New stars are born when the gaseous material of interstellar nebulae gets concentrated under the rip of gravitational attraction. The process of star formation implies a complete set of violent, specific phenomena that usually happen hidden behind the absorbing nebular material. However, modern observation techniques with infrared light are able to penetrate into those turbulent and dark regions where young stars are born. This way it is possible to study some of the energetic and violent processes involved in star formation…

Stars exist, normally, inside galaxies: huge stellar accumulations containing many thousand millions of members. The Sun itself belongs to one of such systems, normally called the Galaxy. For this reason, from the Solar System we contemplate a night-sky full of stars: we are seeing the closest companions of the Sun inside the Galaxy. But several astrophysical mechanisms are capable of ejecting stars from inside a galaxy directly into the intergalactic space. Those stars, the so-called hyper-velocity stars, reach speeds of hundreds of kilometres per second. Recently, the first hyper-velocity star from an external galaxy has been detected in a research leaded at the Ruhr-University (Bochum, Germany), and Calar Alto telescopes and instruments have played a key rule in this discovery…

Gamma-ray bursts (GRBs) are brief and intense flashes of gamma-ray radiation that occur randomly in any direction of the sky. After some decades of study, these very violent phenomena still give astronomers reasons for surprise. A new type of GRB-related explosion has been discovered recently, and Calar Alto telescopes have played their role in this story…