We have obtained HST WFPC2 and NICMOS observations in the nuclear region of the closest powerful active galaxy known, NGC 5128 (Centaurus A). Narrow band imaging in the Paalpha line shows an elongated structure around the nucleus which we interpret as a disk of ionized gas, with a 15 pc radius. The disk does not appear to be perpendicular to the

The Howardite-Eucrite-Diogenite (HED) suite is a family of differentiated meteorites that provide a unique opportunity to study the differentiation of small bodies. The likely parent-body of this meteorite group, (4) Vesta is presently under study by the Dawn mission, scrutinizing its surface in the visible and NIR infrared range. Here, we discuss

Nitrogen lines of the N I lambda1134 and lambda1200 multiplets in the damped Lyalpha (DLA) galaxies at z_abs = 2.309, 2.827, and 3.025 toward the QSOs 0100+1300, 1425+6039, and 0347-3819, respectively, have been detected by means of high-resolution spectra (R ~ 2 x 10^4) obtained with 4 m class telescopes at ESO (La Silla, Chile) and the

We investigated the reliability of our silicon atomic model and the influence of non-local thermodynamical equilibrium (NLTE) on the formation of neutral silicon (Si i) lines in the near-infrared (near-IR) H-band. We derived the differential Si abundances for 13 sample stars with high-resolution H-band spectra from the Apache Point Observatory

The early-type galaxy (ETG) mass-size relation has largely been studied to understand how these galaxies assembled their mass. One key observational result of the last years is that massive galaxies increased their size by a factor of a few at fixed stellar mass from z ~ 2. Hierarchical models favor minor mergers as a plausible driver of this size

We present high-resolution, time-resolved optical spectroscopy of the black hole X-ray transient Swift J1753.5-0127. Our optical spectra do not show features that we can associate with the companion star. However we do observe broad, double-peaked emission lines, typical of an accretion disc. We show that the mass of the compact object is likely >7