[Submitted on 19 Jul 2023]
Abstract: The origin of life on Earth would benefit from a prebiotic atmosphere that
produced nitriles, like HCN, which enable ribonucleotide synthesis. However,
geochemical evidence suggests that Hadean air was relatively oxidizing with
negligible photochemical production of prebiotic molecules. These paradoxes are
resolved by iron-rich asteroid impacts that transiently reduced the entire
atmosphere, allowing nitriles to form in subsequent photochemistry. Here, we
invest
