Constraining the cratering chronology of Vesta

• Published in: Planetary and space science 2014-11, Vol.103, p.131-142
• Main Authors: O׳Brien, David P., Marchi, Simone, Morbidelli, Alessandro, Bottke, William F., Schenk, Paul M., Russell, Christopher T., Raymond, Carol A.
• Format: Article
• Language: English
• Subjects: Age; Asteroids; Chronology; Constraining; Counting; Craters; Diogenites; Impact Chronology; Impact Cratering; Mathematical models; Vesta; Vesta asteroid
• ISSN: 0032-0633; 1873-5088
• DOI: 10.1016/j.pss.2014.05.013

Vesta has a complex cratering history, with ancient terrains as well as recent large impacts that have led to regional resurfacing. Crater counts can help constrain the relative ages of different units on Vesta׳s surface, but converting those crater counts to absolute ages requires a chronology function. We present a cratering chronology based on the best current models for the dynamical evolution of asteroid belt, and calibrate it to Vesta using the record of large craters on its surface. While uncertainties remain, our chronology function is broadly consistent with an ancient surface of Vesta as well as other constraints such as the bombardment history of the rest of the inner Solar System and the Ar–Ar age distribution of howardite, eucrite and diogenite (HED) meteorites from Vesta. •We develop a crater chronology for Vesta based on models of asteroid belt evolution.•Our chronology is consistent with numerous constraints from Vesta.•Application to other large asteroids like Ceres will allow for testing and refinement.