New results show how collisions between comets and planets can make molecules that are the essential building blocks of life. This suggests that the chemistry needed to gather the molecular ingredients for life could be more common than previously recognised. Experiments were carried out to mimic comet impacts on early Earth.
They found chemical reactions to make the primordial "soup for life" can occur anywhere that comets collide. Presenting their work at the Goldschmidt conference of geochemists in Prague, Dr Haruna Sugahara and Dr Koicha Mimura reported that after mixtures of ice, amino acids and rock were impacted with a projectile, the amino acids joined up to make complex organic molecules, peptides, which are important building blocks in biochemistry.
Reactions to make peptides could, therefore, occur widely on bodies across the Solar System, including places like comets, as well as around other stars across the Universe, it seems. Prof Mark Burchell, from the University of Kent, UK, who was not involved in the work, commented to BBC News: "What this new work does is to show that if a comet containing such material were to hit a planet, the energy from the impact will drive further chemistry to help form short peptides, chains of amino acids that are useful to make proteins"