Things began to shape up. But it was a long time before he and Peter took off in a space plane again. This time they rocketed out of the stratosphere entirely, and then far above it. Twenty thousand kilometers above it, until they were closing on Deimos. And then making a rendezvous with it.

The gravity of the little moon was so slight that it was more a docking than a touchdown. Jackie Boone, who had helped on the project, mostly to be close to Peter (the shape was clear), guided the plane in. As they approached, Sax had an excellent view through the cockpit window. Deimos’s black surface looked to be covered by a thick coat of dusty regolith — all the craters were nearly buried in it, their rims soft round dimples in the blanket of dust. The little oblong moon was not regular, but was rather composed of several rounded facets. A triaxial ellipsoid, almost. An old robot lander sat near the middle of Voltaire Crater, its landing pads buried, its coppery articulated struts and boxes dimmed by a fine dark dust.

They had chosen their own landing site on one of the ridges between facets, where lighter bare rock protruded from the blanket of dust. The ridges were old spallation scars, marking where early impacts had knapped pieces of the moonlet away. Jackie brought them down gently toward a ridge to the west of Swift and Voltaire craters. Deimos was tidally fixed, as Phobos had been, which was convenient for their project. The sub-Mars point served as 0° for both longitude and latitude, a most sensible plan. Their touchdown ridge was near the equator, at 90° longitude. About a ten-kilometer walk from the sub-Mars point.

As they approached the ridge, the rim of Voltaire disappeared under the black curved horizon. Dust blew away from the ridge as the plane’s rockets shot exhaust over it. There was only a few centimeters of dust covering the bedrock. Carbonaceous chondrite, five billion years old. They docked with a hard thump, bounced away, slowly drifted down again. He could feel the pull toward the floor of the plane, but it was very slight. Probably he didn’t weigh more than a couple of kilograms, if that.

Other rockets began to land on the ridge to either side of them, kicking clouds of dust into the vacuum, where they drifted slowly down. All the planes bounced on impact, then came down gently through their dustclouds. Within half an hour there were eight planes lined up on the ridge, running along it to the tight horizons in both directions. Together they made a weird sight, the inter-metallic compounds of their rounded surfaces gleaming like chitin under the surgical glare of unfiltered sunlight, the clarity of the vacuum making all their edges overfocused. Dreamlike.

Each plane carried a component of the system. Robot drillers and tunnelers and stamps. Water-collection galleries, there to melt the veins of ice in Deimos. A processing plant to separate out heavy water, about one part in 6,000 of the ordinary water. Another plant to process deuterium from the heavy water. A small tokamak, to be powered by a deuterium-deuterium fusion reaction. Lastly guidance jets, though most of these were in planes that had landed on the other sides of the moon.

The Bogdanovist technicians who had come up with the equipment were doing most of the installation. Sax got suited up in one of the bulky pressure suits on board, and went out the lock and onto the surface, thinking to look and see if the plane carrying the guidance jet for the Swift-Voltaire region had landed.

The big heated boots were weighted, and he was glad of it; escape velocity was no more than twenty-five kilometers an hour, meaning that with a running start one could jump right off the moon. It was quite difficult to keep his balance. Millions of tiny motions carried one along. Every step kicked up a healthy cloud of black dust, which slowly fell to the ground. There were rocks scattered on top of the dust, usually in little pockets they had made on landing. Ejecta which had no doubt circled the moonlet many times after ejection, before dropping in again. He picked up one rock like a black baseball. Throw it at the right speed, turn around, wait for it to go around the world, catch it chest high. Out at first. A new sport.

The horizon was only a few hundred meters away, and it changed markedly with every step — crater rims, spallation ridges, and boulders popping up over the dusty edge as he trudged toward it. People back on the ridge, between the planes, already stood at a different upright than he did, and were tilted away from him. Like the Little Prince. The clarity was starting. His footprints made a deep trail through the dust. The dustclouds hanging over the footprints got lower the farther back they were, until they settled, four or five steps back.

