High-velocity clouds (HVCs) are a part and parcel among gaseous material that falls onto the Milky Way and other galaxies. They show up with a too high velocity to be consistent with a simple model of galactic differential rotation. They are a quite common phenomenon and are observed in the entire electromagnetic spectrum in absorption and emission. However, since their discovery in 1963 by Muller et al. the distances of only a sparse fraction could be determined. Indeed, the metal abundances are well known and emission line studies revealed a rather sub-solar metallicity (on average Z~0.3Z_☉).

The origin of HVCs is still a matter of debate. The studies of Sylvia (see also her website) focus on the different evolutions of HVCs being on the one hand dominated by and on the other hand lack of dark matter. These investigations may help to figure out a particular formation scenario.

The possibilty of star formation in HVCs is another interesting research topic. Despite the physical boundary conditions would definitely allow for star formation it has never been found any stellar component being assigned with them. The analyses of Bastian (cf. his website) try to shed light on that mystery.

This project aims at comprising both observations and simulations of high-velocity clouds. We jointly do our investigations with Prof. Jürgen Kerp and Dr. Nadya Ben Bekhti (Argelander-Institut für Astronomie), and Dr. Benjamin Winkel (Max-Planck-Institut für Radioastronomie).