E-mail: boss@dtm.​ciw.​edu Gas-Phase Prebiotic Chemistry in the Solar System: How and Where Nadia Balucani Dipartimento di Chimica, Università degli Studi di Perugia, Citarinostat Perugia, Italy In the sequence of steps which are believed to have led from elementary particles to the emergence of life, an important one is certainly the formation of simple prebiotic molecules from parent species abundant in the Universe. The aggregation of H, O, N, C (and other element) atoms into molecules and the subsequent chemical evolution are occurring also

now in the Universe, as witnessed by the identification of more than one hundred molecules in the interstellar medium (encompassing also prebiotic

molecules such as glycolaldehyde, formamide and, tentatively, glycine) and by the gas-phase chemical evolution of the atmospheres of several solar objects like Titan. Simple as they might seem compared Emricasan clinical trial to other processes of relevance in astrobiology, the formation mechanisms of many of the observed gaseous prebiotic molecules and radicals are far from being understood. In this contribution, the focus will be on the gas-phase chemical evolution of planetary atmospheres and cometary comae, the

gaseous environments of our Solar System where gaseous organic molecules have been observed. Similarly to the atmosphere of Earth, the atmospheres of the other planets PRKD3 (or satellites, like Titan) can be described as giant Androgen Receptor pathway Antagonists photo-reactors, where the energy deposited mainly by solar photons, but also by cosmic rays and other energetic particles, drives a complex gas-phase chemistry. In this specific context, gas-phase neutral–neutral reactions are expected to play a dominant role. A thorough characterization of the chemical evolution of planetary atmospheres relies on a multi-disciplinary approach: (1) observations allow us to identify the molecules and their number densities as they are nowadays; (2) the chemistry which lies behind their formation starting from atoms and simple molecules is accounted for by complex reaction networks; (3) for a realistic modeling of such networks, a number of experimental parameters are needed and, therefore, the relevant molecular processes should be fully characterized in laboratory experiments.