NASA rover signals earth after Mars touchdown

The NASA rover has landed safely on Mars, beginning a mission to roam the Red Planet in search of evidence that it was once suitable for life.

Scientists at NASA's Jet Propulsion Laboratory let out whoops of joy and embraced one overnight as signals from the Spirit rover indicated it had survived the landing.

"This is a big night for NASA — we are back!" NASA administrator Sean O'Keefe crowed at a celebratory news conference early Sunday, relishing a success after a difficult year that included the agency's 1 February Columbia space shuttle disaster that killed seven astronauts.

"I'm very, very proud of this team and we're on Mars. It's an absolutely incredible accomplishment," O'Keefe said. He then toasted the mission's members with champagne he said he had been saving for more than 20 years.

Previously, about two of every three attempts to land spacecraft on Mars have failed. The latest apparent failure was the British-built Beagle 2 lander, which has not been heard from since it was to have set down on Mars on Christmas Day.

Spirit was expected to emerge from inside the flowerlike lander within its first 90 minutes on Mars, after it retracts the air bags that cushioned its landing. Spirit also should deploy its solar arrays during that time.

The spacecraft eventually landed upright last night, which will make unfolding it easier, said Chris Jones, director of planetary flight programs at NASA's Jet Propulsion Laboratory.

"That is how we hoped it would land," Jones said.

Spirit is one of two-identical six-wheeled robots expected to roam the planet for 90 days, analyzing Martian rocks and soil for clues that could reveal whether the planet was ever a warmer, wetter place capable of sustaining life.

Mission officials said the rover could start snapping pictures of Mars late Saturday night, but won't trundle off on its own for another nine days.

"We could get part of a panorama this evening. There's nothing better," said JPL's Matthew Golombek, who helped pick the rover's landing site on Mars inside Gusev Crater, an Israel-sized indentation just south of the Martian equator.

The rover relied on a heat shield, parachute and rockets to slow its descent to Mars. Eight seconds before landing, a giant set of air bags inflated to cushion its bouncy landing.

"This is essentially perfect navigation. We couldn't have possibly hoped to do better than this," navigation team chief Louis D'Amario said.

Previously, about two of every three attempts to land spacecraft on Mars have failed. The latest apparent failure was the British Beagle 2 lander, which has not been heard from since it was to have set down on Mars on Christmas.

"It's an incredibly difficult place to land. Some have called it the 'death planet' for good reason," said Ed Weiler, NASA's associate administrator for space science.

NASA's last attempt at landing on Mars, in 1999, failed when a software glitch sent the Polar Lander crashing to the ground. Since then, the space agency has increased oversight of its missions.

The $820 million NASA project also includes a twin rover, Opportunity, which is set to arrive on Mars on Jan. 24.

Today, Mars is a dry and cold world. But ancient river channels and other water-carved features spied from orbit suggest that Mars may have had a more hospitable past.

"We see these intriguing hints Mars may have been a different place long ago," said Steve Squyres, the mission's main scientist.

The rovers were built to look for evidence that liquid water — a necessary ingredient for life — once persisted on the surface of the planet. A direct search for life on Mars is at least a decade away, NASA scientists said.

Together, the robots were launched in the most intensive scientific assault on another planetary body since the Apollo missions to the moon, said Orlando Figueroa, director of NASA's Mars exploration program.

NASA launched the 384-pound (173-kilogram) Spirit and its twin in hopes they would become the fourth and fifth U.S. spacecraft to survive landing on Mars. Twenty other spacecraft from various nations have failed.

Scientists are taking advantage of the closest approach Mars has made to Earth in 60,000 years. NASA intends to send spacecraft to Mars at regular 26-month intervals, or each time the Earth laps the Red Planet as they both circle the sun.

The highly anticipated Spirit landing follows another important American space mission. On Friday, a NASA spacecraft flew through the bright halo of a distant comet to scoop up nearly a thimbleful of dust that could shed light on how the solar system was formed.

On the Net: marsrovers.jpl.nasa.gov/home/index.html