The second complication was the ship’s slow tumble. This meant that their nuclear rocket engine was never pointed in the right direction, save by lucky accident. During the big burn at perigee, they had wanted the nozzle pointed forward, so that it would serve as a huge retro-rocket. The upcoming burn at apogee was intended to speed her up a bit, and so they needed the nozzle pointed aft. But as long as she tumbled, it was aimed in no particular direction.
So their task now was to stabilize Ymir’s attitude by using her thrusters to push back against the unwanted rotation. And, as they had discovered the first time they’d tried it, her thrusters were small and weak compared to the momentum of the big ice shard. In aerospace lingo, they lacked control authority. Ymir was like a truck skidding on a patch of oil, responding only faintly to the steering wheel. That problem had been alleviated somewhat by the large expenditure of mass during the burn. Many tons of ice had been hurled out the nozzle in the form of steam. Ymir was lighter and more wieldy as a result. Calculating exactly how much more wieldy she was, and what it meant for the thrusters’ control authority, was, in itself, a significant task that consumed another half an hour just for a rough estimate.
The result was not encouraging. In the three hours remaining, there was simply no way that Ymir’s attitude control thrusters—designed for tiny adjustments over long spans of time—could neutralize her tumble. The tumble wasn’t especially fast—the crew in the command module could barely sense that they were rotating—but it was enough to make the next rocket burn impossible. And if they couldn’t make that burn in three hours, they’d scrape the atmosphere again in an additional four, and again eight hours after that. They might survive one more ride like the first one, but they couldn’t survive two.
Once all of this had become clear to Markus, he had divided the crew in half, leaving Dinah and Jiro in the command module’s common room to look after the propulsion system and going “above” with Vyacheslav to consider the problem of attitude control.
Dinah’s task was, comparatively speaking, routine. During the perigee burn, they had expended most of the ice stored in the hoppers. Some of the augers had jammed, and the whole ice-mining operation had been thrown into general disarray as she had improvised solutions to problems that came at her from every direction. Robots were in the wrong places; some hoppers were overfull while others were empty. New ice needed to be mined and old ice needed to be rearranged. Fixing all of that in time for another burn in three hours was not an insuperable task, but it would require her full attention. Likewise, Jiro had a few reactor issues to think about. Both of them would have to toil diligently between now and the apogee burn in order to be ready.
Assuming, that is, that the other half of the crew had, in the meantime, figured out a way to get Ymir aimed in the right direction. Markus had moved that job to another part of the ship where it wouldn’t pose a distraction to the propulsion crew. Or such was his intent; but in moments when Dinah lost focus briefly, while compiling some code or foraging for a snack, she found herself wondering what they were doing up there.
By process of elimination, it had to be something involving New Caird. They had already demonstrated that Ymir’s thrusters weren’t up to the task. Only New Caird’s main engine had enough thrust to make a difference. The problem was that it was pointed in one fixed direction, which didn’t happen to be the one in which they actually needed to push.
Following that chain of reasoning to its logical conclusion made her nervous, to the point where she was almost more distracted than she would have been had Markus and Slava been working in the same room with her.
She held her curiosity and her trepidation at bay until she was certain that the engine would have enough ice to achieve the apogee burn. Her work was finished. Half an hour remained. Jiro seemed to have his side of it under control.
A sharp thud, resounding through the walls of the command module, gave her an excuse to pull up some video and to eavesdrop on the audio channel that Markus and Slava were using. Robots salted all over Ymir’s exterior gave her eyes that she could turn in any direction. Even so, it took her a few minutes to obtain a picture of what was going on.
New Caird had undocked from Ymir and was nowhere to be seen. Presumably Markus was at her controls.
A man in a space suit was visible on the outside of Ymir, “walking” toward the stern by using a pair of Grabbs as mobile anchor points. This had to be Vyacheslav. His feet had sprouted thick white whiskers. It took Dinah a few moments to make sense of the image: he had zip-tied each foot to the back of a Grabb, and the “whiskers” were the protruding ends of the zip ties. It was the kind of improvisation that would have made old-school NASA engineers turn over in their graves, had the Hard Rain not eliminated that possibility. But in the last two years, and particularly the last two weeks, this kind of hillbilly engineering had become routine.
