Studying the effect of UV radiation on carbon in meteorites
Arjen Boosman
Methane (CH4) is a strong greenhouse gas that is abundant on Earth. ~90% of terrestrial CH4 is produced by microorganisms. The discovery of CH4 in the atmosphere of Mars has led to widepsread speculation and several theories on its origin, including life! One of the other methods at which CH4 can be produced is the irradiation of carbonaceous chondrites (a class of meteorites). An expected ~ 106kg of meteorites reaches the Martian surface each year. Irradiation of this carbon rich material has been proven to yield CH4 (Keppler et al., 2012). While this is probably too small of a CH4 source to produce the few ppb’s of CH4 in the Martian atmosphere, we conduct a study to find which organics, including CH4 can be produced by photolysis of meteoritic organic carbon. We use CRDS and PTR-TOF-MS to measure the emitted organics in the gas phase, and NanoSIMS to measure organic carbon and its degradation in meteorite material in situ. In the near future, we will perform isotopic analysis of the produced organics to determine the process’ isotopic fingerprint.
