High-resolution UCLES/AAT spectra are presented for nine B-type supergiants in the SMC, chosen on the basis that they may show varying amounts of nuclear-synthetically processed material mixed to their surface. These spectra have been analysed using a new grid of approximately 12 000 non-LTE line blanketed tlusty model atmospheres to estimate

Este trabajo está orientado a calcular las masas estelares de una muestra de galaxias luminosas compactas azules (LBCGs) a partir de la fotometría en filtros ópticos y del infrarrojo cercano. Se han medido también las masas estelares para muestras de galaxias espirales y elípticas a modo de comparación. Para la determinación de las masas estelares

We present results from 30 nights of observations of the open cluster NGC 7789 with the Wide Field Camera on the Isaac Newton Telescope, La Palma. From ~900 epochs, we obtained light curves and Sloan r'-i' colours for ~33000 stars, with ~2400 stars having better than 1 per cent precision. We expected to detect ~2 transiting hot Jupiter planets if 1

We present photometric and spectroscopic data of the Type II-P supernova (SN II-P) 2003gd, which was discovered in M74 close to the end of its plateau phase. SN 2003gd is the first Type II supernova (SN) to have a directly confirmed red supergiant (RSG) progenitor. We compare SN 2003gd to SN 1999em, a similar SN II-P, and estimate an explosion date

We exploit deep combined observations with Spitzer and Chandra of the Spitzer Wide-Area Infrared Extragalactic Survey (SWIRE) in the ELAIS N1 region to investigate the nature of the faint X-ray and IR sources in common, to identify active galactic nucleus (AGN)/starburst diagnostics, and to study the sources of the X-ray and IR cosmic backgrounds

In order to characterize the low surface brightness component in blue compact dwarf galaxies, we determine their structural parameters for eight objects by fitting a Sérsic law to their B, V, and R light profiles. We restrict the fit to the outer regions, excluding the starburst emission with the help of color and Hα maps. We discuss the problems