Spectrum of the exoplanet HR 8799 c. Image credit: ESO/M. Janson

The actual research on star formation in Stockholm focuses on the observational characteristics of planets and discs, both around young and old stars. The group uses adaptive optics instruments to correct for atmospheric distortion and get clearer images of faint discs and planets around bright parent stars, and uses high-resolution spectroscopy to examine their properties. There is also heavy involvement in space-based facilities such as CHEOPS and PLATO, which can detect unresolved planets through the so-called transit method, where a planet passing in front of a star blocks out a small fraction of the star’s light. Additionally, the group develops techniques for so-called astrometric planet detection, where a planet can be detected from its minute gravitational impact on its parent star.

To first approximation, the thin light-emitting surface layer of a star - the stellar atmosphere - preserves the composition of its birth cloud. By collecting high-resolution spectra of large stellar samples of different ages, we can trace the build-up of structure and chemical elements over time in the Milky Way and its satellite galaxies. Accurate inference of stellar parameters however require that the physical model of the atmosphere is correct, calling for non-equilibrium radiative transfer in dynamic and multi-dimensional simulations. Researchers in Stockholm are greatly invested in the spectral analysis efforts of million-star surveys like GALAH, WEAVE, and 4MOST. 

Astrobiology is a cross-disciplinary research area which is trying to understand the conditions for the emergence of life in the Universe. Since the formation and evolution of planets, and complex molecules play an important role for the origin of life, we are also part of the 
Stockholm University Astrobiology Centrum, together with Depts. of Physics, Geological Sciences, and Molecular Biology and Functional Genomics.

 

For contact information, visit the List of staff.