The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and

As a high-resolution, near-infrared, fiber-fed instrument, APOGEE presents a unique opportunity to obtain multi-epoch radial velocity measurements of a large number of low-mass stars. These observations will reveal unseen companions, improving our understanding of stellar multiplicity at the bottom of the Main Sequence, and may even identify

One of the continuing challenges facing astronomers today is the need to obtain ever higher resolution images of the sky. Whether studying nearby crowded fields or distant objects, with increased resolution comes the ability to probe systems in more detail and advance our understanding of the Universe. Obtaining these high-resolution images at

The history of the Milky Way is recorded in its stars, but dissecting stellar populations is not a straighforward process. Key information is gained by analyzing the absorption lines from high-resolution spectroscopy of stellar atmospheres by the APOGEE survey and analyzing the frequencies in power spectra of photometric lightcurves by Kepler

We present the characterization of the three T type candidates (S Ori 70, S Ori 73, and S Ori J053804.65-021352.5) lying in the line of sight towards σ Orionis (˜3 Myr, ˜352 pc, solar metallicity) by means of near-infrared photometric, astrometric, and spectroscopic studies. H-band methane images were collected for all three sources using the LIRIS

We use the statistics of caustic crossings induced by microlensing in the lens system Q 2237+0305 to study the lens galaxy peculiar velocity. We calculate the caustic crossing rates for a comprehensive family of stellar mass functions and find a dependence of the average number of caustic crossings with the effective transverse velocity and the