Alastair Reynolds - Century Rain

“I can do without the countdown, Tunguska,” Auger said, bracing herself. “Just tell us if we’re still alive at the end of it.”

She felt, when it happened, some ghostly report of the blast, even though Tunguska assured her that no signals could possibly reach her through the barricades he had put in place. It was long and drawn out, like a distant peel of thunder.

“The Molotov device has detonated,” Tunguska said. “And we, self-evidently, are still alive.”

“I was being sarcastic.”

“I wasn’t. It’s always good to confirm these things.”

When the expendable sensors deemed it safe, Tunguska unshuttered the ship’s more delicate eyes and turned them on the scene of the crime. It took a little while for them to make sense of the data, for the view was obstructed by a slowly expanding debris plume, spreading away from the impact point like a cherry-red fountain. Auger grappled with the scale, but she still couldn’t adjust to the mind-numbing size of the ALS object. The plume was huge—hundreds of thousands of kilometres across and still growing—but it was just a tiny detail on the surface of the sphere.

“Debris is clearing near the epicentre,” Tunguska said. “The view is foreshortened, so it isn’t easy to see exactly what damage has been done.”

“Just show us what you’ve got,” Auger said.

They had to wait twenty minutes until the plume had dissipated sufficiently, and their angle of observation improved enough, to allow a clearer view. By then, Tunguska’s ship was following the same arcing trajectory as Niagara’s, curving around for a hard interception with the ALS. They were still sustaining five gees, cocooned against harm.

“They’ve broken through,” Tunguska said.

He pushed an image into Auger’s head. The Molotov device had punched a surprisingly neat little entry wound into the skin of the ALS. The hole was a hundred kilometres across and nearly circular. The kilometre-thick skin glowed painfully brightly around the edge of the hole, shading down through blue and yellow and charred red out to a distance of perhaps two or three hundred kilometres from the epicentre. There were hints of wild, lashing structures in the exposed cross section, flailing like severed nerve endings.

“Dear Christ,” Auger said. “They did it. The damned thing didn’t put up any kind of fight at all.”

“Did you expect it to?” Floyd asked.

“I expected something .”

“What about the other ship?”

“Still tracking it,” Tunguska said. “She’s under thrust and maintaining the course she was following before the blast. It will take her through the wound in under ten minutes.”

Maybe he shouldn’t have been so concerned about the state of Niagara’s shielding, she thought. “I take it we’re still not within beam range?”

“No.” Tunguska sounded genuinely embarrassed. “We’ll have to follow her in for that.”

“Through the wound?”

“Yes,” Tunguska said. “Into the ALS. I’m afraid it’s the only course available to us.”

By the time they were about to pass through the hole that Niagara had punched into the ALS, the debris cloud had completely cleared. The wound remained raw and bright, spilling a faint shaft of re-radiated golden-white light back into space, twinkling off the few remaining shards of hot matter still hanging around the impact site.

“That light has the spectrum of solar radiation,” Tunguska said, when they were falling down the column of light. “It’s a perfect match for the Sun, at the limit of our instruments.”

The transition between outside and inside happened in an eyeblink. One kilometre of shell thickness was nothing compared to their speed. One moment the surface of the sphere was swelling larger, with the wound growing rapidly from a searing, white-rimmed eye to a swallowing mouth… and then they were through, falling towards the heart of the ALS.

Tunguska’s sensors took immediate stock of the interior. Behind his ship, the receding wound embraced a circle of the perfect blackness of interstellar space. It was rimmed with bright, agonised matter on this side as well. But instead of the quilted blue-grey material of the outer skin, the inner surface of the ALS was made of something far stranger; something far less susceptible to easy interrogation by Tunguska’s instruments.

They had always known that the inner surface of the shell had to function as a kind of near-perfect planetarium, projecting an image of the sky that would have been seen from the original Earth. There were false stars, their brightness and colours reproduced precisely, aligned into exactly the right constellations that the inhabitants of E2 had learned to expect. Some fraction of the stars must even have been programmed for variability—to dim and brighten according to intricate astrophysics-rich algorithms. They were all required to move with respect to each other, following the slow, stately currents of proper motion, or the wheeling gyre of binary orbits.

Beyond the stars, there were galaxies, vast shoals of them in every direction. Each and every galaxy had to stand up to the same scrutiny as the stars. Novae and supernovae had to flare and die… whether they were noticed or not.

It was awesome and astonishing. It was also doomed to failure, for no such tapestry could ever have withstood arbitrarily close study using the kind of astronomical tools available in Auger’s era. Even a simple interplanetary probe would have eventually sniffed out something odd about those stellar positions… just before it dashed itself to atoms by colliding with the inner surface of the shell. No: it wasn’t perfectly foolproof, nor must that ever have been the intention of its builders. It was good enough to withstand examination using the crude science of Floyd’s time, but it was never the intention that the shell should form an utterly convincing illusion. Sooner or later, it must have been assumed, the inhabitants of E2 were bound to discover the truth. The function of the ALS was to protect them from outside interference until precisely that moment. After that—at which point they would probably direct their energies into breaking through the shell—they were on their own.

But there was already something amiss with the view of the heavens around the inside edge of the open wound. For thousands of kilometres in all directions, the stars were distorted, elongated and spermlike, their stretched, tapering tails pointing like accusing fingers towards the hole Niagara had made.

“The zone of distortion is spreading,” Tunguska said. “Frankly, they’re going to have a hard time not noticing that on the Earth, even if they somehow missed the initial flash.”

“What will they make of it?” Auger wondered.

“I don’t know. But if an inexplicable astronomical puzzle is all they have to worry about by the end of the day, they’ll be doing rather well.”

“Can we shoot that shuttle down yet?” she asked.

“No,” he replied. “But I’m ready to squeeze a little more out of the bleed-drive. If my estimates are good, we still have a chance of intercepting her before she hits the atmosphere.”

“Don’t hesitate, Tunguska.”

“I won’t. There is something I feel I should mention, though. It’s just an observation, and it may be misleading.”

Auger didn’t like the sound of that at all. “Tell us anyway.”

“The wound appears to be healing itself. The aperture was more than a hundred kilometres across immediately after the detonation of the Molotov device.”

“And now?”

“A shade under a hundred. It may not mean anything—it’s rather difficult to define the precise boundary—but I thought I should draw it to your attention.”