Titan

by Stephen Baxter

  “I still don’t get it. Even if I find the ponds, even if I seed them, they’re just going to freeze over, in a few hundred or a thousand years.”

  “Sure.”

  “So what’s the point?”

  He shuddered. “Things will change. In time—billions of years, Paula—the sun will reach the end of its life. It will become a red giant… And then, for a time, Titan will be as warm as the Earth. Titan summer. Maybe our bacterial spores will give rise to a new evolutionary sequence. You see?”

  She pulled back from him. Suddenly she felt chilled. “You think big, Rosenberg.”

  “Little packets of bacteria… Seed the planets, the comets. If you’re serious about spreading life to other worlds, that’s how you’d do it. Cheap, too. It’s absurd to carry humans around … all that plumbing…” His eyes closed, the big broken lids sweeping down like curtains.

  She picked him up, and carried him to the hygiene station.

  Sitting on the floor of the hab module, a Beta-cloth blanket thrown over them both, she cradled him. His head felt huge in her lap, the massive skull with its paper-thin covering of flesh and skin, but his body was feather-light.

  He whispered: “How can I die? How can the world keep turning without me? I’m unique, Paula. The center of the universe. The one true sentient individual in an ocean of shapes and noises and faces. How can I die? It’s a cruel joke.”

  Dear Rosenberg. Analytical to the end.

  “They’ll remember you for coming to Titan. A member of the first expedition. That’s one hell of a memorial.”

  “If there is anyone left to remember. Anyhow, even so, I’ll just be a freak in a circus show.”

  She said gently, “No god waiting for you, Rosenberg?”

  He tried to laugh. He whispered, “What do you think? God died in 1609, when Galileo raised his telescope to the Moon, and saw seas and mountains. We flew to Titan. But with that one act Galileo discovered the Universe. God can’t share the same cosmos as a Moon like that.”

  “No,” Benacerraf said sadly. “No, I don’t suppose He can. But where does that leave us, Rosenberg?”

  “Fucked,” he said brutally “Science is a system of knowledge, Paula. Not a comfort.”

  “I know,” she said. She stroked his forehead, and crooned her words, as if to a sick child. “I know.”

  He gripped her arm with a clawlike hand. “Paula. You have to put me through the SCWO.”

  “Sure, Rosenberg.”

  “I mean it. You can’t afford to waste the biomass. But freeze yourself, Paula. Go out on the ice, when… It’s important…”

  He coughed, but even that had lost its vigor. The color seemed to be draining from his face, even from the exposed tissue there, as if his blood was drawing back to the core of his body.

  His head rolled on its spindle of neck across her lap. “You know, I’m not afraid. I thought I would be. I’m not.”

  She squeezed his hand; it felt as if his bones were grinding together. “You don’t need to be afraid, Rosenberg. I’m here.”

  He said, with a spark of sour energy, “It isn’t that. The human stuff, monkeys holding hands against the dark. I never thought that would make any difference. And I was right. But you and I—”

  He coughed, and shuddered; his ruined eyes fluttered closed.

  She leaned over, closer to his bleeding mouth.

  “You and I, with what we’re doing here, are the most important humans who ever lived. We will cast a shadow across five billion years. And that’s a hell of a thing,” he whispered. “A hell of a thing.”

  He relaxed, with a rattling sigh, and lay still, collapsing into her arms with a slow-motion, low-gravity calmness. “You know, I learned a lot,” he whispered. “More than I expected.”

  “You did good, Rosenberg.”

  “But you know, I never figured out why…”

  “What?”

  “Why did it feel like this?”

  She could feel his body settle, the internal organs relaxing and losing their tension; the last gases escaped from his stomach in a long, low fart.

  She got him into the frigid ground only an hour later.

  The grave was just a shallow ditch, scraped out of the gumbo, already infilling. His naked body lay at its base, thin, skeletal, glistening with the frozen water ice of his body.

  Once again she had to find words to say over a corpse.

