Redwing looked puzzled.

Beth gave him a weak smile. “I’m going to sleep.”

She staggered out. Behind her she heard Redwing’s, “How can anyone leave this?”

And then Cliff was with her, guiding her, but lurching a little himself.

FOUR

Beth thrashed and jerked awake. The hammock shuddered. Her legs and arms were cramping from armpit to fingertips, hip to toes.

The dream faded. The controls weren’t under her hands; the ship wasn’t roaring through a plume of star-hot plasma. She hugged herself and tried to sleep. Cliff wasn’t there. How long had she been sleeping?

Presently she gave up and went to the bridge, her boots thumping, bringing her fully awake. Her hands were trembling, though. Not what you want in a pilot …

“Hi,” Cliff said, grinning. “Redwing left me on watch. Abduss is computing an orbit for us, unless he flaked out, too.”

Beth was famished. She got out bread and fruit and ate as she watched the displays. She was just a little jealous of the others, who must have been watching for hours. And it was glorious.

Structures fanned out from the Knothole. She was now watching from the other side, gazing down at a vast sprawl. Her eyes kept tricking her, making her think this was all nearby, like looking down on Earth … but she was gazing over interplanetary distances. The tubing around the Knothole must be tremendous, the size of continents.

Far below the ship stretched away the wok-shaped mirrored shell, faring into a ring of green-tinged ocher. Between SunSeeker and those lands was a shimmering layer—atmosphere, she guessed. Held in … how? She squinted and thought she could catch a sheen, the star reflecting from some transparent barrier. A membrane? She squinted at what seemed like millions of square kilometers of clear plastic sandwich wrap. The diffuse layer stretched away toward the distance, where she saw the lands of the belt—the great cylindrical section that formed the thick rim of … Cupworld? She didn’t like Redwing’s term but couldn’t think of a better one. No mirrors there. Continents, yes, cloud-shrouded and green. Deserts as well, sandy and bright under the unending glare of a star that never set. Indeed, never set on all this colossal construction. And what lives here?

Her hands were trembling even more.

This immensity was impossible, too much; Beth looked away.

“They’ve made a world … a habitat out of the bowl,” Mayra said wonderingly. “A vast green thing.”

Beth took a long breath. For safety—pilots must be focused—she took her hands off the command boards.

Cliff thumbed up a display board. “We worked up a sketch to get the essentials of this thing in one view. Have a look.”

She studied the line drawing, feeling woozy. “Yes, right. You’ve labeled the regions out from the axis with the equivalent gravs…”

“Yup, and the clumps in the edge plain are supposed to be topological features. Only my splotches are bigger than whole planets, a lot bigger.” He waved his hands helplessly, grinning. But he frowned, too, worried at her fatigue.

“Right, hard to grasp the scale—this is inconceivable, but a sketch helps. You caught how the jet bulges out near the star.”

More hand waving. “Looks to me like the magnetic fields in it are getting control, slimming it down into a slowly expanding straw…”

“A wok with a neon jet shooting out the back … and living room on the inside, more territory than you could get on the planets of a thousand solar systems. Pinned to it with centrifugal grav…”

“They don’t live on the whole bowl. Just the rim. Most of it is just mirrors. Even so, it’s more than a habitat,” said Cliff. “It’s accelerating. That jet! This whole thing is going somewhere. A ship that is a star. A ship star. We humans only built a star ship.”

*   *   *

There wasn’t much redundancy among SunSeeker’s auxiliary boats. Designs were modular: tanks or skeletal cargo carriers could substitute for passenger shells.

There were two fliers, Hawking and Dyson, twin lifting body designs. “We can’t use reentry vehicles,” Redwing decided. “We’d tear holes in whatever’s holding the air in.”

Abduss said, “Captain, these are the tankers.”

“Ceres and Eros are tankers, too, for mining asteroids. We just add the tank,” Redwing said.

Mayra said, “There aren’t any asteroids or comets. The locals must have cleaned out everything that might have threatened their habitats, or even used it all to build the bowl.”

“Really?”

“We haven’t found anything at all,” Mayra said.

“What, in four days? Four days to do a thousand years’ worth of astronomy in a brand-new solar system?”

The Wickramsinghs were silent before Redwing’s sarcasm. Indeed, the autoinventory had found no asteroids. “It’s been vacuumed clean.”

“Um,” Redwing said. “So nothing hits the bowl.”

Cliff listened with half his attention; this wasn’t his business yet. The automatic search cameras were smart, quick. Probably Mayra was right: The whole solar system had been scoured long ago. But he didn’t want to cross Redwing over a minor point; best to husband his credit with the irascible captain. The man had gone without much sleep, too. Cliff had found him pacing the corridors, checking and rechecking ship status, when he was supposed to be asleep.

He wished he had someone else to talk to about this, but the Wickramsinghs kept their own counsel. And Beth was sleeping. She’d done a lot of that, still recovering from cold sleep and the grueling flight through the Knothole.

Redwing chopped air with his hand. “Okay, for the moment we’ll take that as given. No asteroids, no comets. We’ll put a tank on Eros. It can carry water, mine it out of a comet, even—and it can land. Landing legs and a high-thrust fusion motor. We thought there’d be moons.”

Mayra asked blandly, “Where are you planning to land, Captain?”

“Down there.” Redwing waved toward Cupworld’s green-tinged rim.

“Yes, I thought so. If you land near the Knothole, you’ll be millions of klicks from any water source, and right on top of the systems that shape the electromagnetic fields. We could be perceived as a threat.”

Redwing blinked. “You think so?”

Mayra kept her face blank, apparently her way of being diplomatic. “We have no idea how the builders of this thing feel about visitors.”

Cliff couldn’t resist saying, “At least they didn’t shoot at us.”

Redwing grimaced; he had not been chosen for fighting skills. “They haven’t tried to talk to us. I don’t like that.”

Cliff put in, “But, Captain, the rim is where all the water and farmland is. They must live there.”

Mayra added, “It’s spinning around at thirty-four klicks per second, too.”

Redwing nodded. “Higher than our orbital speed, right? Do we have onboard fuel to catch up with that spin?”

Abduss said, “It will take a significant fraction of our onboard reserves, principally water for the nuclear rocket.”

Redwing snorted. “All our onboard ships are fusion powered. We can fly wherever we like if we can get water from Cupworld. We’ll need the same trick to use any of them. Okay, say we see a lake. We’ll put SunSeeker in a nearer orbit and drop the lander from there. Beth will know how to do that. Cliff!”

Cliff jumped.

“Where shall we land?”

They were asking him as the biologist. “It all looks like farmland and meadows and forests,” he said. “Different habitats, probably—see those ice fields? I don’t know how they create those, but our telescopes can’t make out individual trees. All I’ve got is a light spectrum, but clearly from spectral reflections, the plants are using chlorophyll, Captain. Land anywhere near water on the rim, I’d say, and refuel the tanks first thing.”