Mars Crossing

by Geoffrey A. Landis

Kaitlyn was, he discovered, the smartest person he had ever met, and he was eternally baffled by what it was she saw in him. Sex, to her, was playful. They would take her Toyota Corolla on long weekends up to Maine, and they would take an old logging road far into the woods and camp, making love far into the night. “Let’s try something new,” was her catch-all phrase. Or they would tryst on one of the rooftops of the Institute, the altitude and the fear of somebody coming across them adding to the thrill of sex.

  One summer they spent in urban spelunking. She showed up in his dorm room one day with two flashlights and a crowbar. The game was, find a manhole and see what was underneath it. Sometimes it was nothing. Sometimes it led to tunnels and pipes that seemed to go everywhere in Cambridge. “Hmm, guess you’re not claustrophobic,” Kaitlyn had said the first time he got stuck and had to wait in the dark while she went to fetch a block and tackle to pull him out. “You should be an astronaut.”

  She was the first girl he ever fell in love with. A week after they both graduated—he in computer science, she in mathematics—Kaitlyn asked him to marry her. He hadn’t even told his parents yet—he was going to spring it on them when he went back home for the American Thanksgiving holiday when a pickup truck sideswiped her going around a curve, and her Corolla fishtailed and hit a lamppost.

  It was hard for him to believe that she was really dead. For years afterward he would wake up with some thought in his head, and think, I’ll have to remember that to tell Kaitlyn.

  It took him a long time to get over her. He moved back to Toronto and got a job working on software for an aerospace company. Eventually a quiet, patient girl named Sarah, who he kept running into at work, broke through his reserve and attracted his attention. She worked as a temp, adept at filling in at secretarial jobs when the company was shorthanded, but her real avocation was viola, which she played in a chamber orchestra in Toronto.

  He had never heard a chamber music concert, he finally had to admit to her. He wasn’t really quite sure what kind of music it was. “Well, I guess I’ll just have to show you,” she told him.

  And from then, his weekends were filled with music. Sarah was both patient and had a sense of humor; her musical tastes ran from Beethoven to Weird Al, and she was fond of pointing out little things to him. “Listen there. That’s a cowbell,” she might say, or, “See what you think of this, it’s written for glass harmonica. You play it by rubbing your finger on wine glasses.”

  He got accustomed to her company, and when she went out of town for a performance, he missed her, and hung around his apartment, not knowing what to do with himself.

  They were tentatively beginning to talk about making a commitment for life. The only thing was that Sarah was always so tired. She barely had the energy to go to her concerts. She looked pale.

  She hadn’t always been so tired. When she first started to chat to Ryan over lunchtime, over breaks at work, she had been full of energy. “She’s a real 240-volt live wire,” was how the other engineer in his office described her. Now she could barely make it from breakfast to lunch.

  Ryan took her to a doctor.

  The doctor ordered tests. When the tests came back, he wouldn’t talk about them, but ordered more tests, and a CAT scan. When the new tests were completed, a new doctor came to talk about them, a specialist.

  It was cancer: in her liver and her pancreas, and beginning to spread. The cancer was aggressive and inoperable. The day before Easter, he brought a minister and a wedding license to the hospital, and they were married. Three days later she was dead.

  Twice was enough. He went back to school for three more degrees, one in astronautical engineering and two in computer science, and decided that from then on he would stick to his studies, and would never curse another woman by becoming too close to her.

  7

  BUTTERFLY

  Butterfly didn’t look like anything, least of all like an airplane. It was a pile of thin, transparent foil.

  The Martian atmosphere is more than a hundred times thinner than the Earth’s atmosphere. Even with the low gravity of Mars, flying in the thin air of Mars is a challenge. To fly, an airplane has to have forty times more wing area than an airplane on Earth, or else fly six times faster. Or else weigh forty times less.

