The Hard SF Renaissance

by David G. Hartwell

  There wasn’t much to see, the passage was wide, broadened perhaps by eons of flow. Strobes revealed a fob of bubbles around me, otherwise the darkness smothered everything.

  The line drew us up? down? to the inside of the passage, out of the current. I grabbed the line and walked lightly against the tension of the pulling line as if I were rappelling on a low gravity world. The tent with my companions and our pallets were thus spared bumping along the rough surface.

  I asked for the time display, and my helmet told me we’d been under for an hour.

  We rounded a corner and entered a much narrower passage. I became so busy steering us around various projections that I forgot how cold I was. But I noted my skin starting to itch. Then I caught a flash of light ahead. Did I imagine it?

  No. In much less time than I thought, the flash repeated, showing a frothy hole in the liquid above us. Then we were at the boiling surface and Randi was waving at us as she pulled us to shore.

  I flew out of the water with a kick and a flap of my hands and was in her arms. A minute must have passed before I thought to release the rest of the expedition from their tent cum submarine.

  “No solid ground at the end of the main branch. I came up in a boiling sea, full of froth and foam, couldn’t see anything. Not even a roof. Had to come back and take the detour.” She trembled. “I have to get in a tent quick.”

  But with all our decontamination procedures, there was no quick about it, and it was 0300 universal on day ten before we were finally back in our tubular cocoons. By that time, Randi was moaning, shivering and only half conscious. The Exoderm came off as I peeled her tightsuit down and her skin was a bright angry red, except for her fingers and toes, which were an ugly yellow black. I linked up the minidoc and called Cathy, who programmed a general tissue regenerative, a stimulant, and directed that the tent’s insulation factor be turned up.

  By 0500, Randi was sleeping, breathing normally, and some of the redness had faded. Cathy called and offered to watch the minidoc so I could get some sleep.

  The question I fell asleep with was, that with everyone’s lives at stake, could I have pushed myself so far?

  Day ten was a short one. We were all exhausted, we didn’t get started until 1500. Randi looked awful, especially her hands and feet, but pulled on her backup tightsuit without a complaint. My face must have told her what I was thinking because she shot me a defiant look.

  “I’ll do my pitch.”

  But Cathy was waiting for us and took her back into the tent, which repressurized. Nikhil and I shrugged and busied ourselves packing everything else. When the women reappeared, Cathy declared, very firmly, that Randi was to stay prone and inactive.

  Randi disagreed. “I do my pitch … I, I, have to.”

  My turn. “Time to give someone else a chance, Randi. Me for instance. Besides, if you injure yourself further, you’d be a liability.”

  Randi shook her head. “Can’t argue. Don’t know how. I don’t … don’t want to be baggage.”

  “I’d hardly call it being baggage,” Nikhil sniffed. “Enforced rest under medical orders. Now, if you’re going to be a professional in your own right instead of Daddy’s little indulgence, you’ll chin up, follow medical orders, and stop wasting time.”

  “Nikhil, dear,” Cathy growled, “get your damn mouth out of my patient’s psyche.”

  Nikhil was exactly right, I thought, but I wanted to slug him for saying it that way.

  “Very well,” Nikhil said, evenly ignoring the feeling in Cathy’s voice, “I regret the personal reference, Randi, but the point stands. Please don’t be difficult.”

  Lacking support from anyone else, Randi’s position was hopeless. She suffered herself to be taped onto a litter improvised from the same tent braces, sheets, and tape we had used earlier to make her wings.

  This done, Nikhil turned to me. “You mentioned leading a pitch?”

  Fortunately, the route started out like a one-third scale version Nikhil’s Smokestack. It wasn’t a straight shot, but a series of vertical caverns, slightly offset. Sam rocketed ahead with a line, anchored himself, and reeled the rest of us up. The short passages between caverns were the typical wide, low cracks and I managed them without great difficulty, though it came as a surprise to discover how much rock and ice one had to chip away to get through comfortably. It was hard work in a pressure suit, and my respect for Nikhil and Randi increased greatly.

