Space.com report published yesterday, scientists reveal their findings after examining a meteorite that fell to Earth last year. The meteorite, officially named Tissint, shows clear indications it is of Martian origin and although it isn't the first Martian meteorite that's been found on Earth, it is the newest one. This means that it is relatively free of any local contamination, and would therefore promise a fairly clean view of what Mars' ancient environment was like.In a
"It's really a great sample if you're interested in studying something that has more or less been delivered straight from Mars, uncontaminated, to the Earth," said Dr. Carl Agee, a Professor and Meteorite Curator at the University of New Mexico, according to ScienceNews.
Tissint is the latest of a total of 88 meteorites classified as a Shergottite, a piece of Martian igneous rock that was blasted from the surface of Mars — likely by a asteroid strike —about 700,000 years ago. It fell to Earth in a meteorite swarm on July 18th of last year and according to The Meteoritical Society, the recovered pieces of the meteorite totaled about 7 kilograms. Less than 600 grams of that is now held by various institutions for study. The rest is owned by various collectors.
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The glassy black material of Tissint was found to contain bubbles and channels of ancient Martian atmosphere, as well as minerals from the planet's surface, locked away inside as the impact that launched it into space melted parts of the rock around them. The structure of the meteorite shows that it is a volcanic rock, with high concentrations of a green mineral called olivine, and it was likely formed in the interior of Mars. However, it also shows evidence of being on the surface, as well as evidence of weathering, possibly by water. This adds another potential piece of evidence for the presence of liquid water on Mars' surface at some point in the past, as the meteorite was not on Earth long enough to experience weathering of that kind from local sources of water.
"It's sort of like having a little Martian environment tucked away inside that meteorite," Agee said.
In May of this year, another report was published about Tissint, explaining the presence of organic molecules inside the rock.
"Mars apparently has had organic carbon chemistry for a long time," said Andrew Steele, lead author of the May report and a microbiologist at the Carnegie Institution of Washington, told SPACE.com.
However, they discovered that the organic molecules were formed through volcanic processes rather than biological ones.
"When the minerals crystallized from the magma, they trapped carbon in them, and over time, organic compounds formed within these mineral bottles," Steele said.
So, whereas this isn't direct evidence that life once existed on the Red Planet, Steele added that "on Earth, organic chemistry led to life, so what is the fate of this material on Mars, the raw material that the building blocks of life are put together from?"