  Butterfly did a little of each. Its wing area was absurdly high, by the standards of Earthly airplanes, and it flew at nearly sonic speed; yet despite its high speed and large wing area, it weighed almost nothing. It was constructed out of a monomolecular membrane, a tough plastic sheet so thin as to be almost invisible. The main spars of the wings were pressurized bags, balloon-stiffness providing the rigidity. The fuselage likewise was stiffened by inflation. Ultralight foam ribs formed the wings into a high-lift airfoil.

  “Do you know why they named it Butterfly?” Ryan asked.

  “Because it’s so light and fragile,” Tana said. “Like a butterfly.”

  Ryan smiled. “Nope. Got named when the lead engineer took one look at it, shook his head, and said, ‘Well, it butter fly.’”

  The only item of any real weight was the engine.

  A propeller was almost useless; the tenuous air of Mars is too thin to give a propeller much to grab. A jet engine is pointless; how can you burn carbon dioxide? Instead, Butterfly used a ram-augmented hybrid rocket engine. A feed stream of liquid oxygen was injected into a cylinder of dense rubber and ignited; the burning rubber forms a rocket engine. Rather than just shooting the exhaust product out through a conventional rocket nozzle, additional atmospheric carbon dioxide is collected—the ram part of “ram augmentation”—and mixed into the exhaust stream to augment the thrust.

  The result was a high-power engine that used the thin atmosphere of Mars to increase its thrust.

  This was the vehicle that Ryan Martin examined. His first task was to inflate its wing spars and fuselage with compressed gas; after that he had to fill the engine’s tanks with liquid oxygen. This second task was a tricky problem. The Butterfly had been designed to use oxygen produced from the Mars atmosphere by the same chemical plant that manufactured rocket fuel for the return vehicle. But the fuel manufacturing plant for the Agamemnon expedition was identical to the one that had failed Dulcinea.

  But Butterfly was an airplane, not a rocket. It required less than a tenth of a percent as much liquid oxygen as was needed to launch the return rocket. Consultation with the experts on Earth concurred on the opinion that, for the tiny amount of liquid oxygen needed, Ryan could bypass the main atmosphere compression and Sabatier reactor and just use the electrolysis system and the Stirling liquefier. Taking precautions to avoid stressing the seals that has failed so catastrophically on Dulcinea, he should be able to fill the tanks in a few weeks of operation using only solar power. No more than a few months even under worst-case conditions.

  And so, drop by drop, Ryan fueled his airplane.

  8

  ON ANCIENT SHORES

  They were camped at the shore of what had, long ago, been an ocean. How many fossils were there in that ancient dry ocean bed, Estrela wondered? How far had life come? Had life on Mars emerged from its oceans, only to become extinct as the rivers dried and the planet froze? And what, exactly, had caused the oceans to evaporate and the atmosphere to leak away?

  Estrela was beginning, slowly, to come out of the deep depression that had enveloped her over the last weeks. Eight days at the Agamemnon campsite had revived her. For the first three days she had stayed inside the habitat dome, and then she took to leaving the habitat dome for just one hour each day.

  First she would walk over to the greenhouse module. She was amazed that it had survived, untended, for years on the Martian surface, and even had plants inside, some sort of tough yucca and several evergreen shrubs. She rubbed her hand over them, feeling the prickly points. You are like me, she told them silently. We are survivors.

  Then she would go to walk along the deserted beach just before sunset.

  The water of the ancient ocean was long gone; the sa
nds of the beach had long ago cemented into a rocklike caliche. She could read the ebb and flow of the waves in the ripples frozen into the sandstone. She would find a shallow basin and brush away the covering dust, and find below the white layer of evaporite, salt crystals.

  One time, walking a little inland, she found yet another fossil, embedded in the wall of a limestone cliff. It was exactly the same shape as the others, but this one was immense, as large as a whale, ten meters from end to end. Estrela wondered that these were the only type of fossils that they saw. Had there been only one form of life on Mars? Or perhaps only one type had fossilized.

  And the sun would set, and she would return into the habitat.

