DUGWAY PROVING GROUND, UTAH
- Ground teams are primed and ready for a spectacular air show here as the Genesis
sample return capsule speeds its way through the Earth's atmosphere today and
is snared in midair over remote desert landscape.
NASA's Genesis spacecraft
is bringing back particles of solar wind collected by ultra-pure wafers of gold,
sapphire, silicon and diamond carried onboard the deep space probe.
"All systems are go.
We're doing quite well and on our way to Earth," said Don Sevilla, Genesis
payload recovery lead from the Jet Propulsion Laboratory (JPL) in Pasadena,
California. The spacecraft was accelerating en route to Earth and will dive
into the atmosphere at about 25,000 miles per hour, he said during a Tuesday
press briefing here.
At that speed, the 450-pound
sample return capsule carries with it the same kinetic energy as a 4.5 million
pound freight train slicing into the air at 80 miles per hour, said Bob Corwin,
Genesis capsule recovery team chief from Lockheed Martin, designer and builder
of the spacecraft.
"You can see the job
the atmosphere has to do in slowing the capsule down to the point where we can
deploy parachutes," Corwin said.
No take two
The Genesis return sample
capsule begin the final plunge at roughly 8:55 a.m. Pacific Daylight Time (11:55
a.m. ET) over northern Oregon, experiencing peak heating conditions as it decelerates
near the Oregon/Nevada border en route to the U.S. Air Force's Utah Test and
Training Range (UTTR).
Helicopter teams are practiced
and prepared to attempt midair capture of the Genesis sample-carrying container
as its glides high over the desert terrain under a parachute-like "wing"
called a parafoil.
"Both the pilots and
crews are ready to go," said Cliff Fleming, pilot of the Genesis primary
capture helicopter from South Coast Helicopters of Santa Ana, California.
Fleming said that two retrieval
helicopters are ready to make multiple tries at snaring the capsule in midair
-- from roughly 9,000-foot altitude down to just 500 feet above the ground.
"We feel pretty confident,"
Fleming said. "What's hard about it...it's the pressure. This is a one time
chance and there's no take two."
One atom at a time
Purpose of the midair retrieval
is to avoid a ground impact that could well shatter the delicate wafers that
hold the solar particles. Those wafers have been exposed for over two years
in space. They are likely pinged and pitted by micrometeorites, making them
all the more fragile, JPL's Sevilla said.
If the sample return canister
does hit the ground, it's not a loss of the mission. However, the resulting
impact would turn the sample container into, basically, "a can of glass,"
Sevilla said, making it difficult to extract Genesis science data.
"It's not a mission
failure, but they'll be hits on the science side if we end up parachuting to
the ground," noted Don Burnett, Genesis principal investigator from the
California Institute of Technology.
Genesis has collected solar
material "one atom at a time," he told SPACE.com. Several major
facilities have been established, dedicated to in-depth studies of the collected
solar particles. In all there are roughly 15 laboratories around the world,
he pointed out, getting ready to analyze the materials brought back to Earth
by Genesis.
Let the science begin
Once the Genesis sample
return capsule is snagged by helicopter, it is first lowered gently onto a ground-secured
tarp. At that location, personnel will remove the parafoil for easy airlift
of the Genesis canister to a specially fabricated cleanroom and work area at
the Dugway Proving Ground.
Ground handlers are set
to cut hinges that hold together the return capsule's backshell/heat shield
segments, revealing the enclosed Genesis sample-carrying canister.
The canister is then purged
with nitrogen, flushed of gases that have entered the canister during its fall
through the upper atmosphere. In the next day or so, the canister will be lifted
by crane and put into a container for truck transport, "and we're off to
Houston and the science begins," Burnett said.
Pass the collection plates
A team of specialists at
NASA's Johnson Space Center (JSC) in Houston, Texas will receive the Genesis
sample container. At the space agency facility, "the cleanest cleanroom
in the NASA system," is ready for use, said Carlton Allen, JSC's Astromaterials
Curator.
Allen said what the Genesis
sample canister collection plates have caught will be viewed for the first time
early next week in the JSC ultra-cleanroom.
The spacecraft was launched
on August 8, 2001, taking three months time to cruise to its solar particle
sampling position nearly one million miles from Earth.
Genesis has been to a unique
spot in space, Allen said. During two years of loitering at the Lagrange 1 point,
the radiation flux, as well as micrometeorite hits the spacecraft has endured
will be of great interest, he said.
"We ought to learn
a great deal about what that part of the space environment is like...irregardless
of what we're learning about the Sun," Allen said.
Valuable engineering data
David Lindstrom, Genesis
program scientist at NASA Headquarters in Washington, D.C., said the probe's
tour of duty in deep space and return to Earth also brings back valuable engineering
data to help design future spacecraft.
Following the Genesis mission,
NASA's Stardust mission will also drop into the Utah Test and Training Range
in about 16 months time, hauling with it comet and interstellar dust particles.
"There's probably a
lot more sample return missions down the road. Genesis is laying the groundwork
for much of that," said Lockheed Martin's Corwin. "There's quite a
lot going on here...a lot of firsts to Genesis, both from execution of the mission,
as well as the science coming back," he said.
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