Interstellar Chiral Evolution‒Exploring Enantiomeric Excesses in Evolving Environments

The origin of life is a profound and experimentally challenging question, with an inherent bias for handed molecules at a chemical level.

Homochirality, specifically the preference for left-handed (L-) amino acids in Earth's life, has inspired numerous studies.

Meteorite samples provide evidence that this bias originated long before Earth's formation, tied to water-rich interstellar ices and circularly polarized starlight.

Yet, we still lack a complete understanding of the chiral photon interaction with organic molecules under realistic astrophysical conditions where chiral species are embedded in an amorphous water-rich ice matrix.Intriguingly, amino acids in highly aqueous-altered meteorites show more than 20% enrichment in L enantiomers, indicating hitherto undiscovered asymmetric amplification mechanisms during secondary alteration processes within parent celestial bodies.

While extraerrestrial amino acids have been extensively studied, sugar monomers and aminonitriles are equally important, potentially serving as precursors to amino acids.

Neglecting their chiral bias and the prospects of a possible chirality transfer or mutual chiral amplification mechanisms between amino acids and sugars represents a gap in current research.

The ICE-EEVOLVE project aims to unravel the journey of amorphous ice and chiral organics from molecular clouds to evolved planetary systems, exploring asymmetric chemical evolution influenced by circularly polarized starlight and alteration processes.

This will be achieved through novel laboratory experiments on amorphous interstellar ices processed using synchrotron, laser, and hydrogen lamp sources, combined with enantioselective analyses of pristine extraterrestrial samples.

Our research is guided by the idea that the co-evolutionary history of peptides and nucleic acids in biology is linked to the inherent chirality of their constituent monomers, possibly originating in presolar and Solar System (water-rich) bodies.