Context: About 500 new variable stars enter the General Catalogue of Variable Stars (GCVS) every year. Most of them however lack spectroscopic observations, which remains critical for a correct assignement of the variability type and for the understanding of the object. Aims: The Variable Star One-shot Project (VSOP) is aimed at (1) providing the

Stellar variability types are assigned on the basis of lightcurve appearance, which often remains unchallenged without further observational evidence. VSOP (Variable Star One-shot Project) is a large international collaboration, which has so far obtained spectra of more than 400 stars during the past year. Operationally this program is a completely

We report on the results from the observations in the very high energy band (VHE; Eγ>=100 GeV) of the black hole X-ray binary (BHXB) Cygnus X-1. The observations were performed with the MAGIC telescope, for a total of 40 hr during 26 nights, spanning the period between 2006 June and November. Searches for steady γ-ray signals yielded no positive

SW Sextantis stars are a relatively large group of cataclysmic variables (CVs) whose properties contradict all predictions made by the current CV evolution theories. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow

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