Spatially resolved long-slit spectrophotometric data for the planetary nebulae PB 6, NGC 2452, NGC 2867, NGC 6905 and He 2-55 are presented. Different knots were observed in each nebula. All the nebulae are ionized by [WC 2-3] type nuclei. For the five objects, we calculated photoionization models using the ionizing radiation field from models of

It is foreseen that the Gran Telescopio Canarias will include an Adaptive Optics (AO) system to provide diffraction-limited images in the near-IR. The preliminary scientific requirements are presented here and are used to determine the basic system specifications. The sky coverage is determined for the cases of natural and laser guide stars. The

We present a new technique for performing two-dimensional (integral-field) spectroscopy of objects with a large range in intensity. It is based on the capability of optical fibers to discretize the intensity distribution at the telescope focal plane. This allows not only reformatting but also the equalization of fiber output intensities, matching

We present accurate measurements of the central wavelengths of 4947 atomic absorption lines in the solar optical spectrum. The wavelengths, precise to a level ~ 50-150 m s(-1) , are given for both flux and disc-centre spectra, as measured in relatively recent FTS solar atlases. This catalogue modernizes existing sources based on photographic

IAUC 7000 available at Central Bureau for Astronomical Telegrams.

IAUC 6993 available at Central Bureau for Astronomical Telegrams.