WASHINGTON- After three years and a 2 million mile journey toward the sun, NASA’s Genesis… WASHINGTON- After three years and a 2 million mile journey toward the sun, NASA’s Genesis space capsule smashed into the Utah desert Wednesday when a pyrotechnic charge failed to deploy its parachute.

Somber NASA scientists say they don’t know whether the precious samples that Genesis collected on its $264 million mission were destroyed.

It broke a string of successes for the robotic exploration program at the National Aeronautics and Space Administration, which had planned to use a Hollywood stunt pilot in a helicopter to snag the probe by its parachute as it floated gently toward Dugway Proving Ground in Utah. Scientists said they hoped Genesis’ cargo- particles of solar wind collected on special tiles- survived the crash.

“There is still hope for a science result for this mission,” said Don Sweetnam, the project manager for Genesis at NASA’s Jet Propulsion Laboratory.

When mission managers spotted the capsule without its parachute, it was clear something was wrong. Instead of watching the daring mid-air maneuver to capture it, they saw Genesis tumbling wildly, end over end, and spinning out of control.

“Our hearts started racing a little faster, and before you knew it, it was on the ground,” Sweetnam said.

After hitting the ground at nearly 200 mph, the 420-pound capsule partly sank into the desert floor with a splash of sand debris around it. The capsule itself was severely damaged, but appeared to be intact.

NASA will name a team to investigate what went wrong with the mission, which started with a launch from Kennedy Space Center in August 2001.

Andrew Dantzler, the solar system division director at NASA headquarters in Washington, said the accident was not a worst-case scenario because the container holding the samples was not destroyed.

But the long faces at a post-mortem news conference said it all: the disappointment and dismay were evident.

Genesis was the first attempt to bring back samples from space since the Apollo missions fetched moon rocks back to Earth. If scientists can salvage any of the samples, it will be the first time material from beyond the moon has been brought back to this planet.

During its journey, Genesis traveled to a point just under 1 million miles from Earth where the gravities of the planet and the sun are balanced. The spacecraft orbited the point five times- a “halo” orbit, meaning the spacecraft orbited an empty spot in space, not a physical object.

Genesis began collecting particles of solar wind in December 2001, and continued until April, when it began a series of looping maneuvers to send it back toward Earth.

Scientists are interested in the solar wind samples to help them understand the composition of the solar nebula- out of which, some scientific theories hold, the current variety of planets, moons and other bodies formed.

Scientists hope to examine the ratio of isotopes of different matter contained in the sample material, to help them better understand the solar system.

The samples were gathered by five collector arrays, each one about one yard in size and studded with 55 hexagonal tiles, each about 4 inches across. The tiles were of varying materials- from silicon to sapphire- each designed to pinpoint different elements when they are analyzed.

During the journey, the arrays were tucked inside a super-clean canister to prevent the sample material from being contaminated. While it was in space, instruments on board the spacecraft also measured changes in the solar wind.

The mid-air catch was designed to prevent Genesis from hitting the ground, even with a parachute, because the tiles inside are that fragile. So program managers knew when it splattered on the ground that they would be lucky to recover anything from the mission.

While scientists are scrambling to salvage some research-worthy material, others will be trying to figure out exactly what went wrong.

The parachute is supposed to deploy with a small mortar explosion. But that never happened- in fact, the unexploded ordnance kept investigators at bay initially out of fear the charge could suddenly blow.

Sweetnam said the spacecraft underwent a complete risk analysis fairly recently. But in many ways, he said, there was not much that could have been done once the spacecraft blasted off.

“Keep in mind that when we buttoned the thing up at Kennedy Space Center and launched it in 2001, the fate was sealed,” he said. “There was really nothing we could do at this stage to change things.”

The material inside the capsule poses no risk to people, officials said. Wednesday’s disappointment ends a string of spectacular successes for NASA’s robotic space program. The streak began in January, when the Stardust probe survived a plunge through a comet 242 million miles from Earth. The probe is supposed to return in January 2006 with a similar parachute mechanism as the one used in Genesis.

Also in January, the twin Mars rovers Spirit and Opportunity reached the Red Planet safely, and have sent back reams of photos and data. On July 1, the Cassini-Huygens probe reached Saturn, sending back breathtaking photos of that planet’s rings.

Wednesday’s failure raises questions about potential future sample-return missions from places such as Mars. While the material collected by Genesis was considered harmless, samples from other planets would need to be more carefully protected from contamination- and from contaminating our home planet.

The engineers and scientists who spend years- and sometimes decades- working on these projects spent a lot of time sounding notes of caution. Anything can go wrong, they say, anytime.

With Genesis, at the end of a long and groundbreaking trip, those caveats came true.

Sweetnam said he had been running every checklist, every tweak, every move the team has made through his mind. Nothing stood out, he said- but sometimes, a fluke is all it takes.

“It’s a very difficult moment right now,” he said.

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