High-Power Laser-Plasma Chemistry in Planetary Atmospheres

Currently generally accepted opinion considering Earth’s early atmosphere as a mildly reduced gas mixture of molecular gases represents a crucial difficulty for the classical Miller's experiments carried out originally in a strongly reducing gaseous mixture. In the weakly reducing environment they give a poor yield of amino acids and other compounds of relevance to the chemical evolution. In our study we intended to simulate impact shocks and lightning in the mixtures of molecular gases modeling Earth’s early atmosphere with the help of focused beam from high-power laser systems. The main goal of our project is to diagnose the laser-produced plasma, determine its basic physical characteristics and investigate their links to the chemical action of the laser spark in such a reaction system. Varying laser-plasma interaction conditions and composition of the gas mixtures the chemical evolution during various stages of Earth’s early atmosphere evolution was investigated in dependence on the kind and the energetics of initializing high-energy density event (e.g., cometary impact).