I will take it. Any sample is superior to no sample and we are
developing a spectrum of samples that could not be replicated with an
actual expedition to Mars. In the meantime more eyeballs are getting
familiar with the necessary characteristics and the desert regions
are becoming more productive.
In the meantime these are data points that help in piecing things
together for our expeditions to the planet.
Most ejecta will be part of a substantial event and that likely means
that a lot of material went into space at the same time. Most of
this will be from impact events. The low gravity and limited
atmosphere on Mars and the Moon make this practical.
Martian rock from
Sahara desert unlike others
By ALICIA CHANG, AP
Science Writer
Updated 4:53 pm,
Thursday, January 3, 2013
This image provided
Carl Agee, University of New Mexico, shows a rock from Mars that
landed in the Sahara Desert. An examination of the Martian meteorite
known as NWA 7034 determined it is 2.1 billion years old and is
water-rich. Photo: University Of New Mexico, Carl Agee / AP
http://www.sfgate.com/news/science/article/Martian-rock-from-Sahara-desert-unlike-others-4164854.php
LOS ANGELES (AP) —
Scientists are abuzz about a coal-colored rock from Mars that landed
in the Sahara desert: A yearlong analysis revealed it's quite
different from other Martian meteorites.
Not only is it older
than most, it also contains more water, tests showed. The
baseball-size meteorite, estimated to be 2 billion years old, is
strikingly similar to the volcanic rocks examined on the Martian
surface by the NASA rovers Spirit and Opportunity, which found
water-bearing minerals.
"Here we have a
piece of Mars that I can hold in my hands. That's really exciting,"
said Carl Agee, director of the Institute of
Meteoritics and curator at the University of New
Mexico who led the study published online Thursday in the
journal Science.
Most space rocks
that fall to Earth as meteorites come from the asteroid belt, but a
number can be traced to the moon and Mars.
Scientists believe
an asteroid or some other large object struck Mars, dislodging
rocks and sending them into space. Occasionally, some plummet
through Earth's atmosphere.
Short of sending a
spacecraft or astronaut to the red planet to haul back rocks,
Martian meteorites are the next best thing for scientists seeking
to better understand how Earth's neighbor transformed from a
tropical environment to a frigid desert.
About 65 Martian
rocks have been recovered on Earth, mostly in Antarctica or the
Sahara. The oldest dates back 4.5 billion years to a time when Mars
was warmer and wetter. About half a dozen Martian meteorites are
1.3 billion years old and the rest are 600 million years
or younger.
The latest meteorite
NWA 7034 — nicknamed "Black Beauty"— was donated to
the University of New Mexico by an American who bought it from a
Moroccan meteorite dealer last year.
Researchers
performed a battery of tests on the meteorite and based on its
chemical signature confirmed that it was blasted to Earth from
Mars. At 2.1 billion years old, it's the second-oldest known
Martian meteorite that formed from a volcanic eruption.
There's also
evidence that it was altered by water. Though the amount released
during heating was small — 6,000 parts per million — it was
still much more than other Martian meteorites. Scientists said this
suggested there was interaction with water near the surface during
a time when the planet was mostly dry and dusty.
More tests are under
way to determine how long the rock floated in space and how long it
had been sitting in the Sahara.
University of
Alberta meteorite expert Chris Herd said the find
was welcome since most Martian rocks that rain on Earth tend to be
younger. And the latest find does not appear to be too
contaminated, he said.
"It's fairly
fresh. It hasn't been subjected to a whole lot of weathering,"
said Herd, who had no role in the research.
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