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A few meteorites proved to be of a more prominent origin:
the so-called planetary meteorites, genuine pieces of the Earth's own
Moon, and the planet Mars. Massive chunks of matter have been blasted
off of their respective parent body's surface by violent impacts, and
catapulted into space. Some of these pieces finally went into a
Earth-crossing orbit, and landed on Earth in form of meteorites.
Planetary meteorites are ultra-rare, and just about one out of thousand
meteorite finds or falls has its origin on the Moon, or on planet Mars. |
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Genuine Mars & Moon Rocks: Planetary Meteorites
In the early 1980s, Japanese and American researchers discovered the
first lunar meteorites in the ice fields of Antarctica - genuine pieces
of the Earth's Moon! Subsequently, several other "lunars" have been
recovered from the hot deserts of Australia, Africa, and Oman, bringing
the total number of all known lunar meteorites to about 40, excluding all
probable pairings. All of these meteorites were found to exhibit mineral
compositions similar to the samples returned by the Apollo and Luna
missions, proving their lunar origin beyond any doubt.
Lunar meteorites are of major scientific importance because most of them
originate from areas of the Moon that were not sampled before. Most
lunar meteorites in our collections have been blasted off of the lunar
highlands that cover the far side of the Moon. Only a few lunars have their
origin in the smooth lowlands, the lunar maria of the near side of the Moon
which served as the preferred landing sites for the Apollo missions. Please
visit the lunar section
of this site for much more detailed information.
The meteorites of the SNC group, named for the 3 witnessed falls of
Shergotty, Nakhla, and Chassigny, are even more fascinating since they
represent genuine pieces of the planet Mars. With crystallization ages
between 1.35 and 0.15 billion years, most SNC group members are
exceptionally young compared to other achondrites. Obviously, they formed
on a parent body that has retained its igneous activity until very recent
times, suggesting that the source of these strange rocks is a planet.
In the 1980s, the discovery of trapped gas inclusions inside several SNC
members provided a final answer. Based on the data obtained by the
Viking probes, which landed on Mars in 1976, the composition of this
trapped gas is more or less identical to the composition of the martian
atmosphere, convincing most scientists that the SNC members are genuine
samples of our red neighbor. The latest proof of martian origin
for the SNC group has been delivered by the Mars Exploration Rover
“Opportunity” in the year 2005: the rover studied a rock dubbed “Bounce”
at Meridiani Planum with mineral compositions similar to EETA 79001,
providing another strong link between Mars, and the meteorites of the
SNC group. Consequently, the SNC members are also known as martian
meteorites. Please visit our
martian section
to learn more about these unusual and enigmatic rocks from space. |
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