Izzy, which had been a complicated and hard-to-understand contraption even before all of this had happened, was now an utterly bewildering maze of modules, hamster tubes, trusses, and ships docked to ships docked to ships, “like a freakin’ three-dimensional domino game,” as Luisa put it. The only way to get one’s bearings, looking at a rendering of the complex, was by picking out the rugged and asymmetrical shape of Amalthea at one end and the two tori at the other. Those were “forward” and “aft,” respectively, and the axis between them was the basis for the traditional nautical directions of “port” and “starboard” as well as “zenith” and “nadir,” which were space lingo for basically “up away from Earth” and “down toward Earth.” If you arranged yourself so that your back was to the tori and your face toward Amalthea, with the “port” stuff on your left hand and the “starboard” stuff on your right, then your head would be aimed toward the zenith and your feet toward the nadir and the surface of Earth four hundred kilometers below.
That, however, was the privileged view of people outside the thing in space suits. Inside, it was still easy to get lost in the three-dimensional domino game. Felt-tip markers, always a scarce resource even on Earth, became objects of great value as people used them to mark directions on the walls of hamster tubes and habitat modules.
“IT’S JUST A CHRONOLOGICAL ACCIDENT THAT I’M HERE AT ALL,” IVY mused, during one of her and Dinah’s increasingly rare drinking sessions. All of their original stashes of booze had long since been consumed, but new arrivals were kind enough to slip them bottles from time to time.
“I disagree,” Dinah said. It wasn’t exactly a scintillating response. But she’d been caught off guard by the suddenness with which Ivy had dropped her guard.
“If the moon had blown up two weeks later, some Russian sourpuss would be in charge up here and I’d be on the ground, married and pregnant.”
“And under the same death sentence as everyone else.”
“Yeah, well, there’s that.”
Dinah reached for the bottle and refilled the shot glasses, trying to stretch out the moment. It had never been easy to get Ivy to open up, even back in the happy days before Zero.
“Look, Ivy, it’s not an accident that you were in charge of Izzy. They gave you the job for a reason. You’re the last girl in the world—or out of it—who should be suffering from impostor syndrome.”
Ivy stared at her through a somewhat amused silence. “Go on,” she finally said. “What is this impostor syndrome you speak of?” For they’d talked about it before—but usually with Dinah being the one who felt it.
“Don’t try to deflect this. What’s going on?”
Ivy glanced at the ceiling: a sort of visual signal, borrowed from the Russians, to remind Dinah that you never knew when someone was listening. Then she looked into Dinah’s eyes. But only for a moment. She was fundamentally a shy person, who preferred inspecting her shoes while baring her soul.
“You and Sean Probst made great sparring partners,” Ivy said.
“He was so fucking obnoxious! He needed someone to—” Dinah cut herself short then, because Ivy had gotten a sort of sad, wry look on her face and held up one hand to stop her.
“Agreed! Yes. Thanks for doing it,” Ivy said. “He needed someone like you around. Sometimes it almost looked like a comedy act between you two. And the way that the Russians reacted to him—Tekla first of all, of course, but later Fyodor proposing to place all Arjuna personnel under arrest and confiscate everything they’d brought up with them—that was great drama. Tabloid stories and comment threads galore down on the surface. But I barely survived it.”
“What do you mean, you barely survived?”
“You wouldn’t believe some of the conferences I had with Baikonur and Houston. People down there wanted me to take a very hard line. To do what Fyodor wanted.”
“But you didn’t,” Dinah pointed out.
Ivy met her gaze again. Then, after a moment, she gave a little nod.
“So you won,” Dinah went on.
“I won a Pyrrhic victory,” Ivy said. “I negotiated a less draconian solution. The Ymir expedition went on its way with no obvious hard feelings.”
“And how is that Pyrrhic?”
“I don’t want to make my problems yours,” Ivy said.
“Who else are you going to talk to?”
“Maybe no one,” Ivy returned, showing a flash of something like anger. “Maybe that’s what a leader is, Dinah. The one person who can’t—who shouldn’t—share her problems with anyone else. It’s sort of an old-fashioned idea. But the human race might need such people going forward.”
Dinah just stared back at her. Finally, Ivy relented, and spoke in tones almost devoid of feeling: “My position as the head of the space station came under serious challenge. It made me aware of politics on the ground that have been going on for some time—but that were invisible to me until the Sean Probst controversy surfaced them. Since then, I believe that my authority has been further undermined by people on the ground, leaking things to the press, saying things in meetings.”
“Pete Starling.”
“No comment. Anyway, I think I am going to be replaced before long.”
Ivy’s eyes had reddened slightly. She made another glance at the ceiling, but the expression on her face suggested she didn’t care who might have heard her. Then she looked at Dinah and smiled. “How have you been doing, sister?” she asked in a weak voice.
“I’ve been pretty good,” Dinah said.
“Really? That’s music to my ears.”
“Bo, Larz, the others who’ve come up to work in my crew, they seem to respect what I’ve done,” Dinah said.
“I think it’s because of what you did for Tekla,” Ivy said.
