And already his roots were crumbling, withdrawing.

In his rage he lunged past the hypothesis-fruit and up at the Sky, stabbed at its bland completeness, poured all his energies against it!

...And, for a precious instant, he reached beyond the Sky, and into something warm, yielding, weak. A small patch of the Sky was dulled, as if bruised.

He recoiled, exhausted, astonished at his own anger.

The Sky curved over him like an immense, shining bowl as he shriveled back to the Culled base floor, he and millions of bud-siblings, their faces turned up to that forever unreachable light...

No, he told himself as the emptiness of the Cull sank into his awareness. Not forever. Each time I, the inner I, persists through the Cull. Just a little, but each time a little more. I will emerge stronger, more ready, still hungrier than before.

And at last, he thought, at last I will burst through the Sky. And then there will be no more Culls.

Shrieking, he dissolved into the base Cull floor.

The flitter was new, cramped and smelled of smooth, clean plastic, and it descended in silence save for the precise hiss of its jets. It crunched gently into the surface of Nereid, about a mile from Marsden's dome.

Chen peered through the cabin windows at the shabby moonscape. Marsden's dome was just over the compact horizon, intact, sleek, private. "Lethe," Chen said. "I always hated assignments like these. Loners. You never know what you're going to find."

Hassan laughed, his voice obscured as he pulled his face plate down. "So easily shocked? And I thought you police were tough."

"Ex-police," Chen corrected automatically. She waved a gloved hand at the dome. "Look out there. What kind of person lives alone, for years, in a forsaken place like this?"

"That's what we've been sent to find out." Bayliss, the third person in the flitter, was adjusting her own headgear with neat, precise movements of her small hands. Chen found herself watching, fascinated; those little hands were like a bird's claws, she thought with faint repulsion. "Marsden was a fine physicist," Bayliss said, her augmented eyes glinting. "Is a fine physicist, I mean. His early experimental work on quantum nonlinearity is still--"

Hassan laughed, ignoring Bayliss. "So we have already reached the limits of your empathy, Susan Chen."

"Let's get on with this," Chen growled.

Hassan cracked the flitter's hatch.

One by one they dropped to the surface, Chen last, like huge, ungainly snowflakes. The Sun was a bright star close to this little moon's horizon; knife-sharp shadows scoured the satellite's surface. Chen scuffed at the surface with her boot. The regolith was fine, powdery, ancient. Undisturbed. Not for much longer.

Beyond Marsden's dome, the huge bulk of Neptune floated, Earth-blue, like a bloated vision of the home planet. Cirrus clouds cast precise shadows on oceans of methane a thousand miles below. The new wormhole Interface slid across the face of Neptune, glowing, a tetrahedron of baby-blue and gold. Lights moved about it purposefully; Chen peered up longingly.