The Mammoth Book of Best New SF 24
Page 63
There was nothing to be done but to endure the ride. It would take perhaps a further day. So Poole and Miriam allowed the spider to drag us down. More tube-fish, of an exotic high-pressure variety, grazed endlessly at the icy walls. Miriam popped me another vial to keep me asleep, and fed me intravenous fluids. Harry fretted about the exhaustion of our power, and the gradual increase of pressure; beneath a column of water and ice hundreds of kilometres deep, we were approaching our suits’ manufactured tolerance. But they had no choice to continue, and I, unconscious, had no say in the matter.
When the ride was over, when the spider had at last come to rest, Miriam woke me up.
I was lying on my back on a lumpy floor. The gravity felt even weaker than on the surface. Miriam’s face hovered over me, illuminated by suit lamps. She said, “Look what we found.”
I sat up. I felt weak, dizzy – hungry. Beside me, in their suits, Miriam and Poole sat watching my reaction. Then I remembered where I was and the fear cut in.
I looked around quickly. Even by the glow of the suit lamps I could not see far. The murkiness and floating particles told me I must be still immersed in the water of Titan’s deep ocean. I saw a roof of ice above me – not far, a hundred metres or so. Below me was a surface of what looked like rock, dark and purple-streaked. I was in a sort of ice cavern, then, whose walls were off in the dark beyond our bubble of light. I learned later that I was in a cavern dug out beneath the lower icy mantle of Titan, between it and the rocky core, eight hundred kilometres below the icy plains where I had crash-landed days before. Around us I saw ice spiders, toiling away at their own enigmatic tasks, and bits of equipment from the gondola, chopped up, carried here and deposited. There was the GUT engine! My heart leapt; perhaps I would yet live through this.
But even the engine wasn’t what Miriam had meant. She repeated, “Look what we found.”
I looked. Set in the floor, in the rocky core of the world, was a hatch.
XIII
Hatch
They allowed me to eat and drink, and void my bladder. Moving around was difficult, the cold water dense and syrupy; every movement I made was accompanied by the whir of servomotors, as the suit laboured to assist me.
I was reassured to know that the GUT engine was still functioning, and that my suit cells had been recharged. In principle I could stay alive long enough to get back to the Hermit Crab. All I had to do was find my way out of the core of this world, up through eight hundred kilometres of ice and ocean . . . I clung to the relief of the moment, and put off my fears over what was to come next.
Now that I was awake, Michael Poole, Miriam Berg, and Virtual Harry rehearsed what they had figured out about methane processing on Titan. Under that roof of ice, immersed in that chill high-pressure ocean, they talked about comets and chemistry, while all the while the huge mystery of the hatch in the ground lay between us, unaddressed.
Harry said, “On Earth ninety-five per cent of the methane in the air is of biological origin. The farts of animals, decaying vegetation. So could the source be biological here? You guys have surveyed enough of the environment to rule that out. There could in principle be methanogen bugs living in those ethane lakes, for instance, feeding off reactions between acetylene and hydrogen, but you found nothing significant. What about a delivery of the methane by infalling comets? It’s possible, but then you’d have detected other trace cometary gases, which are absent from the air. One plausible possibility remained . . .”
When Titan was young its ammonia-water ocean extended all the way to the rocky core. There, chemical processes could have produced plentiful methane: the alkaline water reacting with the rock would liberate hydrogen, which in turn would react with sources of carbon, monoxide or dioxide or carbon grains, to manufacture methane. But that process would have been stopped as soon as the ice layers plated over the rock core, insulating it from liquid water. What was needed, then, was some way for chambers to be kept open at the base of the ice, where liquid water and rock could still react at their interface. And a way for the methane produced to reach the ocean, and then the surface.
“The methane could be stored in clathrates, ice layers,” Harry said. “That would work its way to the surface eventually. Simpler to build vents up through the ice, and encourage a chemoautotrophic ecosystem to feed off the methane, and deliver it to higher levels.”
