IGMS Issue 18 (6 page)

There were several ways to answer that, so I just stayed silent.

"Take a look at these two rocks. Tell me what you see."

She'd laid out two samples. One white, the other gray.

I said, "One is mostly ice. The other some kind of basalt. Just like every other rock on this moon."

"Exactly! That's what's so remarkable."

I knew what she was getting at, of course, why geologists were so obsessed with Miranda. I just didn't care. I was interested in the canyon's present, not its past.

"Do you remember that time we hiked up Ophir Peak? When I spotted Uranus in my scope and told you all about the mystery of Miranda?"

I remembered Ophir Peak. A small mountain overlooking Mars' Candor Chasma. Spectacular views. I'd spent months exploring the hidden nooks and caves of that canyon, before the mining bots moved in.

"Well," Shelley said, "nothing's changed. It's still a mystery. We've now imaged every moon in the solar system, and they all show some kind of recognizable geology -- young rocks on top of old, or at least patterns. But Miranda is different. It's a jumbled, jagged mish-mash of ice and rock, as though someone broke it apart with a hammer and glued the pieces back together."

Wil and Katherine had finished their break and were now heading back toward the descent rope. I'd locked a splicer to the line so they couldn't leave without me, but still.

"Time to go," I said. Shelley scooped up her samples and stood. I gripped her arm, not to help her up, but to keep her from flying off her feet, then steered her to the rope.

"This canyon is important, Lance. It's not just another of your trophy climbs. It descends ten percent of the way to the core. If I can collect samples from the bottom, we might finally learn what happened to this moon."

I cut in front of Wil, beating him back to the rope. He gestured grandly toward the canyon floor, grinning. You first.

I stayed on Shelley's private frequency. "This isn't Mars, Shelley. If you want to reach those depths without running out of air, then keep my pace. Sample all you want from the ledges, but don't stop your descent. Understood?"

"Fair enough," she said.

I unlocked the splicer, hooked in my carabiner, and stepped off the ledge. The others followed.

For the next several legs, we made better time. Shelley slowed to take mass spec data but didn't chisel any samples, except during breaks. She was also getting more proficient at using friction to control speed, rather than squeezing the rope and jerking to a stop. We settled into a steady, quiet rhythm.

I'd positioned Shelley between me and Wil on the line so I could keep a closer eye on her. As I watched her slide through the inky darkness, I found myself doing something I rarely do: thinking about the past.

I met Shelley sixteen years ago, back when I worked for MME, the Martian Mining Enterprise, testing new pressure suits for extended external operations. The job was an excuse, really, to explore Mars' untouched equatorial chasmas before they were inevitably mapped and defiled. Shelley was a young geologist stationed at the colony, part of MME's science outreach. A week after she arrived, she loped into my lab, a pressure suit draped over her arm.

"They call you the Martian Magellan," she said.

I had both arms deep inside the polymer press, stretching out my latest prototype. I turned off the machine and glanced up. She looked young -- younger than her years, even -- with a pleasant shape and an eager smile. She gripped an edge of the plastic wall, still unsteady in the Martian gravity.

"They tell me you've been up the Tharsis volcanoes, down Melas and Cando Chasmas, only you never tell anyone where you're going or where you've been."

"I'm testing prototypes."

She smiled, knowingly. "When do you head out next?"

"Day after tomorrow." I pointed at the suit taking shape in the press. "As soon as this congeals."

"Take me with you. I'm fully certified for exterior. On your suits, in fact."

I took her on a three day jaunt across Juventae Chasma, a deep lake bed below the Ophir Planum. I'd traversed it once before, but the colored canyon walls and hidden caves were worth a second look. After the trip, we began sharing quarters.

For awhile, the relationship was satisfying. We were compatible physically, and she seemed to understand my need to see new things first. She only accompanied me on short range outings, and when we'd discover a hidden cave, she'd let me venture inside first, alone, and only follow if I called for her.

Over time, though, her demands changed. She began requesting that I bring back rock samples from my excursions, something she knew I wouldn't do. When I refused, she stuck geology texts in my inbox, with pithy notes about the "rush" she gets from a scientific discovery. She dropped hints about degree programs back home, near her family's compound in Colorado.

Eventually it ended, like they all end. MME began experimenting with exploration bots, tiny crawlers set loose in the canyons, scurrying, imaging, sampling every square inch. I raced to stay ahead of them, my excursions taking me farther and farther from the colony. Shelley chafed at my extended absences, the long periods of silence. Her demeanor grew bitter, demanding.

Through my contacts at MME, I learned they were building a new base on Ganymede, in the Jovian system. They needed a scout, someone comfortable in the lunar gravities of the Galilean moons. They promised there would be no exploration bots, at least for a few years. I signed on. I sent Shelley a short note from the transport craft, after we'd cleared the orbit of Mars.

By the time we left the canyon's fifth ledge, halfway down, we were back on schedule. Shelley had taken dozens of samples from the first five ledges, muttering that the rocks were still uniform, that she needed more data, but she kept her promise not to stop. Wil and Katherine had stayed dutifully up rope, behind Shelley, remaining silent.

Somewhere between the fifth and sixth ledges, my radio clicked on. It was Shelley, on the private frequency. "You know, Lance, I've tracked your career all these years, since that night you left Mars. Penetrating those caves on Ganymede, the ice cliffs on Europa, that Io volcano thing."

