Planetary Evaporation

Abstract

Evaporation of magma oceans exposed to space may have played a role in the chemical and isotopic compositions of rocky planets in our Solar System (e.g., Earth, Moon, Mars) and their protoplanetary antecedents. Chemical depletion of moderately volatile elements and the enrichment of these elements’ heavier isotopes in the Moon and Vesta relative to chondrites are clear examples. Evaporation is also thought to be an important process in some exoplanetary systems. Identification of evaporation signatures among the rock-forming elements could elucidate important reactions between melts and vapors during planet formation in general, but the process is more complicated than is often assumed.