We present high-resolution Utrecht Echelle Spectrograph spectra of the quasar PHL 957, obtained in order to study the foreground damped Ly-alpha (DLA) galaxy at z = 2.309. Measurements of absorption lines lead to accurate abundance determinations of Fe, S, and N, which complement measurements of Zn, Cr, and Ni already available for this system. We

We have mapped spectrophotometrically the star--forming regions in the center of the nearby SBm galaxy NGC 4214 with the aim of analyzing the spatial distribution of some of its physical properties (density, excitation, emission line intensity, extinction) and their relationship with the distribution and evolutionary state of the stellar population

Comet Hale-Bopp (1995 O1) has been intensely monitored with the 82cm IAC-80 Telescope at Teide Observatory, Tenerife, Spain. Multicolour photometry taken on various nights in mid-August 1995 shows that the inner coma was redder than solar colours, with a power law spectrum of index ~ -3.5, consistent with dust scattering. A large change in the

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We propose a combination of two dynamos for solar and stellar magnetic activity. A strong-field dynamo operating in the overshoot layer at the base of the convection zone generating superequipartition fields concentrated in isolated flux tubes is responsible for cyclic activity (e.g., sunspots), while a turbulent weak-field dynamo in the convection