He had gotten straight to the point. “The comet is history, babe.”

At first she hadn’t understood. “I thought it was going to supply us all with volatiles. I thought it was going to be the demonstration we needed that Prometheus was a sound investment.”

“Yeah. But it doesn’t pan out.” Frank had tapped the surface of his desk, which lit up with numbers, graphics. “Look at the analysis. We’ll get some volatiles, but most of the nucleus’s mass will be blasted back to space. Comets are spectacular fireworks, but they are inefficient cargo trucks. However you steer the damn things down, most of the incoming material is lost. I figure now you’d need around a thousand impactors to future-proof the Moon fully, to give it a stable atmosphere, thick enough to persist over significant periods before leaking away. And we aren’t going to get a thousand impactors, not with the fucking Gaijin everywhere.” He had looked thoughtful, briefly. “One thing, though. Did you know the Moon is going to get an atmosphere out of this? It will last a thousand years—”

“Iroonda.”

“No, it’s true. Thin, but an atmosphere, of comet mist. Happens every time a comet hits. Carbon dioxide and water and stuff. How about that.” He shook his head. “Anyhow it’s no use to us.”

“Frank, how come nobody figured this out before? How come nobody questioned your projections?”

“Well, they did.” He had grinned. “You know I’m never too sympathetic when people tell me something is impossible. I figured there would be time to fix it, to find a way.”

This was, on the face of it, a disaster, Xenia knew. Project Prometheus had gotten as far as designs for methane rockets, which could have pushed Oort comets out of their long, slow, distant orbits and brought them in to the Moon. The project had consumed all Frank’s energies for years, and cost a fortune. He needed investors, and had hoped this chance comet impact, a proof of concept, would bring them in.

And now, it appeared, it had all been for nothing.

“Frank, I’m sorry.”

He seemed puzzled. “Huh? Why?”

“If comets are the only source of volatiles—”

“Yesterday I thought they were. But look at this.” He had tapped his softscreen and was talking fast, excited, enthusiastic, his mind evidently racing. “There’s a woman here who thinks there are all the volatiles you could want, a hundred times over, right here on the Moon. Can you believe that?”

“That’s impossible. Everyone knows the Moon is dry as a bone.”

He had smiled. “That’s what everyone thinks. I want you to find this woman for me. The author of the paper.”

“Frank—”

“And find out about mining.”

“Mining?”

“The deeper the better.” His grin widened. “How would you like a journey to the center of the Moon, baby?”

And that was how she had first learned about Frank’s new project, his new obsession, his latest way to fix the future.

Ten seconds. Five. Three, two, one.

Stillness, for a fraction of a second. Then there was a clatter of explosive bolts, a muffled bang.

Xenia was ascending as if in some crowded elevator, pressed back in her bucket seat by maybe a full g. Beyond her window, stray dust streaked away across the pad glass, heaping up against fuel trucks and pipelines.

But then the shuttle swiveled sharply, twisting her around through a brisk ninety degrees. She heard people gasp, children laugh. The shuttle twisted again, and again, its attitude thrusters banging. This lunar shuttle was small, light, crude. Like the old Apollo landers, it had a single fixed rocket engine that was driving the ascent, and it was fitted with attitude control jets at every corner to turn it and control its trajectory. Just point, twist, squirt, as if she were a cartoon character carried into the air by hanging onto an out-of-control water hose.

Three hundred meters high the shuttle swiveled again, and she found she was pitched forward, looking down at the lunar surface, over which she skimmed. They were rising out of lunar night, and the shadowed land was dark, lit here and there by the lights of human installations, captured stars on dark rock. She felt as if she were falling, as if the ascent engine was going to drive her straight down into the unforgiving rocks. Sunrise. Wham.

It was not like Earth’s slow-fade dawn; the limb of the Sun just pushed above the Moon’s rocky horizon, instantly banishing the stars into the darkness of a black sky. Light spilled on the unfolding landscape below, fingers of light interspersed with inky black shadows hundreds of kilometers long, the deeper craters still pools of darkness. The Moon could never be called beautiful — it was too damaged for that — but it had a compelling wildness.

But everywhere she could see the work of humans: the unmistakable tracks of tractors, smooth lines snaking over the regolith, and occasional orange tents that marked the position of emergency supply dumps, all of it overlaid by the glittering silver wires of mass driver rails.

The shuttle climbed farther. The Lunar Japanese around her applauded the smooth launch.

Now Earth rose. It looked as blue and beautiful as when she and Frank had left for the stars. But it had changed, of course. Even from here, she could see Gaijin flower-ships circling the planet, the giant ramscoops of the alien craft visible as tiny discs. She felt a stab of antique resentment at those powerful, silent visitors who had watched as humanity tore itself apart.

And now, as the shuttle tilted and settled into its two-hour orbit around the Moon, Xenia saw a sight she knew no human had ever seen before today:

Comet rise, over the Moon.

The coma, a diffuse mass of gas and fine particles, was a ball as big as the Earth, so close now it walled off half the sky, a glare of lacy, diffuse light. Massive clumps in the coma, backlit, cast shadows across the smoky gases, straight lines thousands of kilometers long radiating at her. The comet was coming out of the Sun, straight toward the Moon at seventy thousand kilometers an hour. She looked for the nucleus, a billion-ton ball of ice and rock. But it was too small and remote, even now, a few minutes from impact. And the tail was invisible from here, fleeing behind her, running ahead of the comet and stretching far beyond the Moon, reaching halfway to Mars in fact.

Suddenly there was light all around the shuttle. The little ship had plunged inside the coma. It was like being inside a diffuse, luminous fog.

“Vileekee bokh.”

Frank leaned across her, trying to see. He was seventy years old, physiological; his nose was a misshapen mass of flesh. He was a small, stocky man, with thick legs and big prizefighter muscles built for Earth’s gravity, so that he always looked like some restless, half-evolved ape alongside the tall, slim Lunar Japanese.

“Eta prikrasna,” Xenia murmured.

“Beautiful. Yeah. How about that: we’re the last off the Moon.”

“Oh, no,” she said. “There’s a handful of old nuts who won’t move, no matter what.”

“Even for a comet?”

“Takomi. He’s still there, for one,” she said.

“Who?”

“He’s notorious.”

“I don’t read the funny papers,” Frank snapped.

“Takomi is the hermit out in the ruins of Edo, on Farside. Evidently he lives off the land. He won’t even respond to radio calls.”

Frank frowned. “This is the fucking Moon. How does he live off the land? By sucking oxygen out of the rock?…”

The light changed. There was a soft Fourth-of-July gasp from the people crammed into the shuttle.

The comet had struck the Moon.

A dome of blinding white light rose like a new Sun from the surface of the Moon: comet material turned to plasma, mixed with shattered rock. Xenia thought she could see a wave passing through the Moon’s rocky hide: a sluggish ripple in rock turned to powder, gathering and slowing.