“The tube-fish,” I said.
“And their relatives, yes.”
Looking up at the ice ceiling above me, I saw how it had been shaped and scraped, as if by lobster claws. “So the spiders keep these chambers open, to allow the methane-creating reactions to continue.”
“That’s it,” Michael Poole said, wonder in his voice. “They do it to keep a supply of methane pumping up into the atmosphere. And they’ve been doing it for billions of years. Have to have been, for the ecologies up there to have evolved as they have – the tube-fish, the CHON sponges, the silanes. This whole world is an engine, a very old engine. It’s an engine for creating methane, for turning what would otherwise be just another nondescript ice moon into a haven, whose purpose is to foster the life forms that inhabit it.”
“Why would they do that?”
None of them could answer that.
“Ha!” I barked laughter. “Well, the why of it is irrelevant. The spiders are clearly sentient – or their makers are. You have found precisely what you were afraid of, haven’t you, Michael Poole? Sentience at the heart of Titan. You will never be allowed to open it up for exploitation now. So much for your commercial ambitions!”
“Which you were going to share in,” Harry reminded me, scowling.
I sneered. “Oh, I’d only have wasted the money on drugs and sex. To see you world-builders crestfallen is worth that loss. So what’s under the hatch?”
They glanced at each other. “The final answers, we hope,” Michael Poole said.
Miriam said, “We’ve put off looking under there until we brought you round, Jovik.”
Poole said, “We’ve no idea what’s under there. We need everybody awake, ready to react. We might even need your help, Emry.” He looked at me with faint disgust. “And,” he said more practically, “it’s probably going to take three of us to open it. Come see.”
We all floated through the gloopy murk.
The hatch was a disc of some silvery metal, perhaps three metres across, set flush into the roughly flat rocky ground. Spaced around its circumference were three identical grooves, each maybe ten centimetres deep. In the middle of each groove was a mechanism like a pair of levers, hinged at the top.
Michael said, “We think you operate it like this.” He knelt and put his gloved hands to either side of the levers, and mimed pressing them together. “We don’t know how heavy the mechanism will be. Hopefully each of us can handle one set of levers, with the help of our suits.”
“Three mechanisms,” I said. “This is a door meant to be operated by a spider, isn’t it? One handle for each of those three big claws.”
“We think so,” Miriam said. “The handles look about the right size. We think the handles must have to be worked simultaneously – one spider, or three humans.”
“I can’t believe that after a billion years all they have is a clunky mechanical door.”
Poole said, “It’s hard to imagine a technology however advanced that won’t have manual backups. We’ve seen that the spiders themselves aren’t perfect; they’re not immune to breakdown and damage.”
“As inflicted by us.” I gazed reluctantly at the hatch. “Must we do this? You’ve found what you wanted – or didn’t want. Why expose us to more risk? Can’t we just go home?”
Miriam and Michael just stared at me, bewildered. Miriam said, “You could walk away, without knowing?”
Poole said, “Well, we’re not leaving here until we’ve done this, Emry, so you may as well get it over.” He crouched down by his handle, and Miriam did the same.
I had no choice but to join them.
P
oole counted us down: “Three, two, one.”
I closed my gloved hands over the levers and pushed them together. It was awkward to reach down, and the mechanism felt heavy; my muscles worked, and I felt the reaction push me up from the floor. But the levers closed together.
The whole hatch began to vibrate.
I let go and moved back quickly. The others did the same. We stood in a circle, wafted by the currents of the ammonia sea, and watched that hatch slide up out of the ground.
It was like a piston, rising up one metre, two. Its sides were perfectly smooth, perfectly reflective, without a scuff or scratch. I wondered at how old it must be. Michael Poole, fool that he was, reached up a gloved monkey-curious hand to touch it, but Miriam restrained him. “I’d like to measure the tolerances on that thing,” he murmured.
