Rare meteorite promises glimpse into dawn of creation
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This image of the meteor's smoke trail was captured by Ewald Lemke of Atlin, British Columbia, on January 18
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March 17, 2000
Web posted at: 11:38 a.m. EST (1638 GMT)
By Richard Stenger
CNN Interactive Writer
JOHNSON SPACE CENTER, Texas (CNN) -- Pieces of a meteor that stunned viewers when it exploded in a giant fireball earlier this year could help explain the formation of solar system and life on Earth, scientists said this week.
U.S. and Canadian space geologists pronounced the unusually pristine pieces of the space rock as one of the most important meteorite finds in more than 30 years.
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An anonymous collector found the fragments in the frozen Yukon and kept them in cold storage, giving scientists a unique sample of the early solar system.
Scientists say the fragments are from a rare type of meteorite that contains a variety of complex organic compounds.
"It's a once in a lifetime deal. No one has ever recovered a meteorite and kept it this pristine. It may never happen again," NASA mineralogist Michael Zolensky said.
The 4.5 billion-year-old fragments will offer a glimpse into the original composition of the solar system before the planets formed, said Zolensky, who is studying a few samples at NASA's Johnson Space Center in Houston.
"These meteorite fragments are of immense scientific value and interest," echoed Dr. Richard Herd, curator of National Collections for the Geological Survey of Canada, in a statement.
Carbonaceous chondrite spells 'life'
The meteorite streaked across the night sky over the Yukon in
January, producing sonic booms, green flashes, a foul odor
and a detonation with as much energy as several kilotons of
TNT.
"It was probably one of the brightest fireballs over the
Earth in the past decade," Zolensky said.
The crumbly, black, porous rock fragments have charred,
pocked surfaces and retain the smell of sulfur. They look
like used charcoal briquettes.
But they actually are examples of carbonaceous chondrite, a
rare meteorite type that holds many kinds of carbon and organics,
the basic ingredients in the primordial soup from which life
arose.
Only about 2 percent of meteorites known to have reached
Earth are carbonaceous chondrites, which tend to deteriorate
when they enter the atmosphere or during weathering on the
ground.
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NASA mineralogist Michael Zolensky holds one of the recovered fragments of the Yukon meteor
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'Next best thing to mission to asteroid'
The last time a similar carbonaceous chondrite fell to Earth
and was recovered was 31 years ago. But like most others,
those fragments thawed, which may have allowed some of their
secrets to escape, Zolensky said.
"No one has had a chance to (study) a frozen meteorite like
this one. We expect to find a lot of neat new things that
previously had been lost," he said. "It's the next best thing
to having a mission go to an asteroid."
Because of the violence of the meteorite fireball, Zolensky said,
"I never thought there would be a high chance of recovery of
anything but dust."
A NASA research plane flew over the area several days after
the blast, combing the air to collect particles from the
meteorite trail. Those results are pending.
Cool-thinking collector bagged the prize
The meteorite finder, who wished to remain anonymous,
recovered two pounds of fragments from the snow-covered
ground of the Yukon, which provided near-ideal conditions for
preservation.
He kept the fragments continuously frozen in plastic bags
and loaned them to the Geological Survey of Canada in Ottawa,
which provided a pound for the Johnson Space Center to study.
They are the only newly fallen meteorite fragments found and
transferred to a laboratory without thawing, NASA said.
Keeping them constantly frozen reduces the risk that organics
and other volatile compounds will escape.
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RELATED SITES:
ANSMET - The Antarctic Search for Meteorites
Mars Meteorite Home Page (JPL)
Nine Planets: Meteorites and Impacts
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