Louise felt an absurd, sentimental lump rise to her throat as she studied the slowly turning planet. At moments like this she felt impelled to make private vows about spending more time here: here, at the vital core of the System, rather than on its desolate edge.

…But, she reminded herself harshly, the rim was where the Northern was being built.

Louise had work to do. She was trying to equip a starship, damn it. She didn’t have the time or energy to hop back to Earth to play guessing games with some unseen authority.

Growling subvocally, Louise rested her head against her couch and tried to sleep. Mark, patient and placid, called a new page of his bookslate.

The little ship landed in North America, barely thirteen hours after leaving Port Sol — all of four billion miles away. The flitter brought them to a small landing pad near the heart of Central Park, New York City. Louise saw two people — a man and a woman — approaching the pad across the crisp grass.

The flitter’s autopilot told them to make their way to a small, anonymous-gray building close to the pad.

Louise and Mark emerged into the sunshine of a New York spring. Louise could see the shoulders of tall, ancient skyscrapers at the rim of the park, interlaced by darting flitters. Not far away, shielded by trees at the heart of the park, she made out one of the city’s carbon-sequestration domes. The dome was a sphere of dry ice four hundred yards tall: sequestration was an old Superet scheme, with each dome containing fifty million tons of carbon dioxide boldly frozen out of the atmosphere and lagged by a two-yard layer of rock wool.

Mark raised his face to the Sun and breathed deeply. “Mmm. Cherry blossom and freshly cut grass. I love that smell.”

Louise snorted. “Really? I didn’t know cherry trees grew wild, on Titan.”

“We have domes,” he said defensively. “Anyway, every human is allowed to be sentimental about a spring day in New York. Look at those clouds, Louise. Aren’t they beautiful?”

She looked up. The sky was laced by high, fluffy, dark clouds. And beyond the clouds she saw crawling points of light: the habitats and factories of near Earth space. It was a fine view — but quite artificial, she knew. Even the clouds were fakes: they were doped with detergent, to limit the growth of the water droplets which comprised them. Smaller droplets reflected more sunlight than larger ones, making the semi-permanent clouds an effective shield against excessive Solar heating.

So much for sentiment. Everything was manufactured.

Louise dropped her head. As always on returning to Earth, she felt disoriented by the openness of the sky above her — it seemed to counter every intuition to have to believe that a thin layer of blue air could protect her adequately from the rigours of space.

“Come on,” she said to Mark. “Let’s get this over with.”

Following the instructions of the autopilot they approached the nearby building. The structure was brick-shaped, perhaps ten feet tall; there was a low doorway in the center of its nearest face.

As they got closer, the two people Louise had noticed from the air walked slowly toward them from the rear of the building.

The two parties stared at each other curiously.

The man stepped forward, his hands behind his back. He was thin and tall, physical-fifty, with a bald, pallid scalp fringed by white hair. He stared frankly at Louise. “I know your face,” he said.

Louise let her eyebrows lift. “Really? And you are — ”

“My name is Uvarov. Garry Benson Deng Uvarov.” He held out his hand; his voice had the flat, colorless intonation of the old Lunar colonies, Louise thought. “My field is eugenics. And my companion — ” He indicated the woman, who came forward. “This is Serena Milpitas.”

The woman grinned. She was plump but strong-looking, about physical-forty, with short-cropped hair. “That’s Serena Harvey Gallium Harvey Milpitas,” she said. “And I’m an engineer.”

Uvarov gazed at Louise, his eyes a startling blue. “It’s very pleasant to meet you, Louise Ye Armonk. I’ve followed the construction of your starship with interest. But I am a busy man. I’ll be very pleased to learn why you’ve summoned us here.”

“Me too,” Milpitas growled. She had the lazy, nasal pitch of a Martian.

Louise felt confused. “Why I summoned you… ?”

Mark stepped forward and introduced himself. “I think you’ve got it wrong, Dr. Uvarov. We don’t know any more than you do, it seems. We were summoned too.”

Louise stared at Uvarov, feeling an immediate dislike for the man gather in her heart. “Yeah. And I bet we had further to come than you, too.”

Mark looked sour. “First blood to you, Louise. Well done. Come on; the only way we’re all going to get away from here is to go through with this, it seems.”

Striding confidently, he led the way toward the low building.

Studying each other suspiciously, the rest followed.

Louise passed through the squat, open doorway — and was plunged immediately into the darkness of space.

She heard Mark gasp; he stopped a pace behind her, his step faltering. She turned to him. He’d raised his head to a darkened dome above them; a sliver of salmon-pink (Jovian?) cloud slid across the lip of the dome, casting a light across his face, a light which softened the shadows of his apparent age. She reached out and found his hand; it was thin, cold. “Don’t let it get to you,” she whispered. “It’s just a stunt. A Virtual trick, designed to put us off balance.”

He pulled his hand away from hers; his fingernails scratched her palm lightly. “I know that. Lethe, you’ll never learn to stop patronizing me, will you?”

She thought of apologizing, then decided to skip it.

Uvarov walked forward briskly — hoping, it seemed, to catch the Virtual projectors of this illusion off guard. But the chamber moved past him fluidly, convincingly, shadows and hidden aspects unfolding with seamless grace.

The four of them were in a dome, a half-sphere a hundred yards across. At the geometric center of the dome were tipped-back control couches. A series of basic data entry and retrieval desks clustered around the couches. The rest of the floor area was divided by shoulder-high partitions into lab areas, a galley, a gym, a sleeping area and shower. The shower was enclosed by a spherical balloon of some clear material — obviously designed for zero-gee operation, Louise thought.

The sleeping zone contained a single sleep pouch. There was a noticeable absence of decoration — of any real sign of personality, Louise thought. There was no concession to comfort — no sign of entertainment areas, for example. Even the gym was functional, bare, little more than an open coffin surrounded by pneumatic weight-simulators. The only color in the chamber came from the screens of the data desks, and from the slice of Jovian cloud visible through the dome.

Serena Milpitas strolled toward Louise, her footsteps clicking loudly on the hard floor. She ran a fingertip along the surface of a data desk. “It’s a high quality Virtual projection, with semisentient surface backup,” she said. “Feel it.”

“I don’t need to,” Louise groused. “I’m sure it is. That’s not the bloody point. This is obviously meant to be the life-dome of a GUTship — a small, limited, primitive design compared to my Northern, but a GUTship nevertheless. And — ”

Light, electric-blue, flooded the dome. The explosion of brilliance was overwhelming, drenching; Louise couldn’t help but cower. Her own shadow — sharp, black, utterly artificial — seemed to peer up at her, mocking her.

She lifted her head. Beyond the transparent dome above her, an artifact — a tetrahedron glowing sky-blue — sailed past the limb of the Jovian planet. It was a framework of glowing rods: at first sight the framework looked open, but Louise could make out glimmers of elusive, brown-gold membranes of light stretched across the open faces. Those membranes held tantalizing images of starfields, of suns that had never shone over Jupiter.