Then the great slab, around three metres wide and two tall, slid sideways. Poole had to step out of the way. The scrape across the rough rock ground was audible, dimly. The shift revealed a hole in the ground, a circle – and at first I thought it was perfectly black. But then I saw elusive golden glimmers, sheets of light like soap bubbles; if I turned my head a little I lost it again.
“Woah,” Harry Poole said. “There’s some exotic radiation coming out of that hole. You should all back off. The suits have heavy shielding, but a few metres of water won’t hurt.”
I didn’t need telling twice. We moved away towards the GUT engine, taking the light with us. The hole in the ground, still just visible in the glow of our suit lamps, looked a little like one of the ethane lakes on the surface, with that metallic monolith beside it. But every so often I could make out that elusive golden-brown glimmer. I said, “It looks like a facet of one of your wormhole Interfaces, Poole.”
“Not a bad observation,” Poole said. “And I have a feeling that’s exactly what we’re looking at. Harry?”
“Yeah.” Harry was hesitating. “I wish you had a better sensor suite down there. I’m relying on instruments woven into your suits, internal diagnostic tools in the GUT engine, some stray neutrino leakage up here . . . Yes, I think we’re seeing products of stressed spacetime. There are some interesting optical effects too – light lensed by a distorted gravity field.”
“So it’s a wormhole Interface?” Miriam asked.
“If it is,” Poole said, “it’s far beyond the clumsy monstrosities we construct in Jovian orbit. And whatever is on the other side of that barrier, my guess is it’s not on Titan . . .”
“Watch out,” Miriam said.
A spider came scuttling past us towards the hole. It paused at the lip, as if puzzled that the hole was open. Then it tipped forward, just as the spider we rode into the volcano had dipped into the caldera, and slid head first through that sheet of darkness. It was as if it had fallen into a pool of oil that closed over the spider without a ripple.
“I wouldn’t recommend following,” Harry said. “The radiations in there are deadly, suit or no suit; you couldn’t survive the passage.”
“Lethe,” Michael Poole said. He was disappointed!
“So are we done here?” I asked.
Poole snapped, “I’ll tell you something, Emry, I’m glad you’re here. Every time we come to an obstacle and you just want to give up, it just goads me into trying to find a way forward.”
“There is no way forward,” I said. “It’s lethal. Harry said so.”
“We can’t go on,” Miriam agreed. “But how about a probe? Something radiation-hardened, a controlling AI – with luck we could just drop it in there and let it report back.”
“That would work,” Poole said. Without hesitation the two of them walked over to the GUT engine, and began prying at it.
For redundancy the engine had two control units. Miriam and Poole detached one of these. Containing a sensor suite, processing capabilities, a memory store, it was a white-walled box the size of a suitcase. Within this unit and its twin sibling were stored the identity backups that had been taken of us before our ride into Titan’s atmosphere. The little box was even capable of projecting Virtuals; Harry’s sharp image was being projected right now by the GUT engine hardware, rather than through a pooling of our suits’ systems as before.
The box was small enough just to be dropped through the Interface, and hardened against radiation. It would survive a passage through the wormhole – though none of us could say if it would survive what lay on the other side. And it had transmitting and receiving capabilities. Harry believed its signals would make it back through the interface, though probably scrambled by gravitational distortion and other effects, but he was confident he could construct decoding algorithms from a few test signals. The unit was perfectly equipped to serve as a probe through the hatch, save for one thing. What the control box didn’t have was intelligence.
Michael Poole stroked its surface with a gloved hand. “We’re sending it into an entirely unknown situation. It’s going to have to work autonomously, to figure out its environment, work out some kind of sensor sweep, before it can even figure out how to talk to us and ask us for direction. Running a GUT engine is a pretty simple and predictable job; the AI in there isn’t capable of handling an exploration like these.”
“But,” I said, “it carries in its store backups of four human intellects – mine, dead Bill, and you two geniuses. What a shame we can’t all ride along with it!”
