RSAA Colloquia / Seminars / Feast-of-Facts: Wednesday, 28 November 2018, 11:00-11:20; CSO Common Room

Sarah McIntyre

"Planetary Magnetism as a Parameter in Exoplanet Habitability"

Evidence from the solar system suggests that, unlike Venus and Mars, the presence of a strong magnetic dipole moment on Earth has helped maintain liquid water on its surface. Therefore, planetary magnetism could have a signi ficant effect on the long-term maintenance of atmosphere and liquid water on rocky exoplanets. We use Olson & Christensen’s (2006) model to estimate magnetic dipole moments of rocky exoplanets with radii Rp < 1.23 R+. Even when modelling maximum magnetic dipole moments, only Kepler-186 f has a magnetic dipole moment larger than the Earth’s, while approximately half of rocky exoplanets detected in the circumstellar habitable zone have a negligible magnetic dipole moment. This suggests that planetary magnetism is an important factor when prioritizing observations of potentially habitable planets.