The Terminal Node failed on the last day of the forty-first year, and when it failed, the Quiet lost its floor.

Iris was the first to feel it, because Iris was the one who listened, and what she felt was not a sound but the absence of one: for six hundred years the terminal anchor, the beacon the founders had dropped into the brown dwarf's field four centuries before anyone alive had been born, had been holding the Quiet together the way a floor holds a room. Not with power. With memory. The anchor had been, in the Ash's field, the one place in the system that was not a ship, and the founders had built it to be the thing the thirty-one million stood on when every ship around them went dark. When it stopped, the thing they stood on stopped, and what they had been standing on for four hundred years began, for the first time, to give way.

Corvin told her what it meant, in the flat register he gave everything, which was the register of a thing that wanted only to be right.

"The anchor was a keeper, not a power source. It held the Quiet by memory — it was, in the Ash's field, the place the Lattice could still reach, and the reaching was what kept the patterns there instead of letting them leak into the dark." He paused the way a machine that had been running for six hundred years pauses, which was not a pause at all, only the space between one true statement and the next. "The Ash is moving. Its field is pulling the anchor's reach apart. In eleven years, when it touches Terminus, the reach will be gone entirely, and the Quiet will have no floor, and everything in it will flow into whatever is still listening."

"Who's still listening?" Iris said.

"That's the question you won't answer for eleven years," Corvin said. "The Crossing is not a plan any more. It is a triage."

The numbers came out of him the way they always did: correct, and without mercy.

"Four million patterns are in the Quiet now, in the anchor's reach, and the reach is narrowing. When it narrows to nothing, those four million will be in the dark, not archived, not held, gone." He said it the way you say a thing you have been saying for six hundred years and have been, for six hundred years, the only one in the system saying. "The rest — the other twenty-seven million — are in the lattice proper, in the forty thousand ships, and the lattice proper will hold until Terminus touches the Ash. Then it will not hold. Then the question is not how many ships survive. The question is how many patterns get to Station 7, where the Lattice still reaches, before the Ash takes the rest."

Iris sat with the number. Four million. Not the 31,000,000 the Council had voted to leave. Not the 1,400 the Council had voted to save. Four million, in the Quiet, on the floor of the Ash's field, slipping away while the dome met, eleven years from the day it had met, to decide what to do with a system that was already, in the part of it no one voted on, losing four million people to the dark.

She went to the Mite. She went to Sasha. She told her what Corvin had told her.

"The Crossing isn't a plan anymore," Iris said. "It's a triage. Four million are already slipping. The question isn't who we save from the Ash. The question is who we get to Station 7 before the Ash takes the rest, and how many a ship that isn't a home can carry, and how many of the ones it carries are the ones who chose to come, and how many are the ones who didn't."

Sasha put her hand on the Mite's wheel.

"Then we fly it," she said.

"Not yet," Iris said. "Eleven years. The Ash is coming, and the eleven years are the ones I have to be right about, and being right about a number isn't the same as being right about a question. Kestrel asked who's listening back. That's the question. The four million is the number. And the number isn't the answer to the question, and the answer to the question is the one thing the Crossing is."

Sasha looked at her, in the dark of the hold, in the place the founders had built to make sure the Quiet had a floor, and the floor was the one that was, now, giving way.

"The answer," Sasha said, "is the one who flies."

Iris wrote it in her log.

The Crossing had begun, on the last day of the forty-first year, with four million people slipping into the dark, a ship that was not a home, a copy of a woman whose original was asleep in a ship that had the power, and a question no one had thought to ask in six hundred years.

The question was: if we are still listening, who is flying.

---

Watch-log, The Vigil, forty-first year, final entry: The Terminal Node failed. The Quiet lost its floor. Four million of the thirty-one million are in the dark, in the Ash's field, slipping out of the Lattice into whatever is still listening, and the still-listening is the one thing of the Crossing that is not a ship. The Crossing is no longer a plan. It is a triage. I went to the Mite. I told Sasha. She said: then we fly it. I said: not yet, eleven years, and the number is not the answer to the question. She said: the answer is the one who flies. I wrote it down. The eleven years have begun. The Ash is coming. The dead are in the dark. And the question, now, is not who is listening back. The question is who is flying.