Chuanfei Dong, Princeton University
May 4, 2021 at 3:00 pm (PDT)

“Star-Terrestrial Planet Interactions in Our Solar System and Beyond: Magnetic Fields, Atmospheric Loss, and Habitability”

Research in exoplanets now encompasses a wide spectrum of fields ranging from astrophysics to heliophysics and climate science. One of the primary objectives of studying exoplanets is to determine the criteria for habitability, and whether certain exoplanets meet these requirements. The classical definition of the Habitable Zone (HZ) is the region around a star where a planetary surface can support liquid water, but this definition largely ignores the impact of the stellar wind and stellar magnetic activity on the erosion of an exoplanet’s atmosphere. Amongst the many factors that determine habitability, understanding the atmospheric loss is of paramount importance. In this presentation, I will begin with different atmospheric loss mechanisms and use Mars as an example to delineate different escape processes. To study Martian atmospheric losses over time, a sophisticated whole atmospheric model and an exospheric Monte Carlo model are coupled with a magnetohydrodynamic (MHD) code to simulate the whole Martian system from the surface to interplanetary space. By adopting a similar modeling approach, I will also discuss the impact of exoplanetary space weather (i.e., stellar winds and stellar magnetic activity) on exoplanets’ atmospheric losses, which offers fresh insights into potentially habitable exoplanets orbiting M-dwarfs. Finally, I will use Mercury as an example to illustrate how planetary interior-magnetosphere coupling could have changed star-planet interaction processes.
Due to the ongoing global COVID-19 pandemic, all presentations this quarter will only be presented remotely via Zoom. There will be no in-person presentation or reception at the University of Washington Seattle Campus!

In keeping with recommended best practices, all presentations will be password protected. To access the meeting please email in advance to request the code.