Godlike Machines Read online

  He, the identity copy, died to save my life. I salute him.

  IV

  Wormhole

  Released from my cell of suspended animation, embittered, angry, I chose to be alone. I walked to the very rim of the lifedome, where the transparent carapace met the solid floor. Looking down I could see the flaring of superheated, ionised steam pouring from the GUTdrive nozzles. The engine, as you would expect, was one of Poole’s own designs. “GUT” stands for “Grand Unified Theory,” the system which describes the fundamental forces of nature as aspects of a single super-force. This is creation physics. Thus men like Michael Poole use the energies which once drove the expansion of the universe itself for the triviality of pushing forward their steam rockets.

  Soon the Hermit Crab drove us into the mouth of the wormhole that led to the Saturn system. We flew lifedome first at the wormhole Interface, so it was as if the electric-blue tetrahedral frame came down on us from the zenith. It was quite beautiful, a sculpture of light. Those electric blue struts were beams of exotic matter, a manifestation of a kind of antigravity field that kept this throat in space and time from collapsing. Every so often you would see the glimmer of a triangular face, a sheen of golden light filtering through from Saturn’s dim halls.

  The frame bore down, widening in my view, and fell around us, obscuring the view of Earth and Earthport. Now I was looking up into a kind of tunnel, picked out by the flaring of sheets of light. This was a flaw in spacetime itself; the flashing I saw was the resolution of that tremendous strain into exotic particles and radiations. The ship thrust deeper into the wormhole. Fragments of blue-white light swam from a vanishing point directly above my head and swarmed down the spacetime walls. There was a genuine sensation of speed, of limitless, uncontrollable velocity. The ship shuddered and banged, the lifedome creaked like a tin shack, and I thought I could hear that elderly GUTdrive screaming with the strain. I gripped a rail and tried not to cower.

  The passage was at least mercifully short. Amid a shower of exotic particles we ascended out of another electric-blue Interface—and I found myself back in the Saturn system, for the first time in years.

  I could see immediately that we were close to the orbit of Titan about its primary, for the planet itself, suspended in the scuffed sky of the lifedome, was about the size I remembered it: a flattened globe a good bit larger than the Moon seen from Earth. Other moons hung around their primary points of light. The sun was off to the right, with its close cluster of inner planets, so Saturn was half-full. Saturn’s only attractive feature, the rings, were invisible, for Titan’s orbit is in the same equatorial plane as the ring system and the rings are edge-on. But the shadow of the rings cast by the sun lay across the planet’s face, sharp and unexpected.

  There was nothing romantic in the view, nothing beautiful about it, not to me. The light was flat and pale. Saturn is about ten times as far from the sun as Earth is, and the sun is reduced to an eerie pinpoint, its radiance only a hundredth that at Earth. Saturn is misty and murky, an autumnal place. And you never forgot that you were so far from home that a human hand, held out at arm’s length towards the sun, could have covered all of the orbit of Earth.

  The Crab swung about and Titan itself was revealed, a globe choked by murky brown cloud from pole to pole, even more dismal and uninviting than its primary. Evidently Michael Poole had placed his wormhole interface close to the moon in anticipation that Titan would someday serve his purposes.

  Titan was looming larger, swelling visibly. Our destination was obvious.

  Harry Poole took charge. He had us put on heavy, thick-layered exosuits of a kind I’d never seen before. We sat on our couches like fat pupae; my suit was so thick my legs wouldn’t bend properly.

  “Here’s the deal,” Harry said, evidently for my benefit. “The Crab came out of the wormhole barreling straight for Titan. That way we hope to get you down there before any of the automated surveillance systems up here can spot us, or anyhow do anything about it. In a while the Crab will brake into orbit around Titan. But before then you four in the gondola will be thrown straight into an entry.” He snapped his fingers, and a hatch opened up in the floor beneath us to reveal the interior of another craft, mated to the base of the lifedome. It was like a cave, brightly lit and with its walls crusted with data displays.

  I said, “Thrown straight in, Harry? And what about you?”

  He smiled with that young-old face. “I will be waiting for you in orbit. Somebody has to stay behind to bail you out, in case.”

