Comet Wild samples near home

Wednesday, January 11, 2006

Artist's Impression

Stardust, a NASA space capsule carrying precious comet samples from deep space, is scheduled to return to earth January 15, 2006.

Scientists hope to discover new meaning to the beginning of our solar system.

Stardust's 2.9 billion mile round-trip mission took it halfway to Jupiter to catch particles from Comet Wild 2 two years ago. Its journey will have lasted a total of just over seven years when it lands in the Utah desert.

On Sunday, the ship will remain in space while a 100-pound (45 kg) capsule loaded with comet dust returns to earth and lands at the U.S. Air Force Utah Test and Training Range at 3:12 a.m. local time (5:12 a.m. EST or 1012 GMT). If the skies are all clear on January 15, then people from Northern California, Oregon and Nevada could get quite a show as the capsule enters Earth's atmosphere. The show will be quick, but should prove impressive.

Stardust EDL Groundtrack

Comets are thought to be remnants from the process of planet formation, and scientists said the dust collected by Stardust will give them their first opportunity to study pristine samples of materials formed billions of years ago. The particles from the comet were captured using a tennis-racket-sized space probe containing ice-cube sized compartments lined with aerogel, a porous substance that is 99.9 percent air. It is the first time since 1972 that any solid extraterrestrial material has been collected and brought back to Earth, and the first time ever for comet particles.

During its descent over the desert, the capsule is scheduled to deploy two parachutes, though NASA officials said they have prepared for the possibility of a hard landing. A NASA probe called Genesis crashed to Earth in 2004 when its parachute failed to open. That craft had been on a three-year mission to collect solar wind ions, which were recovered by scientists even though the spacecraft was destroyed.

Stardust's project manager, Tom Duxbury, said that "after the Genesis incident and the Columbia shuttle disaster, the mission's team spent six months testing and reviewing the spacecraft's design to make sure there were no errors". Once the craft is recovered, it will be whisked away to the Johnson Space Center in Houston. Only after it is in a secure lab, free of potential contamination, will the probe be pried open to reveal its payload.

"We are at the end of a fantastic voyage," Don Brownlee, the lead scientist for the mission known as Stardust, recently told reporters at a media briefing. "We will learn a phenomenal amount… from the most primitive materials in our solar system. It is a real thrilling time." Now, near the end of its long voyage home, the probe is set to plunge back to Earth in the predawn hours on Sunday.