Smooth landing for NASA probe carrying comet

By Nichola Groom

LOS ANGELES (Reuters) – A space capsule loaded with comet
dust completed a 2.9 billion mile (4.7 billion kilometer)
journey on Sunday, 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
(45 kg) capsule landed at the U.S. Air Force Utah Test and
Training range two minutes ahead of schedule at 3:10 a.m. (5:10
a.m. EST/1010 GMT).

“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 solid
material from beyond the moon 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.

RACING BACK TO EARTH

The canister entered the Earth’s atmosphere at a speed of
28,860 miles per hour (46,440 km per hour), the fastest of any
man-made object on record. It took just 13 minutes for the
capsule to travel through the atmosphere on its way to the
remote military base.

Less than an hour after the landing, three helicopters
retrieved the capsule from the windy and dark desert floor,
helped by infrared and radar tracking devices.

Recovery of the muddied but intact capsule took slightly
longer than expected, officials said, because heavy winds blew
it north of its exact target.

The vessel was taken to a “clean room” at the base where
the canister containing the particles will be removed from the
capsule before being shipped to Johnson Space Center in Houston
on Tuesday for scientists to study.

“Much of the science of this mission hasn’t been done yet,”
said Brownlee.

Stardust’s mission, which began in 1999, took it around the
sun three times and halfway to Jupiter to catch particles from
comet Wild 2 in January of 2004. The dust was captured by a
tennis-racket-shaped space probe containing ice-cube-sized
compartments lined with aerogel, a porous substance that is
99.9 percent air.

The particles, most of which are expected to be a tenth as
wide as a piece of human hair, lodged in the aerogel before
being shuttered inside the capsule.

Stardust’s mother ship, which severed the umbilical cables
between it and the capsule late on Saturday, returned to orbit
around the sun and may be used in future missions to study
planets, asteroids or comets.