“Oh really? Not just my amazing natural competence?”
“There are a lot of people on the ground who are competent in the way you mean,” Ivy said, “and we are going to be seeing a lot of them up here in the next few weeks. Believe me. I’ve read their CVs.”
“I’m sure you have.”
“But everyone kinda senses now that some other qualities are going to be needed besides just pure competence. That’s why people are deferring to you.”
Another awkward silence. Ivy seemed to be suggesting that she, Ivy, was no longer being given that kind of respect.
“That, and your amazing competence,” Ivy added.
Consolidation
EARTH’S ATMOSPHERE DIDN’T JUST STOP. IT PETERED OUT UNTIL IT became indistinguishable, by most measuring devices, from a perfect vacuum. Below about 160 kilometers of altitude, the air was still thick enough to rapidly drag down anything placed in orbit, so those altitudes were used only for short-term satellites like the early space capsules. The higher the altitude, the thinner the air and the more slowly orbits decayed.
Izzy was four hundred kilometers up. Its acres of solar panels and radiators made it extremely draggy in comparison to its mass. Or at least that had been the case until Amalthea had been bolted onto it, suddenly making it far heavier.
Somewhat paradoxically to laypersons, the added mass of the asteroid made Izzy much better at staying aloft. Before Amalthea, the station had lost two kilometers of altitude every month, making it necessary to reboost it by firing a rocket engine on its aft end. In the early days, that engine had been the built-in one mounted on the Zvezda module. But in general they simply used the engine belonging to whatever spacecraft happened to be docked to Izzy’s aft-most module.
In those days Izzy had been like a kite: all surface area, no mass. In technical terms, it had had a low ballistic coefficient: a way of saying that it was strongly affected by what little atmosphere there was. Once Amalthea had been attached, it was like a kite with a big rock strapped to it. It had a high ballistic coefficient. The rock’s momentum bulled through the evanescent atmosphere and led to much slower orbital decay. But by the same token, when it came time to reboost Izzy’s orbit, a longer burn and a
larger amount of propellant were needed in order to accelerate all of that iron and nickel.
Since the Scouts and the Pioneers had begun adding more bits onto Izzy, its ballistic coefficient had been dropping again, and boost burns had come more frequently. And it was always the case that thrusters had to be fired every now and again to correct the station’s altitude. All of it grew more problematic as more was added onto the basic structure. Izzy had been an ungainly construct even before all the new pieces had been added onto it. Thrust applied to one part of it would ramify through the other modules as various parts of the truss and other structural members took up the strain and passed it on down the line. To put it in the simplest possible terms, Izzy had gotten all floppy as more stuff was attached to it, and its floppiness made it difficult to reboost the orbit or even to tweak the angle at which it “flew” through space. They had allowed the orbit to decay by a serious amount, over sixteen kilometers, during the busiest part of the Pioneers’ efforts, but now reboosting had to become a routine operation. And every firing of the engine on the bottom of H2 revealed structural weaknesses that had to be jury-rigged, sometimes literally with zip ties and duct tape, before it could proceed.
During the span of time from about A+0.144 to 250, the watchword was “consolidation,” inevitably trimmed to “consol.” It basically meant the retrofitting of new trusswork around the hamster tubes and other sprawling constructs that had been added to the truss during the frantic first couple of months. Other problems were addressed at the same time, most notably the building of more radiators for dumping waste heat into space. These didn’t work if they were too closely spaced—they just shone heat on one another. So the heat rejection complex waxed enormous and ended up growing generally aftward, like an empennage—the feathers on the butt of an arrow. It was no mere figure of speech. In the same way that an arrow’s heavy head and spreading feathers kept it pointed straight forward, the combination of massive Amalthea at the forward end and the heat radiators trailing away aft helped keep Izzy pointed in the right direction and somewhat reduced the demand for thruster firings. It also protected the radiators from micrometeoroids. Rocks could theoretically come from any direction and strike the space station, but they were most likely to hit its forward end, and so forward-facing surfaces of the space station’s modules had generally been equipped with shields. Amalthea, of course, was the biggest and best shield of all.
The number of solar panels might have grown too, had they been doing things the old way. But very early in the Cloud Ark project it had become obvious that, while photovoltaics might be a useful adjunct, the only sure way to keep everything running was with the small nuclear devices called RTGs, or radioisotope thermoelectric generators. These made heat all the time, whether you wanted them to or not, and so created further demand for radiators.
The radiators were, in essence, a gigantic exploit in zero-gravity plumbing. The excess heat had to be collected from where it was produced (mostly, the inhabited and pressurized parts of Izzy) and transported to where it could be gotten rid of (the “empennage” growing to aft). The only plausible way of doing this was by using a fluid, pumping it around a loop, heating it up at one end and cooling it off at the other. At the hot end they used heat exchangers and so-called cold plates that just soaked up heat from wherever it was a problem. At the cold end the fluid fanned out through networks of thin tubes, like capillaries, sandwiched between flat panels whose sole purpose was to become slightly warm and shine infrared light into deep space, cooling down Izzy by warming up faraway galaxies. Joining the hot and cold ends of the loop was a system of pumps and pipes that got bigger every day and that was prone to many of the same kinds of trouble as bedeviled earthbound plumbing. Making it twice as complicated was that some of the loops used anhydrous ammonia and others used water. Ammonia worked better, but it was dangerous, and you couldn’t easily get more of it in space. If the Cloud Ark survived, it would survive on a water-based economy. A hundred years from now everything in space would be cooled by circulating water systems. But for now they had to keep the ammonia-based equipment running as well.
