Constraining the Cratering Chronology of Vesta

TL;DR

This paper develops a cratering chronology for Vesta by calibrating crater counts with dynamical models and meteorite ages, aiding in understanding Vesta's surface history.

Contribution

It introduces a new cratering chronology function for Vesta based on current dynamical models and meteorite data, improving age estimations.

Findings

Chronology function aligns with Vesta's ancient surface

Consistent with inner Solar System bombardment history

Supported by HED meteorite age data

Abstract

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.