Extraterrestrial organic matter: a review.

摘要: We review the nature of widespread organic material present in Milky Way Galaxy and Solar System. Attention is given to links between these environments primitive System objects early Earth, indicating preservation as an interstellar cloud collapsed form Earth accreted such from asteroids, comets interplanetary dust particles. In medium more than 100 molecular species, bulk them organic, have been securely identified, primarily through spectroscopy at highest radio frequencies. There considerable evidence for significantly heavier molecules, particularly polycyclic aromatics, although precise identification individual species has not yet obtained. The so-called diffuse bands are probably important this context. low temperature kinetics clouds leads very large isotopic fractionation, hydrogen, signature components preserved carbonaceous chondritic meteorites. Outer belt asteroids probable parent bodies chondrites, which may contain much 5% material, including a rich variety amino acids, purines, pyrimidines, other potential prebiotic interest. Richer volatiles hence less thermally processed comets, whose matter abundant poorly characterized. Cometary volatiles, observed after sublimation into coma, include many also medium. that most Earth's supplied by 'late' bombardment meteorites, scattered inner following formation giant planets. How way intact molecules interest survived delivery become increasingly debated topic over last several years. principal source organics was accretion particles cometary origin.