  She checked her transmission link to Cassini. She wanted this moment to be sent to Earth. Maybe there was somebody there to listen; maybe not. If there was, maybe this would somehow help them.

  “I’m sorry I didn’t have a flag to wrap you in, Rosenberg,” she said. “Anyhow, I know this was what you wanted, in spite of what you said. And if you think I was going to have your sorry ass circulating around my ecosystem, you got another think coming.

  “Casting a shadow across five eons. Maybe you will at that. You did good, Rosenberg.”

  I guess that will do, she thought.

  She threw a handful of Othrys ice crystals into the grave, and began to drag her snowshovel over the gumbo, filling in the shallow pit.

  In the last days she spent a lot of time in the CELSS farm, trying to stabilize it as much as she could. She kept power supplied to the farm, and left it seeded with a new crop, of wheat, barley and lettuce.

  She felt a great responsibility for the drawn, etiolated little plants here. They were, after all, the only living things other than herself on this whole moon, and she felt loyal to them, and regretted she was abandoning them to die.

  But there wasn’t much she could do for them. She figured the CELSS farm might last without human intervention a few weeks, before a pump broke down, or a nutrient pipe clogged, or a short burned out half the lamps, or some runaway feedback biocycle caused the miniature ecology to crash.

  Even if by some miracle that didn’t happen, eventually the power from the Topaz reactors in Discovery’s cargo bay would fail. The lights would dim, and the last, spindly plants would finally die, as Titan’s cold broke in.

  She took spare seeds and wrapped them in airtight bags. She buried them, under a marker, in the gumbo outside Bifrost. That way, perhaps they would survive, deep-frozen, until Discovery’s next visitors came this way, whatever became of her.

  She spent a last night in the hab module. She took a long, hot, luxurious shower, extravagantly spending the reactors’ reserves of energy.

  She tried to read a book on her softscreen, but could barely concentrate. She kept on thinking that this would likely be the last book she ever read. The words seemed just a foolish dancing, against dark emptiness.

  She put the softscreen aside.

  She looked at her images of Jackie and her grandchildren. She stared into the sunny photos, trying to will herself into the pictures with her family.

  She slept well, in her quarters, with the lights off and the door closed, shut in against the shells of emptiness around her: the deserted hab module, the empty moon, the billion miles separating her from Earth.

  When she woke she ate a gigantic breakfast, using up a lot of stores: dried apricots, an irradiated breakfast roll, rehydrated granola with blueberries, ground beef with pickle sauce, noodles and chicken, stewed tomato, pears, almonds, drinks of grapefruit and strawberry.

  She went to the hygiene station and took a long, slow, luxurious dump. She cleaned herself with antiseptic wet-wipes.

  She stripped naked. She folded up her Beta-cloth clothes neatly and put them away in a drawer. She washed one last time, then put plasters and bandages over the places where she knew to expect problems from cold and pressure sores: her toes and ankles and the sides of her feet, her hips, stomach, chest and shoulders. She put cream—all that was left was the hemorrhoid ointment—over her groin, in anticipation of crotch rot.

  She pulled on her suit. She took great care over each layer; she wouldn’t get another chance to fix it, and she would hate to go to her destiny with a fold in her underwear rucked up her ass. />
  Inside the suit layers, duct-taped to the fabric, she stored Rosenberg’s canister of bacteria samples—protected there against the cold—and a little packet of photographs, old-fashioned hard-copy images, of Jackie and the kids.

  She sealed up her helmet, gloves and boots, and ran methodically through the suit checklist fixed in its ring binder to her arm. She went through the list twice. In a way her biggest dread, now she was alone, was that without anyone to check her she would miss out some crucial step, kill herself through carelessness.

  She looked around the hab module one last time before leaving it. It was clean, tidy, everything stowed away, as if ready for reoccupation. She felt obscurely proud; she’d remained civilized to the end.

  Just like Captain Scott.

  She slipped on her Apollo hull-metal snowshoes and stepped out into the gumbo. The tholin slush sucked at her feet with its familiar stickiness, and she felt Titan cold immediately seeping through the layers of her suit.

