Students from St Bernard High School along with Fellow Connor Ballard from the Mullard Space Science Laboratory, UCL, have taken a significant step towards understanding the potential to identify life on Mars by conducting a unique experiment using microbialites from Lake Salda, Turkey! These microbialites, which are ancient structures formed by microorganisms, form similar carbonate deposits to those identified on Mars, but the origin of the Martian carbonates is still unknown!

The students exposed these microbialites to Martian-like conditions in a stratospheric balloon experiment, simulating the low pressure, temperature, and radiation found on the Red Planet. By analysing the microbialites' response to these harsh conditions, they aimed to gain insights into the survival limits of terrestrial life and the possibility of extraterrestrial microbial communities.

The experiment yielded promising results! They detected organic molecules, including those associated with DNA in the microbialites, which deteriorated after exposure to Martian conditions, suggesting that detecting signs of life in Martian carbonate deposits may be difficult at the surface and we may need to focus on deposits shielded from the harsh Martian radiation environment. This study supports the need to return deposits from below the surface to understand if microbial activity could have played a significant role in shaping the Martian landscape.

These findings provide insights into the effect of Martian conditions on the preservation of biosignatures, and have implications for the upcoming Rosalind Franklin rover, which hopes to search for signs of life in the Martian subsurface using a 2m drill!