The universe is all extremes. Monstrous gravity fields, or next-to-nothing ones; extreme cold, or heat so intense that solids and liquids cannot exist; multimillion atmosphere pressures, or near-vacuum.

Ice or fire. Niflheim or Muspelheim: the ancient alternatives, imagined by humans long before the Expansion.

It’s planets that are the oddities, the strange neutral zone between suns and space, the thin interface where moderate temperatures and pressures and gravity fields can exist. And if planets are anomalies, then planets able to support life are rarer yet — a zero-measure subset in that set of strangeness.

And within that alien totality, where do humans fit?

“Willing to share your thoughts?” Hans Rebka’s voice interrupted Darya’s bleak musings.

She smiled but did not speak. She had been gazing out of the port of the Summer Dreamboat, her head filled with the unsatisfying present and the far-off dreams of Sentinel Gate. She was 800 light-years from home. Instead of the Sentinel, Gargantua filled the sky, as big as at Summertide and far more dominant. The Eye was a smoky whirlpool of gases, wide enough to swallow a dozen human worlds.

“You want me to help you?” she asked.

“You couldn’t if you wanted to.” Hans Rebka jerked his head toward the control panel. “They won’t let me get near it. I think Kallik’s having fun.”

It was nice to know that someone was. The arrival in orbit around Gargantua had depressed Darya enormously — to come so far, with such vague goals, and then find nothing toward which she could point and say, “There! That’s it. That’s just what I hoped we’d find here.”

Instead they had found what she should have expected. A planet, big enough to be at the fusion threshold, unapproachable by humans because of its dense, poisonous atmosphere and giant gravity field. Dancing attendance on Gargantua were its four major satellites, with their own atmospheres and oceans; but the air was mostly nitrogen, plus an acrid photochemical smog of ethane and hydrogen cyanide, and the oceans were liquid ethane and methane. The surfaces, recently heated by close approach to Mandel and Amaranth, were dropping back to a couple of hundred degrees below freezing.

If they were to find anything, the best bet was on one of the hundreds of smaller, airless satellites. Kallik and J’merlia were patiently identifying those, tagging each with its own set of orbital elements for future identification; the intertwining orbits were impossible to follow by eye, and a tough job even for the Dreamboat’s computer. Finally the team would examine “anything interesting,” which was the vague criterion that Darya had provided.

“How many have they done?” Darya was not too sure she wanted to hear the answer. Because when they had worked their way through all the larger fragments she had no suggestion as to what they should do next, beyond the bitter option of an empty-hands return to Dobelle.

Hans Rebka shrugged, but J’merlia had heard the question. The lemon eyes turned on their short eyestalks. “Forty-eight.”

He went on to answer the unasked question. “At this time, we have found nothing. Not even a prospect of high-value mineral deposits.”

Of course not. Don’t be so dumb, J’merlia. This is part of the Phemus Circle, remember? Metal-poor and mineral-poor and everything-poor. The whole Mandel system had been scoured for metals and minerals back when it was first colonized. If anything had been out here it would have been mined and picked clean centuries ago.

Darya managed not to say all that. She realized that she was angry with everything. She began to feel guilty. The two aliens were doing all the work, while she sat back, watched, and complained. “How many still to go, J’merlia?”

“Hundreds, at least. Every time we look more closely we find more small bodies. And each one is a time-consuming task. The problem is the orbital elements — we need many minutes of observation before we can assign them accurately. And we need accuracy, because the fragments move. We have to be sure we are not missing one, or doing some of them twice. The old catalogs help, but the recent perturbations make them unreliable.”

“Them we’ll probably be sitting here for a long time — at least a few days. What do you think, Hans? Maybe it’s time to pick one of the planetoids, somewhere we can spread ourselves a bit until the search is over. We’ve got suits with us; at least we can stretch our legs and get out of each other’s hair for an hour or two.”

“We already have a… ck-candidate for such a place.” Kallik had also been listening and watching. Her command of human speech was approaching perfection, but it could still betray her occasionally in moments of excitement. “We noted it when we first… ss-saw it. J’merlia?”

The Lo’tfian nodded. “It was already in the old catalog. It carries an identification as Dreyfus-27, and at one time a survey expedition used it as a base of operations. There should be tunneling, perhaps an airtight chamber. It can be reached from our present orbit with a minimal energy expenditure. Would you like to see its stored description?”

Darya had accepted J’merlia’s suggestion with indecent haste. She knew that, but she didn’t regret it. Motion, bustle, activity, that was what she needed at the moment — even if it was only motion and bustle, something as useless as fixing up a barren lump of rock so that humans and aliens might call it home for a few days.

Close approach to Dreyfus-27 had confirmed the data suggested by the Summer Dreamboat’s remote sensors. The planetoid was a dark, craterd body only ten kilometers in diameter, swinging in low orbit around Gargantua. A thousand years before, traces of nickel and iron in the outer layers of Dreyfus-27 had encouraged prospectors to drill the interior. The rubble and tailings that still formed a meters-deep coat to the planetoid’s rugged surface showed that no deposits worth refining had been found, but the automated drilling equipment of the miners had not given up easily. Dreyfus-27 had been tunneled and retunneled, carved and bored and fractured and drilled until dozens of crisscrossing shafts and corridors and chambers riddled the inside.

Without air and appreciable gravity, those tunnels had not changed since the day they had been abandoned. The new arrivals could read the final frustration of the miners in the jumbled heaps of debris and half-completed living quarters. The prospectors had started out with high hopes, enough for them to plan a permanent base appropriate to extended mining operations. Those hopes had slowly evaporated. One day they had just downed tools and left. But although they had stopped halfway in making Dreyfus-27 fully habitable, their efforts were more than enough for the short-term needs of the crew of the Dreamboat.

“Seal it at the top, and this will do,” Darya said. She and J’merlia had found an almost empty cylindrical chamber with a narrow entrance, five meters below the surface, and had tested the walls to make sure that they could hold the pressure of an atmosphere. “The thermal insulation is as good as the day it was installed. Let’s go back up. Once we pump some air in here we can open our suits. That will be wonderful.”

She looked around her. The chamber was clear of major rock fragments, but powdery grit covered the passivine wall lining and flew up at every contact and vibration.

Wonderful? she thought. My God, I’m slipping down the ladder, rung by rung. A couple of months ago I’d have been appalled at the idea of spending ten minutes in a place like this. Now I can hardly wait to settle in.

J’merlia was already at home. The Lo’tfians were a burrow race, and the land surface of their home planet formed one vast, interconnected warren. He had been scuttling excitedly from one chamber and corridor to the next. Now he nodded his head and led the way back up the weak gravity gradient.