SO-IAA Colloquium: Recent advances about the exoplanetary exospheres

The upper atmosphere of a planet plays a key role at protecting the lower altitudes from the effects of energetic stellar EUV and soft X-ray photons and keV-energy precipitating particles. Through a variety of transport processes, the upper atmosphere also participates in the net loss of a planet’s bulk composition into space. As such, the physics and chemistry occurring in the upper atmosphere influence the evolution of a planet over its lifetime. Understanding these processes is critical to form a complete picture of planet evolution and their response to the stellar environment. Exoplanets represent a unique opportunity to advance our understanding of upper atmospheres because of the diversity of conditions they are exposed to. In this seminar, I will give an overview on recent advances in the investigation of the upper atmospheres of exoplanets, both observational and theoretical.