  At the end of the last cavern, the chimney bent north, gradually narrowing to a funnel. We could hear the wind blow by us. At the end was a large horizontal cavern, dry, but full of hoar crystals. The rift was clearly visible as a fissure on its ceiling. That was for tomorrow.

  The ethane level was down enough for us to forego decontamination, and before we turned in we congratulated ourselves for traversing sixty percent of the rift in less than half our allotted time.

  As we turned in, Randi said she had feeling in her fingers and toes again. Which meant she must have had no feeling in them when she was demanding to lead the pitch this afternoon.

  She’s sleeping quietly, it’s only midnight, and I am going to get my first good night’s sleep in a long time.

  Day eleven is thankfully over, we are all exhausted again, and bitterly disappointed.

  The day started with a discovery that, under other circumstances, would have justified the entire expedition; the mummified remains of aliens, presumably those who had left the strange piton. There were two large bodies and one small, supine on the cavern floor, lain on top of what must have been their pressure suits. Did they run out of food, or air, and give up in that way? Or did they die of something else, and were laid out by compatriots we might find elsewhere?

  They were six-limbed bipeds, taller than us and perhaps not as heavy in life, though this is hard to tell from a mummy. Their upper arms were much bigger and stronger than their lower ones and the head reminded me vaguely of a Panda. They were not, to my memory, members of any of the five known spacefaring races, so, in any other circumstances, this would have been a momentous event. As it was, I think I was vaguely irritated at the complication they represented. Either my sense of wonder wasn’t awake yet, or we’d left it behind, a few geode caverns back.

  “How long?” Cathy asked Sam in a hushed voice. She, at least, was fascinated.

  “If the present rate of dust deposition can be projected, about two hundred and thirty thousand years, with a sigma of ten thousand.”

  “Except for the pressure suits, they didn’t leave any equipment,” Nikhil observed. “I take that to mean that this cavern is not a dead end—as long as we do press on. You have your images, Sam? Good. Shall we?”

  We turned to Nikhil, away from the corpses.

  “The vent,” he said, looking overhead, “is probably up there.”

  “The ceiling fissure is an easy jump for me,” Sam offered. “I’ll pull the rest of you up.”

  We got on our way, but the rift quit on us.

  Once in the ceiling caves, we found there was no gas flowing that way, the way where Sam’s seismological soundings, and our eyes, said the rift was. We chanced the passage anyway, but it quickly narrowed to a stomach-crawling ordeal. Three kilometers in, we found it solidly blocked and had to back our way out to return to the cavern. Another passage in the ceiling proved equally unpromising.

  “Quakes,” Nikhil said. “The rift must have closed here, oh, a hundred million years ago or so—from the dust.” So, when dinosaurs ruled the Earth, Miranda had changed her maze, no doubt with the idea of frustrating our eventual expedition in mind.

  Finally, Sam found the outlet airflow. It led back to the north.

  “I hereby dub this the Cavern of Dead Ends,” I proclaimed as we left, with what I hoped was humorous flourish.

  Surprisingly, Nikhil, bless his heart, gave me one short “Ha!”

  Randi was not to be denied today, and took the first pitch out in relief of Nikhil. But she soon tired, according to Cathy, who was monitorin
g. I took over and pushed on.

  The slopes were gentle, the path wide with little cutting to do, and we could make good time tugging ourselves along on the occasional projecting rock and gliding. We took an evening break in a tiny ten-meter bubble of a cavern and had our daily ration crackers, insisting that Randi have a double ration. No one started to make camp, a lack of action that signified group assent for another evening of climbing and gliding.

  “We are,” Sam said, showing us his map on our helmet displays, “going to pass very close to the upper end of Nikhil’s Smokestack.” No one said anything, but we knew that meant we were backtracking, losing ground.

  There was a final horizontal cavern, and its airflow was toward the polar axis. We could pretty much figure out what that meant, but decided to put off the confirmation until the morning. I’d once read a classic ancient novel by someone named Vance about an imaginary place where an accepted means of suicide was to enter an endless maze and wander about, crossing your path over and over again until starvation did you in. There, you died by forgetting the way out. Here, we did not even know there was a way out.

