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NASA's Spirit Rover Lands on Mars; 'We're Back,' Says Space Agency Chief

Posted on: Sunday, 4 January 2004, 06:00 CST

Jan. 4--PASADENA, Calif.--A NASA Mars lander touched down on the Red Planet late last night, marking a crucial step in a renewed, ambitious search for signs of life there.

As dozens of engineers and scientists hugged and jumped up and down at mission control at the Jet Propulsion Laboratory here moments after the 11:35 p.m. touchdown, NASA officials said pictures from the Martian surface could be transmitted to Earth within hours. The signal from more than 100 million miles away means that the craft survived a perilous 6-minute descent through the Martian atmosphere and dozens of bounces on the surface to roll to a stop in an ancient crater.

"This is a big night for NASA. We're back," said Sean O'Keefe, the NASA administrator. The lander is cradling a 384-pound rover named Spirit designed to search for signs of past water that could have supported life. "I'm very proud of this team -- and we're on Mars."

If the lander successfully unfolds and Spirit hits dirt in a little more than a week, it could mark NASA's first successful return to the Martian surface since 1997. Such a success holds deep significance for an agency that has come under severe criticism since the Columbia shuttle disintegrated during re-entry last Feb. 1, killing all seven astronauts aboard. Two of NASA's last three Mars missions have failed, and the agency has embarked on a major overhaul of its management strategy.

The Spirit rover is designed to help kick off the most exhaustive exploration of another world since the Moon landings of the Apollo era. It is the second of a planned series of missions that could culminate in a craft that brings back samples of Mars rock to Earth.

Although NASA officials were fastidious in laying out all the worst-case scenarios the mission could encounter, it occurred with hardly a hitch, from the shedding of the lander's heat shield to the inflation of air bags. Scientists were nervous the rover would land with its antennas in the wrong position to communicate with Earth, but the signal was strong within ten minutes after touching down. The lander also came to rest on its base, which will make it easier to unfold its petals.

"I really like doing it when it looks like this," said Richard Cook, deputy project manager for the Jet Propulsion Laboratory. The craft's intended landing site is an ellipse of relatively flat land 39 miles long by 2 miles wide in the Gusev Crater but scientists won't know its exact location until today.

To improve its chances of success, NASA has sent twin rovers on this mission. Spirit is set to be joined by Opportunity on Jan. 25, which will touch down on the other side of the planet in Meridiani Planum, a smooth plain holding a mineral that offers a tantalizing suggestion of a wet past. Both craft were launched last summer, during a period of close alignment between Earth and Mars that occurs every 26 months.

The goal of the mission is to examine the cold and dry planet for signs that it once held water, searching for minerals that point to a history of rivers, precipitation, or other environmental features conducive to life.

Based on increasingly detailed information from probes orbiting Mars, researchers know that Mars has water ice at its poles and suspect that gullies and channels on the arid surface were once carved by water, but don't know when the water existed -- or if it lasted long enough to support life. The rovers are equipped with a robotic arm that uses a grinder to scrape away rocks' weathered surfaces, and can peer inside with cameras and spectrometers looking for visual and chemical signatures of past water.

With an approximate ten-minute communication lag from their controllers at the Jet Propulsion Laboratory, neither rover will be moving quickly. Their maximum speed is about 300 feet per day.

In fact, the amount of physical work each will complete in its 90-day expected lifespan is about the equivalent of what a human geologist can do in 90 minutes.

The Spirit "doesn't move fast," said John Grotzinger, a Massachusetts Institute of Technology geologist.

Grotzinger heads a team that will help decide what geological feature Spirit will visit and what it will do, based on what the rover's cameras and spectrometers are analyzing. The decisions are important: The rover only has at most about 3 months before Mars's fine dust covers its solar panels, making it inoperable.

Spirit and Opportunity are much more advanced robots than the last successful Mars lander, the two-foot-long 1997 Sojourner rover, and are large enough to roll over their smaller cousin. Each rover is equipped with more sophisticated cameras, tools, and spectrometers than Sojourner.

They have also benefited from increased scrutiny by scientists and engineers, stepped up after the $165 million Mars Polar Lander was lost in 1999, probably because of a software error. That year, an orbiter was also lost.

Those probes were the product of NASA's "faster, better, cheaper" effort to explore space by sending up large numbers of relatively inexpensive probes. That approach ultimately proved wasteful, critics said, because it did not include enough scrutiny to catch errors.

For this Mars mission, each piece of the $820 million project was peer-reviewed and exhaustively analyzed by teams of specialists. More rigorous software testing also helped scientists understand in more detail where systems could fail, and create protections against even the most unlikely scenario.

And in case the lander still failed, NASA engineers programmed key tones to be broadcast back to them during the critical stage of the descent, so they would have some chance of tracking what went wrong.

"This went to perfection," said Rob Manning, who oversaw the entry, landing, and descent of the lander.

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(c) 2004, The Boston Globe. Distributed by Knight Ridder/Tribune Business News.

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