Interior structure models of terrestrial exoplanets and application to CoRoT-7b

Abstract

In this study, we model the internal structure of CoRoT-7b as a type example for a terrestrial extrasolar planet using mass and energy balance constraints. Our results suggest that the deep interior is predominantly composed of dry silicate rock, similar to the Earth’s Moon. A central iron core, if present, would be relatively small and less massive (< 15 wt.% of the planet’s total mass) as compared to the Earth’s (core mass fraction 32.6 wt.%). Furthermore, a partly molten near-surface magma ocean could be maintained, provided surface temperatures were sufficiently high and the rock component was mainly composed of Earth-like mineral phase assemblages.