Her face had a damp, suffocated look, as if being in the s.p.a.cesuit made her claustrophobic. "Let's go," she said.

I unclutched the tracks and set off, lurch of the cabin throwing her against my shoulder, felt her brace herself, keeping what distance she could, not much in this little s.p.a.ce. How much of what I'm feeling is fossil emotion, old subroutines frozen in my head?

I don't know what I want because I'm afraid, is that it?

I said, "Christie? When are you going to tell me what's going on?"

When I turned my head to look, her face was no more than a hand's breadth away, but facing forward, eyes not blinking as she watched familiar t.i.tanscape come and go. Overhead, from down in the bottom lands, the eclipsed sky was the color of a fresh bruise, blue and gray, dull purple, tinted with vague streamers of magenta.

Then she turned her head toward me, eyes on mine. That brought her close enough we were breathing on each other. You know how that goes. You get in each other's facial s.p.a.ce and there's tension there, because the next move is that forward craning, that...

She looked away again, not outside, just at the inner surface of the wall, at a circuit breaker panel mounted about eye level. "Did you tell anyone else?"

I shrugged. "Nothing to tell, I guess."

No answer. Tension in the arch of her neck. I wanted to reach out and touch her, tell her some nonsense about how it'd be all right. Then, with my arm around her, with her s.p.a.ce invaded... there's something about the vulnerability of fear, about there being some terrible thing wrong.

She said, "Pull up here. Let's get out."

We'd come to the cliffs by the beach, but were still some distance from the familiar way down, rolling one at a time out the lock, then following my earlier tracks to the place where I'd spied on her before. They'd been joined by numerous other footprints now, hundreds coming and going.

All hers, I guess.

There was a thin wisp of black smoke rising above the instrument package, like an elongated drop of india ink in clear water, rolling with the convection currents, just beginning to dissipate.

And, all around it on the beach, were swipes and smears of color, shades and shapes moving round and round, all so very slowly. As I watched, a dark blue one came close, stretching out a long, narrow pseudopod. It came within a few centimeters of one support leg, hesitated for a moment, then touched.

The pseudopod shriveled, shrinking quickly back toward the main body, which seemed to roll over, turning to a lighter shade of blue, then sinking into the beach, gone in an instant.

There was another black curl in the air, rising above the instrument package, drifting slowly away as it dissipated. I thought of the sample I'd taken of that earlier instrument contamination, presumably still in the halftrack refrigerator where I'd left it.

Little beasties investigating the alien machine. Innocent little beasties getting themselves killed.

Is curiosity just a tropism?

Moths to the flame.

I said, "I guess that makes your case, hm?"

I don't know what I expected next, but she said, "Turn off your radio now."

"Um..."

She turned and put her hand on my arm. I couldn't feel it through the suit material, but those big eyes, begging... I switched it off and waited. She just turned away, quickly stepping to the edge of the cliff, dangerously close given the fragility of this chemical ice, and pulsed the carrier wave power setting of her suit's comm system, one, two, three, off.

All very much like in a movie.

Down on the beach, the waxthings froze in place, a conscious freezing, just the way a spider will freeze the instant it realizes you're looking. That sudden crouch, alien eyes pointing your way, spider brain filled with unknowable thoughts.

I remembered the way one of these things had grown a speckle of orange dots before and recalled a science film I'd seen as a kid, high speed photography of slime molds in action. Eerie. Not more so than this.

Suddenly, between one frame and the next, the beach was empty.

In all those old movies, old stories, they get the feeling of this moment terribly wrong, don't they? I reached for my comm controls, but Christie, catching my movement from the corner of one eye, raised a restraining hand.

Wait.

I...

Down on the beach, a flat, ragged-edged plain of blue formed. Time for a few heartbeats, then a sharp-edged stripe of pink slid across the side of the plain nearest our vantage point.

Then a conical shape slid into view from the other side, visibly falling toward the pink.

Falling.

Just before it hit, there was a reddish-orange swirl under the blunt side of the cone. It slowed to a stop, popping out little landing legs, flame gouting on the surface, then winking out.

Little blue and green dots appeared, embedded in the pink, drawing in toward the motionless cone. As they drew close, one by one, they would turn black and vanish. After a while, you could see they'd learned to keep their distance, hovering around the edge of the picture.

My mouth was dry as I switched on my radio and whispered, "How the h.e.l.l do they know what our sense of perspective is like?"

Whispered, as though someone might be listening. Some thing.

Her voice was hardly more than a breath, blowing through my earphones: "They're not really two dimensional creatures."

It's not Flatland. They're not waxy paintings on the surface of the ground.

Fire blossomed under the cone and it lifted off, climbing out of the picture, and all the remaining blue dots turned black before vanishing.

After a while, more of them crept from the edge of the picture, creeping through the pink toward the place where the cone had been. At first, the leaders turned black and died, but only for a little while. In time, they finished their investigations, then went sliding on their way.

The blue plain with its empty pink strip vanished suddenly, and the beach was empty again.

I turned to her and said, "Why'd you show me this?"

Seen through the faceplate, she was nothing but eyes. Big blue eyes. Serious. Frightened. "I won't make this decision by myself. I'm not..." Long hesitation. "You know."

Yeah. Not G.o.d. That's how that one goes.

