(Washington) The rover Perseverance NASA has made a major discovery by collecting a rock from Mars that may contain fossilized microbes, a major new step in the search for traces of ancient life on the Red Planet.
The rover took a sample of a rock called “Cheyava Falls” from the surface of Mars on July 21, shaped like an arrowhead and possibly containing fossilized microbes dating back billions of years, when water was present on the planet.
The red planet, whose current climate is extremely arid, had an abundance of rivers and lakes billions of years ago, which have now evaporated.
This enigmatic rock was found in the Neretva Valley, which once housed a river, and quickly got scientists excited.
And for good reason: three signs suggestive of ancient microbial life have been observed on its surface.
First, white veins formed by calcium sulfate run the length of the rock, NASA says, a sign that water was flowing through the rock at one point.
Between these veins is a central reddish zone that is full of organic compounds, according to an instrument on the rover, SHERLOC, which is used to identify biological signatures on rocks.
Finally, small light spots surrounded by black comparable to those of a leopard were observed. These are similar to spots associated with the presence of fossilized microbes, according to the analyses carried out by the PIXL instrument which studies the chemical composition.
“On Earth, these types of features in rocks are often associated with fossilized traces of microbes that lived underground,” says David Flannery, an astrobiologist and member of the science team at Perseverance.
To confirm that they are evidence of ancient microbial life, these samples will need to be analyzed in a laboratory on Earth. NASA plans to bring them back, thanks to another mission, scheduled for the 2030s.