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arXiv · 1408.1215

Terrestrial Planet Formation in the Presence of Migrating Super-earths

André Izidoro·Alessandro Morbidelli·Sean N. Raymond
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Abstract

Super-Earths with orbital periods less than 100 days are extremely abundant around Sun-like stars. It is unlikely that these planets formed at their current locations. Rather, they likely formed at large distances from the star and subsequently migrated inward. Here we use N-body simulations to study the effect of super-Earths on the accretion of rocky planets. In our simulations, one or more super-Earths migrates inward through a disk of planetary embryos and planetesimals embedded in a gaseous disk. We tested a wide range of migration speeds and configurations. Fast-migrating super-Earths ($\tau_{mig} \sim$0.01-0.1 Myr) only have a modest effect on the protoplanetary embryos and planetesimals. Sufficient material survives to form rocky, Earth-like planets on orbits exterior to the super-Earths'. In contrast, slowly migrating super-Earths shepherd rocky material interior to their orbits and strongly deplete the terrestrial planet-forming zone. In this situation any Earth-sized planets in the habitable zone are extremely volatile-rich and are therefore probably not Earth-like.

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André Izidoro, Alessandro Morbidelli, Sean N. Raymond. 2014-08-06. Terrestrial Planet Formation in the Presence of Migrating Super-earths. https://doi.org/10.1088/0004-637x/794/1/11

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