Electrical conductivity and magnetic dynamos in magma oceans of Super-Earths

• DOI: 10.1038/s41467-018-06432-6
• Publication Date: 2018-09-18T13:47:20Z
• Authors: François Soubiran; Burkhard Militzer
• Keywords: [SDU] Sciences of the Universe [physics]; 0301 basic medicine; 03 medical and health sciences; 550; [SDU]Sciences of the Universe [physics]; 13. Climate action; Science; Q; 500; Article

Abstract Super-Earths are extremely common among the numerous exoplanets that have been discovered. The high pressures and temperatures in their interiors likely to lead long-lived magma oceans. If electrical conductivity is sufficiently high, mantles of Super-Earth would generate own magnetic fields. With ab initio simulations, we show upon melting, behavior typical mantle silicates changes from semi-conducting semi-metallic. increases optical properties substantially modified. Melting could thus be detected with high-precision reflectivity measurements during short time scales shock experiments. We estimate order 100 Ω −1 cm , which implies a dynamo process develop oceans if convective velocities values 1 mm/s or higher. predict rotation periods longer than 2 days multipolar