Iris

down with the engines flaming. On H2vent-thrust only, I guess, we could . . .' Krzakwa cut him off. 'I've been thinking about it,' he said.

'How does this sound: we suit up, eliminate radiation from the worksuits, and jump . . .' Sealock suddenly stopped moving, staring into dead space for a second, then he turned to look at the Selenite again, his eyes seeming to glow. 'You son of a bitch. Sure! Like that boil-gliding business ...' His imagination chewed at the details of the notion: 'I'll put her in a low orbit, maybe half a kilometer up. The jump won't kill us. We use pressurized O2from our life-support systems like jets to get back.' He sat back in his couch, gloating to himself. 'And we make a suit-instrumented rendezvous with Polaris at the end of it all. . . . Hell, this is really going to be fun!'

Aello spun underneath them as Brendan maneuvered the ship down into an orbit so low that they could make out the unmistakable shadow of the craft near the huge, uneven horizon. Even with the weak gravity, this deep in her gravity well Aello effectively swept them along, and the wells of shadow that were craters moved under them quickly. Brendan was fully engrossed in his piloting, plugged into systems that effectively made him an incredibly sensitive receptor. He rushed along, sensing his passage with radar, and could feel the gravitational anomalies caused by variations in the moon's shape and constituents as a series of small velocity changes. He cataloged them as he flew, feeding data to the calculations that Krzakwa was making, fine-tuning their notions about how the orbit of the ship would precess while they were down on the moon. They needed to know. As he delved deeper into the substance of the world, reading it carefully, all the while avoiding an intense radiation flux that would disturb sensitive materials, his eyes became totally blind to the bottomless craters that were calling forth the nightside.

He was just about to disconnect from his systems, in preparation for going down, when something in the residuals of the newest ship computational ephemeris caught his attention. He checked a map and saw that they were passing over the very center of Sayyarrin. This is some kind of a weird little anomaly, all right, he thought. Really weird . . .

'Tem,' he said, 'are you monitoring the external sensor returns?'

'Uh-huh,' said Krzakwa, 'what is it?'

'You're the physicist, buddy, you tell me.'

Tem studied the figures of the ephemeris in his head, brought in a calc overlay, and spent a full minute processing. Finally he said. 'I think we must've put one of our machines together backward. It's a glitch.'

'Oh, yeah? OK. Here's an updated computation, seven seconds old. If that's a glitch it's got a sense of humor.'

' Materi bogu!There's some kind of void down there, under the ice.'

'Impossible. It's not a void, it's a shell of some kind. A thin layer of mass around an almost massless core. Now what in the fuck could cause that?'

'Speculation, you mean? Some kind of hollow meteorite?' As he said it, he realized how unlikely a thing that was. It could happen, yes, but on this scale?

Sealock said: 'But look at the size, the dimensions. This is not exactly a high-resolution picture—but even the parameters of the orbit suggest something more like ...'

Krzakwa shook his head. This was ridiculous. There were explanations. Besides . . . 'There's nothing in the view that suggests anything unusual. There are volcanic chambers all over the outer Solar System.' He marked the spot, now rapidly disappearing behind them, with a bright optical V. In the deep IR

they could see the low rim of Sayyarrin and its rather smooth floor. Perhaps it was just a tiny bit darker, colder, than its surroundings: a dim shape under the ice. Then it was gone over the horizon. Brendan violently spun Polaris around, inertia tugging at their bodies, and lit off the engine. The craters slowed, stopped, and the bright line that was day receded back behind the world. Sayyarrin popped over the horizon and, when they were directly over it, Sealock repeated his action, this time slowing the ship to a dead halt over the center of the crater. Tem could only tell from his instruments that they were falling, gently, toward the ice less than half a kilometer below. Brendan turned up the gain on the photochip , isolated a narrow region in the far infrared that would best define the heat differences they had seen, and, yes, there it was.

He pushed the ship back into an orbit, paying little attention to its parameters. When they were flying above the ice once more he turned to look at the Selenite. 'So. You're saying Sayyarrin is a caldera?' He called up some imagery from the Shipnet element and its source files, staring so hard into the image in his brain that he squinted malevolently. 'That sort of contradicts the picture you were drawing before.' Krzakwa nodded slowly. That was the way it seemed, but . . . Damn it, there had to be some kind of reasonable explanation. 'I don't know. Day comes in about three hours. It will take about half an hour to suit up. I say we get Polaris back in the right orbit and go down in the suits. There really is no telling what will happen if we try to land in that stuff. It might be the most effective way to reach the lower stratum—but the ship could easily be damaged by the violent sublimation, even in this paltry gravity.' Brendan seemed to pull back into himself somewhat. 'Mmm. Yeah. We turn up the heat of our suits and fall through the neon. Any turbulence that creates, we can certainly deal with. OK—full speed ahead.'

Downlink Rapport wasn't getting any easier. Insofar as the thoughts and feelings of John and Beth were couched in linguistic or sensory terms, the transfer was without effort. But underlying personal emotions and states of being were more difficult, flooding into the brain as strange, ephemeral data. Understanding required a great deal of work. Memories were a lingua franca between them, perhaps because, even in an individual, memories come from somewhere far off, separate from the 'self.' It was easiest to tap into the full experience of being another person through the facility of the past. It came: they were annoyed. No matter what subject John tried to initiate, Beth would turn it aside. In bed, back in her condo in Yellowknife after a long winter walk through the streets, their