My sarcasm failed to evoke the expected reaction. Poole and Miriam looked at each other, electrified. Miriam shook her head. “Jovik, you’re like some idiot savant. You keep on coming up with such ideas. I think you’re actually far smarter than you allow yourself to be.”
I said honestly, “I have no idea what you’re talking about.”
“The idea you’ve suggested to them,” Harry said gently, “is to revive one of the dormant identity-backup copies in the unit’s store, and use that as the controlling intelligence.”
As always when they hit on some new idea Poole and Miriam were like two eager kids. Poole said, “It’s going to be a shock to wake up, to move straight from Titan entry to this point. It would be least disconcerting if we projected a full human animus.”
“You’re telling me,” said the head of Harry Poole.
“And some enclosing environment,” Miriam said. “Just a suit? No, to be adrift in space brings in problems with vertigo. I’d have trouble with that.”
“The lifedome of the Crab,” Poole said. “That would be straightforward enough to simulate to an adequate degree. And a good platform for observation. The power would be sufficient to sustain that for a few hours at least . . .”
“Yes.” Miriam grinned. “Our observer will feel safe. I’ll get to work on it . . .”
I asked, “So you’re planning to project a Virtual copy of one of us through the wormhole. And how will you get him or her back?”
They looked at me. “That won’t be possible,” Poole said. “The unit will be lost. It’s possible we could transmit back a copy of the memories the Virtual accrues on the other side – integrate them somehow with the backup in the GUT engine’s other store — ”
“No,” Harry said regretfully. “The data rate through that Interface would never allow even that. For the copy in there it’s a one way trip.”
“Well, that’s entirely against the sentience laws,” I put in. They ignored me.
Poole said, “That’s settled, then. The question is, who? Which of the four of us are you going to wake up from cyber-sleep and send into the unknown?”
I noticed that Harry’s disembodied floating head looked away, as if he were avoiding the question.
Poole and Miriam looked at each other. Miriam said, “Either of us would go. Right?”
“Of course.”
“But we should give it to Bill,” Miriam said firmly.
“Yeah. There’s no other choice. Bill’s gone, and we can’t bring his stored backup home with us . . . We should let his backup have the privilege of doing this. It will make the sacrifice worthwhile.”
Poole glared at me. “Bill won’t see it that way, believe me. You and a man like Bill Dzik have nothing in common, Emry. Don’t judge him by your standards.”
“Fine. Just don’t send me.”
“Oh, I won’t. You don’t deserve it.”
It took them only a few more minutes to prepare for the experiment. The control pack didn’t need any physical modifications, and it didn’t take Miriam long to programme instructions into its limited onboard intelligence. She provided it with a short orientation message, in the hope that Virtual Bill wouldn’t be left entirely bewildered at the sudden transition he would experience.
Poole picked up the pack with his gloved hands, and walked towards the Interface, or as close as Harry advised him get. Then Poole hefted the pack over his head. “Good luck, Bill.” He threw the pack towards the Interface, or rather pushed it; its weight was low but its inertia was just as it would have been on Earth, and besides Poole had to fight against the resistance of the syrupy sea. For a while it looked as if the pack might fall short. “I should have practiced a couple of times,” Poole said ruefully. “Never was any use at physical sports.”
But he got it about right. The pack clipped the rim of the hole, then tumbled forward and fell slowly, dreamlike, through that black surface. As it disappeared autumn gold glimmered around it.
Then we had to wait, the three of us plus Harry. I began to wish that we had agreed some time limit; obsessives like Poole and Miriam were capable of standing there for hours before admitting failure.
In the event it was only minutes before a scratchy voice sounded in our suit helmets. “Harry? Can you hear me?”
“Yes!” Harry called, grinning. “Yes, I hear you. The reception ought to get better, the clean-up algorithms are still working. Are you all right?”
“Well, I’m sitting in the Crab lifedome. It’s kind of a shock to find myself here, after bracing my butt to enter Titan. Your little orientation show helped, Miriam.”