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Hi, I'm David Bish, co-investigator on the
CheMin instrument on the Mars Science Laboratory

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and this is your Curiosity rover update.

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We have been spending some time in an area
called Rocknest, and this week we delivered

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a scoop of a dune to Curiosity.

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CheMin performs X-ray diffraction measurements
on powdered rocks and soil samples.

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An X-ray diffraction is the best method for
telling us what minerals are present in a

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rock or a soil because it is sensitive to
the arrangements of atoms in minerals.

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As the X-rays strike the soil sample, CheMin
shows us how mineral crystals distinctively

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interact with X-rays, and this image shows
us our first X-ray diffraction results.

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The diffraction signals appear on the detector
as rings that represent the fingerprint of

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the minerals.

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The rings tell us not only what minerals are
present in the soil and but also how abundant

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they are.

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The CheMin data provide us distinctive signatures
of the minerals plagioclase feldspar, pyroxenes,

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and olivine.

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Peridot is a variety of olivine.

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Just keep in mind that the olivine in the
soil sample is much smaller than these crystals.

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Roughly half of the soil consists of poorly
crystalline material, such as volcanic glass.

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Thus, this Martian soil appears very similar
to some weathered basaltic soils that we see

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on Earth, in places like the flanks of Mauna
Kea, Hawaii

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You can appreciate how revolutionary CheMin
is when you consider that instruments of this

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type on Earth are typically about the size
of a double-wide refrigerator and the CheMin

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instrument on the Mars Science Laboratory
is about the size of a shoebox.

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CheMin has been modified for use on Earth
in places such as Antarctica and the Arctic.

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It’s also been applied for detection of
counterfeit pharmaceuticals around the world

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and a modification of the instrument has been
used in archeological studies to help us understand

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the nature of surfaces and how might we protect
them.

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In the coming weeks and months, we’re excited
to measure more X-ray diffraction data on

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soils and rocks to tell us more about the
geology of Gale Crater.