[meteorite-list] Mars Meteorites Linked to Rock at Meridiani

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:31:14 2004
Message-ID: <200404151705.KAA03632_at_zagami.jpl.nasa.gov>

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040414a.html

Press Release Images: Opportunity
April 14, 2004

'Bounce' and Shergotty Share Common Ground

This illustration compares the light
signature or spectrum of "Bounce," a rock
at Meridiani Planum, to that of a martian
meteorite found on Earth called Shergotty.
Bounce's spectrum, and thus mineral
composition, is unique to the rocks studies
so far at Merdiani Planum and Gusev Crater,
the landings sites of the Mars Exploration
Rovers Opportunity and Spirit. However, the
results here indicate that Bounce is not a
one-of-a-kind rock, but shares origins with
Shergotty. Shergotty landed in India in
1865. Bounce's spectra were taken on sol 67
by Opportunity's Moessbauer spectrometer.

Image credit: NASA/JPL/Cornell/University of Mainz

----------------------------------------------------------

Meteorite Linked to Rock at Meridiani

This meteorite, a basalt lava rock nearly
indistinguishable from many Earth rocks,
provided the first strong proof that
meteorites could come from Mars. Originally
weighing nearly 8 kilograms (17.6 pounds),
it was collected in 1979 in the Elephant
Moraine area of Antarctica. The side of the
cube at the lower left in this image
measures 1 centimeter (0.4 inches).

This picture shows a sawn face of this
fine-grained gray rock. (The vertical
stripes are saw marks.) The black patches
in the rock are melted rock, or glass,
formed when a large meteorite hit Mars near
the rock. The meteorite impact probably
threw this rock, dubbed "EETA79001," off
Mars and toward Antarctica on Earth. The
black glass contains traces of martian
atmosphere gases.

The Mars Exploration Rover Opportunity has
discovered that a rock dubbed "Bounce" at
Meridiani Planum has a very similar mineral
composition to this meteorite and likely
shares common origins. Bounce itself is
thought to have originated outside the area
surrounding Opportunity's landing site; an
impact or collision likely threw the rock
away from its primary home.

Image credit: NASA/JSC/JPL/Lunar Planetary Institute

------------------------------------------------------

'Bounce' and Martian Meteorite of the Same Mold

These two sets of bar graphs compare the
elemental compositions of six martian
rocks: "Bounce," located at Meridiani
Planum; EETA79001-B, a martian meteorite
found in Antarctica in 1979; a rock found
at the Mars Pathfinder landing site;
Shergotty, a martian meteorite that landed
in India in 1865; "Adirondack," located at
Gusev Crater; and "Humphrey," also located
at Gusev Crater. The graph on the left
compares magnesium/iron ratios in the
rocks, and the graph on the right compares
aluminum/calcium ratios. The results
illustrate the diversity of rocks on Mars
and indicate that Bounce probably shares
origins with the martian meterorite
EETA79001-B. The Bounce data was taken on
sol 68 by the alpha particle X-ray
spectrometer on Mars Exploration Rover
Opportunity.

Image credit: NASA/JPL/Cornell/Max Planck Institute
Received on Thu 15 Apr 2004 01:05:28 PM PDT