The stellar group's research topics include the evolution of single and binary stars, nucleosynthesis, stellar population, supernovae and gamma-ray bursts, and stellar and circumstellar (magneto)hydrodynamics. Below gives some ideas on what our members have been involved with.

BOB: B-Fields in OB Stars Massive stars are key agents in the Universe, driving the evolution of star forming galaxies through their photons, winds and violent deaths at all redshifts. The BOB survey collects and studies spectropolarimetric observations for a large number of massive, early-type stars in order to study the oc-
currence rate, properties, and ultimately the origin of magnetic elds in massive stars

VLT-FLAMES Tarantula Survey This is an international collaboration studying about 900 massive stars in the LMC cluster 30 Doradus. The survey tries to answer questions such as the effects of stellar rotation and binarity on the evolution of stars, the binary fraction of massive stars, as well as studying the gas and stellar dynamics  to provide input for models of star and cluster formation.

VFTS 682 is a very bright and massive star in the neighbourhood of the Tarantula nebula, a possible 'runaway star'. The star's apparent isolation is exceptional, because very massive stars are usually found only in dense star cluster environments.

ISM Project Our group is interested not just in stars themselves, but also in how they affect their surroundings. The Inter-Stellar Matter project investigates the feedback effects of winds and radiation from massive stars on the interstellar medium. We also model the effects of stellar explosions (supernovae) at the end of their lives.

Above: Bow shock of a red supergiant star with an initial mass of 20Mo and moving at 20, 40 and 70 km/s as resulted from two-dimensional axisymmetric hydrodynamical simulations (Meyer et al., 2014, Monthly Notices of the RAS, 444, 2754)

Left: Spectroscopic Herzprung-Russel Diagram (sHRD) indicates a star's evolutionary history independent of distance and extinction measurements. Grey scale represents the probability density distribution of the location of 575 Galactic stars in the sHRD (Castro et al., 2014, A&A 57, L13)