Astro Seminar: "Exodynamos: Magnetic Field Generation and Detectability"

Wed, 03/30/2016 - 14:00 - 16:00

Planetary magnetic fields are ubiquitous in the Solar System and extrasolar planets are common in the galaxy.  However, no extrasolar planetary magnetic field (or exodynamo) has yet been directly detected. Magnetic fields offer a unique window into the internal structure and dynamics of planets, can be remotely detected by electron cyclotron emission at radio wavelengths, and are commonly assumed to be important for surface habitability.  In this talk we describe the conditions necessary for the generation of magnetic fields in the cores of terrestrial exoplanets, how they might evolve over time, and the important role of internal heat sources. We demonstrate that eccentric Earth-mass planets in the habitable zone around M dwarfs are likely to be within the “tidal zone”, where gravitational tidal dissipation can be extreme, prolonging the magma ocean phase and inhibiting dynamo action.  

David Rittenhouse Laboratory, A4