Which only made the question of what the hell Markus was up to more compelling. If Slava was being that creative with two robots and a sack of zip ties . . .
She finally spotted New Caird on a camera belonging to a Bucky that was attached to the stern of the shard, about halfway between its edge and the cavernous maw of the nozzle. The little ship was hanging in space maybe a hundred meters away, white jets erupting from her attitude thrusters every few moments as she tried to keep station behind the slowly rotating shard. Markus was flying her by hand, and it was some fancy flying indeed.
The geometry was difficult to visualize, but Dinah convinced herself that Vyacheslav was “walking” toward the same general location that New Caird was aimed at. In their own ways, the two men were focused on the same part of the shard: one of its outermost corners, where the widest part of the sugarloaf terminated and connected to its base, along a sharp but irregular edge. There, embedded in the ice, was a scrap of structural framework about the size of a car. It served as the anchor for a cluster of small conical rocket nozzles: one of those thruster systems that had proven so miserably underpowered for the current job. Aiming another camera at it, Dinah saw a steady jet of blue-white fire emerging from two of the nozzles. They were burning continuously, full blast. They weren’t designed to do that. But Ymir’s attitude control system had calculated that thrust, and a lot of it needed to be applied in those two directions if its programmed objective—getting the ship’s “nose” pointed forward and her nozzle aft—were to be achieved.
Dinah got it. Her thinking was confirmed by the chatter she could now hear, in a mix of English, German, and Russian, between Markus and Vyacheslav. But she could see in her mind’s eye what Ymir must look like, right now, to Markus, viewing it through the front window of New Caird: a huge drifting arrowhead of black ice, generally dark, but decorated at the nose and “corners” by twinkling white lights, and streaks of hot gas: the exhaust from the thrusters, running an automatic program controlled from within. Sometimes they flashed on and off. Occasionally, though, when a lot of thrust was called for in one place, they ran for a long time. Those long steady burns would stand out clearly against the dark of space.
Markus didn’t need to calculate Ymir’s rotation in his head. He didn’t need to know her spin rates about her three axes or the torque needed to counteract them. He didn’t even need to pull up the user interface on his tablet. All he had to do was fly around the shard and look for places where thrusters were staying on continuously. Those were the ones that were overloaded and underpowered. Those were, therefore, the ones where New Caird’s big engine could be used most effectively.
But how?
Her view of the thruster system was interrupted by a blurry gray form: Vyacheslav moving in front of the camera. He then came back into focus, groping for a carabiner along his waist and snapping it onto a structural member that protruded from the ice. Dinah could hear him breathing. Bracing himself with his left hand, he reached into the network of struts with his right. After a bit of groping he seemed to find something, then worked for a minute, his arm reciprocating sligh
tly.
The thruster jets faltered and winked out.
“Done,” Vyacheslav said. “Apologies. Valve was sticking.”
“Get clear, tovarishch,” Markus said.
“Getting,” Slava returned. He unhooked the carabiner and bent away from the framework, trusting himself to the Grabbs zip-tied to his feet, and began to move away with the painfully slow gait of a man walking in hot caramel. “Just do it,” he said, then added a phrase in German that Dinah was pretty sure meant If it doesn’t work we are all dead anyway.
New Caird drifted out of frame. Dinah spent a few moments reacquiring her view. The smaller ship was closing on Ymir, headed directly for the thruster system that Slava had just shut down, and coming in on an angle between the two nozzles that had been burning.
The logic was clear; the method was insane. New Caird was going to do the job that the tiny thrusters couldn’t. Markus had to get her big nozzle aimed in about the right direction, namely, about halfway between the two that had been doing all the work. Fine. But he was also going to have to make a mechanical connection between New Caird and the shard, so that the thrust of the big engine could be transmitted into the mass of ice.
