We present a detailed study of the star formation history (SFH) of the Tucana dwarf spheroidal galaxy. High-quality, deep HST/ACS data, collected in the framework of the LCID project, allowed us to obtain the deepest color-magnitude diagram to date, reaching the old main-sequence turnoff (F814 ~ 29) with good photometric accuracy. Our analysis

We will present preliminary results of the occultation of Tycho star 6833-00163-1 by the dwarf-planet 1 Ceres. The 11.8 visual magnitude star was occulted in the night of 17 August 2010, with the shadow passing through south, south-east and central part of Brazil. The observation was a challenge because of the drop in magnitude was only 0.07 for a

We report a Swift follow-up observation of the very faint X-ray transient source XTE J1728-295 (also IGR J17285-2922, ATel #2825) currently in the decaying phase of its recent outburst (ATel #2823, #2824, #2869). The observation was performed on 2010-10-29 07:07:35 UTC for a duration of 2 ks, and was observed in Photon Counting (PC) mode

IBIS-ISGRI observations on 2010-10-10 (Bordas et al. ATel #2919) as well as RXTE-PCA scans on 2010-10-09 (http://lheawww.gsfc.nasa.gov/users/craigm/galscan/html/EXO_1745-248.html) showed enhanced X-ray emission from the direction of the globular cluster Terzan 5. We analysed a ~500 s Swift-XRT observation of the field starting on 2010-10-10 01:32

At high-z the most superdense massive galaxies are supposed to be the result of gas-rich mergers resulting in compact remnant. After this, dry mergers are expected to be the mechanism that moves these very massive galaxies towards the current stellar mass size relation. Within these merging scenarios, a non-negligible fraction (1-10%) of these

Context. Knowledge of the intrinsic shapes of galaxy components provides crucial information when constraining phenomena driving their formation and evolution. Aims: We analize the structural parameters of a magnitude-limited sample of 148 unbarred S0-Sb galaxies to derive the intrinsic shape of their bulges. Methods: We developed a new method to