Blinding light. She gasped.

The image snapped back to an overview of the moon. She felt as if she had died and come back to life.

A plume of fragments was rising vertically from Triton’s surface, like one last mighty geyser: bits of red-hot rock, steam, glittering ice, some larger fragments that soared like cannonballs.

Nereid was gone.

Much of the little moon’s substance must already have been lost, rock and ice and rich organic volatiles blasted to vapor in that first second of impact: lost forever, lost to space. Perhaps it would form a new, temporary ring around Neptune; perhaps eventually, centuries from now, some of it would rain back on Triton, or some other moon.

This was an astoundingly inefficient process, she knew, and that had been a key objection of some of the Kasyapa factions. To burn up a moon, a whole four-billion-year-old moon, for such a poor gain is a crime. Madeleine couldn’t argue with that.

Except to say that this was war.

And now something emerged from the base of the plume. It was a circular shock wave, a wall of shattering ice like the rim of a crater, plowing its way across the ground. The terrain it left behind was shattered, chaotic, and she could see the glint of liquid water there, steaming furiously in the vacuum and cold. Ice formed quickly, in sheets and floes, struggling to plate over the exposed water. But echoes of that great shock still tore at this transient sea, and immense plates, diamond white, arced far above the water before falling back in a flurry of fragments.

Now, in that smashed region — from cryovolcanoes kilometers wide — volatiles began to boil out of Triton’s interior: nitrogen, carbon dioxide, methane, ammonia, water vapor. Nereid’s heat was doing its work; what was left of the sister moon must be settling toward Triton’s core, burning, melting, flashing to vapor. Soon a mushroom of thickening cloud began to obscure the broken, churning surface. Some of the larger fragments thrown up by that initial plume began to hurtle back from their high orbits and burn streaks through Triton’s temporary atmosphere. And when they hit the churning water-ice beneath, they created new secondary plumes, new founts of destruction.

The shock wall, kilometers high, plowed on, overwhelming the ancient lands of ice, places where nitrogen frost still lingered. It was not going to stop, she realized now. The shock would scorch its way around the world. It would destroy all Triton’s subtlety, churning up the nitrogen snows of the north, the ancient organic deposits of the south, disrupting the slow nitrogen weather, destroying forever the ancient, poorly understood cantaloupe terrain. The shock wall would be a great eraser, she thought, eliminating all of Triton’s unsolved puzzles, four billion years of icy geology, in a few hours.

But those billowing ice-volcano clouds were already spreading in a great loose veil around the moon, the vapor reaching altitudes where it could outrun the march of the shattered ice. Mercifully, after an hour, Triton was covered, the death of its surface hidden under a layer of roiling clouds within which lightning flashed, almost continually.

She heard from Ben that the Yolgnu were celebrating. This was Triton Dreamtime, the true Dreamtime, when giants were shaping the world.

After three hours there was a new explosion, a new gout of fire and ice from the far side of the moon. That great shock wave had swept right around the curve of the moon until it had converged in a fresh clap of shattered ice at the antipode of the impact. Madeleine supposed there would be secondary waves, great circular ripples washing back and forth around Triton like waves in a bathtub, as the new ocean, seething, sought equilibrium.

Nemoto materialized before her.

“You improvised well, Madeleine.”

“Don’t patronize me, Nemoto. I was a good little soldier.”

But Nemoto, of course, five hours away, couldn’t hear her. “…Triton is useless now to the Gaijin, who need solid ice and rock for their building programs. But it is far from useless to humans. This will still be a cold world; a thick crust of ice will form. But that ocean could, thanks to the residual heat of Nereid and Neptune’s generous tides, remain liquid for a long time — for millions of years, perhaps. And Earth life — lightly modified anyhow — could inhabit the new ocean. Deep-sea creatures — plankton, fish, even whales — could live off the heat of Triton’s churning core. Triton, here on the edge of interstellar space, has become Earthlike. Imagine the future for these Aborigines,” Nemoto said seductively. “Triton was the son of Poseidon and Aphrodite. How apt…”

This was Nemoto’s finest hour, Madeleine thought, this heroic effort to deflect not just worlds, but the course of history itself. She tried to cling to her own feelings of triumph, but it was thin, lonely comfort.

“One more thing, Meacher.” Virtual Nemoto leaned toward her, intent, wizened. “One more thing I must tell you…”

Later, she called Ben.

“When are you coming home?” he asked.

“I’m not.”

Ben frowned at her. “You are being foolish.”

“No. Kasyapa is your home, and Lena’s. Not mine.”

“Then where? Earth? The Moon?”

“I am centuries out of my time,” she said. “Not there either.”

“You’re going back to the Saddle Points. But you are the great Gaijin hater, like Nemoto.”

She shrugged. “I oppose their projects. But I’ll ride with them. Why not? Ben, they run the only ship out of port.”

“What do you hope to learn out there?”

She did not answer.

Ben was smiling. “Madeleine, I always knew I would lose you to starlight.”

She found it hard to focus on his face, to listen to his words. He was irrelevant now, she saw. She cut the connection.

She thought over the last thing Nemoto had said to her. Find Malenfant. He is dying…

Chapter 23

Cannonball

It had to be the ugliest planet Madeleine had ever seen.

It was a ball the size of Earth, spinning slowly, lit up by an unremarkable yellow star. The land was a contorted, blackened mess of volcano calderas, rift and compression features, and impact craters that looked as if they had been punched into a metal block. Seas, lurid yellow, pooled at the shores of distorted continents. And the air was a thin, smoggy, yellowish wisp, littered with high mustard-colored cirrus clouds.

On the planet there were no obvious signs of life or intelligence: no cities gleaming on the dark side, no ships sailing those ugly yellow oceans. But there were three Gaijin flower-ships in orbit here, Madeleine’s and two others.

Her curiosity wasn’t engaged.

All the Gaijin would tell her about the planet was the name they gave it — Zero-zero-zero-zero — and the reason they had brought her here, across a hundred light-years via a hop-skip-jump flight between Saddle Point gateways in half a dozen systems, a whole extra century deeper into the future: that they needed her assistance.

Malenfant is dying.

Reluctantly — after a year in transit, she had gotten used to her lonely life in her antique Gurrutu hab module — she collected her gear and clambered into a Gaijin lander.

Madeleine stepped onto the land of a new world.

Ridges in the hard crumpled ground hurt her feet. The air was murky gray, but more or less transparent; she could see the Sun, dimmed to an unremarkable disc as if by high winter cloud. Immediately she didn’t like it here. The gravity was high — not crushing, but enough to make her heavy-footed, the bio pack on her back a real burden.

Numbers scrolling across her faceplate told her the gravity was some 40 percent higher than Earth’s. And, since this world was about the same size as Earth, that meant that its density had to be around 40 percent higher too: closer to the density of pure iron.