Building Terrestrial Planets

TL;DR

This paper reviews current models and simulations of terrestrial planet formation, emphasizing the influence of giant planets and geochemical constraints to understand the early Solar System and planetary diversity.

Contribution

It combines dynamical simulations with geochemical data to provide a comprehensive scenario of terrestrial planet formation and evolution, highlighting the role of giant planets.

Findings

Terrestrial planet accretion depends on giant planet architecture.

Mars and Earth have different accretion timescales and masses.

Water and volatiles likely originate from specific accretion processes.

Abstract

This paper reviews our current understanding of terrestrial planets formation. The focus is on computer simulations of the dynamical aspects of the accretion process. Throughout the chapter, we combine the results of these theoretical models with geochemical, cosmochemical and chronological constraints, in order to outline a comprehensive scenario of the early evolution of our Solar System. Given that the giant planets formed first in the protoplanetary disk, we stress the sensitive dependence of the terrestrial planet accretion process on the orbital architecture of the giant planets and on their evolution. This suggests a great diversity among the terrestrial planets populations in extrasolar systems. Issues such as the cause for the different masses and accretion timescales between Mars and the Earth and the origin of water (and other volatiles) on our planet are discussed at depth.