Observations of star-forming regions: the "kitchen" of pre-biotic chemistry

Abstract:

It is now very clear that our Sun, and all stars in the Milky Way and beyond, are born inside dense and cold interstellar clouds. Theory suggests, and observations confirm, that stars and all bodies gravitationally bound to them (including planets) form from the gravitational collapse of these clouds through three main steps: the prestellar phase, the protostellar phase, and the protoplanetary disk phase. The latter phase is then followed by the formation of planets. Simultaneously with the evolution from one phase to the other, the chemical composition gains increasing complexity. In this respect, star-forming regions can be seen as astrochemical "kitchens" where the ingredients, i.e. the atoms of the most abundant elements, are combined to form increasingly complex molecules. Some of those have a biogenic potential, and could have been delivered on the surfaces of nascent planets, contributing to the emergence of life on Earth and elsewhere. Thanks to powerful telescopes, we can now study in detail these kitchens, and derive their physical properties and chemical composition along all the various evolutionary steps. I will describe the main phases of the formation of a Sun-like star, and the main astrochemical processes occurring during them, focusing in particular on what we know and what we still do not know about the formation, survival, and delivery of pre-biotic molecules.

Il seminario si terrà in presenza. Chi fosse interessato a partecipare deve scrive a classi@sns.it entro le 9:30 di Venerdì 4 febbraio 2022.