And it looked like he was going to achieve this by ramming the little ship into the big one. It was a slow ramming, like a tugboat shoving its nose against the side of an oil tanker to nudge it into a berth. But it was ramming nonetheless: not a thing for which spacecraft were generally designed.
She relaxed her painfully tight grip on the edge of the table just a bit when, moments before the collision, Markus fired the retro-thrusters, slowing New Caird at the moment of impact. But still she felt and heard the crunch resounding through the walls of the ice palace. She’d heard it before over the last couple of hours and wondered what it was; apparently Markus had done this several times already.
He had aimed for the place where the structural framework emerged from the ice, forming a sort of angle into which New Caird’s nose could trap itself, as long as the thrust stayed on. Right now that force was being delivered by her aft thrusters. But Dinah, watching Markus’s face through the front window, saw him working at the touch screen that served as New Caird’s control panel, and had a pretty good idea of what was coming next.
She pulled up the interface for Ymir’s attitude control system and saw craziness: thrusters firing all over the shard, lit up by angry icons warning of too little propellant, not enough time, overheated nozzles. The thing that Markus had just rammed was flashing red, indicating that it wasn’t even connected to the system anymore. Graphs at the bottom of the screen, and a three-dimensional rendering of the shard in space, showed just how far off they were from where they wanted to be.
She heard a little symphony of grinding, groaning, and popping, and felt the ship rotating around her.
The video feed showing New Caird was awash in white light as her main propulsion came on full blast. A quick glance at the attitude control plots showed good things happening.
“It is good,” Jiro said, “but we are going to over-rotate now.”
“Not if I got the timing right,” Markus said. “We should rotate through the correct attitude just at the time of the apogee burn. Afterward, yes, we’ll over-rotate. But we’ll have plenty of time to fix it.”
Then his transmission was cut off by an exclamation and a thud. He cursed in German, and then the audio went dead.
Dinah looked at the video feed to see New Caird canted over at the wrong angle. The flame from the engine flickered out.
The framework against which New Caird had been pushing had given way under the thrust of the big engine and crumpled, causing her to slew around. She now lay almost sideways against the ice, the crushed remains of the thruster system sandwiched between her hull and the stern of Ymir.
“Some kind of gas escaping,” Jiro observed quietly. “Or smoke.”
He was right. The eye didn’t pick it up right away because smoke behaved differently in space than in an atmosphere, under gravity. But something was burning, or at least smoldering, along the side of New Caird’s hull, no more than an arm’s length from where Markus sat.
Vyacheslav said, “The hot nozzle of the thruster is melting through the hull.”
Markus came back on the air. “Jiro and Dinah, you must be ready to fire the main propulsion at apogee—” The word was cut off by a constriction of his throat, and he coughed several times. When he resumed speaking, his voice had a strangled timbre. “About two minutes from now. Focus on that—initiate the startup procedures. Vyacheslav can help me with this little problem.” He was coughing convulsively. “Switching off,” he said.
Dinah, against orders, made a last glance at the video feed showing the nose of New Caird. Through its front window she could no longer see Markus. She could see only smoke, and the flickering, lambent light of a fire within it.
The realization of what was happening struck her like a two-by-four across the forehead. She grabbed the edge of the table and closed her eyes for a few moments, felt them fill with hot water, felt the snot flooding into her nose.
“Dinah,” Jiro said. “The auger startup checklist begins now.”
She opened her eyes and saw glowing blurs where user interface widgets ought to have been.
“If it is to mean anything,” Jiro said. “Please.” Then he reached up to enclose his headset’s little microphone with one hand, muffling the sound, and added: “He can probably hear us.”
She reached out and typed a command. “Auger one,” she said. “Go.” And she slapped the Enter key.
And so on down the list. It got easier as she went. Jiro did his part of it delicately, quietly, efficiently. And when the nuke came on to full power, right on schedule, she made sure to mention it. Loudly. In case Markus could hear them.
