The samples were extracted by the rover in the Gale Crater, the site of an asteroid impact that occurred about 3.6 billion years ago.
NASA researchers studying Mars through the Curiosity rover have made a discovery related to possible evidence of life on the Red Planet, Live Science reports.
During the course of its mission, Curiosity retrieved two samples of mudstone, a sedimentary rock containing clay, with the media outlet pointing out that clay is both “a good signpost towards evidence of life” (since it is usually created when “rocky minerals weather away and rot after contact with water”) and an excellent material for storing microbial fossils.
However, having analysed the samples, the researchers concluded that the material extracted from one of the patches contained “only half the expected amount of clay minerals,” and instead had a “greater quantity of iron oxides.”
As the media outlet notes, scientists named brine as the likely culprit.
At the same time, John Grotzinger, study co-author and a geology professor at Caltech, noted that diagenesis – the process of chemical changes in sediments – “may erase the signs of life in the original lake”, it also “creates the chemical gradients necessary to support subsurface life,” so the team is really excited about their discovery.