  The beginning of day twelve thus found us at the top of Nikhil’s Smokestack again, on a lip of a ledge not much different than the one about a kilometer away where we had first seen it. We were very quiet, fully conscious of how much ground we had lost to the cruel calendar. We were now less than halfway through Miranda, with less than half our time left.

  Sam circled the top of the Smokestack again, looking for outlets other than the one we had come through. There were none. Our only hope was to go back down.

  “Do we,” I asked, “try the inner river, or try the other branch of Randi’s River and fight our way through the Boiling Sea?”

  Nikhil, though he weighed less than three newtons, was stretched out on the ledge, resting. His radio voice came from a still form that reminded me in a macabre way of the deceased aliens back in the Cavern of Dead Ends.

  “The Boiling Sea,” he mused, “takes the main flow of the river, so it should have an outlet vent. It is obviously in a cavern, so it has a roof. Perhaps we could just shoot a piton up at it, blindly.”

  But I thought of Nikhil’s Smokestack—a blind shot could go a long way in something like that.

  “Sam could fly up to it,” I offered. “If we protect it until we reach the Boiling Sea’s surface, it could withstand the momentary exposure. Once at the ceiling, it could pull the rest of us up.”

  Cathy nodded and threw a rock down Nikhil’s Smokestack, and we watched it vanish relatively quickly. Dense, I thought, less subject to drag. As it turned out, I wasn’t the only one with that thought.

  “Look what I have,” Randi announced.

  “What” was a large boulder, perhaps two meters across, and loose; Randi could rock it easily, though it must have had a mass of five or six tons. “Bet it doesn’t fall like a snowflake,” she said as she hammered a piton into it.

  Even in the low gravity, it took two of us to lift it over the edge.

  Two hours later, about a kilometer above Cathy’s Rock, we jumped off into the drag of the slipstream and watched the boulder finish its fall. It crashed with a resounding thud, shattered into a thousand shards, most of which rebounded and got caught in the chimney walls. We soon reached local terminal velocity and floated like feathers in the dust back to the place we had first departed three days ago.

  Cathy decided that Randi was in no shape for another immersion and didn’t think I should risk it either. I did have a few red patches, though I’d spent nowhere near as much time in the ethane as Randi. We looked at Nikhil, who frowned.

  Cathy shook her head. “My turn, I think.” But her voice quavered. “I’m a strong swimmer and I don’t think Nikhil’s done it for years. You handle the spray, Wojciech. You don’t have to cover every square centimeter, the fibers will fill in themselves, but make sure you get enough on me. At least fifteen seconds of continuous spray. Randi—I can’t hold my breath as long as you. You’ll have to help me get buttoned up again, fast.”

  When all was ready, she took several deep breaths, vented her helmet and stripped almost as quickly as Randi had. This, I thought as I sprayed her, was the same woman who panicked in a tight spot just over a week ago. The whole operation was over in a hundred seconds.

  The pulley I’d left was still functional, but that would only get us to the branch in the passage that led to the Cavern of Dead Ends. From there on, Cathy would have to pull us.

  It was not fun to be sealed in an opaque, uninflated tent and be bumped and dragged along for the better part of an hour with no control over anything. The return of my minuscule weight as Sam winched us up to the roof of the Boiling Sea cavern was a great relief.

  Randi, Nikhil, and I crawled, grumbling but grateful, out ot the tent onto the floor of the cave Sam had found a couple of hundred yards from the center of the domed roof of the cavern. The floor sloped, but not too badly, and with a milligee of gravity it scarcely mattered. I helped Nikhil with the tent braces and we soon had it ready to be pressurized. Sam recharged the pallet power supplies and Randi tacked a glowlamp to the wall. Cathy then excused herself to get the Exoderm out of her tightsuit while we set up the other tent.

  Work done, we stretched and floated around our little room in silence.

  I took a look out the cave entrance; all I could see of the cavern when I hit my strobe was a layer of white below and a forest of yellow and white stalactites, many of them hundreds of meters long, on the roof. The far side, which Sam’s radar said was only a couple of kilometers away, was lost in mist.

