Silence

The timing mattered.

Not the timing of the cut — that was mechanical, a matter of two switches and a count — but the timing of what she sent before it. She had forty-one minutes and a lexicon built in four hours by three exhausted people who had never done anything like this and a spectrometer that was never designed for what she was asking it to do.

She went back to the sub-basement.

Eriksson was sitting against the wall. Mafi was still at the spectrometer. Paulsen had fallen asleep in the corner with his back against the thermal insulation and his arms around his knees, and for the first time in hours he looked like someone who was resting rather than enduring.

"I need to send something," Nadia said to Mafi. "Terminal signal. End of exchange."

Mafi looked at her. "If we close the conversation — "

"I know. But if the emitters come online, it needs to know that what comes next isn't us." She thought about how to explain what she was about to do. "If something caused you pain and then went silent before the pain started, you might understand the silence as a boundary. As — regret."

"That's a significant attribution."

"Everything I've done in the last six hours is a significant attribution." She held out her hand for the recorder. "It answered three-and-two. It compressed its response interval to near-zero when Holm's work suggested it might be being heard. Those are not the behaviors of something that doesn't understand communication is happening." She looked at Mafi steadily. "I'm not willing to let the last thing we say to it be the sound of a weapon cycling up."

Mafi handed her the recorder.

Nadia thought for a moment about what she wanted to say. The lexicon was crude. The terminal signal was a silence held past the expected interval — not an active transmission, but the absence of one. A pause long enough to mean finished.

She sat cross-legged on the cold floor.

She produced the interrogative structure — the closest thing they had to an expression of want. Then the acknowledgment signal: single modulation, I hear you. Then she held the recorder open and let the silence run.

Thirty seconds. Forty. Fifty.

The sensors registered nothing on the 18.98 band.

Then, at fifty-eight seconds: a response.

Not the complex layered structure it had been building toward. Something simple. Single modulation. The acknowledgment structure.

I hear you too.

Nadia set the recorder down.

In the central module directly above them, she heard the technicians finishing their calibration. The low hum of the emitter units running at standby. Veld's voice giving an instruction she couldn't make out through the floor.

She looked at Eriksson.

"Now," she said.

He stood up and moved to the access ladder without a word.

Nadia went to the generator room.

She found the two breaker positions Holm had mapped.

She put her hands on both switches.

She counted to three.