Supernovae and the chirality of the amino acids

A mechanism for creating amino acid enantiomerism that always selects the same large-scale chirality is identified, and subsequent chemical replication and galactic mixing that would populate the Galaxy with the predominant species is described. This involves (1) the spin of the ¹⁴N in the amino acids, or in precursor molecules from which amino acids might be formed, that couples to the chirality of the molecules; (2) the neutrinos emitted from the supernova, together with the magnetic field from the nascent neutron star or black hole formed from the supernova, which selectively destroy one orientation of the ¹⁴N and thus select the chirality associated with the other ¹⁴N orientation; (3) chemical evolution, by which the molecules replicate and evolve to more complex forms of a single chirality on a relatively short timescale; and (4) galactic mixing on a longer timescale that mixes the selected molecules throughout the Galaxy.