Back at the habitat, after a long, silent ride, we sat together in our longjohns, made tea and drank it, made small talk that went nowhere, circling round and round, as if something had changed, or nothing.

We're dead men here, I'd thought on the way back, watching a snowdrift blow across the beaten path before the halftrack, slowing down as if to stop, then suddenly lifting off in the wind like a flock of birds making for the sky, clearing the way for us.

Fewer than two thousand survivors...

In the old stories, old movies, that would've been more than enough, two thousand hot, eager Adams and Eves, getting about their delving and spanning, wandering the freshly butchered landscape, pausing by the sh.o.r.es of an infinite, empty sea, being fruitful, multiplying until they'd covered the Earth again.

This star system no longer contains an inhabitable planet.

Bits of memory, s.n.a.t.c.hes of Moonbase newsreel. When Oberth gets home with the crew of the Venus...o...b..tal station, who hadn't had to commit suicide, she'll be bringing a stockpile of hardened probes intended for research on the surface of Venus.

Hardened probes, and, of course, one of the piloted Venus landers.

Then we'll know for sure. Then we'll...

Couldn't stop myself from imagining, ever so briefly, myself on that first d.a.m.ned crew, riding the Venus lander down through howling brown muck, down to a soft landing in my own backyard.

I've been on Venus. I'm qualified for Venus EVA ops. I...

Read a science article when I was a kid that described the Chicxulub impact at the KT Boundary as being "like taking a blowtorch to western North America."

The image in my head was a double exposure, the image of collapsed and burned-out cities, like something from an atomic war fantasy, superimposed over the reality of a cooling lava ejecta blanket.

Just wisps of smoke.

That's all that's left of her.

Christie, face pushed down in the steam from her teacup, was looking at me strangely. G.o.d knows what my expression must have been like. Did you have anyone, Christie Meitner, or was it only strangers that died? Billions and billions of strangers.

She said, "I guess we'd better talk about it now." Unsaid, Whether we want to or not.

I nodded, not knowing what I wanted, looking into a face that wasn't all that expressive. A face not so different from my own. I tried to remember what I looked like, call up the man in the mirror, but there was only fog, no way to know what she was looking at now with those big, hollow eyes.

She said, "It's so simple, Hoxha: They're alive, and this is their world. If we stay here, even just the few score of us, t.i.tan's environment will slowly change, until this is no longer an inhabitable world for them."

And then?

Right.

"Does it make a difference now that we know they're intelligent?"

She shook her head. "If we work together to keep it secret, to keep the others from stumbling over this, once we go away, back to Moonbase..."

I said, "The Earth's not going to recover and we can't survive forever at Moonbase. The Saturn system's our best bet, otherwise we're spread too thin. Even Mars..."

She said, "The odds are against us, no matter what."

I nodded.

"So we come here, obliterate the t.i.tanians, and then die out anyway, erasing their future as well as ours."

Does this mean anything? What's my next line? I know: Christie, this is proof positive life is common in the universe. Right. Idiot. I remember the way she'd looked, face so pale, eyes so big, standing behind me with the ice axe, willing herself to kill. How many t.i.tanians would've exploded and burned under the beach had my blood been spilled?

I said, "So that's what all this is about? Some good old-fashioned eco..." Right. Like the idiots who protested Ca.s.sini's launch all those years ago, while not doing a d.a.m.ned thing about the world's hundred thousand hydrogen bombs.

Pick your targets. Some are easier than others.

She seemed tired. "It's not just that. If it was just about them being living things, intelligent living things, you wouldn't be sitting here now."

"Dead and buried?" I smiled. "That would've been hard for you to explain."

"I wasn't thinking clearly. I was panicked that you'd..."

"What, then? Why am I still here?"

Long, long stare, still trying to fathom if there was a human being behind my face, someone just like her. She said, "Day before yesterday, I found evidence that their life process involves some kind of directed nucleosynthesis."

You could see the relief in her face. There. I've said it. And...

Nucleosynthesis?

Talking about details is what we're doing.

In those old stories, old movies, the details are always important, imaginary science chatted up by happy, competent characters until G.o.d springs from the machine and utters his funny-elf punchline.

Now?

Not important.

Not anymore.

And yet...

I said, "That could tip the scales in our favor. We come here, we learn to exploit them, we survive as a species."

Her face fell.

I don't think she expected me to see it that easily.

Probably there was a scenario in there in which the pedantic teacher explains things to the gaping mechanic in the simplest possible terms. That's the story way, isn't it?

She sat back in her chair and sighed. "I don't know what we should do. Do you?"

People love to pretend they make rational decisions. It's called excuse-seeking behavior. Christie and I sat facing one another for a long time, tension making it seem we were about to speak, but we never did. You want to be the first one to start offering up excuses? No, not me. How about you? If it was important enough to reach for that axe, surely...

I wasn't thinking clearly.

Right.

So we talked about the evidence, which she explained to me in the simplest possible terms, until I was able to pick up the thread and begin spooling it into my own knowledge base, understanding it in my own terms. Understanding. That's an important part of making excuses for what you do, isn't it?

Or what you fail to do.

Think about the possibilities, Christie.

Think about the technology we could build here. Think of the resource base. And the t.i.tanians? Is it important what happens to them?