The MAGIC telescope has observed very high energy gamma-ray emission from the BL Lac object PG 1553+113 in 2005 and 2006 at an overall significance is 8.8 sigma in 18.8h. The light curve shows no significant flux variations on a daily time-scale. The flux level during 2005 was, however, significantly higher compared to 2006. The differential energy

We review the state of the art of the derivation of star formation histories from color-magnitude diagrams reaching the oldest main sequence turnoffs. From the observational point of view, high quality CMDs are being obtained for galaxies over virtually the whole Local Group. However, the retrieval of star formation histories from these data using

We present wide-field ground based photometry for the Galactic globular cluster M92. Data were collected in the SDSS bands (u',g',r',i',z') with the MegaCam@CFHT. We confirm the occurrence of cluster stars beyond the tidal radius. Moreover, we find that the ratio between the Horizontal Branch (HB) stars and Main Sequence (MS) stars across the turn

Balloon 090100001 has turned out to be one of the most interesting pulsating sdB stars. However, its interest compares with the difficulty for it to be modelled. We present some clues or strategies from which some information can be inferred based on a comparison between observed and theoretical frequencies alone. These strategies might be applied

For a long time, radio-loud Broad Absorption Line Quasars (BAL QSOs) were thought to be extremely rare objects. The absorbing troughs seen in their optical spectra are due to strong winds which probably have their origin within the inner region of the AGN, as a result of the accretion processes. Their radio emission constitutes an additional

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