Reconstructing Meteoritic Organic Compounds in Early Solar System: An Approach from Prebiotic Synthesis in Interstellar and Meteorite Parent Body Environments

Abstract

A gas mixture of carbon monoxide, ammonia, and water was irradiated with high-energy protons to produce an interstellar organic analog (hereinafter abbreviated as CAW), which contains amino acid precursors. Separately, an aqueous solution of formaldehyde, methanol and ammonia (hereinafter abbreviated as FMAW) was subjected to gamma irradiation, both with and without CAW. Free amino acids, CAW, and nucleobases were also gamma-irradiated in aqueous environments. It was suggests that interstellar organic matter imported into asteroids could have played a role in diversifying the organic inventory observed in meteorites. Since meteorites have been exposed to radiation from medium-/long-lived radionuclides for billions years, such post-formation effects must be considered when reconstructing the nature of extraterrestrial organics originally delivered to the early Earth.