Long slit spectrophotometry of 13 bipolar planetary nebulae has been used to study their physical and chemical properties. In each nebula, one to seven different spatial regions have been considered in order to search for possible abundance variations through the nebulae. We obtained the following main results: - within the errors, the He, O, and N

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The best studied gravitational lens is the Twin QSO Q0957+561, and as a result of recent advances in observations and modelling, a ten percent measurement of the Hubble constant is attainable. We discuss in detail this system and review the perspectives in a near future.

The tables list positions, sizes and photometry in V and R band of extended objects found in fields, which include a nearby interacting galaxy. The tables' filenames are a combination of the table number and the interacting galaxy's name. The column-descriptions of all tables are identical, expect that the positional offsets refer to different

IAUC 6816 available at Central Bureau for Astronomical Telegrams.

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