it would not be forgotten, and handed the book over with the pen still in the spine, and said the only instruction she ever gave about it, which was: "It's not a log. There's a log. This is so somebody knows what it was like."

She died in Y141, at seventy-seven. Her plate says: ODELEYE-VANCE, KEMI. Y64 – Y141. TRUST MAINTENANCE DETACHMENT. SHE OPENED THE BLANK HERSELF.

Tico Ibarra-Nakashima became Chief of Forward Structures in the sixth month of Year One Hundred and Nineteen, at forty-seven, and held it for twenty-six years, and in that time his guild cut and dressed and stowed nine of the eleven descent assemblies, four hundred and eleven tonnes of the best steel anybody had ever put aboard, into forty-one thousand items of frame, bracket, spar, race, plate and pin, of which the great majority is still in service and about eleven thousand pieces of which are in the walkway gratings of the Instrument Gallery, the Long Rib, and the Grove. He wrote, by the reckoning of a keyworker who counted them for a wager in Y160, four thousand three hundred and eleven work orders.

He kept two things above his desk for the whole twenty-six years. One was a tracing of sheet nine of a fabrication set. The other was a six-page work order for Descent Assembly Four, dated the fourteenth of the fourth month of Y83, countersigned by four grades who had no standing to countersign anything, with a note attached that said This is the first. There will be about four thousand more and most of them will be yours. Keep this one so you can tell people it was done badly.

He told people it was done badly. He told them for twenty-six years. It is on his plate, because his apprentices insisted, and Forward Structures held that a plate states an office and a fact and nothing else, and lost:

IBARRA-NAKASHIMA, PATRICIO. Y73 – Y151. CHIEF, FORWARD STRUCTURES. HE SAID THEN WHAT'S THE POINT.

Camila died in the fourth month of Year One Hundred and Thirteen, at seventy-one, in the Long Rib, on a Wednesday, which she said from the bed was inconvenient because it was the second Wednesday and there was a woman at Frame 19 expecting her. Somebody went and sat with the woman. Camila approved the arrangement, in writing, at eleven in the morning, in her own hand, on the back of a Bell schedule that was already drawn up four weeks in advance.

Sol wrote the second line of the plate on the same sheet, on the reverse, in the space her sister had left.

The Bell rang at 0630 the next morning, one note, low, as it had every morning for thirty-three years by then and has every morning since, and nine thousand and some people stopped for a second wherever they were, and the floor did not move.

Rosalind Achebe-Vantongeren died in Y108, Chief of Comms and Telemetry for thirty-one years, and left instructions that the sign saying RJ-4 WAS A LEARNING OPPORTUNITY was not to be taken down. It is still there. It has been repainted eleven times and the guild has an argument every generation about whether repainting it counts as taking it down.

Jaiye Vance-Oyelaran was Registrar of Instruments for thirty-one years and read the Induction and item forty-one of consumables requisition 64/C/117 aloud, in public, from the floor, at fourteen installations, twelve of them not her own. She stood down in Y120 and lived until Y138 and spent the last eighteen years doing parallax work with four honest channels and a chair, and the position she established in Y124 — that the Anabasis's position was no longer provisional, and had not been provisional since Y94, and that the Council should stop saying it was — was carried on the fourth attempt in Y127, three years after she had stopped attending.

The wall in the Bowl now says the position. It has said it for two hundred years. Nobody looks at it, which is the correct amount of attention for a position.

WO-14C-0502-1 was never closed.

It was raised on the second of the fifth month of Year Eighty by Marisol Ibarra-Nakashima, Hull Optical and Sensing IV, against station fourteen of the Instrument Gallery, in respect of an aperture chamfer, and it was countersigned by a man who read page two twice and did not have to, and it acquired, over the following hundred and twenty years, four hundred and eleven annexed observations, a mortality roll, a nitrogen study filed under structural hygiene by a woman who was ashamed, a consumables requisition with sixty-one lines on it, a recomputation of a reachable set, and the whole of the Survey.

