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Three new grids of stellar evolutionary models with Z=0.01 are presented for the following values of initial hydrogen content X_i_=0.80, 0.73 and 0.63. The latest set of radiative opacities with spin-orbit coupling provided by the Lawrence Livermore group are used. For the lower temperatures the results by Alexander were considered. The models were

We present preliminary results from the ongoing ground-based photometric observing program of the TEP (Transit of Extrasolar Planets) network to detect planets in orbit around eclipsing binary stars. Observing eclipsing binaries overcomes the statistical improbability of planetary transits as the planetary orbital plane may be expected to be

CCD monitoring of Comet Hale-Bopp (1995 O1) has been carried out on more than 50 nights using the 82cm IAC-80 Telescope at Teide Observatory (Tenerife, Spain), operated by the Instituto de Astrofísica de Canarias. A combination of deep exposures of the extended coma in BVRI (up to 2 hours total exposure in a single filter) and near nucleus imaging

We have computed limb-darkening coefficients for five commonly used near infrared photometric bands, namely R, I, J, H, and K, using the stellar atmosphere models by Kurucz (1993). Since the behaviour of the specific intensities is very dependent on the range of effective temperatures considered, we have adopted three analytical approximations to

High resolution spectroscopic observations have been obtained for the ring nebulae around the galactic Wolf-Rayet stars WR 113 (CV Ser), WR 116, WR 128 (MR 95), WR 133, WR 134 (MR 100) and WR 153 using an echelle spectrograph. Gaussian fit analysis of the emission lines has been performed to establish the dynamical classification of the objects as