Simulations for Terrestrial Planet Formation

TL;DR

This study uses simulations to explore how terrestrial planets form after gas dissipation, considering planetary perturbations, initial conditions, and water transfer mechanisms, revealing formation timescales, accretion rates, and planetary characteristics.

Contribution

It introduces a two-planet model simulation approach to analyze terrestrial planet formation, including water transfer and survival of small planets at resonances.

Findings

Terrestrial planets form within 50 Myr with 60-80% accretion efficiency.

3-4 terrestrial planets typically form inside Jupiter's orbit with varied masses.

Water transfer from outer regions can supply habitable zone planets.

Abstract

We investigate the formation of terrestrial planets in the late stage of planetary formation using two-planet model. At that time, the protostar has formed for about 3 Myr and the gas disk has dissipated. In the model, the perturbations from Jupiter and Saturn are considered. We also consider variations of the mass of outer planet, and the initial eccentricities and inclinations of embryos and planetesimals. Our results show that, terrestrial planets are formed in 50 Myr, and the accretion rate is about 60% - 80%. In each simulation, 3 - 4 terrestrial planets are formed inside "Jupiter" with masses of $0.15 - 3.6 M_{\oplus}$. In the 0.5 - 4AU, when the eccentricities of planetesimals are excited, planetesimals are able to accrete material from wide radial direction. The plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this mechanism. Accretion may also happen a few times between two giant planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of $10^8$ yr.