There was a motion to close it in Y118 on the grounds that the fault had been rectified in Y80 by a man with a battery grinder. Sol was sixty-nine and did not attend. She sent four lines, which the Council had read into the minute by a keyworker and which are annexed to the order as observation number two hundred and six:

The fault was not the chamfer. The chamfer was rectified on 8/5/80 and I signed for it. The fault is that a competent person doing a scheduled task in the dark cannot tell the difference between maintaining a ship and maintaining a story about a ship, and there is no procedure that fixes that, and there is no date by which it will have been fixed. Leave it open. It costs one line in the index. It is the cheapest thing this vessel does.

It is still open. It is the oldest open work order in the record and there are now, at the time of this account, one hundred and nine thousand of them, and it is first.

Sol worked third shift for fifty-one years.

She was offered the chief's chair in Hull Optical four times and took it once, for nineteen months in Y101 and Y102, and was, by every account including her own, poor at it, and went back to the twelve channels and the cold heads and the walkway with the handrails. She trained forty-one technicians. She never once, in fifty-one years, told any of them the story unprompted; she told them the method, and made them run the cold chain by hand before she let them near a keyboard, and made them sit through a full ingress and egress on the Lantern with the buds in and nothing to do, which about half of them complained about to the guild and none of them dropped from the syllabus when they came to write it themselves.

She was Custodian of Restoration until Y99 and then gave it to Yusuf Baptiste-Lindgren, who held it for twenty-six years and gave it to a keyworker named Nadia Osei-Halvorsen, who had written down four hundred and nine names on eleven sheets of log paper at four in the morning when she was twenty-two because nobody stopped her.

She read the preamble into the transmitter eleven times in fifty years, whenever the rota fell to her and she was well enough to walk to Frame 61, and she turned the flimsy face down every time, and she never got faster at the roll.

In the ninth month of Year One Hundred and Twenty-Six, at seventy-eight, she wrote to the Registrar of Instruments and to the guild and asked to be taken off the rota at the end of the year, and gave as her reason that she had begun, twice in four months, to hear things in the noise floor that the recording did not contain, and that she had checked, and that this was the correct time to stop.

The guild gave her the last watch of the year. She had asked for it not to be an observance and it was not an observance; the rota simply had her name on the thirty-first, third shift, station fourteen, as it had had eleven times that year and about nine hundred times before.

She came up through the Quiet at ten past eleven with the lumens at eleven percent and the amber runners along the deck seams, past the hatch at 5-A, and signed in on the sheet the way you did.

The gallery was lit and railed. There were fourteen names on the day sheet. Twelve bays stencilled in white paint, twelve open slits, two hundred and forty by eighteen, chamfered to nought point two, sharp as the day they were cut in a shed on Phobos by a machinist whose name is on a fabrication set that hangs in the shop at Frame 8 in a frame.

At the aft end, on a stub of welding rod welded to the wall at a slight droop by nobody anybody could ever identify, the notebook hung on its loop of lanyard cord. Sol lifted it down, which took both hands now, and turned to the last written page.

Y126/12/29 — 0140 — stations 1–12 walked, all clear. Station 9 lamp boss loose, tightened, witness renewed. I. ADEYEMI-LØKKE, TA/MD.

And under it, in the same hand, the next line already written, so the date would not be forgotten:

Y127/02/21 — winter refresh —

She put her thumb on it and hung the book back on the nail.

She had a young technician with her, because she had one every watch now and had done for nineteen years, and this one was called Bassam Marchetti-Owusu, and was twenty, and was three months in, and had a habit of drumming on things that Sol had noticed on the first night and had said nothing about.

They walked the twelve stations. It took an hour and ten. At station four they renewed the mount-nut witness paint because it was thin, and at station seven the boy asked, as they all asked eventually, whether it was true that you could hear the difference, and Sol said that you could not, that nobody could, that the difference was seven parts in ten thousand and no ear in the history of the species has ever resolved seven parts in ten thousand, and that what you could hear was a repeat, and that a repeat is not a difference, it is a sameness, and that the entire apparatus of ninety years had been defeated by the one thing a machine cannot help doing, which is the same thing twice.

"Then how do you catch it now?" he said. "If they did it again. Better."

