Stephen Baxter: Xeelee: Endurance

We got there first, and we squatted around the downed spider in a splash of suit light. The spider hadn’t broken open; it was not enclosed by a hull or external carapace. Instead it had shattered into pieces, like a smashed sculpture. We pawed at the debris chunks, Miriam and Poole talking fast, analysing, speculating. The chunks appeared to be mostly water ice, though Poole speculated it was a particular high-pressure form. The internal structure was not simple; it reminded me of a honeycomb, sharp-edged chambers whose walls enclosed smaller clusters of chambers and voids, on down through the length scales like a fractal. Poole pointed out threads of silver and a coppery colour – the shades were uncertain in Titan’s light. They were clearly metallic.

The other spiders closed in on the corpse. Wary of getting chomped by accident we backed off, dimming our suit lights.

Miriam asked, ‘So, biological or artificial? What do you think?’

Poole shrugged. ‘They seem dedicated to a single purpose, and have metallic components. That suggests artificial. But that body interior looks organic. Grown.’

I felt like putting Poole in his place. ‘Maybe these creatures transcend your simple-minded categories. Perhaps they are the result of a million years of machine evolution. Or the result of a long symbiosis between animal and technology.’

Poole shook his head. ‘My money’s on biology. Given enough time, necessity and selection can achieve remarkable things.’

Miriam said, ‘But why would their systems incorporate metal if it’s so rare here?’

‘Maybe they’re not native to Titan,’ I said. ‘Maybe they didn’t evolve here.’ But they weren’t listening to me. And besides, they didn’t want to hear any kind of theory that implied sentience. ‘The real question is,’ I said more urgently, ‘what do we do now?’

The head of Harry Poole, projected somehow by our suit’s comms systems, once more popped into existence, the size of an orange, floating in the air. The small scale made his skin look even more unnaturally smooth. ‘And that,’ he said, ‘is the first intelligent question you’ve asked since we press-ganged you, Jovik. You ready to talk to me now?’

Michael Poole glared at his father, then turned and sucked water from the spigot inside his helmet. ‘Tell us how bad it is, Harry.’

‘I can’t retrieve you for seven days,’ Harry said.

I felt colder than Titan. ‘But the suits—’

‘Without recharge our suits will expire in three days,’ Poole said. ‘Four at the most.’

I could think of nothing to say.

Harry looked around at us, his disembodied head spinning eerily. ‘There are options.’

‘Go on,’ Poole said.

‘You could immerse yourselves in the crater lake. The suits could withstand that. It’s cold in there, the briny stuff is well below freezing, but it’s not as cold as the open air. Kept warm by the residual heat of impact, remember. Even so you would only stretch out your time by a day or two.’

‘Not enough,’ Miriam said. ‘And we wouldn’t get any work done, floating around in the dark in a lake.’

I laughed at her. ‘Work? Who cares about work now?’

Poole said, ‘What else, Harry?’

‘I considered options where two people might survive, rather than three. Or one. By sharing suits.’

The tension between us rose immediately.

Harry said, ‘Of course those spiders also left you Bill’s suit. The trouble is the power store is built into the fabric of each suit. To benefit you’d have to swap suits. I can’t think of any way you could do that without the shelter of the gondola; you’d freeze to death in a second.’

‘So it’s not an option,’ Poole said.

Miriam looked at us both steadily. ‘It never was.’

I wasn’t sure if I was relieved or not, for I had been determined, in those few moments when it seemed a possibility, that the last survivor in the last suit would be myself.

‘So,’ Poole said to Harry, ‘what else?’

‘You need the gondola’s GUTengine to recharge your suits,’ Harry said. ‘There’s just no alternative.’

I pointed at the toiling spiders on the cryovolcano. ‘Those beasts have already thrown it into that caldera.’

‘Then you’ll have to go after it,’ Harry said, and, comfortably tucked up in the Crab , he grinned at me. ‘Won’t you?’

‘How?’ I was genuinely bewildered. ‘Are we going to build a submarine?’

‘You won’t need one,’ Harry said. ‘You have your suits. Just jump in . . .’

‘Are you insane? You want us to jump into the caldera of a volcano, after a bunch of metal-chewing monster spiders?’

But Miriam and Poole, as was their way, had pounced on the new idea. Miriam said, ‘Jovik, you keep forgetting you’re not on Earth. That “volcano” is just spewing water, lava that’s colder than your own bloodstream.’ She glanced at Harry. ‘The water’s very ammonia-rich, however. I take it our suits can stand it?’

‘They’re designed for contact with the mantle material,’ Harry said. ‘We always knew that was likely. The pressure shouldn’t be a problem either.’

Poole said, ‘As for the spiders, they will surely leave us alone if we keep away from them. We know that. We might even use them in the descent. Follow the spiders, find the engine. Right?’

Harry said, ‘And there’s science to be done.’ He displayed data in gleaming Virtual displays – cold summaries only metres away from Bill Dzik’s corpse. Harry said that his preliminary analysis of our results showed that the primary source of the atmosphere’s crucial methane was not in the surface features, but a venting from the cryovolcanoes. ‘And therefore the ultimate source is somewhere in the ammonia sea,’ Harry said. ‘Biological, geological, whatever – it’s down there.’

‘OK,’ Poole said. ‘So we’re not going to complete the picture unless we go take a look.’

‘You won’t be out of touch. I’ll be able to track you, and talk to you all the way in. Our comms link have a neutrino-transmission basis; a few kilometres of ice or water isn’t going to make any difference to that.’

A few kilometres ? I didn’t like the sound of that.

‘So that’s that,’ Miriam said. ‘We have a plan.’

‘We have a shared delusion,’ I said.

They ignored me. Poole said, ‘I suggest we take an hour out. We can afford that. We should try to rest; we’ve been through a lot. And we need to sort through these supplies, figure out what we can use.’

‘Yeah,’ said Miriam. ‘For instance, how about nets of ice as ballast?’

So he and Miriam got down to work, sorting through the junk discarded by the spiders, knotting together cables to make nets. They were never happier than when busy on some task together.

And there was Bill Dzik, lying on his back, stark naked, frozen eyes staring into the murky sky. I think it tells you a lot about Michael Poole and even Miriam that they were so focused on their latest goal that they had no time to consider the remains of this man with whom they had worked, apparently, for decades. Well, I had despised the man, and he had despised me, but something in me cringed at the thought of leaving him like that.

I looked around for something I could use as a shovel. I found a strut and a ceramic panel from some internal partition in the gondola, and used cable to join them together. Then I dug into the soil of Titan. The blade went in easily; the icy sand grains didn’t cling together. As a native of Earth’s higher gravity I was over-powered for Titan, and lifted great shovelfuls easily. But a half-metre or so down I found the sand was tighter packed and harder to penetrate, no doubt some artefact of Titan’s complicated geology. I couldn’t dig a grave deep enough for a man the size of Bill Dzik. So I contented myself with laying him in my shallow ditch, and building a mound over him. Before I covered his face I tried to close his eyes, but of course the lids were frozen in place.