I can't say I'd followed Shelley's career, but I did look her up after getting her message about the canyon. After Mars, she'd returned to Earth, where she'd become a professor. She'd published dozens of papers about the geology of the Martian chasmas, then a few about the Galilean moons of Jupiter and Saturn's Enceladus. Recently, she'd entered the Great Debate about Miranda. Married once, briefly, no children.

"I heard," she went on, "that MME fired you for hiding deposits from them."

That was true. Even now, their bots had only found a fraction of the caves I discovered on Ganymede and Amalthea.

"Are you still in the Saturn system?" she asked. "Living with those crazy homesteaders in Herschel crater?"

"They give me space," I said. "And Saturn has dozens of moons to explore."

"So what will you do when the miners settle Saturn? Move out here? To the Kuiper belt? Sail off to interstellar space?"

I pointed my helmet light straight down and narrowed the beam. I could see only the rope, undulating from side to side like a dancing snake. At the limit of my headlamp, it disappeared into inky abyss. The canyon's floor was still too distant to see. I increased speed to three meters per second.

Shelley's laugh broke the silence. "Don't you get it, Lance? You're not exploring, you never have been. You're running. You've always been running."

After I'd left Mars, Shelley had sent me a series of letters. The first were pleas to join her, back on Earth. When I didn't respond, the letters turned angry, analytical. I was a junky, she said, hooked on exploration, too selfish to care about anything or anyone else. There were more choice words, but I stopped reading the letters, and after a few months, she stopped sending them. But now, to my annoyance, she was at it again.

"You know how this ends, don't you? This running of yours? It ends with you dead, alone, buried in some hidden cave, or on the bottom of some frozen canyon."

I clicked on my radio, to tell her that I could think of worse fates, but Wil cut in on the common frequency.

"Uh, boss, your girlfriend has stopped again. She's got her chisel out. We don't have unlimited air, you know."

I clicked back to Shelley's private frequency. "Dammit, Shelley, we had an agreement."

"Climb back up here, Lance. You have to see this." She sounded out of breath.

I squeezed the rope until my downward progress stopped, then pulled gently, floating back up toward the others.

She had her headlamp trained on a small rock in the wall. It was smooth and black, about the size of her hand. And reflective, which seemed impossible on this cold, dusty world. It was beautiful, I realized. Like a gem.

"What is it?" I asked.

"No idea. It's got carbon in it. And some silica, maybe, but my sensors don't recognize the structures. I've never seen anything like it. Might be from the moon's core."

She beat at the wall with her chisel, trying to pry the gem free.

"Leave it," I said.

"Maybe you could retrieve it on the way up," offered Katherine, using her silky voice. "If we have time."

Shelley continued hammering. "If I do nothing else today, I'm taking this sample."

There was a jostling of bodies, then Wil was next to Shelley, trying to pass her on the line. "We'll wait for you at the next ledge," he said.

I blocked him. "No! I go down first, remember? If you pass me, I swear I'll cut the line." Wil stopped. Katherine stopped behind him, her arm around his waist.

"Shelley, how long will it take you to get this sample?"

"Ten more minutes."

"You've got eight. And to make up the time, we'll skip the next three ledges and go straight to the ninth. Clear?"

Shelley nodded. Wil and Katherine spoke on their private frequency, then opened a line to me. "That's reasonable," said Katherine. "We're happy to wait."

Ten minutes later, the gem was free. Shelley held it in front of her helmet light, turning it around in her hand.

Its entire surface was smooth and black, reflecting Shelley's headlamp like a mirror. Its front end, the part that had been buried in the wall, was sharp, pointed, with flat sides, like a cut diamond. Shelley held it out toward me. I shook my head. She labeled it and dropped it into her sample bin.

We continued down the rope.

I increased our speed to four meters per second, coasting past the six, seventh, and eight ledges, heading towards the last.

We saw more of the black gems. They were getting larger, too--I passed one longer than my arm, jutting out from the wall like a spear. All were wedged into the wall at an angle, their smooth back ends pointed downward toward the canyon floor. Whatever they were, they'd come from below.

Shelley asked twice to stop, but I ignored her and continued downward. When we passed the eighth ledge, she buzzed me again. I tapped my radio, so she knew I could hear her, but I didn't respond. The canyon was getting interesting.

It widened as we descended, something Shelley's crude radar map hadn't resolved. And there was a curvature to the walls, as though we were entering a bowl, or a crater.

The mysterious gem shards were everywhere. Most were still black, but I'd spotted a few reds and a translucent one that refracted my headlamp into a rainbow -- an astonishing sight twenty kilometers below ground on a gray, frozen moon.

We reached the ninth and final ledge, a mere three hundred meters from the bottom. We'd made up all the lost time, so I locked the splicer to the descent line, shuffled to the rear of the ledge underneath the overhanging wall, leaned back, and looked up.

It's a compulsion that I have. Whenever I find a new cave, I stop, look up, and picture the first cave I ever explored.

I grew up in Northern Arkansas, in a crowded home near a patch of dark woods. Those woods captivated me. Summers, I'd slip away from my six older siblings and explore, wooden staff in hand, imagining myself to be Jacques Cartier or Ernest Shackleton.

One June afternoon, I came across a thin stream that disappeared into the side of a hill. I dug through bushes and dirt with my staff, made an opening, and slithered through on my belly. The ground fell out from under me and I slid downward over wet rock, crashing to rest in a muddy puddle at bottom.