Imager Fault

This is logged the way things are logged on Fliade: by someone who was there, into a unit that was there too, and read afterwards by someone who was not. This season the reading afterwards is the whole of it.

Aravena knocked.

That was the job now, or the part of it that was Aravena's and nobody else's. Every shift, before anything: pick a stone at the junction, a good one, the size of two hands, carry it to the front down the third passage, through the squeeze sideways with the stone turned lengthwise and the side scraping, out onto the silt with the light held low. Kneel. Set it on the line. Step back. Wait.

And every shift, the one on the line bent, and put a hand to a rock at the edge of the silt, and moved it, and the ground said so through the silt and Aravena's boots.

A year of that. A hundred and some shifts, and the party had stopped counting, because a count is for things that might stop. The one on the line was there every time, in the open, still, grey against the stone, large, and did not withdraw and did not come nearer, and Aravena could not have sworn it was always the same one, because the party had never learned to tell the adults apart, and would have sworn it anyway. You know a person by how they stand. This one stood like a person who had decided where to stand a long time ago.

Aravena said the thing, too, every shift, facing the one on the line, going up at the end. It was not in the log and never would be. Then back through the crack, not running, and up to the junction, where Egede had the imager out of its case and Nakagawa was reading the ground, and the shift could begin.

"Log," said Aravena, kneeling to the unit. "Shift one-one-seven. Upper junction. Party of three. Knock answered."

The unit hummed, once, low, to say it had heard. Aravena still liked that.

Behind them, down the third passage, was the dark, the real kind, and the party kept its back to it while it worked, which was the rule, and which was not the same as forgetting it was there. Egede at the far wall with the imager, saying things. Nakagawa standing still. Aravena logging the temperature, twice, from habit. The Anstolik had not been through. Nothing had. Then the working time was over, the way it always was, and they gathered the light and the handsets and left the unit asleep, and the imager, which stayed now, on its stand at the far wall, facing the junction, because Egede wanted the room while the party was gone.

They went up the long passage toward the cold, all three, talking.

Nakagawa read the channels every evening at the station, after the others had eaten, because a thing read the same day is a thing you can still do something about. Sound channel, nothing. Thermal, nothing after the party left. Imager.

Nakagawa ran the imager's playback twice, and then sat for a while, and then went and got the other two.

"Look at that," said Nakagawa, and pointed.

At the mouth of the third passage, at the edge of what the working light had reached before the party took it away, in the fungus-dark the imager could just work by: a shape. Dark. Upright. About the size of a person. Still. It had an edge. That was what Nakagawa had sat with: not that it was dark, since the dark was dark, but that it had an edge, and the edge was lit, thinly, all the way round, the way a thing is lit when the light goes round it instead of onto it. It had arrived between one frame and the next, and stood for forty seconds, and was not there.

"Thermal," said Egede.

"Nothing."

"Sound."

"Nothing."

"Mass."

"Nothing. Nothing on any channel but the one you are looking at."

Egede looked at it for a long time, and Nakagawa watched Egede look, and saw the moment the explanation arrived, because it arrived the way Egede's explanations did, all at once and with relief in it.

"That's a dead region," Egede said. "That's the imager. A sensor block dropping out. It reads dark because it's not reading. You get a hard edge because the block has a hard edge. It's not a return, it's an absence of return."

"The thermal channel also has an absence of return there."

"The thermal channel is a different instrument. A warm thing in that spot would show. Nothing shows. So nothing's there, and the imager has a fault. I'll recalibrate in the morning."

It was a good explanation. Nakagawa had been doing this long enough to know that the trouble with a good explanation is that you stop looking at the thing it explains. "Log the fault," Nakagawa said. "And log the shape. Both. Where it was and how long, and the edge."

"The edge is the block boundary."

"Then it will be the block boundary in the log, and when you've recalibrated, we'll see."

Aravena had said nothing. Aravena was still looking at the screen, at the place where the shape had been, after it was gone, and Nakagawa noticed that, and put it aside.

Egede recalibrated, and for six shifts there was nothing, and Egede was pleased, and then there was.

Same place. Twenty seconds this time. Then four shifts of nothing and then two minutes. Egede changed the lens. It came back. Egede took the imager up to the station and ran it against the test card for a whole evening and found nothing wrong with it and said so, with the particular irritation of a person whose instrument will not be broken when told to, and took the spare imager down instead, the one that had sat in its case since the first year.

The spare saw it too. Same place. Same edge.

"Then it's the mount," said Egede. "Or the fungus. Or there's a cold spot on that wall doing something to the optics. I don't know what it is. I'm investigating."

Seven times, in seven weeks. Nakagawa kept the count, in the file, beside the entries, the way Nakagawa had kept the count of shifts on which nothing happened, and for the same reason: so that on the day it mattered, the file would say how long it had already been true. Each entry was in Egede's hand. Imager artefact, third passage mouth, cause under investigation. Seven of them. Honest, every one, and each one a reading entered as a fact, and Nakagawa had let them stand, and knew it.