  “This gondola looks small for the four of us.”

  Harry said, “Well, weight has been a consideration. You’ll mass no more than a tonne, all up.” He handed me a data slate. “Now this is where you come in, Jovik. I want you to send a covering message to the control base on Enceladus.”

  I stared at the slate. “Saying what, exactly?”

  Harry said, “The entry profile is designed to mimic an unmanned mission. For instance you’re going in hard—high deceleration. I want you to make yourselves look that way in the telemetry—like just another unmanned probe, going in for a bit of science, or a curacy inspection, or whatever it is you bureaucrat types do. Attach the appropriate permissions. I’m quite sure you’re capable of that.”

  I was sure of it too. I opened the slate with a wave of my hand, quickly mocked up a suitable profile, let Harry’s systems check I hadn’t smuggled in any cries for help, and squirted it over to Enceladus. Then I handed the slate back. “There. Done. You’re masked from the curacy. I’ve done what you want.” I waved at the looming face of Titan. “So you can spare me from that, can’t you?”

  “We discussed that,” said Michael Poole, with just a hint of regret in his voice. “We decided to take you along as a fallback, Jovik, in case of a challenge. Having you aboard will make the mission look more plausible; you can give us a bit more cover.”

  I snorted. “They’ll see through that.”

  Miriam shrugged. “It’s worth it if it buys us a bit more time.”

  Bill Dzik stared at me, hard. “Just don’t get any ideas, desk jockey. I’ll have my eye on you all the way down and all the way back.”

  “And listen,” Harry said, leaning forward. “If this works out, Jovik, you’ll be rewarded. We’ll see to that. We’ll be able to afford it, after all.” He grinned that youthful grin. “And just think. You will be one of the first humans to walk on Titan. So you see, you’ve every incentive to cooperate, haven’t you?” He checked a clock on his data slate. “We’re close to the release checkpoint. Down you go, team.”

  They all sneered at that word, and at the cheerful tone of the man who was staying behind. But we filed dutifully enough through the hatch and down into that cave of instrumentation, Miriam first, then me, with Bill Dzik at my back. Michael Poole was last in; I saw him embrace his father, stiffly, evidently not a gesture they were used to. In the gondola, our four couches sat in a row, so close that my knees touched Miriam’s and Dzik’s when we were all crammed in there in our suits. The hull was all around us, close enough for me to have reached out and touched it in every direction, a close-fitting shell. Poole pulled the hatch closed, and I heard a hum and whir as the independent systems of this gondola came on line. There was a rattle of latches, and then a kind of sideways shove that made my stomach churn. We were already cut loose of the Crab, and were falling free, and rotating.

  Poole touched a panel above his head, and the hull turned transparent. It was as if we four in our couches were suspended in space, surrounded by glowing instrument panels, and blocky masses that must be the GUT engine, life support, supplies. Above me the Crab slid across the face of Saturn, GUTdrive flaring, and below me the orange face of Titan loomed large.

  I whimpered. I have never pretended to be brave.

  Miriam Berg handed me a transparent bubble-helmet. “Lethe, put this on before you puke.”

  I pulled the helmet over my head; it snuggled into the suit neck and made its own lock.
/>   Bill Dzik was evidently enjoying my discomfort. “You feel safer in the suit, right? Well, the entry is the most dangerous time. But you’d better hope we get through the atmosphere’s outer layers before the hull breaches, Emry. These outfits aren’t designed to work as pressure suits.”

  “Then what?”

  “Heat control,” Michael Poole said, a bit more sympathetic. “Titan’s air pressure is fifty percent higher than Earth’s, at the surface. But that cold thick air just sucks away your heat. Listen up, Emry. The gondola’s small, but it has a pretty robust power supply—a GUT engine, in fact. You’re going to need that power to keep warm. Away from the gondola your suit will protect you, there are power cells built into the fabric. But you won’t last more than a few hours away from the gondola. Got that?”

  I was hardly reassured. “What about the entry itself? Your father said we’ll follow an unmanned profile. That sounds a bit vigorous.”

  Bill Dzik barked a laugh.

