The formation and evolution of molecular complexity in ices is impacted by energetic processing related to cosmic rays and radiation associated with the transition from dense molecular clouds to protoplanetary disks surrounding young stars. Specifically, regarding the evolution of the molecular building blocks of life under energetic processing (Target-6) such processing may on the one hand result in destruction of the molecular building blocks of life, and on the other hand result in the formation of even more complex molecular species, e.g., peptide chains. Also, energetic processing with circularly polarized light of molecular ices containing chiral molecules such as amino acids and sugars may induce enantiomeric excess and provide a possible interstellar pathway to the chiral selectivity that governs amino acids and sugars in terrestrial life today. Circularly polarized light has been observed at IR wavelengths and is predicted by models for UV wavelengths over large areas (covering entire star and planet forming regions) in interstellar molecular clouds due to light scattering from aligned anisotropic dust grains, e.g., in the Orion Nebula. Thus, the observed enantiomeric
excesses in the molecular building blocks of life in some meteoritic samples may indicate a possible interstellar origin for these molecules. We will have unique possibilities to investigate such circularly polarized light induced enantiomeric excesses via development of the unique AU Chiralice setup that will allow for processing of low temperature interstellar ice and dust grain analogues with circularly polarized light, combined with in situ dichroism spectroscopy measurements, to explore pathways to chiral selectivity in amino acids and sugars in the low temperature solid phase under molecular cloud and protoplanetary disk conditions.
Work Package 3.1: Importance of radiation for ice processes
Work Package 3.2: UV-processing pathways to chirality in interstellar molecular building blocks of life
