Martian meteorite hints at possibility of life on Mars

A tiny fragment of a meteorite could move us a step closer to proving the existence of life on Mars, according to scientists.

The 1.3 billion-year-old Martian meteorite, known as Nakhla, has been found to contain a cell-like structure, which scientists can now confidently say once held water. The finding came about after Professor Ian Lyon of the University of Manchester teamed up with the Greek scientist Dr Elias Chatzitheodoridis, based at the National Technical University of Athens.

Dr Chatzitheodoridis had been investigating the rock when he found an unusual feature embedded deep within it. His first port of call was his long-time friend Professor Lyon, who helped him to identify the structure. Ian Lyon, a Professor of Cosmochemistry in Manchester’s School of Earth, Atmospheric and Environmental Sciences, said: “In many ways it resembled a fossilised biological cell from Earth but it was intriguing because it was undoubtedly from Mars.

“Our research found that it probably wasn’t a cell but that it did once hold water—water that had been heated, probably as a result of an asteroid impact.”

Despite its barren appearance, it has long been believed that Mars is capable of supporting life, or at least has been capable in the past. There is increasing evidence that beneath the surface, the planet provides all the conditions necessary to form and develop life. This latest finding also suggests that the Red Planet was heavily bombarded by large asteroids in the past, potentially producing long-lasting hydrothermal fields. These fields, commonly found on Earth in volcanic areas where magma meets hot water, could have sustained life on the planet.

Professor Lyon added: “We have been able to show the setting is there to provide life. It’s not too cold, it’s not too harsh. Life as we know it, in the form of bacteria, for example, could be there, although we haven’t found it yet. It’s about piecing together the case for life on Mars—it may have existed and in some form could exist still.”

The water-bearing feature was imaged in unprecedented detail by Dr Sarah Haigh, a lecturer in the School of Materials at the University of Manchester. A graphene-based method was used, revealing the atomic layers inside the meteorite. This combined approach will now be used to examine secondary materials within the rock.

Professor Lyon concluded: “Before we return samples from Mars, we must examine them further, but in more delicate ways. We must carefully search for further evidence.”