We present a library of Utrecht echelle spectrograph (UES) observations of a sample of F, G, K and M field dwarf stars covering the spectral range from 4800 Angstroms to 10600 Angstroms with a resolution of 55000. These spectra include some of the spectral lines most widely used as optical and near-infrared indicators of chromospheric activity such

IAUC 6848 available at Central Bureau for Astronomical Telegrams.

Optical Transients from gamma-ray burst sources, in addition to offering a distance determination, convey important information about the physics of the emission mechanism, and perhaps also about the underlying energy source. As the gamma-ray phenomenon is extremely diverse, with timescales spanning several orders of magnitude, some diversity in

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RXJ 2117+3412 is a transition object between the planetary nebulae and the white dwarfs. The central star is a pulsating PG 1159 type star. We summarize here the results of the campaigns organized between 1992 and 1994. We identify about 50 modes, most of them probably belonging to l = 1. The derived mass of the star is 0.57 Msun. Its distance can