Vesta’s surface is dominated by two overlapping impact basins: the older ~400 km Veneneia basin and the younger ~500 km diameter Rheasilvia basin.Their age and nature, along with the ejecta they produced in the form of V-type asteroids, can help us probe Vesta’s evolution.By modeling the production of craters superposed on these basins or on features created by their formation, we predict Veneneia and Rheasilvia basins are 3.2–3.5 Ga and ~1 Ga, respectively. Numerical models indicate they were created by the impact of ~60–70 km projectiles. These impacts likely dredged up material formed at >50 km depths within Vesta. The evidence for the formation time of Veneneia and Rheasilvia in the eucrite and howardite meteorite record exists but is limited. The absence of an obvious spike of 40Ar/39Ar shock degassing ages may be a consequence of low Main Belt impact velocities (< 5 km/s). Most V-type asteroids in the inner main belt are ejecta from one of these two basins. The scattered and limited population of V-types in the central and outer main belt have no clear source. We postulate they are fragments from Vesta-like bodies that originally formed in the terrestrial planet region.

A search for volcanic and plutonic features on Vesta was an important driver for a geomorphological examination of the asteroid. Another goal was to determine if the asteroid was a protoplanet, one of the remnants of the material that formed the Solar System. Therefore, NASA’s Dawn spacecraft collected imaging, spectroscopic, and elemental abundance data, which were utilized to examine the asteroid’s surface. A digital terrain model was created and the asteroid’s various geomorphic features were analyzed. Large scale features include the Rheasilvia and Veneneia impact basins, the Divalia Fossae and Saturnalia Fossae trough sets, and the Vestalia Terra plateau. Small scale features include deposits of dark material, pitted terrain, pit crater chains, mass-wasting deposits, and impact craters. While these geomorphic analyses revealed no evidence of volcanism, evidence of magmatic activity on Vesta was identified. In addition, analysis of Vesta’s geomorphology suggests that it is not only a protoplanet, but also an intermediate body between asteroids and planets.