Seminar: Stability and Evolution of Secondary Atmospheres and its Importance for Planetary Habitability
The stability and evolution of secondary atmospheres is governed by various important geophysical, aeronomical, astrophysical, and potentially even biological, processes. From an aeronomical viewpoint, a planet's interaction with its host star's plasma and radiation environment, atmospheric composition, and planetary mass can be considered to be the main drivers that shape the long-term evolution of secondary atmospheres. A comparative view on Earth and Mars (and Venus) illustrates the importance of each of these factors and can also give important insights into the evolution of planetary habitability. Within this presentation, I will therefore briefly discuss such aeronomical/astrophysical parameters mostly exemplified through the diverging paths that were taken by Earth and Mars. These two planet's not only illustrate the importance of atmospheric stability and evolution for planetary habitability in the Solar System and beyond, they also reveal further parameters that will be crucial for Earth-like atmospheres to emerge; one of which may even be the origin of life itself. I will touch on some of these parameters and discuss what we may learn from atmospheric evolution in the Solar System about habitability within the Galaxy.