Mars Crossing

by Geoffrey Landis

  Purple? Tana thought. Amethyst?

  "Wait, further in the crystals are all white, kind of translucent. Doesn't look like quartz, it's not six-sided. Four-sided crystals."

  "Hold on," Estrela said. "Four sided-crystals? You said four-sided?"

  "Squares and rectangles. It looks familiar."

  "I bet it does," Estrela said. "It's halide. Salt."

  "Salt?" There was a long pause. "You know, I think that's it. Salt. The cave is covered in salt."

  9

  A DESTINY ON MARS

  Tana was not extravagant or showy about her religion, but her family had been good Methodists, went to church every week without fail, and she had never questioned her faith. Her faith was just there, something that cradled her and supported her through the hard times, something that made her know for sure that her life had a meaning and a purpose, that even if nobody else loved her, she was loved by God, and that was enough.

  It never would have occurred to her to articulate it, but her urge to explore was, for her, inseparable from her unquestioned religious faith. She saw exploration as a way to see the depths of the beauty of God's creation.

  Tana had not always been interested in space exploration. She had gone to medical school because it seemed to be something difficult, something that promised hard problems for her to solve, and she felt most alive when she was meeting challenges.

  That changed in the spring of her first year of medical school. There was a talk on the campus sponsored by the Mars Society, and she had almost not gone at all. It was certainly far removed from studying medicine. In the end that was why she had gone, because she needed to take a break; she wanted to get away from the medical school and the arrogant pricks who were her fellow students, and the lecture was cheaper than a movie.

  They had brought in an astronaut to speak. He was a Canadian, younger than Tana had expected, a boy with long dark hair tied in a ponytail.

  Much later, when she spent two years training with him, she would never mention that she had first seen Ryan Martin at a lecture at Case Western Reserve. She doubted that he realized she had met him before; the auditorium was packed, and she was in back, and who was she then, anyway? Just another anonymous face in the crowd. And she would certainly never admit that, once long ago, she'd had an intense puppy crush on him.

  But he had spoken with such evangelistic fervor. Mars, he told them, was not an impossible target. With clever planning, it could be done. Should be done. He showed slides and talked about evolution, and about human destiny, and about how, someday, humans would not only have colonies on Mars, but they would terraform the planet. Mars is cold and dry and lifeless, but with coaxing, with engineering, it could be warmed, could be made into an inviting, living planet. And a trip to Mars need not be expensive. It all depends, he told them, on the ability to make rocket fuel on Mars, and he laid out all the elements of the Mars expedition, almost exactly the way that, fifteen years later, it would actually happen. "And you can go," he said. He pointed into the crowd. "You." He pointed a different direction. "You, too." And then he pointed at the back of the crowd, directly at Tana. "And you."

  And Tana had been hooked. In college she'd set aside her science fiction as foolish fantasies of childhood. She'd never considered becoming an astronaut before, hadn't even considered the possibility, but now she was ready to go to Mars.

  Her infatuation with Ryan Martin didn't last; he left the campus the next day, and she never even spoke with him. Later, when she married Derrick, she had already long forgotten that she'd ever even briefly had a crush on a lecturer. But the dream of going to Mars had been ignited, and it was a flame that would never, quite, go out.

  10

  CAVE

  Tana was the next down, and in fifteen minutes she was standing on the smooth floor of the cave and added the beam of her light to Ryan's. The crystals were indeed salt, she realized. Even the purple ones; eons of exposure to cosmic rays had slowly infused color into the crystals nearest the edge of the canyon.

  Except for the salt crystals, the cave was almost entirely featureless, with a smooth flat ceiling, and an equally even floor, devoid of stalactites or stalagmites or any other cavelike geology.

  The explanation, Tana realized, was that there must once have been immense salt flats here, remnants of some ancient ocean bed that had long since dried up, leaving only the salt behind. And then, over the ages, the salt flats had been buried under ash and lava from the eruptions of the great Tharsis volcanoes. Then, when the Valles Marineris had been carved like a knife-cut into the crust of the planet, exposure to water had dissolved away the salt layer, leaving a wide, horizontal cave in the side of the canyon, ten feet high and hundreds of miles, perhaps thousands of miles long.

  How extensive was the salt layer, Tana wondered? Had the entire planet been covered with an ancient ocean? Did the entire planet have a buried layer of salt, hidden under the crust? Or was it just this area near the equator? And, more important, had the ancient ocean ever developed life?

  She wanted to stay, to explore the caves, to investigate the rocks with a microscope to search for possible microfossils, but it was impossible. They had to move on or die.

  But it wouldn't hurt for her to look just a little bit. In fact, it made sense for the others to rappel down before she moved on.

  The crystals—Ryan hadn't mentioned how big they were. Here was a cluster of crystals, each one the size of a milk carton, with edges so rigorously square that they looked as though they had been machined; another one was a perfect octahedron, like some modern sculpture of glass. Were they all salt? The top layer certainly was, but it looked like there was something else underneath, something a whiter color, almost a milky blue. She scraped off the top layer. Yes, it was something softer, definitely different, not just rock salt. There was a mass spec back at the rockhopper; if she took some samples, they could analyze them later.

