Nasa finds Mars rock that 'may have hosted life', with mysterious 'features we've never seen before'
26 July 2024, 15:46
Nasa scientists have found a rock on Mars they believe may have hosted life.
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The US space agency's Perseverance rover found a rock that "exhibits chemical signatures and structures that could possibly have been formed by life billions of years ago".
The scientists said that they had not found direct signs of life on the planet, such as fossilised microbes, but that the arrow-shaped rock had "features we'd never seen before".
They added that the rock "contains fascinating traits that may bear on the question of whether Mars was home to microscopic life in the distant past".
The rock has several off-white spots with black rings around a millimetre in diameter. These have been dubbed "leopard's spots".
The rock also has white stripes that contain calcium sulphate, and reddish areas that have hematite, which is a reddish material that gives Mars a rusty colour.
The black rings around the white spots contain iron and phosphate.
David Flannery, an astrobiologist and member of the Perseverance science team, said: "These spots are a big surprise".
He added: "On Earth, these types of features in rocks are often associated with the fossilized record of microbes living in the subsurface."
Nasa said the spots are caused by a chemical reaction that change the colour of the rocks.
The agency said: "Reactions of this type can be an energy source for microbes, explaining the association between such features and microbes in a terrestrial setting".
The rock was named Cheyava Falls after a waterfall in the Grand Canyon.
Ken Farley, Perseverance project scientist, said: "On the one hand, we have our first compelling detection of organic material, distinctive colorful spots indicative of chemical reactions that microbial life could use as an energy source, and clear evidence that water — necessary for life — once passed through the rock.
"On the other hand, we have been unable to determine exactly how the rock formed and to what extent nearby rocks may have heated Cheyava Falls and contributed to these feature".
