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| Prologue: Six Wheels on Soil | |
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| Before dawn on July 4, 1997, I woke with my mind over a hundred million miles away. My waking thoughts were all of Pathfinder, the United States' first attempt to land on Mars in twenty years, as it hurtled through the silence of space just hours away from its encounter with the red planet. The 100-foot-high Delta 2 rocket that had boosted the spacecraft from Cape Canaveral, Florida, seven months earlier was finally about to deliver something very precious to me, and I can't say I wasn't anxious. | |
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| Cabled down firmly inside this streaking bullet was Sojourner Truth, the world's first robotic planetary rover. I headed the team that had designed and built this revolutionary six-wheeled scientific laboratory, a 25-pound robot about the size of a microwave oven that could do what humans could only dream of: explore the surface of Mars. I'd spent nearly ten years of my life preparing the two of us for this moment. | |
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| I could picture her cradled in the heart of the lander like the tiniest Russian nesting doll. She crouched with her belly to the floor inside a lander that was packed in a cushion of deflated airbags. Once off the lander, she would motor over the surface of Mars taking pictures and poking at the rocks like a tourist. She was a sturdy little gal. We'd whirled her in a centrifuge at a force 66 times that of gravity, twice as much pressure as we expected her to endure in flight, and she'd come out perfectly. If Pathfinder landed the way it was supposed to, I was sure she'd be fine. | |
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| I knew the Pathfinder's innovative landing mechanism almost as intimately as I knew the rover. Retro-rockets would slow the craft to a stop just before it smacked into the Martian surface. Moments before it hit the ground, huge airbags would pop. If everything worked--if all the radios communicated, the signals and sequences were sent and received, every one of the explosive bolts fired promptly and the airbags popped firm exactly on cue--it would plump up and bounce across the ground like a giant superball until it came to a rest. It was an inspired and thoroughly tested design, but one that had never before been used to land on a planet. | |
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| Surely this scheme had a better chance of keeping the Sojourner intact than anything previously devised. The teams that designed the lander and the rover had spent hours concocting every imaginable disaster scenario and building in ways to overcome those. We were combating long odds, if history was to be believed. Throughout thirty-seven years of exploration, Earthlings hadn't been terribly successful landing on Mars. | |
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| Two Russian Phobos spacecraft were lost on their way to Mars in 1988. While the United States' two Viking missions landed safely in 1976, our Mars Observer failed to reach orbit in 1993. The Russians' Mars 6 and 7 got to Mars in 1971, but couldn't deliver their landing craft. Mars 6 crashed into the surface and Mars 7 missed the planet completely. As recently as November 1996, the Russian Mars 96 mission plunged ignominiously into the Pacific, never getting anywhere near its target. What if something like that happened to my rover? The data assured me that Pathfinder was approaching Mars just fine, but almost anything could happen during the punishing six-minute descent to the surface. Crash and burn was a definite possibility, I knew. Crash and burn. | |
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| Of course she wasn't really my rover. I had headed the team of thirty talented engineers and technicians that had spent four years designing and building the rover. A separate 300-member team, led by project manager Tony Spear, had spent the same amount of time building the Pathfinder lander. All of us could rightfully think of this mission as our own. No matter what any of us were doing at that moment on Earth, we could picture Pathfinder and Sojourner about to begin their descent and we knew our hopes could be dashed against the forbidding landscape. | |
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| I hadn't slept at all well that night. I've always been a fitful sleeper anyway, tossing and turning in the wee hours anticipating the day to come as my mind races with ideas and plans. In the early morning hours before Pathfinder entered the Martian atmosphere, dreams yanked me just to the edge of consciousness time and again. These weren't the idyllic dreams of me flying solo over the surface of Mars, such as I'd had since I was a small child in Oklahoma. The dream that eventually convinced me I might as well get out of bed was more of a farce. | |
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| In this dream, I saw the Pathfinder team standing around a field when suddenly our spacecraft fell from the sky before us. It had landed on Earth! We watched it bound to a stop but the airbags didn't deflate. My teammates seemed merely befuddled by this disaster. I hopped around eagerly, wondering how they could be so detached. I wanted to open it up, see how Sojourner had survived the descent. Everyone else said we had to let the lander open by itself. I guess I should see this dream as an encouraging omen, I decided as I got out of bed. If Sojourner could endure the descent through the Earth's dense atmosphere--even in my dreams--then the wispy carbon dioxide atmosphere of Mars would feel as gentle as a tropical breeze. | |
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| I found no comfort in my morning ritual, no solace from my habitual cup of tea. I barely tasted my orange as I methodically swallowed it. Sitting at home was just making me restless. I felt like a child the night before Christmas anticipating a desperately-wished-for present. I put on my favorite suit--Mars red--and decided it was best not to wake my daughter, Laura, who was home from college for the summer. She planned to catch up with me around 10 a.m.,the moment the Pathfinder was scheduled to enter the Martian atmosphere. She could use the sleep for the eventful day ahead, I thought. I drove the six miles from my house in La Canada to the Jet Propulsion Laboratory (JPL), in California, arriving at 6:30 a.m., an hour before I was supposed to report for work. | |
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| Though I'd driven the two blocks of Oak Grove Drive nearly every day for the thirty years I'd worked at JPL, I'd never seen it as packed with journalists as it was that day. Local, national, and international television trucks lined the street. Von Karman Auditorium, near the entrance to the JPL campus, bustled with print and radio reporters already hard at work on this story. Photographers snapped pictures of the full-scale models of the Pathfinder we'd displayed on the JPL mall and in the auditorium. Video crews jockeyed for position around the models and on the risers at the back of the auditorium. Competition for a good spot was so heated that JPL had taped off separate areas for each crew to prevent squabbles. I knew the Fourth of July was a slow news day, but I'd never expected the interest to be as high as this. Something about Pathfinder and Sojourner had really captured the public's imagination. | |
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| The generation that had grown up watching Star Trek and Star Wars really hadn't seen a planetary landing in its lifetime. For this generation, the Pathfinder mission was akin to Neil Armstrong's moon landing on July 20, 1969. We knew we already had a built-in international audience of the millions of people who had tracked the mission's progress on the Internet Web site we'd constructed for Pathfinder before it took off on December 4, 1996. Popular culture fostered an interest in space, but the real world rarely delivered the goods. Today--on Independence Day no less--the real world was delivering. | |