  Inside the dome was paradise, with plentiful liquids and warmth, with enough water to heat an entire liter of bathwater at once and let it dribble, sensuously, over her body. It felt like a decadent luxury.

  Her throat no longer hurt so much. She could even speak, in a voice louder than a whisper.

  She carefully plaited her now-blond hair, and barely wore clothing. Ryan was the one who would make the decision now, she knew. Two women, and he would be able to take only one home.

  But Ryan barely looked at her, although she tried in a dozen subtle ways to contrive to be there, nearly naked, when he was in the habitat, and he would hardly have been able to miss her. But he never made a move.

  Ryan was good-looking. Oh, not as good as João—Santa Luzia, who could possibly be as gorgeous as her beautiful João had been?—but he was fine. But he seemed to pay no attention to her.

  Two women, and only one would get to go with him back home. Well, the odds were much better than they had been. She knew men, and knew that if there had been two men, somehow the men would have contrived a way to show that it was logical for the two men to go home to Earth and the women stay behind to die. It was just the way of the world.

  She wondered if Tana knew how much she hated her.

  9

  THE CANADIAN ASTRONAUT

  At SPAR Aerospace, Ryan Martin worked on designing tether deployment systems for space; much later, his expertise on the use of tether systems played a major part in his role in the failed Mirusha rescue attempt. He spent a year in France, to earn a degree in space studies at the International Space University in Strasbourg, and the day he came back to Canada he put in his application to join the small Canadian astronaut corps.

  His application went in just in time to apply to join the first Canadian cadre selected specifically for duty to the space station. His low amount of piloting time counted against him. He had taken flying lessons and spent as much time as he could afford practicing, but he certainly had far fewer hours in the air than the RCAF pilots that applied for the same few slots. But no one had a more thorough grasp of every aspect of astronautics and microgravity science than he, and in the end that counted more than his relative lack of flight hours. He wasn’t being trained to be a pilot anyway; the Americans would never select a Canadian to fly their shuttle. For the tasks Canada wanted astronauts for, they needed expertise in all areas, and no one scored higher than Ryan.

  He graduated at the top of his astronaut training class.

  His appointment to the astronaut corps elicited mixed feelings for him; during those years the fate of the space station was uncertain, and whether the space station had any role at all in the future exploration of space, or if instead it was an expensive orbiting dinosaur, was quite unclear. He wondered if the real future might instead lie in commercial space, where new, small launch vehicles were beginning to make enormous profits from launching tiny, cheap satellites.

  But he wanted to do more than just send up other people’s satellites.

  Ryan Martin wanted to go to Mars.

  Mars was his obsession. He thought about Mars, made calculations, read every book, science or science fiction, that had ever been written about Mars, published papers suggesting possible solutions to the finicky engineering details of a Mars mission. After a while he started to be invited to give lectures about Mars missions, and he found that he was good at it. He would rent an airplane and fly to some distant city and talk. Schoolchildren, Masonic temples, library groups—he loved the moment when a group of strangers suddenly warmed up, and his contagious enthusiasm spread.

  He didn’t chase women—to tell the truth, he had never learned how to approach a woman—it seemed to be an arcane trick that other men learned in some class he had failed to attend—and so he treated all the women he met exactly the same way he treated the men: as coworkers or as friends. But occasionally women would ask him out, and he wasn’t against going out to a restaurant, or to a concert, or for a walk on the beaches of Lake Ontario. And afterward, if sometimes a female friend asked him back to her apartment, or his, well, he had taken no vow of chastity.

  He had only two rules to his relationships, rules that he never broke. Never promise anything.

  And never fall in love.

  10

  RIDING THE SLINGSHOT

  Butterfly had been designed for short hops and aerial reconnaissance, not for a two-thousand-mile flight, and it had not been designed to carry three people. Over the months that they spent at Acidalia, Ryan ripped out every part that was not critical to flight: all the redundant control systems, the scientific instrumentation. He cut off the landing gear; when she landed, the Butterfly would land on snow. And she would never take off again.

