Seveneves - Страница 92

In any event, it had been a dead issue for two years. But that didn’t prevent Mars from showing up in her dreams, and now infiltrating her daydreams. Almost three years had now gone by since she had walked on the surface of a planet, looked up into a sky, seen a horizon. Intellectually she knew that death would take her, sooner or later, before she did any of those things again. She and everyone else in the Cloud Ark would live out their lives in environments resembling bomb shelters, hospital basements, and research labs. The best they could hope for was to look out a small window at the starry sky. The view of the blue, green, and white Earth had once provided fascination and solace. The orange ball of fire they now circled was such a disagreeable sight that most people actively avoided looking at it. No one was ever going back there. For those who still aspired to go for a walk before dying of old age, Mars was the only hope, be it ever so impractical. People had been talking about it on Spacebook, and on some of the blogs that had been cropping up on the Cloud Ark’s miniature Internet. Before the loss of New Caird had severed Ymir’s data link to the Cloud Ark, some of it had trickled through to her tablet, and Dinah read it in idle moments.

At least she had some idle moments now. Since the decision to try the scarfed-nozzle approach, they had executed two burns, about twenty-four hours apart, each with a slightly different configuration of the ice nozzle: a canted lip, constructed by the Nat swarm, projecting almost imperceptibly above the aft surface of the shard and bending the torrent of steam slightly. The first of those burns had gotten them spinning the way they wanted to go, though “spinning” might be too strong a word for a rotation that took the better part of a day. During that day the Nats had decamped to the other side of the nozzle’s rim and built a lip there. The second burn, then, had stopped the rotation that the first one had started, and brought them close enough to their desired attitude that the surviving thrusters could handle the details.

Another perigee was coming up soon. This time the nozzle would be aimed the way they wanted it — forward, once again turning the nuclear engine into a powerful retro-rocket. The robots on the inside of the shard had been at work scooping it out, sculpting the walnut-shell architecture that, according to the structural engineering simulations, would enable the whole thing to hold together during the last round of maneuvers. The hoppers were full of ice, with more on the way, and they’d finally learned how to make the system work consistently. Part of that lesson was not to try to accomplish too much with any one burn. It was better to take it easy, set a reasonable delta vee target, get it done and lock it down, then take stock of the situation and plan the next burn at leisure. Consequently their rendezvous with Izzy looked to be happening much later than they’d first expected, and almost every day brought a further postponement. But at the same time it came to seem more and more of a sure thing, less of a wild chance, and this began to affect Dinah’s thinking. Her robots were doing their work almost entirely on autopilot, leaving her somewhat bored. Vyacheslav, sealed up on the other side of a wall of plastic, could be talked to, but preferred keeping to himself. Jiro, on the other hand, had been working almost around the clock and had been showing signs of strain. Dinah would find excuses to float behind him and look over his shoulder at his screen. Was he playing solitaire? Running orbital mechanics simulations? Writing his memoirs? He seemed mostly to be looking at video feeds of machinery. By process of elimination, this had to be near the core of the reactor.

In the floor of the “bottom”-most level, three stories “below” them, was a manhole giving way to a shaft sunk into the ice. At the far end of that shaft was another hatch providing access to what, on an oceangoing ship of Old Earth, would have been called the boiler room. A small pressurized compartment housed control panels and access ports connected to the reactor, which was only a few meters away, on the other side of a heavy wall. The wall was a radiation shield, at least in theory. But sending up a huge piece of lead hadn’t been an option for the hastily assembled Ymir expedition, and so the “boiler room” got washed with neutrons and gamma rays whenever the reactor was used. The radiation detectors that Sean and company had left behind, the last time they’d closed that hatch, didn’t leave much to the imagination. The place was a hellhole now. Fortunately, all the systems connected there had been designed to be operated remotely, from the safety of the command module, so there was no need to go down that ice tunnel and open that hatch.

