Scientists with tweezers picked through the twisted wreckage of a space capsule that crash-landed on Earth, hoping that microscopic clues to the evolution of the solar system weren't completely lost in Utah's salt flats.

NASA engineers were stunned Wednesday when neither parachute deployed aboard the Genesis capsule (search) and the craft plummeted to the ground at 193 mph, breaking open like a clamshell and exposing its collection of solar atoms to contamination.

"There was a big pit in my stomach," said physicist Roger Wiens of Los Alamos National Laboratory (search). "This just wasn't supposed to happen. We're going to have a lot of work picking up the pieces."

The capsule held billions of charged atoms — a total haul no bigger than a few grains of salt — that were harvested from solar wind on five collecting disks during the 884-day, $260-million mission.

Roy Haggard, who took part in the initial reconnaissance of the capsule, said the capsule's shell had been breached about three inches and the science canister inside appeared to have a small break.

The inner canister was flown to the Army's air field at the proving ground and put in a clean room, a work area in which the air quality, temperature and humidity are highly regulated to prevent contamination.

The reconstruction was expected to take several days, and scientists were hopeful they could salvage the embedded atoms among the twisted platters of exotic metals and silicone.

"This is something that's not a total disaster," said Carlton Allen, astromaterials curator for the Houston-based Johnson Space Center (search). "We didn't lose all the science in the crash."

NASA planned to appoint a "mishap review board" to determine a cause for the failure. Flight engineers say a set of tiny explosives didn't trigger the capsule's parachutes, although the fact that all explosives failed pointed to another cause.

The spacecraft was designed and built by Lockheed Martin Space Systems (search) near Denver. Robert Corwin, an engineer for the company, said a battery that overheated shortly after the 2001 launch could be a culprit.

The mishap also raised questions about the durability of another NASA sample-return capsule called Stardust, due to land here in 2006. But that capsule was built to be more rugged and will land on its own with a parachute.

Scientists got their first glimpse of the damage when the Genesis capsule was wheeled into a garage bay late Wednesday. The capsule's inner canister was all but unrecognizable, although scientists thought they saw some unbroken parts holding the atoms.

The space capsule had been outside the earth's magnetic shield for three years, collecting solar wind particles that could explain how the sun formed an estimated 4.5 billion years ago and what keeps it fueled.

The atoms were captured on 5-foot disks, each with hexagons of gold, sapphire, silicone and diamond. Each collector array was assigned to catch various types of solar wind.

The five disks were of different thicknesses, which could make it easier for scientists put the pieces back together like a puzzle, Wiens said. The disks were so tightly packed within the canister that it was hard to tell how badly they were damaged.

Helicopters flown by Hollywood stunt pilots were supposed to grab Genesis almost a mile above the Utah desert and lower it gently to the ground by snatching its main parachute with a hook. But before the capture team learned of the parachute failure, the speeding capsule had plummeted into the Utah desert.

Solar wind is a stream of highly charged particles that are emitted by the sun. The Genesis mission marked the first time NASA has collected any objects from farther than the moon for retrieval to Earth.

Scientists hoped the charged atoms gathered in the capsule would shed important light on the solar system, said Don Burnett, Genesis' principal investigator and a nuclear geochemist at California Institute of Technology.

"We have for years wanted to know the composition of the sun," Burnett said before the crash. He said scientists had expected to analyze the material "one atom at a time."