  She looked over Tartarus Base.

  She could make out the delta shape of the grounded orbiter, with the cone of the Command Module alongside. The cover they had erected over the open cargo bay of the orbiter was still in place, the parachute fabric stiff and streaked with gumbo. In a final extravagant gesture she’d left the flood lights of Discovery’s flight deck burning; the yellow Earth-like light now glared out through tholin-streaked windows, shining over glimmering slush.

  There was little geologic activity here; the ground was stable. Even the tholin deposition rate was slow. It might take a billion years, Benacerraf thought. But at last Titan would claim Tartarus, its patient tholin drizzle ultimately covering over the pyramidal peak of Apollo, Discovery’s big boattail. The spacecraft hulls would ultimately crumple and shatter, until nothing remained of this, the first human outpost on another planet, save a thin, isolated layer of metallic crystals, and a few anomalous deposits of organic residue.

  She looked up, towards the marginally lighter horizon. She cut in her IR visor and made out the spark of light, pixel-blurred, that was the sun. From here, the entire orbit of Earth was a circle the size of a small plate held at arm’s length, with the planet itself—with all its freight of humanity, and hope and love and war and history—a dull-glowing bead on the rim of that circle, impossible to make out. She could hold up her bulky gloved hand and obscure the entirety of the orbit, the whole span of human experience before the Discovery expedition.

  She buckled the Command Module couch harness around her. She dug her snowshoes into the gumbo and shoved. Immediately she felt twinges from the sites of the pressure sores she’d suffered last time, at her hips and chest and shoulders.

  The sled came free of the clinging gumbo with a sucking noise. She staggered forward.

  The sled was heavier, this time, than when she’d set out for her previous extended EVA with Rosenberg. This time, all the essentials—the tent, the recharged skimmer power cells, all her food and water—were stacked high on this one sled.

  On the other hand, her food load was lessened. Just enough for a one way trip.

  Soon, she managed to settle into a steady rhythm, with each step jerking the sled free of the gumbo which clutched at it.

  Every instinct told her that Rosenberg’s billion-year scheme couldn’t work.

  It was, of course, a typically arrogant technocratic fantasy—in a way an extension of the gigantic, ludicrous journey they had undertaken to come here—to suppose that it would be possible, with a handful of micro-organisms thrown into a lake of ejecta melt, to reach out across billions of years and shape the evolution of a world.

  For instance, Rosenberg had made a lot of assumptions about the viability of bacterial spores over such huge deserts of time. And who could really say what the future evolution of the sun would be like? Nobody had actually watched a star follow through its ten-billion-year evolutionary cycle, from birth to death; every theory was inferred from humankind’s mayfly-like snapshot perception of the stars that happened to be scattered through the universe today. Maybe the red giant sun would grow so huge it overwhelmed Titan, boiling away its atmosphere in moments. Or maybe the sun would just go nova, blasting Saturn and its ancient moons to fragments…

  It was, she thought, a pretty dumb plan.

  But, in the end, it gave her a goal.

  Thus her life would end, she thought: struggling to fulfill another project, one more technological dream, because she had nothing better to do.

  After a few paces she looked back. Tartarus Base was already lost in the thickening orange haze, the deepening gloom of Titan twilight.

  After forty-eight hours, the last light had leaked out of the orange haze layers.

  Benacerraf walked through the dark, fighting the resistance of the invisible gumbo as it sucked at her sled and snowshoes. All she could see was the splash of lamp-light on the glistening gumbo hide ahead of her, its diffuse reflection from her own nose and eye ridges, the ancient bone structure of her own human face.

  Titan was a world of enclosure.

  She lost track of time, of the day-night cycle of the distant Earth. She would check her Rolex in the light of her lamp, and find that ten, or twelve, or fourteen hours had worn away, as she had driven on through her tunnel of blindness, dark save for the splash of light from her helmet lamp, silent save for the scratch of her breathing, the whir of fans and pumps in her backpack, the muttering of her own voice.

