Size-effect on the formation of magnetic field for silicate planet

Abstract

Habitability of solid planets have been discussed mainly related to the distance from the central star, the size of the planet, and the obliquity of rotation axis. In addition to that the planet should be shielded from high-energy irradiation from the central star to cultivate lives on the surface of the planet. If the planet had intrinsic magnetic field, the surface would be saved from the high-energy irradiation as is the case for present Earth. Then the question is what is the condition to be satisfied to have intrinsic magnetic field.In this study we carried out numerical model on the thermal evolution of terrestrial planets with various sizes to discuss the condition to be satisfied to form intrinsic magnetic field.