"You don't," said Sol. "Twelve channels, four thousand hours of baseline, and a Registrar who reads a lamp order out loud in public before they get the keys. That's it. That's the whole of the defence and it is thinner than people think and it has held for forty-six years." She screwed the lid down on the witness paint. "The thing that catches it is that you sit here. Not that you're clever. That you sit here, on the thirty-first, when there's nothing on."

At station fourteen she clipped the portable head to the bracket herself, because it was hers and she was still able to, and ran the cold chain.

Seventy kelvin. Sixty. The noise floor going down into that clean black ridiculous quiet, the way it had at station fourteen on the twenty-ninth of the fourth month of Year Eighty, when a woman of forty-nine had sat down with a preamp in her lap and a habit of drumming and had heard an eclipse ingress at a phase she knew, and then a flare at two minutes, fast rise, slow tail, and had put her palm flat on her thigh and had waited eleven seconds for three that she already knew were coming.

She sat down on the grating with her back against the yellow rail. The boy sat on the other side of the walkway with his knees up because there was nowhere else, which there never had been.

"Buds in," said Sol. "Don't say anything for six minutes. You'll want to. It's a flare star, it will do nothing for six minutes and then it will do three things in eleven seconds, and if you talk you'll miss the ingress and I am not staying up to do it twice."

He put the buds in.

It was 0210 on the last night of the year and there were about nine thousand four hundred people asleep in a town two kilometres long inside a machine that was going nowhere at seven hundred and forty-eight kilometres a second, and one hundred and nine thousand open work orders in a file, and eleven thousand pieces of a landing gear in the walkway gratings under them, and a woman four rows into the Grove with no body in the ground and a plate that said WE HEARD HER ANYWAY, and a carrier fourteen light-years out, redshifting, quarterly, ragged, that would be audible for another three hundred and sixty-five years to anybody who kept building the chain.

The Lantern came up in the buds.

An eclipse ingress, at a phase she had never heard, in the eleven-year cycle of a real star doing it in real time. Then nothing. Then a flare at four minutes, fast rise, slow tail, longer than any she had catalogued, which she noted for the day watch on the pad on her knee in a hand that had got worse and was still legible.

Then nothing for a long time.

Sol's palm lay flat and still on her thigh. She had stopped trying, some years ago, and had found that not trying was better, and that it had taken her nineteen years of a recording and forty-six of the truth to learn how to listen to something without wanting to own the pattern of it.

Beside her, in the dark, the boy of twenty began, very quietly, without knowing he was doing it, to drum four fingers on the grating.

She did not stop him.

At 0248 the star did three things in eleven seconds that neither of them saw coming and that nobody would ever see coming, because it was a flare star, and that was the entire content of the phrase.

At 0310 she pulled the buds out and took the head off the bracket and packed it, because there were eleven other channels and the day watch would want the bay clear. She walked back down forty-one point two metres of walkway with handrails and lighting bosses, drawn by a woman on Phobos with a window and a view of Mars, closed out with a continuous weld, painted over four times by people who thought they were painting a wall, and opened on the eighth of the fifth month of Year Eighty by a man with a battery grinder who had paid out somebody else's line.

At the aft end she lifted the notebook down and made her last entry in it, under the boy's watchful and slightly embarrassed silence, in a hand that had got worse and was still legible.

Y126/12/31 — 0310 — station 14, cold chain run by hand. Lantern: ingress at unrecorded phase; flare at 4 min, long tail, catalogue it; three at 0248 in eleven seconds. Nothing repeated. Nothing ever has.
Handing over. It has been forty-six years and I am satisfied that it is somebody else's turn to sit here on the thirty-first when there is nothing on.
M. IBARRA-NAKASHIMA, HULL OPTICAL & SENSING IV.

Then, because it was the practice of the book and had been since a woman with a round hand started it and had never once been written down as a rule, she wrote the date of the next line underneath, so that it would not be forgotten.

Y127/02/21 — winter refresh —

She hung the book back on its nail, on the stub of welding rod welded to the wall at a slight droop, and put her thumb on the page a second, and left it open at that line for whoever came next.

Then she signed out on the sheet at 5-A, the way you did, and went aft into the Quiet.

At 0630 the Bell would ring. Nothing would burn.