Studying the effect of UV radiation on carbon in meteorites

Seraina Holinger

The detection of organic matter is a major focus of astrobiological space missions that aim to identify past or present life on the surface of Mars. Organic matter is delivered to the surface of the terrestrial planets through infall from meteorites and meteoritic dust but the fate of the meteoritic carbon is poorly understood. Photolysis by ultraviolet radiation (UV) is a potentially important mechanism for breakdown and recycling of organics, producing gases, including methane, and leaving behind an unidentified solid residue, which may provide an organic substrate for a potential biosphere on Mars.
The goal of this project is to investigate the full life cycle of meteoritic carbon under irradiation with high energy UV light. Measurements will be carried out using a wide range of state of the art analytical techniques including nano-scale secondary ionization mass spectrometry (NanoSIMS), Secondary Electron Microscopy (SEM), cavity ring-down spectroscopy (CRDS), high precision isotope ratio mass spectrometry
and other gas chromatographic techniques. The results are relevant for the interpretation of detections made by the Sample Analysis at Mars instrument on board the Curiosity Rover.