Comet dust probe 'may hold key to solar system'

Last updated at 17:15 15 January 2006

A space capsule loaded with comet dust has completed a 2.9 billion mile journey, landing safely in the Utah desert and ending a seven-year wait for clues to the solar system's origins.

The Stardust mission ended early Sunday when the 100-pound capsule landed at the US Air Force Utah Test and Training range two minutes ahead of schedule at 3.10am (10.10am UK time).

"We visited a comet, grabbed a piece of it, and landed here this morning," said Don Brownlee, an astronomy professor with the University of Washington who is principal investigator for the Stardust mission. "It was a real thrill."

The mission marks the first time since 1972 that any extraterrestrial solid material has been collected and brought back to Earth, and the first time ever for comet particles.

Comets are thought to be leftovers from the process of planet formation, and scientists hope the dust collected by Stardust will give them clues about the origins of the solar system 4.5 billion years ago.

Television images showed scientists and engineers in the control room at NASA's Jet Propulsion Laboratory in Pasadena, California, cheering and applauding both at landing and earlier when the capsule's two parachutes deployed as it roared across the western United States toward its target.

"This thing went like clockwork," Stardust Project Manager Tom Duxbury said at a news conference following the landing. "To see that thing in one piece on the floor of the desert is very moving."

In 2004, a capsule called Genesis carrying solar ions crashed to Earth when its parachute failed to deploy, raising concerns about Stardust's return. The Stardust team spent six months reviewing its spacecraft's design to make sure there were no errors, and NASA officials said they were prepared for a hard landing.