Seveneves. Neal Stephenson

two weeks. Its purpose was to serve as a jury-rigged bridge connecting Luk to Orlan.

      The Vestibyul was barely large enough to accommodate a supine human. At one end was a flange that mated with the forty-centimeter ring on a Luk. Having slithered feetfirst from the Luk into the Vestibyul, a cosmonaut had just enough wiggle room to get his feet aimed down the legs of the Orlan suit that was attached to the other end, its door hanging open. Before doing this, however, he would seal off the Luk by manually putting its diaphragm into position and bolting it into place with a ratchet wrench.

      Having donned the Orlan, he could then activate a mechanism, built into the Vestibyul, that would close the suit’s door behind him. The small amount of residual air in the Vestibyul would hiss out into space and the cosmonaut would be free to depart. At the end of the workday, the whole procedure was reversed. Just like a suburban commuter sleeping in a split-level home with his car parked in the garage, the cosmonaut would enjoy a few hours of rest and relaxation floating around the confines of the Luk with his space suit docked at the end of the adjoining Vestibyul.

      There were a number of catches.

       Luk, Vestibyul, and suit formed a closed system. The only way to escape from that system was to successfully don the suit, get the door closed, and spacewalk to an airlock. If anything went wrong that prevented donning the suit and closing the door, rescue was impossible, or at least spectacularly improbable. A perforated Luk, probably caused by a micrometeoroid, caused a fatality on the second day of the Scout program. After that, the Luk/Vestibyul systems were brought forward to huddle in the shelter of Amalthea. The asteroid wouldn’t stop all incoming rocks, but it would stop many.

       Since there was no practical way in or out of the system, the Scouts had to fly up from Baikonur in their space suits, preattached to their Vestibyuls and Luks. This was necessitated anyway by the fact that none of this equipment could be accommodated inside of a normal space capsule. So they had to fly up crammed, six at a time, into cargo carriers that were not rated for human use and that had no onboard life support. They were, therefore, living off their space suits’ internal supplies of air and power from shortly before launch until their arrival at ISS. This journey could not be accomplished in less than six hours and so supplemental air and power had to be delivered to the suits en route. The failure of systems responsible for doing that accounted for two fatalities in the first crew of six Scouts and one fatality in the second crew.

       The capabilities of the suits were being wildly overstretched by these new mission parameters, and of course the Luks didn’t really have significant life support systems of their own, so everything depended on umbilical lines that linked these contraptions to Zavod modules. Zavod was simply the Russian word for “factory.” This was another new device that had been cobbled together in two weeks from existing technology. As long as the Zavod was supplied with power, water, and a few consumables, it was supposed to keep a cosmonaut alive by scrubbing CO2 out of the air, collecting urine, and removing their body heat. The heat was gotten rid of by freezing water on a surface exposed to the vacuum and then letting it sublimate into space. Failures of Zavod modules accounted for four fatalities among the first three crews sent up. Two of these were caused by a bug in the software, subsequently fixed by a patch transmitted up from the ground. One was a leaky hose. The other was never explained, but the fatality was witnessed by Izzy’s crew, watching through windows and video feeds, and seemed to match the profile for hyperthermia. The cooling system had failed and the cosmonaut had lost consciousness and succumbed to heatstroke. After that, they had stopped using the jerry-built cooling systems that had shipped up with the Luks and simply used ziplock bags full of ice, delivered daily.

      None of this even accounted for mishaps that occurred while the Scouts were actually working. A damaged umbilical nearly killed a Scout on A+0.35, and he was obliged to disconnect himself from his Zavod and execute a heroic and perilous move to the nearest airlock, where they got him inside the space station with less than a minute to spare.

      Two days later a Scout simply disappeared without explanation, possibly the victim of a micrometeoroid, or even of suicide.

      So, of the first crew of six Scouts, two were dead on arrival and one was killed in the Luk failure the next day. Of the second crew, one was dead on arrival. All six of the third crew made it to Izzy alive. Of the fourteen total survivors, four died from Zavod failures, one disappeared, and one was forced to “retire” from being a Scout and confine his activities to Izzy because of equipment failure.

      Ivy, being at the top of the org chart, was responsible for all strange and extraordinary decisions: the problems that no one else knew how, or was willing, to handle. It became her problem to decide what they were going to do with dead people.

      Oh, there was a procedure. NASA had a procedure for everything. They had long ago anticipated that an astronaut might die of a heart attack or some mishap during a mission. Since two hundred pounds of rotting flesh could not be accommodated inside of the space station where people lived and worked, the general idea was to let them freeze-dry in space, and then place them aboard the next earthbound Soyuz capsule. Only the middle section of the Soyuz, the reentry module, ever made it back to Earth. The spheroidal orbital module, perched on top of it, was jettisoned before reentry. Eventually it burned up in the Earth’s atmosphere. The customary procedure, therefore, was to pack the orbital module with trash so that it would be burned up as well.

      Bodies were not trash, of course, but burning them up in the atmosphere seemed as good a way as any to dispose of them—the space-age equivalent of a Viking funeral.

      The normal up/down cycle of launch and reentry had, of course, been suspended. Things were supposed to go up, but not come down. Those orbital modules could be preserved and used as habitats, or for storing supplies. The “trash” could be picked over and used again. Bags of fecal material could become fertilizer in hydroponic farms.

      Ivy made a unilateral decision that they would carve out an exception to that new policy. The deceased were moved into an empty orbital module docked at the truss. This was left open to space, so that freeze-drying of the bodies could happen out of sight and out of mind. When it filled up with dead people, they would have some kind of ceremony, the thing would be deorbited, and they would watch in silence as it drew a white-hot streak across the atmosphere below.

      But it wasn’t full quite yet.

      They had eight working Scouts until such time as another heavy-lift rocket could be prepared and sent up with a fresh half dozen. These worked in fifteen-, sometimes eighteen-hour shifts divided into three-hour phases. Each of those phases consisted of two hours’ actual work followed by an hour of resting in situ, or, using the obvious anagram, in suit.

      Dinah, working in her robot shop, didn’t have a direct view of what they were doing, since her window faced away from the truss where they spent all of their time. She could watch their activities on video feeds if she wanted, but she had other things she needed to be doing.

      After the micrometeoroid/Luk incident, Dinah had scored a small victory for robotdom by putting her flock to work getting the surviving Luks squared away. Amalthea was attached to the forward end of Izzy, which, because of its orbital direction, was most exposed to impacts from space junk. In effect the asteroid had been put there as a sort of battering ram, protecting everything aft of it from collisions. There was enough space on its aft side that several Luks could nestle there, improving their odds of long-term survival as well as cutting down on cosmic ray exposure.

      Dinah’s crew of iron-mining robots had been made obsolete, at least for the time being, by her boss’s pivot toward frozen water. So, when not making tiny critters scurry around on slabs of contraband ice, she had made the older robots useful by getting them to drill holes and anchor some connection points—eye bolts, basically—into Amalthea’s back side and then moor the Luks to them using cables. This was not a hard-and-fast mooring system, so at first they tended to drift around and lazily bump into each other like a string of balloons. But after a day or two they settled into a stable configuration that just happened to block Dinah’s view out her window. All she could see now was plastic. She didn’t mind. After seeing the risks that the Scouts were taking, she didn’t mind anything at all.

      Individual