“Never is a long time. Why do you think it’s one of a kind?”
“Judge for yourself when we get there. Regulo found this about thirty-five years ago, when they were doing his first complete survey of the Belt. Nobody else realized the significance of the find, so he got the rights to it for almost nothing. Most people thought it was useless — who could use something with that composition? All the outside was water ice, more than you’d ever need for the volatiles of an orbit adjustment. There was a lump of metallic ores — very pure — sitting right in the middle, but it would be difficult to reach.”
“You mean it wouldn’t pay to tunnel in and mine it? I suppose not. There are plenty of other candidates around, with more ore and less water.”
“That’s what the other miners decided. But after he bought long-term rights, Regulo coated the outside with a black hi-temp plastic, started it rotating, and dropped it into a tight hyperbolic. Then he picked it up on the other side, once it was well clear of the Sun.”
Rob was busy at the calculator interface. After a few seconds he looked up and shook his head. “It wouldn’t work, according to me. You’d never melt it with a single fly-by.”
“Did I say that? He had his team pick it up near Mercury and put it into a Trojan orbit with the planet. He wouldn’t go near it himself, of course, not that close to the Sun. While the meltdown was going on he had a mining group confirm the first assay of the ores and do the core analysis in more detail. That became a lot easier after partial melt. It took five years to complete the change from ice to water, then they used some water in the drives to take it further out. Regulo met them near Earth and started the installation of the hydroponics systems. By that time, some of the others had begun to get an idea what he was doing.”
“And now he has it self-supporting?”
“Completely. Regulo says that with a few months’ warning Atlantis could survive if Sol went nova. He’d simply move the whole thing out to a safe range from the Sun.”
“But he’s exaggerating.”
“Of course he is.” Corrie laughed, throwing her head back. As she did so. Rob was distracted by her sudden resemblance to Senta Plessey. Would he be able to help Howard Anson with Senta, after this trip to Atlantis?
“But he’s entitled to exaggerate a bit,” Corrie went on, and Rob pulled his attention back to her. “He’s rather proud of that job,” she said. “He claims that he’s the only person in the whole System who would have thought of it.”
She looked at Rob, head cocked to one side. “You know, you two are alike in another way. Each of you is convinced that he’s the only smart person in the System.”
“Universe. Whereas?”
“Whereas Caliban is a lot smarter than both of you put together.” Corrie was laughing. “Smarter than Joseph Morel, too.”
“Caliban? Who the devil is Caliban?”
“You mean Regulo hasn’t told you? Then you have another treat coming. Just wait and see.”
She was in an unusually cheerful and fickle mood. That was all the response that Rob could get. She replied to all his questions with cryptic, evasive answers, while the cruiser bore them steadily closer to Atlantis.
Rob remained peering into the scope, seeking more details of the mystery asteroid ahead. Following Regulo’s work, it had become a sphere of water rather less than two kilometers across. It was surrounded by a restraining membrane of tough flexible plastic, a trapping surface for solar heat. The aquasphere was pierced by twenty metal-lined shafts that served as structural braces and also provided access from the exterior of the asteroid to the central metal sphere where living quarters and laboratories were located. Other entry to the two-hundred-meter central biosphere came from the ports that connected the living quarters to the aquasphere. As they drew closer, Rob could see the silver gleam of heavy drive equipment positioned near the outer edge of each entry shaft. The whole ponderous assembly was rotating slowly about its center of mass. Small attitude jets positioned at a number of points on the surface showed how the rotation rate was controlled.
“I thought you were just joking about getting away from a nova,” said Rob. “Now, I’m not so sure. There are drives all over that thing and they look like big ones. Do you know what sort of acceleration he can get on it?”
Corrie was busy at the communicator, tuning in for their final arrival. “Not much at all,” she said. “There’s plenty of power, but the limiting factor is the strength of the support shafts and the surface membrane around the aquasphere. They take the main stresses when Atlantis is accelerated. The interior is nearly all liquid water, even allowing for the support shafts and interior structures. You need monster drives for any acceleration worth speaking of, because Atlantis masses about four billion tons. That takes some shifting. Regulo usually doesn’t try for more than a hundredth of a gee. He gets around, but it takes a while.”
They were creeping closer to one of the entry shafts, their angular rate matching to that of the asteroid. Close up, the surface had a dull, smooth finish, making Atlantis visible only as a black mass occulting the bright star field behind it.
“No wonder I couldn’t pick it up on the screen,” said Rob. “The surface is sitting there in full sunlight but there’s no radiation back-scatter at all. At least, there’s not enough to see.”
“There should be hardly anything at visible wavelengths.” Corrie was sitting next to him as they awaited final docking. “Morel designed it that way. The aquasphere has been made into a self-sustaining community of plants and animals. It uses all the light that it can get for photosynthesis. That’s why Regulo and Morel covered it with variable albedo materials. Nothing is reflected as visible light, and all the heat goes out through the side facing away from the Sun.”
“Sounds like a violation of the Second Law of Thermodynamics to me.” Rob was impatiently peering out of the side port, waiting for a glimpse of the interior. “You’re telling me I won’t be able to see anything at all from out here, then?”
“That’s right. Wait until we get inside, then you’ll see plenty. You can even take a swim through the interior if you want to.” She grinned at some secret joke. “I somehow doubt that you will. I certainly never have. I should have warned you of one other thing: be prepared for a fishy dinner. Regulo imports food when he feels like it, but he makes the point to new arrivals that he has a completely closed ecology operating in Atlantis. The human living quarters in the center are part of the overall balance, with reprocessed wastes going back into the aquasphere as nutrients. Of course, you lose a little mass when you move around the System, but Regulo replaces that occasionally from other asteroids.”
“Does Atlantis have any internal power sources? Big ones, I mean, to provide power and light.”
“There are a couple of fusion plants, and Regulo talks of adding a power kernel. Why?”
“I was thinking of your statement that Regulo hates the Sun. With this set-up, he’s independent of it. He could provide the light for photosynthesis in the aquasphere from his own power sources, and if he did that he could go as far away from the center of the System as he chose — out beyond the Halo, if he feels like it.”
“He’s talked of it; but he likes to know what research is going on, in the Belt and back on Earth. If it weren’t for that, I think he might take Atlantis a long way out. Maybe leave the System completely.” There was a slight bump, felt through the floor of the ship. “Feel that? We’re docked. We can go inside now. Regulo doesn’t believe in elaborate entry procedures. Anybody that he doesn’t want in Atlantis would never get this far. His computers will have checked the signature of this ship against the System ship listings when we were still a hundred thousand kilometers out.”