The manifest came round in the middle of it, because the manifest came round at the turn of every year on the ground and did not care what else was happening. Every instrument on the station listed, checked, signed for. Egede did the rack. Nakagawa did the signing.

Third shelf. A unit the party had not installed: squat, sealed, humming very slightly, with a boundary-side seal on its case and a boundary-side marking on the manifest line. It had come with the station, under the protocols that applied to this planet because of the feature under study somewhere near it, which the survey had never been told the nature of and did not need to know. A gravimeter. Dormant, meaning powered and logging and not the survey's to touch. It had been logging since the first year. Its log was not the survey's to read.

"Gravimeter, boundary-side, nominal," said Egede, and ticked it.

Nakagawa signed. It was not theirs. It was logging. That was all the manifest asked, and all the manifest had asked the year before, and Nakagawa signed it and went to the next line and did not think about it again that evening, and would, later, remember exactly the tick, and the pen, and the hum.

Nakagawa asked, at last, the way Nakagawa had asked about the unit at the line a year before: plainly, at the station, after the others had eaten, with the playback up.

"You have not said one thing about that in seven weeks," Nakagawa said. "And you have looked at it longer than either of us. Every time. What is it you are looking at?"

Aravena had known the question was coming and had not got any better at it.

"Where it is," said Aravena.

"The third passage mouth."

"The edge of the light. Where the light stopped, the first year, before we had the stand. Where he stood." Aravena did not say Teddy; Nakagawa had let the word go for a year and Aravena had stopped using it anyway, without deciding to. "The eleven minutes. It's the same place. Not near it. The same."

Nakagawa did not say anything for a moment, and then pulled the second-year file, and put the thermal profile from the eleven minutes beside the imager frame, and looked, and Aravena watched the survey lead see it.

"Yes," said Nakagawa. "It is."

"He was warm. That was the whole of what we had. A warm thing, standing. We never saw him. We saw his warmth. This is the other way round. We see it. It isn't warm."

"So it isn't him."

"No. It's where he stood."

"That is a place," said Nakagawa, "not a reading."

"It's a fact," said Aravena. "File it."

Nakagawa filed it, in Aravena's words, and then waited, because Nakagawa could tell when there was more.

"The other thing," said Aravena, "is the knock. I go down every shift and I set the stone down and the one on the line moves the rock. Every time. A year. Nothing else has ever answered a stone. Nothing else has ever moved one. Whatever this is on the imager, it doesn't do anything. It doesn't move. It doesn't answer. It's there, and then it isn't. The unit at least hummed." Aravena stopped, because the next part was not a reading either. "Egede says a fault. A fault doesn't have an edge the light goes round. Look at it. The light is going round it."

"Egede has looked at it."

"I know."

"Then what is it?"

"I don't know," said Aravena. "I'm not saying I know. I'm saying it isn't broken. Those aren't the same, and I've been trying for seven weeks to find a way to say the second one without it sounding like the first."

Nakagawa struck the word.

Seven entries, in Egede's hand, and Nakagawa went through them that night at the station with Egede present, because a thing struck without the person who wrote it teaches nobody anything, and struck artefact from each, and fault where it appeared, and had them rewritten to what the imager had recorded and not one thing more. Optical return, third passage mouth, edge lit, no thermal, no sound, no mass. Forty seconds. And the count.

"It's a reading," Nakagawa said, before Egede could. "I know it is. So is broken. I let yours stand for seven weeks because it was the better one, and it was, and it was still a reading, and I let it into the file as a fact, which is the one thing I have told you both for three years not to do. That is my entry, not yours, and it is in the file too."

Egede, to Egede's credit, said nothing for a while, and then said: "What is it, then?"

"I don't know. Neither do you. Neither does Aravena, who has the best account of it and knows it isn't one." Nakagawa turned the screen off. "Here is what I know. A shape with a return on one channel and nothing on any other, at this party's furthest working point, seven times. There is a page in the Corps for that. I have not read it. It is not a planetary survey's page. It belongs to the people who sit at the boundary stations and read this kind of thing for a living, and I know who they are, and I have written to them tonight for one of them, and attached the fact, and attached no reading, and asked them to come and look."

"And until then?"

"Until then the log says what the imager saw. It does not say what the imager saw was. Nobody writes fault and nobody writes anything else. And we knock, and we work, and we do not go down, and we do not put an imager past the junction. Same as always."

Later, in the wind, with the others asleep, Nakagawa sat with it.

Two years the party had kept its back to the dark, and a thing had stood in it for eleven minutes and nobody had looked up. Now the party looked at the dark every evening, on a screen, and had spent seven weeks calling what it saw there a broken instrument. Nakagawa did not think that was worse. It was the same thing from the other side. A survey knows a thing by its warmth first and sees it second, and here was a thing seen first and never warm, and the party had the two words it had always had, somebody and nothing, and this was neither, and so Egede had reached for the only other word there was, and Nakagawa had let the reach stand.

The request was filed. Somebody who knew the page would come, and would read it, and the log would say what they read.

On the third shelf of the rack, under a seal that was not the survey's, something went on logging what the survey had never read.