Giovedì 2 Maggio 2019, ore 11:00

Osservatorio Astrofisico di Torino, Sala Seminari di Villa Magliola

Exoplanetary atmospheres at high spectral resolution

Dr. David Ehrenreich

Observatoire Astronomique and Department of Astronomy of the Université de Genève

Versoix, Switzerland

Abstract

Observing transits of exoplanets with the Hubble Space Telescope in the ultraviolet has revealed spectacular atmospheric escape of strongly irradiated gas giants. This atmospheric photo-evaporation could explain the dearth of intermediate-mass planets close to their stars, as well as the valley separating two populations of super-Earths. The deposition of a tremendous amount of high-energy irradiation in the outer atmospheric layers of exoplanets should also impact their physical and chemical properties. I will review recent observations obtained wh ground-based, high-resolution spectrographs, that unveil the extreme conditions reigning in the upper atmospheres of exoplanets.