Peter came out of the lock and walked in his direction, and Jackie followed. Peter was the only man Sax had ever seen Jackie really attracted to, in that intense helpless manner of the orbiting object, the lovelorn, yearning for orbital decay. Peter was also the only man Sax had ever seen who did not respond to Jackie’s amorous attentions in any way. The perversity of the heart. As in his attraction to Phyllis, a woman he had not liked. Or as in his desire for the approval of Ann, a woman who had not liked him. A woman with crazy views. But perhaps there was a rationality to it. If someone moons over you, you have to wonder at their judgment. Something like that.

Now Jackie trailed Peter like a dog, and though their faceplates were a copper color, Sax could tell just by her movements that she was talking to him, cajoling him somehow. Sax turned to the common band and came in on their conversation.

“ — why they’re named Swift and Voltaire,” Jackie said.

“Both of them predicted the existence of the Martian moons,” Peter said, “in books they wrote a century before the moons were seen. In Gulliver’s Travels Swift even gives their distances from the planet and their orbit times, and he wasn’t that far off.”

“You’re kidding!”

“No.”

“How in the world did he do that?”

“I don’t know. Blind luck, I guess.”

Sax cleared his throat. “Sequence.”

“What?” they said.

“Venus had no moon, Earth one, Jupiter four. Mars should have had two. Since they couldn’t see them, they were probably small. And-close. Therefore fast.”

Peter laughed. “Swift must have been a smart man.”

“Or his source. But it was still blind luck. The sequence being a coincidence.”

They stopped on another spallation ridge, from which they could see the rim of Swift Crater, as a nearly buried ridge on the next horizon. A small gray rocket plane stood on the black dust like a miracle. Above them Mars filled most of the sky, a vast orange world. Night was falling across the eastern crescent. Isidis was directly above them, and though he could not make out Burroughs, the plains to the north of it were patched with great white splotches. Glaciers meeting up to become ice lakes, and the beginnings of an ice sea. Oceanus Borealis. A corrugated layer of clouds lay pasted right against the land, reminding him suddenly of what Earth had looked like from the Ares. That was a cold front, coming down Syrtis Major. The pattern of white clouds was just what it would have been on Terra. Spiraling waves of condensation particles.

He left the ridge, walked back toward the planes. The tall stiff boots were the only things that kept him upright, and his ankles hurt. Like walking on the sea bottom, only with no resistances. Universe ocean. He reached down and dug in the dust; no bedrock for ten centimeters, then twenty; it could have been five or ten meters deep, or even more. The dustclouds he had kicked up dropped back to the surface in about fifteen seconds. The dust was so fine that in any kind of atmosphere they might have stayed in suspension indefinitely. But in the vacuum they fell like anything else. Ejecta. There simply wasn’t much to pull them back. One might be able to kick dust into space. He crossed a low ridge and abruptly could see over the sloping plain of the next facet. It was so obvious that the moonlet was shaped like some paleolithic hand tool, with facets knapped off by ancient strikes. Triaxial ellipsoid. Curious that it had such a circular orbit, one of the most circular in all the solar system. Not what you would expect of a captured asteroid, nor of ejecta flung up from Mars in one of the big impacts. Leaving what? Very old capture. With other bodies in other orbits, to regularize it. Knapp, knapp. Spall. Spallation. Language was so beautiful. Rocks striking rocks, in the ocean of space. Knocking bits off and flying away. Until they all either fell into the planet or skittered off. All but two. Two out of billions. Moon bomb. Gun stand. Rotating just faster than Mars above, so that any point on the Martian surface had it in the sky for sixty hours at a time. Convenient. The known was more dangerous than the unknown. No matter what Michel said. Clomp, clomp, on the virgin rock, of a virgin moon, with a virgin mind. The Little Prince. The planes rising over the horizon looked absurd, like insects from a dream, chitinous, articulated, colorful, tiny in the starry black, on the dust-blanketed rock. He climbed back into the lock.