Is Vesta a Protoplanet?
Vesta’s overall bulk density, inferred core, and olivine-free basaltic achondrite crust, as determined by the recent Dawn mission, cannot be explained by simply differentiating a chondritic protoplanet: Vesta's overall density is too low, and its core and crust too big, to fit anything like cosmic abundances of major or trace elements. Instead, we will explore more exotic theories of Vestan formation and evolution in a violent early solar nebula.
Br. Guy Consolmagno, SJ (Vatican Observatory)