  “We should be fine,” Poole said. “We don’t have full inertial control, we don’t have the power, but in the couches we’ll be shielded from the worst of the deceleration. Just sit tight.”

  And then Poole fell silent as he and the others began to work through pre-entry system checks. Harry murmured in my ear, telling me that fresh identity backups had just been taken of each of us and stored in the gondola’s systems. I was not reassured. I lay helpless, trussed up and strapped in, as we plummeted into the center of the sunlit face of Titan.

  V

  Titan

  Fifteen minutes after cutting loose of the Crab, the gondola encountered the first wisps of Titan’s upper atmosphere, thin and cold, faintly blue all around us. Still a thousand kilometers above the ground I could feel the first faltering in the gondola’s headlong speed. Titan’s air is massive and deep, and I was falling backside first straight into it.

  The first three minutes of the entry were the worst. We plunged into the air with an interplanetary velocity, but our speed was reduced violently. Three hundred kilometers above the surface, the deceleration peaked at sixteen gravities. Cushioned by Poole’s inertial field I felt no more than the faintest shaking, but the gondola creaked and banged, every joint and structure stressed to its limits. Meanwhile a shock wave preceded us, a cap of gas that glowed brilliantly: Titan air battered to a plasma by the dissipating kinetic energy of the gondola.

  This fiery entry phase was mercifully brief. But still we fell helplessly. After three minutes we were within 150 kilometers of the surface, and immersed in a thickening orange haze, the organic-chemistry products of the destruction of Titan’s methane by sunlight. Poole tapped a panel. A mortar banged above us, hauling out a pilot parachute a couple of meters across. This stabilized us in the thickening air, our backs to the moon, our faces to the sky. Then a main parachute unfolded sluggishly, spreading reassuringly above me.

  For fifteen minutes we drifted, sinking slowly into a deep ocean of cold, sluggish air. Poole and his colleagues worked at their slates, gathering data from sensors that measured the physical and chemical properties of the atmosphere. I lay silent, curious but frightened for my life.

  As we fell deeper into the hydrocarbon smog the temperature fell steadily. Greenhouse effects from methane products keep Titan’s stratosphere warmer than it should be. Sixty kilometers above the surface we fell through a layer of hydrocarbon cloud into clearer air beneath, and then, at 40 kilometers, through a thin layer of methane clouds. The temperature was close to its minimum here, at only 70 degrees or so above absolute zero. Soon it would rise again, for hydrogen liberated from more methane reactions contribute to another greenhouse effect that warms up the troposphere. The mysterious methane that shouldn’t have been there warms Titan’s air all the way to the ground.

  Fifteen minutes after its unpackaging the main parachute was cut away, and a smaller stabilizer canopy opened. Much smaller. We began to fall faster, into the deep ocean of air. “Lethe,” I said. “We’re still 40 kilometers high!”

  Bill Dzik laughed at me. “Don’t you know anything about the world you’re supposed to be guarding, curator? The air’s thick here, and the gravity’s low, only a seventh of Earth normal. Under that big parachute we’d be hanging in the air all day . . .”

  The gondola lurched sideways, shoved by the winds. At least it shut Dzik up. But the winds eased as we fell further, until the air was as still and turgid as deep water. We were immersed now in orange petrochemical haze. But the sun was plainly visible as a brilliant point source of light, surrounded by a yellow-brown halo. The crew gathered data on the spectra of the solar halo, seeking information on aerosols, solid or liquid particles suspended in the air.

  Gradually, beneath our backs, Titan’s surface became visible. I twisted to see. Cumulus clouds of ethane vapor lay draped over continents of water ice. Of the ground itself I saw a mottling of dark and white patches, areas huge in extent, pocked by what looked like impact craters, and incised by threading valleys cut by flowing liquid, ethane or methane. The crew continued to collect their science data. An acoustic sounder sent out complex pulses of sound. Miriam Berg showed me how some echoes came back double, with reflections from the surfaces and bottoms of crater lakes, like the one my sampling probe had entered.

  The gondola rocked beneath its parachute. Poole had suspended his inertial shielding, and under not much less than Titan’s one-seventh gravity I was comfortable in my thick, softly layered exosuit. The crew’s murmuring as they worked was professional and quiet. I think I actually slept, briefly.