  Was it the same all the way back?

  Tana shone her beam into the back of the cave and walked farther to see just how far back it went.

  11

  INTERVIEW

  It was a big conference room, with a faux-mahogany table and upholstered seats that swiveled and tilted. With only two of them in the conference room, it seemed empty. Tana fought the impulse to lean back in the comfortable chair while waiting for the interviewer to speak. She knew she had the credentials; what was important now was not to blow her chances by saying something stupid or giving the wrong impression. She sat up rigidly straight to make it clear she was interested.

  At last the interviewer looked up at her. She didn't know him personally. He was one of many anonymous, well-groomed men in impeccably tailored suits. One of a network of interconnecting country-club acquaintances that—regardless of what the organization charts may imply—held the real power in the center. He said, "Do you think you deserve a spot on the expedition because you're black?"

  "No, sir," Tana said. "A Mars expedition is no place for deadwood. I deserve a position because I'm the best qualified for the spot."

  He looked back down and flipped through her papers again. She could see her application form stapled to the top, then transcripts, then employment files. "Hmmm," he said, without looking at her. "Says here you did your residency in an emergency room ... Still up to date on your skills?"

  "Yes, sir. I volunteer at the free clinic every other week."

  "Well, that counts for something. We'll need quick response if we have an emergency. But you're not the only one with ER experience, you know. How's your exobiology?"

  "I'm working with Feroz and Papadopoulos," she said. "It's in there."

  She suddenly had to pee. She couldn't possibly need to; she knew better than that. Before she went to an interview, especially one as important as this, she always hit the ladies' room. But it sure felt as if she suddenly had a desperate need.

  "Yes, Feroz and Papadopoulos ... good credentials." He looked up at her. "How's the work going?"

&nb
sp; They were cataloging stereoisomers found in Antarctic meteorites and in meteoritic dust samples gathered from high-altitude airplanes. The point was to establish whether a chiral asymmetry existed in samples from the primordial nebular material, and, if so, whether it had been modified in the subsequent five billion years of solar system evolution. If they found conclusive evidence that chiral asymmetry predated life on Earth, it would be a landmark achievement in exobiology, since so far the chiral nature of organic compounds on Earth was a sure signature of life. But so far, like the signs of life in Martian meteorites, their evidence remained tantalizingly suggestive, but inconclusive.

  She resisted the urge to shrug. "It's going well," she said.

  "You like the lab work?"

  "I love it," she said. And, to her own surprise, she did. She had started working with Feroz simply as a way to get some exobiology publications on her resume, but she found that she liked being back in a laboratory. It was painstaking, and ten seconds of inattention could ruin ten hours of work, but she found that she liked the challenge.

  "Good. I'm sure you do. But all that's not worth a hill of beans, really, is it?"

  Obviously, he wanted some response from her here, and she didn't know what it was. Play it cool. "I'm not quite sure what you mean."

  "What matters here is just one thing. Can you handle the public?"

  "Yes, I think so. In my application, I have listed—"

  "I don't care what's in your file. Everybody has a great file." He flipped the file of papers away from him, and it skidded across the table. "I've read two hundred great files. What I care about is, can you handle the public?"

  Time to be firm. "Yes, sir, I can."

  "Well, good. I hope you can." He looked at his watch and then stood up. Was the interview over? Tana hastily stood up as well.

  He walked toward the door at the far end of the conference room, and then turned back to look at her. Perhaps there was a slight smile on his face; if there was, it was the first trace of any emotion she'd seen him express. She wished she could remember his name. He had introduced himself to her when the interview had started, but she hadn't been able to place the name.

  "As you may know, on Tuesday afternoons we invite elementary school classes to tour the center. Today we've got a class of fifth graders on a field trip all the way from Tulsa, Oklahoma. We've promised them a special lecture. You're it." He looked at his watch. "You're going to tell them about Mars."

  He opened the door. It led to a main lecture hall, with every seat occupied by fidgeting, talking, wrestling, gum-chewing, airplane-throwing, shouting, sleeping, bored children. "They've been waiting about five minutes now, they're probably getting a little restless. There's about two hundred of them, I'd say."

  Yikes.

  He turned to her, and this time it was quite clear, he was smiling. "You said that you're good with the public, did you now? Well, here you have a chance to demonstrate. Don't let's keep them waiting, shall we?"

  Now she really had to pee. She ignored it, took a deep breath, and walked out. Get their attention now, she thought, or else lose it.

  She found the microphone and tapped it. For a moment, just a moment, the din of conversation in the room let up. "Hi," she said, and smiled. "I'm Tanisha Jackson. I'm a biologist here at NASA Johnson, and I'm here to tell you all those things about space biology that you haven't quite had the nerve to ask yet. Like, for example, how you go to the bathroom in space."

  There was a giggle, first just one, then a bunch all at once, and then outright laughter, and she knew she'd caught their attention.

  "But, first, maybe you'd like to hear me tell you a little bit about Mars."

