Project description

Exoplanet search programs have found by now rocky exoplanets around solar-type stars, but also a large population of them around low mass stars; these are the most abundant stars in our galaxy and thus of prime interest also for finding extraterrestrial life. Once rocky planets emerge from the magma ocean stage and solidify, the water and carbon cycles are crucial in controlling the long-term thermal evolution of a planet and its climate. Water plays a crucial role through controlling the mantle viscosity and hence plate speed, the run-away greenhouse effect and the ice-albedo feedback. All of these affect the extent of the Habitable Zone on long timescales.

The PhD project will implement the water cycle into an existing planet evolution model with a long-term carbon cycle. The goal is to quantify how the inner and outer edge of the HZ change over time for a large range of rocky exoplanets (mass, radii, using Earth-like compositions) around stars of various masses (M dwarfs to solar-type stars). In a second step, the interior model will be expanded to enable studying a variable bulk composition. Using recent results from chemical simulations and observations of planet forming disks, the HZ extent and its evolution will be studied for rocky planets that can differ substantially from our own Earth. The results will provide important information for upcoming future missions like LIFE and HWO, which aim to characterize rocky planets and their habitability.

Additional specifications

We look for a candidate with an MSc degree in Astronomy, Physics, or Planetary Science. Familiarity with (exo)planetary interiors and evolution as well as programming skills are an asset, but not a requirement.