seawasp | Fenrir: Chapter 20 (Reply)

Stephanie may have the easier job...

Chapter 20: Rescue Options

Time to Launch: 560 days

"Still no sign of activity from Fenrir?" Jeanne asked.

"No, Madame President," York said. "It's still on its hyperbolic course through the inner system. No signals from it that we can detect."

"Do we have any reason to believe there are still 'Fens' to rescue onboard?" Roger asked.

"Some," York said. "Careful analysis of the IR data we're getting indicates that there are still portions of Fenrir that appear to be moderating their temperature – that is, something's keeping them at a relatively constant internal temperature, heating or cooling as needed. The indicated temperature, I'll add, is about twenty-zeven degrees C, a hair over 80 Fahrenheit, which is slightly more than most of us would find comfortable but is a perfectly reasonable temperature for organic beings like us."

He grinned. "And another really, really interesting piece of news is that we've been analyzing the light-curves we get off of Fenrir –"

"Light-curves?" repeated Jeanne. I think I've heard the term, but… "Could you unpack that for me?"

"Of course. Light-curves are the plot of reflected light over time from a target, or a particular part of the target, to put it simply. The important aspect of this is that if a target has physical features on it, and it tilts or rotates or otherwise moves, you can both get an idea of how it's moving, and of details on the surface, by analysis of the curve."

That made perfect sense. "Go on, York."

"Well, as I said, we've been carefully tracking the light-curves from Fenrir, and a large part of it – but not all of it – appears to be rotating." He paused.

Jeanne thought quickly, remembering everything she'd had to cram into her head about spacecraft. "Living quarters?"

"And working areas that need gravity, yes, that's our thought. And it's our first independent confirmation of something else we had just been guessing at before: if our estimates of size are correct, the maximum simulated gravity on Fenrir is just a little bit less than one G."

"Which fit their acceleration profile," Jeanne said, nodding. "So they were maintaining a comfortable acceleration on their way in."

Roger leaned forward, brown eyes wide with interest. "It means more than that, Jeanne. This is strong evidence some of them survived, isn't it?"

York looked mildly surprised; Jeanne had seen this many times before, when Roger stopped being his deliberately background self and showed the intelligence she'd chosen him for. "Exactly right, Roger."

"I'm missing something, so explain why this shows some survived?"

York gestured to Roger, who smiled. "Because they would have been relying on their drive to maintain a sensation of gravity on approach. You see?"

With that hint, she did. "Of course. The Fens had their drive cut off without warning. They wouldn't have needed, or been using, spin-based gravity simulation before the drive cut out. Which means that someone or something onboard had to …" she thought a moment. "Hm. They'd have to reconfigure for 'gravity' along a rotational outward axis instead of along the centerline of the ship, and then start that part rotating."

"Right, Madame President," York confirmed. "Now, a lot of that was almost certainly automated, but I have to assume there would be live participation, or at least oversight, in that complex changeover, so I think it's very strong evidence that we have some number of survivors, and that at least for the first few weeks after the disaster they still had some power and control, even if there was a lot of disruption."

It also implied some much less encouraging facts. "They'd have certainly done everything they could to shift themselves into a decent orbit, yes?"

York's grimace showed she understood the situation well enough. "We all would think so. Which means that, at the least, repairing any major portion of their drive systems was going to be so difficult that they had to prioritize getting their living and working quarters up to gravity first. Or that they had some other problem that absolutely required getting the spinning section moving."

She looked up at the enigmatic shape on her wall screen: the current best-guess as to Fenrir's actual structure, still vague. A long, generally cylindrical form with remnant ruffles of the radiator array towards one end, Fenrir remained more of a mystery than a vessel. Most of the central part of that cylinder is probably rotating. "So we are still on a rescue mission," she said finally. "There could be hundreds of thousands of Fen onboard that ship; there's no way Carpathia could take them off. Do we believe we have any chance of actually saving more than a fraction of them?"

"Two possibilities – well, with a lot of variations – are still likely, Jeanne," York answered. "The first one is that we can establish enough communications with the Fens, and get enough of our own analyses done, to be able to understand what's wrong with the ship and either fix it ourselves, or help them finish fixing it, at least enough to put Fenrir into a decent orbit around the Sun."

"And the second?"

York grinned. "We find the right part of Fenrir to take the strain, lock Carpathia to it, and push it into orbit on our own."

Roger stared at him. "Is that even possible? Fenrir outmasses Carpathia by at least two to three thousand times!"

"We've got people working on it… but the answer's a big, solid maybe. Depends on just how big a bang Carpathia can handle, what stresses Fenrir can take, whether we'll have enough antimatter and uranium and such available… but it's actually not entirely out of the question.

"See, mass difference really isn't the major problem," York went on. "It's easier than being an ocean tugboat – you're not going to be fighting waves, currents, wind, whatever. Experiments like DART showed – as we always thought – relatively small forces can affect the orbits of vastly larger objects.

"The question is the total delta-v, change in velocity, that Carpathia could impart to something like Fenrir. If we were relying on chemical drives, there'd be no way we could; you'd need multiple fuel tanks bigger than the whole of Carpathia to shift it. But the energy density of nuclear reactions is over a million times greater, so we just might be able to pull it off.

"It'd be a hell of a challenge, though, like an ant shoving a pencil and trying to make it go in exactly one direction." He grinned again. "But boy, you'd be really impressed with that ant!"

"I suppose you would," Jeanne said after a moment spent imagining Carpathia pushing the city-sized Fenrir. "But I think we'd much prefer the first option."

"Absolutely," York said, his expression far more serious. "The second option is the 'Hail Mary' at the end. Taken together it would have chances of doing all sorts of terrible things ranging from smashing Carpathia against Fenrir, breaking Fenrir in any of a dozen ways, or even nuking Fenrir by accident."

He shrugged. "And being honest, I'm really not sure you could get enough thrust long enough to make a difference in the orbit. We'd probably have to find a way to dump most of Fenrir to do it, and that'd lose us a lot of the stuff we wanted to study. Of course, the Fens might be able to give us the info we'd lost, but still, it'd be a mess. Just imagine trying to get across to aliens that we're going to cut their ship into pieces so we can save them."

"No, thank you," Roger said firmly. "Are things otherwise going smoothly? We know that Dr. Bronson's still out at the main site."

"Very smoothly," York said, then frowned.

"What is it?" Jeanne asked.

"That's the problem. It's all going smoothly. IIS's inspection signed off on the plate integrity, so the part of Carpathia that has to survive being nuked a few thousand times is done. They've scanned two of the eight main support members for the big shock absorbers and those have passed. They've vetted the top crew and they should be meeting soon to start integrating their operations and understanding of the ship. Civilian crew selection's underway. Designs for the living quarters are almost done." York shrugged.

"Honestly? I'm waiting for the other shoe to drop. Nothing goes this well, not without something going wrong."

Oh, come on, York, what's the chances of an author throwing in more complications just to make the characters have a hard time?