Meteorite points to life on Mars

A tiny fragment of Martian meteorite has added to the growing body of evidence that the red plant might have hosted life. Upon this meteorite, researchers found a cell-like structure which once held water. The structure looked like a fossilised biological cell from Earth, but definitely came from the red planet, say researchers from the University of Manchester and the National Technical University of Athens. The ‘cell’ – a biomorphic ovoid structure – was found by Dr Elias Chatzitheodoridis in Nakhla, a Martian meteorite made of nanocrystalline iron-rich saponitic clay and amorphous material. The structure was imaged in unprecedented detail by Dr Sarah Haigh, who was able to reveal the atomic layers of materials inside the meteorite, and analysed by Professor Ian Lyon of the School of Earth, Atmospheric and Environmental Sciences at Manchester. A wide range of spectroscopic techniques pointed to a cell-like structure. “In many ways it resembled a fossilised biological cell from Earth but it was intriguing because it was undoubtedly from Mars,” said Lyon. “Our research found that it probably wasn’t a cell but it did once hold water, water that had been heated, probably as a result of an asteroid impact.” The findings, published in Astrobiology, are significant because it adds to the mounting evidence that beneath the surface, Mars does provide all the conditions for life to have formed and evolved. It also adds to the evidence suggesting that large asteroids once hit the planet in the past, producing long-lasting hydrothermal fields that could sustain life if it ever emerged. “We have been able to show the setting is there to provide life,” said Lyon. “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 still exist.” The team are now investigating new secondary materials in the meteorite and searching for possible bio signatures which provide scientific evidence of life, past or present. A conspicuous clay ovoid in Nakhla: Evidence for subsurface hydrothermal alteration on Mars with implications for astrobiology