  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]
