We analyze images of BL Lacertae objects obtained with the Hubble Space Telescope WFPC2 and the F814W filter. The nine objects cover a redshift range of 0.19 to...

Studies of globular cluster systems play a critical role in our understanding of galaxy formation. Imaging with the Hubble Space Telescope has revealed that...

We review our current understanding of the internal dynamical properties of the dwarf spheroidal galaxies surrounding the Milky Way. These are the most dark...

The study of the stellar content and physics of the ionized gas in local high-mass star-forming regions is specially important for better understanding...

Daily measurements of the solar aureole were made at the Vacuum Newton Telescope (/D=40 cm) at the Teide Observatory (Tenerife) for various airmasses. We use...

We present the modelling of new indicators for old and intermediate age stellar populations based on the absorption features of Mg λ ˜ 5175 Å, Fe λ ˜ 4383 Å...

We present results of our ongoing study of the morphology and kinematics of the ionised gas in 48 representative nearby elliptical and lenticular galaxies using...

Over the last 40 years, X-ray astronomy missions have revealed long-term, superorbital periods in a variety of X-ray binaries. These modulations can provide...

By detecting ionised-gas emission in 75% of the cases, the SAURON integral-field spectroscopic survey has further demonstrated that early-type galaxies often...