  Then I noticed other things. My tightsuit, for instance, didn’t feel as tight as it should.

  “What’s the air pressure in here?”

  “Half a bar,” Sam responded. “I’ve adjusted your suits for minimum positive pressure. It’s mostly nitrogen, methane, ethane, and ammonia vapor, with some other volatile organics. By the way, the Boiling Sea is mainly ammonia; we are up to two hundred and twenty Kelvins here. The ethane flashes into vapor as it hits the ammonia—that’s why all the boiling.”

  Miranda’s gravity was insufficient to generate that kind of pressure, and I wondered what was going on.

  “Wojciech,” Randi whispered, as if she were afraid of waking something. “Look at the walls.”

  “Huh?” The cave walls were dirty brown like cave walls anywhere—except Miranda. “Oh, no hoar crystals.”

  She rubbed her hand on the wall and showed me the brown gunk.

  “I’d like to put this under a microscope. Sam?”

  The robot came quickly and held the sample close to its lower set of eyes. I saw what it saw, projected on the inside of my helmet.

  “This has an apparent cellular structure, but little, if any structure within. Organic molecules and ammonia in a kind of jell.”

  As I watched, one of the cells developed a bifurcation. I was so fascinated, I didn’t notice that Cathy had rejoined us. “They must absorb stuff directly from the air,” she theorized. “The air is toxic, by the way, but not in low concentrations. Something seems to have filtered out the cyanogens and other really bad stuff. Maybe this.”

  “The back of the cave is full of them,” Randi observed. “How are you?”

  “My skin didn’t get as raw as yours, but I have a few irritated areas. Physically, I’m drained. We’re going to stop here tonight, I hope.”

  “This is one of the gas outlets of the Cavern of the Boiling Sea,” Sam added. “It seems to be a good place to resume our journey. The passage is clear of obstructions as far as I can see, except for these growths, which are transparent to my radar.”

  “They impede the airflow,” Nikhil observed, “which must contribute to the high pressure in here. I think they get the energy for their organization from the heat of condensation.”

  “Huh?” I wracked my memories of bonehead science.

  “Wojciech, when a vapor condenses, it undergoes a phase change. When ethane vapor turns
back into ethane, it gives off as much heat as it took to boil it in the first place. That heat can make some of the chemical reactions this stuff needs go in the right direction.

  “Are they alive?” I asked.

  “Hard to say,” Cathy responded. “But that’s a semantic discussion. Are hoar crystals alive? There’s a continuum of organization and behavior from rocks to people. Any line you draw is arbitrary and will go right through some gray areas.”

  “Hmpf,” Nikhil snorted. “Some distinctions are more useful than others. This stuff breeds, I think. Let’s take some samples, but we need to get some rest, too.”

  “Yes, dear.” Cathy yawned in spite of herself.

  In the tent, Randi and I shared our last regular meal; a reconstituted chicken and pasta dish we’d saved to celebrate something. The tent stank of bodies and hydrocarbons, but we were used to that by now, and the food tasted great despite the assault on our nostrils. From now on, meals would be crackers. But we were on our way out now, definitely. We had to be. Randi felt fully recovered now and smiled at me as she snuggled under her elastic sheet for a night’s rest.

  It must have been the energy we got from our first good meal in days. She woke me in the middle of our arbitrary night and gently coaxed me into her cot for lovemaking, more an act of defiance against our likely fate than an act of pleasure. I surprised myself by responding, and we caressed each other up a spiral of intensity which was perhaps fed by our fear as well.

  There are the tidal forces near Randi’s event horizon; she is not just strong for a woman, but strong in absolute terms; stronger than most men I have known including myself. I had to half-seriously warn her to not crack our low gravity-weakened ribs. This made her giggle and squeeze me so hard I couldn’t breathe for a moment, which made her giggle again.

  When we were done, she gestured to the tent roof with the middle finger of her right hand and laughed uncontrollably. I joined her in this as well, but I felt momentarily sad for Nikhil and Cathy.