As NASA announced last week, and has now explained even better in their latest video,
"Much of Mars is covered with dust, and we had an incomplete understanding of its mineralogy," said David Bish, CheMin co-investigator with Indiana University in Bloomington. "We now know it is mineralogically similar to basaltic material, with significant amounts of feldspar, pyroxene and olivine, which was not unexpected. Roughly half the soil is non-crystalline material, such as volcanic glass or products from weathering of the glass. "
So, Curiosity keeps finding rocks like those on Earth which were formed by underwater vulcanism. My interest in this unfolding research is piqued by the fact that, earlier this year I visited the Hawaiian Islands for the first time and I was really engaged by the geology. By strange coincidence my vacation next year includes time in the Azores, which is sort of the Hawaii of the Atlantic, geologically speaking, a product of vulcanism and mid-ocean tectonics.
NASA has not further commented on the "bright grains" visually identified in the sample analyzed by CheMin, but one might speculate, at least, that the presence of these crystalline minerals could explain the observations.
Mrs. Left seemed very pleased to hear the news about olivine in the sample, aka peridot, her birthstone, and was quick to point out that none of the other birthstones have been found on other planets.
I've transcribed the video for those in need. It's out in the tall grass.
For all of my Mars diaries and all things Mars on Daily Kos go to Kossacks on Mars.
Transcript. All errors are mine.
Hi. I'm David Bish, Co-Investigator on the CheMin Instrument on the Mars Science Laboratory and this is your Mars Curiosity Rover update.
We've been spending time in an area called Rocknest and this week we delivered a scoop of a dune to Curiosity. CheMin performs what we call X-ray diffraction measurements of powdered rocks and soil samples. And x-ray diffraction is the best method for telling us what minerals are present in a rock or soil because it is sensitive to the arrangement of atoms in minerals. As the x-rays strike the soil sample, CheMin shows us how mineral crystals distinctively interact with x-rays.
And this image shows our first x-ray diffraction results. The diffraction signals appear on the detector as rings that represent the fingerprint of the individual minerals. The rings tell us not only what minerals are present in the soil but also how abundant they are.
The CheMin data provide us with distinctive signtures of the minerals feldspar, pyroxines and olivines. Peridot is a variety of olivine. Just keep in mind that olivine in the soil sample is much smaller than these crystals.
Roughly half of the soil consists of poorly crystalline material such as volcanic glass. Thus, the Martian soil appears very similar to some weathered basaltic soils that we see on Earth in places like the flanks of Mauna Kea Hawaii.
You can appreciate how revolutionary CheMin is when you consider that instruments of this type on Earth are typically the size of a double wide refrigerator and the ChemMin instrument on the Mars Science Laboratory is about the size of a shoebox.
CheMin has been modified for use on Earth in places such as Antarctica and the Arctic. It has also been applied for the detection of counterfeit pharmaceuticals around the World and a modification of the instrument has been used in archeological studies to help us understand the nature of the surfaces and how we might protect therm.
In the coming weeks and months we are excited to measure more x-ray diffraction data on soils and rocks to tell us much more about the geology of Gale Crater.
This has been your Curiosity Rover report. Stay tuned for further updates.