Fluorescent X-rays from the surfaces of airless planetary bodies in the inner solar system have been measured by instruments on several spacecraft. X-ray emission follows photoionisation by incident solar X-rays and charged particles and reveals the elemental composition of the surface. Analyses of X-ray spectra obtained by orbiting spacecraft, use

The low-frequency peaked BL Lac (LBL) object BL Lacertae was observed with the MAGIC telescope from August to December 2005 (22.2 hrs), and from July to September 2006 (26.0 hrs). A very high energy (VHE) gamma-ray signal was discovered with a 5.1 sigma excess in the 2005 data. Above 200 GeV, an integral flux of approximate by 3% of the Crab flux

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