Only then did she look at the video feed. She was expecting to see Markus’s final resting place, a tomb of acrid smoke.
But nothing was there except a crumpled framework and Vyacheslav, standing with one hand braced against it, gazing away aft. In the background, a spreading plume of steam the size of Manhattan as Jiro’s engine fired.
“Slava?” she said. “Where is—”
“She fell off,” Vyacheslav answered. “When the engine came on, and we began to accelerate. New Caird did not come along for the ride.”
“Is she—”
“She was entrained in the plume of steam and thrown back. I can hardly even see her now.”
“Oh.”
“Dinah?”
“Yes, Slava?”
“Markus was already dead.”
“IT WOULD READ ALMOST AS SLAPSTICK COMEDY IF IT WERE NOT SO tragic—the consequences so dire,” Julia said. She was mesmerized by a video loop, the final transmission from New Caird before radio contact had been lost.
The people hovering around her in the White Arklet—as Julia’s unofficial base of operations had come to be known—all nodded, or made agreeable-sounding murmurs. They were all reading Tav’s blog post about the Ymir catastrophe, which had been posted only seconds ago.
The one exception was Tekla, who had become distracted by a detail. Attached to the wall of the arklet with strips of blue masking tape was a sheet of paper on which had been printed the seal of the president of the United States. Only two printers remained in existence, and both of them were on Izzy. So, by process of elimination, this must have been printed on Old Earth, prior to the Hard Rain, by a device that had been running a little low on cyan ink. It had seen hard service: it was torn in two places and repaired with clear tape. It had been creased and crumpled, then smoothed out. Its edges were fuzzy where previous applications of tape had been peeled away. And in the white space below and to the right of the presidential seal there was a brown smudge, oval, the size of the ball of a person’s thumb. As a matter of fact, Tekla was certain that it was actually a thumbprint, and the more she looked at it the more certain she became that the brown substance was blood.
She looked Juli
a in the eye, and became aware that the former president was awaiting some form of reaction from her. Unlike most people, Tekla felt no pressure, no obligation to fulfill any such expectations. Julia, a bit unnerved by that, broke eye contact and continued: “I don’t quite understand the story they are telling us anyway!”
“It is pretty convoluted,” said one of her aides, a young male Arkie with an American accent. He was one of the MIV engineers. His tone suggested that he was amused by the sheer cheekiness of the powers that be in trying to get people to believe such a yarn, and that he was much too clever to be taken in. “It kind of hinges on the idea that the hull was made out of what amounts to plastic. If it gets too hot, it—”
“It’s like plastic on a stove burner, I understand that,” Julia said. “It melts and it stinks.”
“New Caird shifted in a way that caused the hull to come into contact with a nozzle that was extremely hot.”
“But according to the story they are putting out, Vyacheslav had shut that nozzle off beforehand.”
“They stay hot for a long time. Anyway, the nozzle melted right through the hull. First it would have made a lot of toxic smoke. That would have been enough to kill him. Then, when the melting proceeded to the point where the hull was perforated, all the air would have escaped through the hole.”
“Well, that is horrible—if it is true,” Julia said, and then swiveled her eyes toward Tekla, looking for some sign in the visitor’s face that it might not be true. Tekla stared back at her in a manner that betrayed nothing. “What sort of pass have we come to, one wonders, when such crazy improvisations are called for—ramming one ship with another!”
More murmurs of agreement.
Julia was on a roll. “And as far as I can make out, it didn’t even solve the problem!”
“Problem is solved,” Tekla said. She was fluent in English and was perfectly capable of saying “The problem is solved,” but sometimes dropped the article for effect. Anglophones found this mysterious and impressive. It was also an implicit statement of Russian pride. The language of the Cloud Ark, by default, was English. That was never going to change. But the dialect was going to evolve over time, and Russians could bend it in their direction by finding ways to inject their grammar and vocabulary into everyday speech. “Burn is complete,” she went on.
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