  Then there was a jolt. I woke with a snap. The parachute had been cut loose, and was drifting away with its strings dangling like some jellyfish. Our fall was slow in that thick air and gentle gravity, but fall we did!

  And then, as Bill Dzik laughed at me, a new canopy unfurled into the form of a globe, spreading out above us. It was a balloon, perhaps 40, 50 meters across; we were suspended from it by a series of fine ropes. As I watched a kind of hose snaked up from beneath the gondola’s hull, and pushed up into the mouth of the balloon, and it began to inflate.

  “So that’s the plan,” I said. “To float around Titan in a balloon! Not very energetic for a man who builds interplanetary wormholes, Poole.”

  “But that’s the point,” Poole said testily, as if I had challenged his manhood. “We’re here under the noses of your curators’ sensors, Emry. The less of a splash we make the better.”

  Miriam Berg said, “I designed this part of the mission profile. We’re going to float around at this altitude, about eight kilometers up-well above any problems with the topography but under most of the cloud decks. We ought to be able to gather the science data we need from here. A couple of weeks should be sufficient.”

  “A couple of weeks in this suit!”

  Poole thumped the walls of the gondola. “This thing expands. You’ll be able to get out of your suit. It’s not going to be luxury, Emry, but you’ll be comfortable enough.”

  Miriam said, “When the time comes we’ll depart from this altitude. The Crab doesn’t carry an orbit-to-surface flitter, but Harry will send down a booster unit to rendezvous with us and lift the gondola to orbit.”

  I stared at her. “We don’t carry the means of getting off this moon?”

  “Not on board, no,” Miriam said evenly. “Mass issues. The need to stay under the curacy sensors’ awareness threshold. We’re supposed to look like an unmanned probe, remember. Look, it’s not a problem.”

  “Umm.” Call me a coward, many have. But I didn’t like the idea that my only way off this wretched moon was thousands of kilometers away, and depended on a complicated series of rendezvous and coupling manoeuvres. “So what’s keeping us aloft? Hydrogen, helium?”

  Poole pointed at that inlet pipe. “Neither. This is a hot air balloon, Emry, a Montgolfier.” And he gave me a lecture on how hot-air technology is optimal if you must go ballooning on Titan. The thick air and low gravity make the moon hospitable for balloons, and at s
uch low temperatures you get a large expansion in response to a comparatively small amount of heat energy. Add all these factors into the kind of tradeoff equation men like Poole enjoy so much, and out pops hot-air ballooning as the low-energy transport of choice on Titan.

  Miriam said, “We’re a balloon, not a dirigible; we can’t steer. But for a mission like this we can pretty much go where the wind takes us; all we’re doing is sampling a global ecosphere. And we can choose our course to some extent. The prevailing winds on Titan are easterly, but below about two kilometers there’s a strong westerly component. That’s a tide, raised by Saturn in the thick air down there. So we can select which way we get blown, just by ascending and descending.”

  “More stealth, I suppose. No need for engines.”

  “That’s the idea. We’ve arrived in the local morning. Titan’s day is 15 Earth days long, and we can achieve a lot before nightfall—in fact I’m intending that we should chase the daylight. Right now we’re heading for the south pole, where it’s summer.” And there, as even I knew, methane and ethane pooled in open lakes—the only stable such liquid bodies in the System, save only for those on Earth and Triton.

  “Summer on Titan,” Poole said, and he grinned. “And we’re riding the oldest flying machine of all over a moon of Saturn!” Evidently he was starting to enjoy himself.

  Miriam smiled back, and their gloved hands locked together.

  The envelope snapped and billowed above us as the warm air filled it up.

  VI

  Landfall

  So we drifted over Titan’s frozen landscape, heading for the south pole. For now Michael Poole kept us stuck in that unexpanded hull, and indeed inside our suits, though we removed our helmets, while the crew put the gondola through a fresh series of post-entry checks. I had nothing to do but stare out of the transparent hull, at the very Earthlike clouds that littered the murky sky, or over my shoulder at the landscape that unfolded beneath me.