[meteorite-list] Genesis, Stardust Samples Sent Out For Study
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed Feb 15 12:29:52 2006
Space samples sent out for study
Scientists begin their analysis of Sun samples from the crashed Genesis
probe and comet samples returned by Stardust.
February 14, 2006
The soft landing of the Stardust capsule in January contrasted sharply
with the Genesis probe's crash 16 months earlier. Despite this
difference, scientists are busy analyzing the samples each spacecraft
returned to Earth.
After a 3-year journey collecting solar particles, Genesis returned to
Earth in similar fashion to Stardust. But a failed parachute sent the
craft careening into the desert floor at 193 mph (311 kilometers/hour).
Delicate collector panels were left in shards, covered with desert
debris. "We expected to have 250 samples," says principal investigator
Don Burnett. "Now, we have 15,000 pieces to work with."
That's plenty to supply the world's scientific community with particles
from the solar wind, says Burnett, but the work is made difficult by the
contamination from Genesis' rough landing, and from internal
contamination from the spacecraft itself. "It's been slow, but we
haven't given up on any of our goals. It's just that everything is a lot
harder now," he adds.
Already, researchers have identified ions originating from the Sun.
"There are three kinds of solar wind," Burnett explains. "The spacecraft
was able to move the collection panels in and out to get data from
different types. We've already analyzed noble gases [helium, neon and
argon], as they are not too sensitive to this type of contamination. We
want to measure the ratios of isotopes of elements from the Sun's
surface, and we now have direct data. We're getting interesting and
important results even at this early stage."
After the chaotic events of the spacecraft's landing, scientists
anxiously awaited the release of Genesis samples. Over 100 samples have
already been sent to nearly 20 labs around the globe. As
Lockheed/Martin's Benton Clark, an investigator on the Stardust team,
says, "We want everybody to know that Genesis is a great success." After
a nearly disastrous return to Earth, the painstaking work of countless
engineers and researchers has salvaged the mission. Genesis promises to
revolutionize our knowledge of the Sun, the solar wind, and even the
beginnings of our solar system.
Stardust samples are already on their way to investigators throughout
the world, but the mission's dangerous touchdown was even more
nerve-wracking in light of Genesis' landing. Last month, Stardust's
return capsule streaked across the sky above the Utah desert and landed
gently on a muddy plain. The craft carried samples of Comet Wild 2 and
interstellar dust. "The entire sky lit up in a golden-red glow," says
He was also in Houston to witness the capsule's opening at the Johnson
Space Center. Tennis racquet-size collectors with aerogel surfaces used
one side to collect interstellar dust, while the opposite face was
exposed to Comet Wild 2's coma.
The interstellar dust side was revealed first. "It was absolutely
pristine, which one would expect since the particles are thought to be
on the order of one micron," says Clark. But he was more delighted to
see the comet side, unveiled 15 minutes later. "You could see big
splotches, almost like bird droppings." By studying comets, which date
to the solar system's formation, scientists hope to understand how the
solar system has evolved.
Michael Carroll is a science writer and astronomical artist, and author
of nearly 20 children's science books. He lives with his family in Colorado.
Received on Wed 15 Feb 2006 12:28:08 PM PST