  They would have no margin, but at last he had an airplane that would make it to the pole.

  For the take-off, Ryan laid down two strands of the superfiber cable for three kilometers along the desert sand. At the far end he staked it down to bolts drilled into bedrock, and then went back and used the motorized winch to stretch it. The elastic energy that can be stored in superfiber is enormous: If it were to suddenly break, the release would snap the cable back at almost hypersonic velocity, setting free enough energy to vaporize much of the cable, as well as anybody who stood nearby.

  Once he had it stretched, he held it stretched with a second anchor bolt. It formed a two-mile-long rubber band. Ryan would use the world’s largest slingshot to launch the airplane.

  The airplane had only two seats, so Estrela and Tana both were crammed into the rear copilot’s seat of the airplane, Estrela perched on Tana’s lap. In their bulky Mars suits, they fit into the space with barely millimeters to spare.

  Ryan closed and sealed the cockpit around them and took the pilot’s seat.

  “Ready?” Ryan asked.

  “As ready as we’re going to be,” Tana’s muffled voice said.

  “Get on with it!” Estrela said.

  “Armed,” Ryan said. He pulled out an arming switch on the remote control, and said, “Launch!”

  The explosives fired in silence, but Ryan could see the flash behind him, severing the strap that held the stretched superfiber down. Instantly he was pressed back into his seat as the superfiber slingshot, attached to the airplane at the motor mount, grabbed the airplane and shot it forward. Behind him he heard Tana say “Yikes!” and Estrela let out a sudden grunt as the sudden weight pressed into her.

  The ground rushed past them with terrifying speed. Ryan concentrated his attention on keeping the wings level; with even a slight brush of a wingtip against the sand the fragile airplane would disintegrate around them. He couldn’t spare any attention for the airspeed indicator, but he could feel the wings beginning to pull against the air. He held forward pressure on the stick to keep the nose down; they needed to reach flying airspeed as quickly as they could. He shot a glance down at the airspeed; not yet, not yet. Now.

  He eased back on the stick—not too much, or the wings would be ripped off—and the ground dropped away under them. Now Butterfly was lofted like a kite being towed behind a running boy. The pressure from the slingshot eased off; they were running out of stretch. It had been only a few seconds. He concentrated on keeping his airspeed up while milking the last little bit of altitude out of the quickly relaxing slingshot.
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br />   The slingshot slackened and fell away. For a moment Butterfly was soaring. He commanded the valves on the liquid oxygen tanks open, armed the ignition switch, and watched for the green light. After a terrifying pause, it flickered on.

  They were ready.

  Ryan hit the ignition button, and with a shudder, the ram-rocket chuffed to life.

  For the first time in weeks, Ryan felt a surge of hope. Maybe they would make it after all. They were flying. Flying!

  11

  MOMENTUM MANAGEMENT

  Other astronauts who flew up on the shuttle with him felt sick. Ryan felt exhilarated. Every part of it was exciting, the training, the launch, and now the free-fall. This was what he’d always wanted. He tried a slow flip, then a fast one. “This is great,” he said.

  But he was here to work, not to play. He had the map of the space station memorized. The others went quickly to find the station physician, or at least to find vomit bags. “They’ll get over it in a day or so,” the station physician said. “How about you? You okay? Need a patch?”

  “No. I’m fine.”

  The doctor nodded. Ryan was fascinated to see how his body moved infinitesimally in the opposite direction as he did. “Some people aren’t affected. Guess you’re lucky.”

  He went to work.

  After a while, when he was alone in a module, one of the female astronauts floated over. She casually snagged a handrail next to him, and looked at him, floating upside down.

  He looked up.

  “Are you gay?” she said.

  “Huh? No.” He tried to remember her name. He was supposed to know the names of all the people on the station, but he’d never been good with names. Britta, he recalled, Britta Silverthorne. That was it.

  “Nothing wrong if you are,” she said.