On January 3, 2004, a strange sight unfolded on the planet Mars. Above a vast, dry lake bed south of the martian equator, a conical vehicle parachuted toward the surface. Then, just before touch down, it was enveloped by a gigantic protective airbag allowing the craft to bounce safely to a stop. Inside was Spirit, the most sophisticated rover ever launched from Earth. "MARS Dead or Alive," which originally aired just hours after Spirit landed on the red planet, covers this mission in depth.
The program's behind-the-scenes look at the construction of Spirit and its twin, Opportunity, includes a special up-to-the-minute segment with the latest news from Mars as of January 3, 2004—to learn if Spirit is ready to undertake the most comprehensive search for evidence of liquid water ever attempted on Mars.
NOVA spent months documenting the tension-filled process of building, testing, final checkout, and launch of a pair of spacecraft that are designed not only to be remote-controlled field geologists but to perform in a demanding environment millions of miles from Earth. As the program shows, unexpected problems with designs for the parachute and airbags almost scuttled the mission, and a potentially catastrophic electronic problem on Spirit didn't turn up until the vehicle was completely inaccessible and awaiting launch.
Riding on the mission are not just the hopes of scientists seeking to answer baffling questions about the history of Mars, but the future of NASA's Mars exploration program itself. Twice in 1999 NASA probes arriving at Mars were lost without a trace. One of the few recent bright spots for Mars research was the surprising success of the experimental lander-rover Pathfinder in 1997, which was designed to test the airbag-landing technique.
Pathfinder was spawned by a freewheeling group of young scientists and engineers who are now back with the far more ambitious Spirit and Opportunity vehicles, which make up what is officially called the Mars Exploration Rover (MER) project. The MER science team is headed by planetary scientist Stephen Squyres of Cornell University, who conceived the project with the goal of probing the most burning questions in Mars science: Was there ever liquid water on the Red Planet? Were conditions ever suitable for life?
Spirit and Opportunity are mobile laboratories outfitted with visible-light and infrared cameras to scan the landscape and locate promising rocks for investigation; a power tool to grind off the weathered surface; a microscope to examine the interior; and two other instruments to sniff out the rock's chemistry. (For a closer look at a MER, see Anatomy of a Rover.) In this way, the MER team held out hope of finding evidence of the liquid water that many scientists theorize was once abundant on Mars's surface but has since vanished.
The landing sites were chosen for their strong signs of a wet past. Spirit is now on site in Gusev Crater, a possible former lake, while Opportunity has been exploring Meridiani Planum, where minerals have been detected that normally form in the presence of water. And where there's water, there may have been life. The ultimate goal of Spirit and Opportunity is to shed light on this intriguing possibility and perhaps pave the way for the most versatile explorers of all—humans.
Original PBS Broadcast Date: January 4, 2004. Season 31 - Episode 09
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