[MIS17-11] Formation of organic compounds by hypervelocity impacts on terrestrial planets
Keywords:Origin of life, Early Earth, Meteorite, Mars
We conducted shock-recovery experiments to simulate an impact-induced reaction associated with hypervelocity impacts of Fe-bearing meteorites on ocean with CO2-N2 atmosphere. The typical starting materials contains iron, nickel, forsterite, water, sodium bicarbonate, and gaseous nitrogen. Shock wave was provided by an impact of metal disc plate on a metal container containing the starting materials. The products were analyzed with liquid chromatography mass spectrometry. Powder X-ray diffractometer was used for mineral identification.
The product contained many organic compounds. These yields depend on the compositions of redox state of the minerals in the starting materials. The most reduced mineral mixture provided the highest organic yields. Metallic iron was oxidized to iron carbonate, siderite.
The preset results indicate that ancient impact events formed organic compounds including essential ingredients of life from the major C and N species on prebiotic Earth. This results also suggests that this type of synthesis was happened on Noachian Mars, since major component of atmosphere on Noachian Mars is estimated as oxidized C and N, i.e., CO2 and N2.