Their instruments told them they were nearing perigee again. Jiro, assisted by Dinah, executed what they hoped would be the second-to-last burn of the big engine. This went on longer than Jiro had predicted, but it seemed to work. Ymir shed most of her excess velocity. Her orbit, at apogee, was now only a few hundred kilometers higher than Izzy’s. In spite of attrition suffered by the robots as they wore out, broke, or succumbed to radiation damage, Dinah still had enough of them to restock the hoppers for the final major burn, which they calculated would be happening at a perigee a few hours later.

“If you are satisfied with the disposition of your robots,” Jiro said, “I would like to show you how to operate the main propulsion.”

She had grown up in mining camps where older men liked to amuse her, and themselves, by teaching her how to operate heavy machinery, blow things up with dynamite, pilot airplanes, and the like. So Jiro’s offer didn’t seem unusual to her, at first. Teaching people how to do stuff was, among other things, a way to alleviate boredom. But over the course of the next hour it slowly became clear to her that Jiro really was expecting her to operate the engine during the upcoming burn. It might have been the language barrier; but his English was pretty good, and he was being quite persistent in saying things like “you will keep an eye on this thermocouple” and “you might see some flutter in this valve.”

“If you don’t hear from me beyond the thirty-second mark,” he said at one point, “then you are on your own and you will have to initiate shutdown based on observed delta vee.”

“Why would I not hear from you?” Dinah asked. “Where are you going to be?”

“In the boiler room,” Jiro said.

“Why would you go there?”

“Some of the control blade actuators have stopped responding,” he said. “I think that the electronics have been damaged by radiation. It’s okay. We have replacements. But they will have to be installed manually.”

“So you’re going to go down there?”

“Yes,” Jiro said. “And that is where I am going to stay.”

“IT IS FOR ALL PURPOSES EMPTY,” TEKLA REPORTED OVER AN ENCRYPTED voice link to Ivy. “Empty of people. Empty of supplies.”

She, Tom Van Meter, and Bolor-Erdene had spent the last ten minutes searching Arklet 98 from front door to boiler room, under the eye of Sal Guodian. They had arrived via Flivver, docked, and entered 98 without incident. Sal had gone through first, carrying a tablet on which was displayed the first search warrant ever issued under the provisions of the Cloud Ark Constitution. He had been ready to show it to the first person who challenged him. But no one was here.

Tekla, Tom, and Bo had then come in, wearing orange vests improvised from survival kits that, since they’d been designed for use on Earth, had no practical utility anymore. These would serve as police uniforms until something else could be stitched together. With any luck, they wouldn’t be needing a lot of cop gear. But Ivy had been clear, and the others in her ad hoc council had agreed, that if they were executing what amounted to a police action, they couldn’t beat around the bush — couldn’t try to palm it off as an informal visit. A new constitution had to be exercised, or it was just words.

“Can you get it back on the SAN?” Ivy asked, over the voice link. “I’d like to see what’s happening.”

“I’ll reboot everything,” Sal said, pulling himself up into the control couch. “But it depends on what Spencer did — whether he broke it permanently, or just entered a temporary command.” He reached around in back of a panel, felt for a connector, pulled it out, and jacked it back in.

“We had estimated that you were going to find ten person-years worth of nonrenewables in that thing,” Ivy said. She meant, not bulk food (which could be grown in the outer hull space of an arklet) or air (which was renewed by the life support system), but generally smaller items like toiletries, vitamins, medicine, and specialty food. “That was based on circumstantial evidence — the amount of stuff that’s gone missing, the number of Flivver trips and EVAs that have touched that arklet. We always knew it was only a guess. But for it to contain nothing at all is. . odd.”

“More than odd,” Tekla said. “Surprise attack.”

“You think there’s going to be an attack?”

“Maybe not in sense of violent assault,” Tekla said, “but something.”

“And Arklet 98 was a decoy?”

“Obviously.”

A musical tone sounded from the arklet’s PA speakers, and the white LEDs changed their hue to red. “Alert,” said a synthesized voice. “All personnel should now be awake and at stations for urgent swarm maneuver. This is not a drill.”