Chemical Implications of Electric Discharge for Methane in the Martian Atmosphere - Laboratory Simulations

Methane is still one of the most debated species in the martian atmosphere. The search for methane in the martian atmosphere has led to variable concentration estimates, from none to 10 ppbv globally. Different theories have been proposed to explain this variability. One proposed destruction mechanism for methane is breakdown through electric discharge induced chemistry. This discharge could be induced on Mars by electric fields generated by dust particle interaction in dust storms and dust devils. Theoretical models describe the processes that could occur in the martian atmosphere and provide estimates of breakdown voltages and chemical reaction schemes of breakdown products. In order to test these predicted breakdown scenarios, we have built a laboratory setup to simulate these processes. With this setup we will not only measure the breakdown rates and products of methane in the martian atmosphere, but it also enables to measure formation products such as hydrogen peroxide. Hydrogen peroxide has been suggested to play a role in the desctruction of organics on the martian surface. We will present the first results from our experiments as well as the implications for the methane cycle on Mars.