We present new CCD narrowband images and spatially resolved intermediate-dispersion spectroscopy of the hydrogen-poor nebulae A30 and A58. These data have allowed us to obtain information on the physical properties and chemical abundances of the inner knots and outer envelopes of A30 and A58 as a basis for the discussion of their implications in

Most previous work studying the possible relation between the presence of non-axisymmetric structures such as bars and rings in a galaxy, and the presence of activity in their nuclei, has been hampered by imperfections in the selection of sample galaxies, and especially of a control sample of non-active galaxies. We have started to tackle this

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We present results of photometry and photopolarimetry of the Wolf-Rayet eclipsing binary system HD 5980 in the Small Magellanic Cloud, which underwent an unexpected eruption during 1994, transforming its spectrum into a Luminous Blue Variable-like one. CCD photometry was performed during the post-outburst declining phase. Pre-outburst

We present results from a two year intensive monitoring of BL Lac object 3C 66A (PKS 0219+428). This object was observed in outburst during these two years. It reached the brightest ever observed magnitude on V=13.59 (1.2.1995) and on K=10.59 (15.2.1994). The optical and infrared light curves are characterised by randomly distributed fast flares

We have obtained spectra with the 10-m Keck telescope of a sample of 24 galaxies having colors consistent with star-forming galaxies at redshifts 2 ≲ z ≲ 4.5 in the Hubble Deep Field (HDF). Eleven of these galaxies are confirmed to be at high redshift (zmed=3.0). The spectra of the confirmed high-redshift galaxies show a diversity of features