  … She brooded. What if Rosenberg had been right, in his worst-case projections?

  What if the clouds had rolled over the face of Earth—what if she was, truly, the last spark of awareness in the Solar System?

  There were theories that consciousness was a quantum process. That reality—the Universe itself—was called into existence by conscious minds, as, by observation, they collapsed the infinite possibilities of each quantum wave function into a single, definite event, embedded in history.

  The Universe, it was said, needed consciousess to create itself.

  Then what if she was the last?

  Here she was in this bubble of darkness, the limits of her personal cosmos reaching no more than five or six feet in any direction. Was there anything beyond the intangible walls of the hazy dark? Did she call into existence new stretches of the gumbo as she walked over them?

  If she did not look at the Earth, did Earth any longer exist?

  And when she died, as the last bit of consciousness departed, would the world—Titan and ringed Saturn and the remote sun and Earth and the stars—would all of it fold away and dissolve, with the cold gray light underlying creation breaking through, like a projector’s lamp through a trapped and burning film frame?

  At times she felt more frightened than she’d ever been in her life.

  She welcomed the familiar pain of the harness pressure points and in her feet. The pain gave her something to think about, outside her own sterile thoughts.

  She made camp, proceeding slowly and carefully, double-checking every step before she trusted herself to crack the seal of her suit.

  She cleaned herself out. She felt free to dump her bags of frozen urine and feces rather than haul them with her. She tended clumsily to her various wounds and injuries.

  She developed another big, ugly abscess, this time on her right foot around the ankle, where a flaw in her boot had rubbed and caused her skin to blister. She decided she had to lance it. She took a sterilized scalpel, closed her eyes and stabbed at the abscess, letting the momentum of her bunched fist ram the blade into her flesh. The pain was extraordinary, sharp, and penetrating, much worse than when Rosenberg had operated on the same kind of injury.

  When she looked down, pale, watery pus was leaking from the wound. She squeezed out as much matter as she could, and wiped the incision with a scrap of parachute fabric. Then she dosed it with antiseptic fluid and dressed it.

  She ate from a packet of reheated soup, and drank melted Othrys water. Then she sealed up her suit and lay down against the plastic tent
wall, layers of parachute fabric beneath her.

  She propped her photographs in front of her helmet. She stared into those fragments of bright Seattle daylight, trying to believe she wasn’t alone, as she waited for sleep to claim her.

  She made rapid progress.

  She reached Cronos, and crossed its rim of pressure ridges. She skirted the walls of the crater they’d called El Dorado.

  She walked into Titan’s murky daylight once more.

  Beyond El Dorado, high on the gumbo-stained ice plateau of Cronos, she came to a ridge of broken, jumbled ice, maybe twenty feet tall. She had trouble hauling her sled over this; several times she had to go back and grab the lip of the sled, dragging it bodily up and over.

  When she reached the crest of the ridge, she was facing a plain that looked as if it had been crudely assembled from jammed-together blocks of ice. Pressure ridges criss-crossed it.

  The persistent, bone-deep cold seemed to recede. It was warmer here.

  She descended the ridge, and began to make her way over the plain. The blocks and upthrust ribs in the ice were a foot or more high, and frequently snagged the runners of her sled. The ice creaked and shuddered; evidently great plates of it were sliding over each other in vast tectonic evolutions. She had the sense of riding the scaly hide of some huge, sluggish animal. But that elusive warmth seemed to gather.

  She stopped. With the edge of her ski she scraped away the thin layer of gumbo and loose ice crystals from the surface.

  The ice seemed thin: perhaps a foot thick, or even less. She thought she could see a dark liquid beneath the complex flaws of the ice, and bubbles of some gas trapped there.

  At last she came to a dark break in the ice surface. It was a lead, a stretch of open water, within a crack in the ice maybe six inches deep. The water was dark and scummy, polluted with tholin and hydrocarbons.

  “Hot damn,” she said. “You were right, Rosenberg. I wish you could have gotten to see this.”