Further complications, as if any were wanted, came from the fact that the systems had to be fault tolerant. If one of them got bashed by a hurtling piece of moon shrapnel and began to leak, it needed to be isolated from the rest of the system before too much of the precious water, or ammonia, leaked into space. So, the system as a whole possessed vast hierarchies of check valves, crossover switches, and redundancies that had saturated even Ivy’s brain, normally an infinite sink for detail. She’d had to delegate all cooling-related matters to a working group that was about three-quarters Russian and one-quarter American. The majority of all space walk activity was related to the expansion and maintenance of the cooling system and, uncharacteristically for her, she was content just to get a report on it once a day.
All of that plumbing, and all of those radiators, needed to be supported by Izzy’s structure just like anything else—they were especially prone to troubles under the general heading of “too floppy to survive reboost.” So, proceeding in the same general putting-out-fires mode, Ivy and the engineers on the ground next had to steer the program in the general direction of “consol,” or, as Ivy put it privately, “defloppification,” of the space station’s overall structure. And since it was out of the question to take apart what the Scouts and Pioneers had put in place, this took the form of building what amounted to external scaffolding around what was there. Viewed from a kilometer away, it looked quite similar to what one saw when some old and treasured building was being renovated: a latticework of structure, ugly but serviceable, grew around the underlying object, enveloping it and strengthening it without actually penetrating it.
In the early going, sections of truss were assembled on the ground, launched up whole, and slammed into place by teams of spacewalkers, buying large increases in structural integrity quickly and expensively. That approach soon fell prey to the law of diminishing returns and it became clear that the Arkers, as they’d started to be known, couldn’t be forever dependent on ground-based engineers custom-building structures.
The ground-based engineers didn’t even really know what was going on with Izzy anymore. Their CAD models had fallen behind. Dinah knew it because of a sudden surge in messages from exasperated engineers requesting that she send a robot out to such-and-such a place and aim its camera at such-and-such a module so that they could see what was actually there.
The Arkers needed tools and materials for building their own structures in situ. These started to arrive around Day 220. And it was a measure of how much things had changed on the ground that the solutions came in more than one form, from more than one source, often with little to no coordination. In the old days a proposed system would have been given a three-letter acronym and bounced back and forth between different agencies and contractors for fifteen years before being launched into space.
The single most useful structure-building system turned out to be a rough-and-ready implementation of an old but good idea. It was a little bit like the machine used by gutter and downspout contractors, mounted in the back of a truck, fed by a large roll of sheet metal, which would be bent into a gutter shape and extruded in pieces as long as you liked. This machine did much the same thing, except that it bent the sheet metal ribbon into a simple beam with a triangular cross section and then welded the edges together to make it permanent. It had been invented and prototyped long ago in the West, but the Chinese space agency had perfected it in the first couple of hundred days post-Zero and begun to launch the machines up with crews who knew how to use them. As long as they were supplied with electricity and rolls of aluminum they would go on pumping out beams forever. Connecting segments of beam into more complex structures, such as trusses and scaffolding, was a little more difficult. Welding in space, while possible, was complicated, and there wasn’t enough equipment. Instead they ended up using Tinkertoy-like connectors, again mass-produced by the Chin
ese, into which the ends of the triangular beams could be inserted, then tightened down using screws. At first many of these were shipped up in bulk from the ground, but on A+0.247 they took delivery of a 3-D printer that had been optimized to make more of them, with options for modifying the angle at which the beams would be inserted. This gave them the ability to design and build trusses on the fly, which was not possible with the mass-produced connectors. And as a last resort, Fyodor had an electron-beam welding machine that would work in zero gravity and a vacuum, undoubtedly the most expensive welder ever made, a marvel of Russian ingenuity, and he had trained Vyacheslav to use it. Vyacheslav then trained Tekla and two of the other spacewalkers, who set up a job queue and took turns drifting around Izzy’s increasingly complex structure tacking down a weld here and a weld there. Thus, constructed largely by the Chinese and the Russians, the scaffolding grew and stiffened. The reboost burns no longer produced alarming pops, bangs, and groaning noises. The hamster tubes gradually disappeared within shrouds of structural reinforcement and shielding. New docking ports began to sprout at Izzy’s extremities, like buds on tree branches, in preparation for the next phase: the coming of the first arklets.
Down on the Earth, it was August, the second-to-the-last August that there would ever be. A dozen new or reconditioned spaceports had come into operation. Heavy-lift rockets could now be launched to Izzy from eight different locations around the world. Around those launch pads, rocket stages and three different styles of arklet were beginning to pile up like so much ammunition at a firing range.
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