Host: The Japanese Association of Mineralogists, Petrologists and Economic Geologists
In terms of the origin of life on the Earth, ammonia is a necessary precursor of amino acids. However, the formation of ammonia in the non-reducing atmosphere of the early Earth is problematic. The abiotic reduction of nitrogen in the primitive ocean is a topic of current debate1-3. As shown below, this process is not only possible but highly probable when extraterrestrial objects, containing metallic iron, impact on the primitive ocean. Here we describe the reduction of nitrogen to ammonia by shock experiments with Cu3N, Fe and H2O, and the simultaneous formation of some amino acids from carbon impurities present in the solid reactants. Being water-soluble, these compounds would dissolve in the ejected water, and accumulate in the primitive ocean. By forming a complex with clay minerals, the organic molecules could survive the intense ultra-violet radiation, and be available for further chemical evolution.