  12

  PAUSE IN THE DESCENT

  Captain Radkowski stopped briefly at the slot cave—it was, in fact, a convenient ledge to pause on—but did not unhook from the superfiber to join Tana and Ryan at the back wall of the cave marveling over the wonders of salt. From the radio reports, he knew that they had determined that the slot in the side of the canyon wall extended back about a hundred feet and then came to an end.

  "It's completely smooth," Ryan's voice said. "Seems almost polished. A blank white wall."

  "I wonder how far the salt layer continues?" Tana.

  "Don't think we can tell without a drill." Ryan. "A long way, I bet."

  "Hundreds of miles?"

  It was not of great interest to him. Radkowski was more worried about getting the crew down the cliff to the rockhopper, and making sure it was secure for the long traverse to the bottom of the canyon.

  He thought about reprimanding Ryan Martin for slowing down the expedition by stopping to explore the cave, but decided that it was understandable. They had, after all, come to Mars to explore. He would talk to Ryan privately later, caution him that regardless of what they found, getting north as fast as possible had to remain their first priority.

  Before descending from the cave level, he checked his rappelling line and safety line attachments again. Both good. He pulled at the superfiber. "On belay," he said.

  His anchor points, for both the rappelling line and the safety line, were still up at the top. From his radio, Trevor's voice said, "On belay."

  He looked down—it was a long drop, still most of a vertical mile of drop—and then stepped backward off the edge. The superfiber held him, and then, without warning, it gave, and he was in freefall.

  Shit. "Falling," he called. "Tension!"

  The safety line caught, and he swung out from the cliff, twisted around awkwardly.

  And then the safety line broke.

  He started to tumble, and instinctively he assumed the skydiver's position, arms spread, legs in a V. "Tension," he shouted, but he knew that it wasn't going to do him any good. The line had snapped, and there was nothing between him and the ground but two thousand feet of thin Martian air.

  It took him a long time to fall.

  13

  ON STATION

  Tana Jackson's selection for the medical position on the Mars mission pushed her to the top of the priority list for assignment to the space station. Her name would not be publicly announced for the Mars billet until after she had been tested in orbit. None of the crew had been announced yet. They wanted to see how she worked out in microgravity, how well she got along with the station crew when she was confined in a tin can, with no new faces to see, with nowhere to go to get away. Her nomination to fly on the Mars mission was a recommendation, not a right; at any time she could be reassigned if they decided she might not work out.

  The orders for her to start training for a ninety-day shift on the space station arrived the next day. At the same time, she was directed to take refresher courses in epidemiology, most importantly to memorize the medical details of the reports of the three independent review panels that had evaluated the Agamemnon disaster. She was also expected to become an expert on the hypothetical biology of Martian life. And, in addition to all of this, she was to appear cheerful and knowledgeable whenever the press needed a warm body to interview.

  She began to train with the microgravity emergency medical kit, until she could unerringly find each piece upside-down and blindfolded: tracheotomy tubes, laryngoscope, oxygen mask, miniature oxygen tank, compresses, syringes, dressings, adhesives, scalpel, stethoscope, blood oximeter.

  She had never worked harder in her life. The launch to the space station, when it came, seemed almost like a vacation. She was so excited that she barely noticed the launch, and only when she saw her notepad floating out of her pocket did she realize, I'm really here; I'm in zero gravity. I made it.

  Tana's billet was to be the blue-shift medical officer, and in her spare time, a biology research technician and an experimental subject. The bio labs always needed both technicians and subjects.

  She liked being on space station. Ft was crowded and noisy and confusing. It was remarkably easy to get confused, and even—despite its small size—momentarily lost. The familiar route from one module to another t
hat you've memorized as a left turn would, if you happen to be flipped, mutate into a right turn, or even an up or down turn. Compartments that she thought she knew completely suddenly became completely unfamiliar when she came in with a different orientation, and the floor had become the ceiling. In a way, it was as if the space station were far larger on the inside than its mere volume, when every floor was also a wall and a ceiling.

  On her arrival at the space station, Brittany and Jasmine, two crew members who were already old hands on the station, were detailed to give her the orientation. Brittany was big-boned, tall and square and blonde; Jasmine was small and dark, with a round face. They acted as smoothly as if they had been working with one another since they had been born.

  "It's big and ugly and smelly," Brittany said, waving her hand at the station.

  "Isn't it just," Jasmine said. "God, don't you love it here?"

  "Yeah," Brittany said. She looked at Tana. "Girl, you may not know it, but the moment you get back down, let me warn you, you're going to start scheming how to get back up here."

  "Home," Jasmine said. "Come on. I think there's nobody in the number two biology lab." She contorted her body, jackknifed, and with a sudden jerk, was facing the opposite direction. Tana had no idea how she had accomplished it without touching a wall. "Let's go over there, and we can"— she winked at Tana—"give you a briefing in private."

  Tana already knew about the zero-gravity rite of passage, or at least the outline of it. The grapevine at the center had been pretty explicit. She didn't bother to try Jasmine's maneuver, but instead pushed off the wall to follow.

  As the newcomer, Brittany explained, a tradition as old as the space station itself gave her the jus primae noctis, the right to choose who she wanted for the first night, any one of the seasoned crew.

  "And it doesn't have to be one of the men, either," Jasmine said, and winked. "If you go that way."