Greg Egan - The Clockwork Rocket

“We could delay the spin-up, if it was worth it,” Yalda suggested reluctantly. They could live off stunted wheat while they completed this shield, if it was actually going to be capable of protecting them.

Palladia said, “Let’s try to get some solid numbers.”

They worked together for ten days. Thanks to Marzia’s experiments they knew the rate at which calmstone burned, and though no one had yet been able to find one of the tiny impact sites on the surface, Yalda could estimate the depth to which dust particles of various masses would penetrate the cladding when they struck with infinite velocity. Palladia had surveyed the whole mountain during the construction phase, compiling the first detailed records of its composition, and she’d witnessed firsthand how various chambers had stood up to the stresses of the launch.

The numbers were not in their favor. To cover the mountain with a worthwhile protective layer would leave it gutted and weakened inside, to the point where its spin alone could start breaking it apart. But giving up on spin wouldn’t save them; the next time they fired the engines, to decelerate, the Peerless would turn to rubble.

“I want you to draw up plans for… our other option,” Yalda said.

Palladia regarded her with something close to panic.

“I’m not asking you to rush anything,” Yalda assured her. “You should take as long as you need to get this right. But you should make all your choices on the basis of structural considerations alone. We’ll address the other practicalities separately—if we have to move some pieces of equipment to safer locations, or duplicate some facilities, so be it.”

Palladia was still not happy. “When are you going to speak to Frido about this?”

Yalda said, “I’m speaking to you, because I know you can do the job. You can have as many assistants as you need—just pick whoever you want. You might have to wait until the spin engines are finished for some people to become available, but once that’s done this will be our highest priority.”

Palladia replied carefully, “I’m honored to be given this responsibility—but with respect, I think Frido and Babila should be involved. Assistants can follow instructions and check my calculations, but they won’t have the confidence to argue with me if I head down a wrong path. This is too important to be left to one person.”

Yalda could see the logic in that. “Why Frido and Babila?”

“They’re the most experienced engineers we have,” Palladia said. “Who else should I consult?”

She was afraid, Yalda realized. If something went wrong with the scheme and the Peerless ended up crippled and airless, the architects of the plan would be held accountable. Though Yalda would take most of the blame, anyone who had been too close to her on this would share the opprobrium. But if the most powerful members of the only other viable faction were equally enmeshed in the project, Palladia would have some protection in the aftermath.

Was that so unreasonable? And regardless of the politics, Yalda didn’t doubt that Frido and Babila would scrutinize the plans diligently. Whatever their disagreements, they were not going to jeopardize the Peerless itself just to undermine her.

“All right,” she said. “Let’s talk to Frido.”

They found Frido in his office. He listened patiently to their summary of the problem and the results of their calculations.

“Of course I’m happy to help,” he said. “But before we go any further, I think we should put this to a crew meeting—just as we did with the spin engines.”

Yalda said, “Why? The construction crews can handle this; we won’t be taking anyone away from their ordinary jobs.”

“No,” Frido agreed, “but it will still affect everyone. Having explosives set up all around the mountain is not the kind of change we should be making lightly.”

Yalda glanced at Palladia, but she remained silent. “It should be clear that we haven’t come to this lightly ,” Yalda said. “Are you in favor of the plan, or not?”

“Of course I’m in favor of it,” Frido replied calmly. “And I want to do everything I can to see it carried out, safely and successfully. The question is, how can we bring the crew along? Can we convince them that, in protecting the Peerless from external threats, this won’t increase the risk to their lives from the enemies within—from saboteurs?”

Yalda traveled down from the summit to check the preparations before the spin engines were fired. In the fields, the last of the crops to grow up from the old cavern floors were being harvested. In the gardens, workers shifted plants and netted soil onto walls that would soon be horizontal. A haze of dust and organic detritus filled these chambers, leaking out into the corridors and stairwells to dim the moss-light and coat every surface with black grime.

After consulting with Lavinio and the other agronomists, Yalda had decided to leave the forest untouched. It was near enough to the axis of the mountain to remain unaffected by centrifugal force, and the effort required to shift the whole tangled maze of full-grown trees—as well as capturing and moving the arborines—seemed disproportionate to any benefit, when all the plants and animals it contained were doing well enough without gravity.

Boards were being fitted over the helical grooves in the outer stairwells, to bridge the gaps in the floors of the tunnels they’d become. The ring corridors could be left as they were, their walls already traversable, but crews were busy fitting rope ladders to their radial offshoots.

Every factory, every workshop, every office needed to be rethought , if not literally reconstructed. But as Yalda traversed the length of the Peerless from field to mill to kitchen, from plantation to carpenter’s workshop, from the medicinal gardens to the holin store, everyone she spoke with accepted the upheaval without complaint.

This was not the time to tear people away from their work to confront them with the news of Palladia’s plan, and she doubted that Frido would be foolish enough to do that himself. While they were as busy as this, united by the common cause of rescuing the crops, no one would be interested in hearing about anything else.

When the work was done, though? Frido could undermine her whisper by whisper, spreading his own message about the new project, leaving people wondering why she hadn’t explained it to them herself. However she handled this, she would not be able to put off the confrontation for long.

Yalda waited in the observatory for the fireworks to begin. She’d invited her old work team to join her, but not everyone had accepted; there were observation chambers lower down offering much better views of the pyrotechnics. But she had something different in mind: she’d locked the big telescope on a point just above the horizon, so her companions could take a look and commit what they’d seen to memory. The flames pouring from the tunnels they’d helped carve into the slopes would be spectacular enough, but the actual proof of the engines’ efficacy would first appear as a tiny shift in the view through the telescope.

Fatima let go of the ropes she’d been holding and curled up in midair. “This is where you discovered rotational physics, isn’t it?”

“It must be,” Yalda replied, “but I don’t really recognize anything. The ground, the buildings… everything’s changed.” Even the telescope itself had been rebuilt, with the original lens inserted into a new frame.

“Someone should put a sign here,” Fatima suggested. “To commemorate it.”

“I’m sure that can wait until I’m dead.”

Yalda glanced at the clock beside the telescope; there were still three lapses left to ignition. Ausilia and her co were clinging to the lowest of the cleaners’ handles at the edge of the dome, peering down the mountain expectantly. Prospera and her friends were over near the entrance, daring each other to attempt ever more intricate ricochets off the clearstone panes. It would be hard to end up stranded in midair, and Yalda had no fear that they’d break the dome, but if anyone collided with the telescope she’d be annoyed.