# Terrestrial planet formation: Dynamical shake-up and the low mass of Mars

## TL;DR

This paper presents a dynamical shake-up model where a sweeping secular resonance caused by Jupiter's influence during solar nebula depletion explains the small mass of Mars and the absence of planets in the asteroid belt, supported by numerical simulations.

## Contribution

It introduces a new dynamical model linking resonance sweeping to terrestrial planet formation and asteroid belt characteristics, supported by extensive numerical calculations.

## Key findings

- Resonance sweeping inhibits planet formation in the asteroid belt.
- The model explains the low mass of Mars.
- Asteroid belt analogs may be common around other stars.

## Abstract

We consider a dynamical shake-up model to explain the low mass of Mars and the lack of planets in the asteroid belt. In our scenario, a secular resonance with Jupiter sweeps through the inner solar system as the solar nebula depletes, pitting resonant excitation against collisional damping in the Sun's protoplanetary disk. We report the outcome of extensive numerical calculations of planet formation from planetesimals in the terrestrial zone, with and without dynamical shake-up. If the Sun's gas disk within the terrestrial zone depletes in roughly a million years, then the sweeping resonance inhibits planet formation in the asteroid belt and substantially limits the size of Mars. This phenomenon likely occurs around other stars with long-period massive planets, suggesting that asteroid belt analogs are common.