A new martian crater chronology: Implications for Jezero crater

TL;DR

This paper introduces a new martian crater chronology derived from dynamical models, improving age assessments of planetary surfaces like Jezero crater by addressing uncertainties in impact flux evolution.

Contribution

It presents a novel martian crater chronology based on current dynamical models, refining the extrapolation from lunar data and considering impact flux uncertainties.

Findings

New chronology model for Mars impacts

Application to Jezero crater's dark terrain

Analysis of uncertainties in impact flux evolution

Abstract

Crater chronologies are a fundamental tool to assess relative and absolute ages of planetary surfaces when direct radiometric dating is not available. Martian crater chronologies are derived from lunar crater spatial densities on terrains with known radiometric ages, and thus they critically depend on the extrapolation Moon to Mars. This extrapolation requires knowledge of the time evolution of the impact flux, including contributions from various impactor populations, factors that are not trivially connected to the dynamical evolution of the early Solar System. In this paper, we will present a new martian crater chronology based on current dynamical models, and consider the main sources of uncertainties. The new martian crater chronology is discussed using two interesting applications: Jezero crater's dark terrain (relevant to the NASA Mars 2020 mission) and the southern heavily cratered highlands. [abridged]