A method that is widely used to analyse stellar populations in galaxies is to apply the theoretically derived responses of stellar spectra and line indices to element abundance variations, which are hereafter referred to as response functions. These are applied in a differential way, to base models, in order to generate spectra or indices with

TeV gamma-ray signals from the Crab Nebula and Mkn 501 were detected with the HEGRA CT1 imaging Cerenkov telescope during periods when the moon was shining and during twilight. This was accomplished by lowering the high voltage supply of the photomultipliers in fixed steps up to 13%. No other adjustments were made and no filters were used. Laser

Context: .The Isaac Newton Telescope Photometric Hα Survey (IPHAS) is currently mapping the Northern Galactic plane reaching to r'=20 mag with typically 1primeprime resolution. Hundreds of Planetary Nebulae (PNe), both point-like and resolved, are expected to be discovered. We report on the discovery of the first new PN from this survey: it is an

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 present deep near-infrared J, {K}{{s}} photometry of the old, metal-poor Galactic globular cluster M15 obtained with images collected with the LUCI1 and PISCES cameras available at the Large Binocular Telescope (LBT). We show how the use of First Light Adaptive Optics (FLAO) system coupled with the PISCES camera allows us to improve the limiting

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