Origin of Vesta’s volatile-element depletion

Determine whether the depletion of volatile elements in Vesta resulted from high ambient temperatures in the protoplanetary disk or from evaporation from a magma ocean during Vesta’s evolution.

Background

The paper uses Vesta’s volatile-depleted composition as a proxy for the composition of early-formed planetesimals that contributed to the accretion of Earth and Mars. However, the physical process responsible for Vesta’s depletion pattern is unresolved: it could reflect formation in a hot region of the protoplanetary disk, evaporation associated with a magma ocean, or potentially additional effects such as storage of volatile elements in Vesta’s core. The authors adopt a Vesta-like composition phenomenologically while acknowledging that its causal origin remains uncertain.