“In the absence of gravity the dart just sails on, in a straight line, until it hits something.” She hefted the blowpipe. “It took me hours of practice before I felt confident with this thing in zero-gee; it was like learning from scratch all over again.”

Mark was nodding slowly. “So you think the Planners’ bowmen meant to hit us.”

“I’m sure of it. But they shot too high. They haven’t learned to adjust to zero gee; they certainly didn’t allow for it when they shot at us.”

Constancy-of-Purpose cupped her chin. “Maybe you’re right. But I don’t see how that helps us. Even if their aim is a little off, there are enough of them to blanket us with bolts if we try to get too close.”

“Yes,” Mark said, some excitement entering his artificial voice, “but maybe we can use Trapper’s insight in another way. She’s right; the Planners — everyone in that building — are failing to learn how to cope with the absence of gravity. In fact, they seem to be denying that the absence even exists.” He glanced around, staring at the tracery of ropes they’d laid from the access ramps as if seeing them for the first time. “And so have we. Look at the way we’ve traveled — abseiling across the floor, sticking to the familiar two dimensions to which gravity restricts us.”

Morrow frowned. “What are you suggesting?”

Mark raised his face to the iron sky. “That we try a little lateral thinking…”

At the origin of the weak, ancient signal Louise and Spinner found a worldlet. It was a dirty snowball three hundred miles across, slowly turning in the outer darkness.

When Louise bathed the worldlet with spotlights from her life-lounge, broken ice shone, stained with splashes of color: rust-brown, gray.

This lost little fragment followed a highly elliptical path, each of its distorted journeys lasting a million years or more. Its closest approach to the Sun came somewhere between the orbits of Saturn and Uranus, while at its furthest it got halfway to the nearest star — two light-years from the inner worlds.

“Bizarre,” Louise mused. “It’s got the orbital characteristics of a long-period comet — but none of the physical characteristics. In morphology it’s more like a Kuiper object, like Port Sol. But then it should be in a reasonably circular orbit…”

Spinner-of-Rope peered out of her cage at the dark little world, wondering what might still be living down there.

Here and there, in pits in the ice, metal gleamed.

“Artifacts,” Louise said. “Can you see that, Spinner? Artifacts, all over the surface.”

“Human?”

“I’d guess so. But I don’t recognize anything. And I doubt if there’s much still working…

“I’m taking radar scans. There are hundreds of chambers in there, in the interior. And our beacon’s somewhere inside: still broadcasting on all wavelengths, with a peak in the microwave range… Life knows what’s powering it.”

“Is this ice-ball inhabited? Is there anyone here?”

“I don’t know.” Spinner heard Louise hesitate. “I guess I’m going to have to go down to find out.”

The pod’s small jets flared across the worldlet’s uneven surface as Louise descended. Spinner watched; the pod was the only moving thing in all of her Universe.

“I’m close to the surface now,” Louise reported. “I’ll level off. They certainly made a mess of this surface. I think these artifacts are sections of ships, Spinner. Not that I can label much of it — so much of this technology must be tens of millennia beyond us… Lethe, I wish we had the time to spend here, to study all this stuff.

“But at least it’s human.” Her voice sounded strained. “The first traces of humanity we’ve found in the whole damn System, Spinner.

“I think people landed here, and broke up their ships for raw materials to occupy the interior.

“I’m going to land now. I see what looks like a port.”

Louise couldn’t find any way to open the wide, hatch-like port to the interior. Instead, she had to erect a plastic bubble to serve as an airlock over the port, and cut her way through, working slowly in the microgravity.

“All right, I’m in.” Her breath was scratchy, shallow — almost as if she were whispering, Spinner thought. “It’s dark here, Spinner. I have lamps; I’m going to leave a trail of them, as I go through.”

Spinner, listening in her cage, prayed that nothing bad happened to Louise down there. If it did, what could she — Spinner — do? Would she have the courage even to try a landing on the ice worldlet?

Doubt flooded her, a feeling of inadequacy, of being unable to cope…

You’ll manage, Spinner-of-Rope.

That same dry, sourceless voice.

Strangely, her fears seemed to subside. She glanced around; of course, she was alone in the cage, with the nightfighter suspended passively over the ice worldlet. But still — again — she had had the impression that someone was here with her. She couldn’t see him, or her — but somehow she knew there was nothing to fear; she sensed a massive, comforting presence similar to her own, lost father.

But still — hearing voices? What in Lethe is going on inside my head?

“…Lots of chambers,” Louise said a little breathlessly. “They are boxes, carved out of the ice and plated over with metal and plastic. A bit cramped… There is air here, but foul; I won’t be breaking my suit seal. This was definitely a human colony, Spinner. But it’s all — neat. Tidy; abandoned in an orderly way.

“I guess they took a long time to die. They had time to clear up after themselves — to bury their dead, maybe, even, as they withdrew. I guess they went deeper as their numbers dwindled, toward the center of the world… It’s kind of dignified, don’t you think? There are no signs of panic, or conflict. I wonder how we would behave, in the same circumstance. Spinner, I’m going on now.”

Later: “I’m in a deeper layer of chambers. I think I’ve found the source of the signal.” She was silent for a while. Then, “They sure built this to last.”

“Well, they got that right.”

“I still can’t identify what’s powering it… I guess one of the ship’s GUTdrive plants on the surface. I think they used nanobots to maintain the beacon, Spinner. Maybe they adapted AS nanobots from their medical stores.” Her tone of voice changed, subtly, and Spinner imagined her smiling. “They were determined to enable this to survive. But it’s been millions of years… and the ’bots have made a few cumulative mistakes. The damn thing looks as if it’s melted, Spinner. But it’s still pumping out its signal, so we can’t criticize too much…”

“Louise,” Spinner asked slowly, “why were these people here? What were they trying to do?”

Louise thought for a while. “Spinner, I think they were trying to escape.”

This ice-world was typical of the small, subplanetary bodies which could once have been found throughout the Solar System, Louise said, shepherded into orbital clusters by the major planets.

“But,” Louise said, “the orbits of many of those little bodies were only semi-stable. Their orbits were intrinsically chaotic, you see… That means, over a long enough time period the minor bodies could move out of their stable pathways. They could even fall into the gravity wells of the major planets and be flung out of the System altogether. It’s a form of evaporation — an evaporation of worlds and moons out of stellar systems. In fact, over a long enough scale — and I’m talking tens of billions of years now — the same thing would happen to the major planets too — and to stars, which could evaporate out of their parent galaxies… If,” she went on sourly, “they had ever been given the chance.”

“So you think this little world just evaporated away from Sol, gravitationally?”