title: Organic synthesis in experimental impact shocks.
abstract: Laboratory simulations of shocks created with a high-energy laser demonstrate that the efficacy of organic production depends on the molecular, not just the elemental composition of the shocked gas. In a methane-rich mixture that simulates a low-temperature equilibrium mixture of cometary material, hydrogen cyanide and acetylene were produced with yields of 5 x 10(17) molecules per joule. Repeated shocking of the methane-rich mixture produced amine groups, suggesting the possible synthesis of amino acids. No organic molecules were produced in a carbon dioxide-rich mixture, which is at odds with thermodynamic equilibrium approaches to shock chemistry and has implications for the modeling of shock-produced organic molecules on early Earth.
authors.affiliation: Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA. mckay@gal.arc.nasa.gov
authors.forename: C P
authors.initials: CP
authors.lastname: McKay
authors.forename: W J
authors.initials: WJ
authors.lastname: Borucki
mesh_terms: D000114:Acetylene / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry; D019418:Evolution, Chemical; D005740:Gases; D006358:Hot Temperature; D006856:Hydrogen Cyanide / Q000737:chemistry*; D007834:Lasers; D019110:Meteoroids; D008697:Methane / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D000588:Amines; D000596:Amino Acids; D005740:Gases; D002245:Carbon Dioxide; D006856:Hydrogen Cyanide; D000114:Acetylene; D008697:Methane