- A team of NASA-sponsored meteorite hunters has discovered
what it believes is an ancient chunk of Mars -- on Earth.
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- The team of Antarctic explorers came across the 1.5-pound
black rock last December while scouring for meteorites in the Transantarctic
Mountains, about 466 miles from the South Pole. A subsequent analysis by
the Smithsonian Institution revealed that the rock's mineralogy and texture
are "unmistakably Martian," according to a statement released
Wednesday by NASA.
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- The rock likely exploded off the surface of the red planet
during an asteroid impact about 11 million years ago, NASA said. After
speeding through space for an unknown period, it eventually burned through
Earth's atmosphere and landed in Antarctica, where it has remained until
now as a time capsule full of information about Mars.
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- Scientists believe the discovery will not only give them
a better understanding of the terrain that NASA's Mars rovers are currently
exploring, but that it may also help them get glimpses of what Mars' atmosphere
is like. The meteorite contains tiny pockets of trapped gas, which an analysis
shows to be similar to gas detected on Mars itself by NASA's Viking probes
in 1976.
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- Until now, only 28 Martian meteorites were known to have
been discovered on Earth, according to NASA. December's find is considered
to be especially rare because it belongs to a group of Martian meteorites
known as Nakhlites -- volcanic rocks that formed more than 1.3 billion
years ago in a Martian lava flow. There are only eight known Nakhlites
in the world, including this one. The first was found in Nakhla, Egypt,
in 1911.
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- The latest meteorite was found by the Antarctic Search
for Meteorites program, which is sponsored by NASA, the National Science
Foundation and the Smithsonian Institution. Antarctica is considered an
ideal place to search for meteorites because they stand out against the
bluish-white snow that covers much of the continent, and because most of
the rocks formed on Earth are buried nearly two miles under that snow.
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- The Martian meteorite will now be stored and managed
by the Astromaterials Curation department at NASA's Lyndon B. Johnson Space
Center in Houston, where all of NASA's samples are kept.
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