The conceptual design of the Gran Telescopio Canarias (GTC) has been completed. One of the challenges facing the GTC Project is to obtain excellent image quality using a segmented primary mirror. The segmentation will introduce a physical effect that contributes to significant degradation of image quality. The image quality requirement imposes the

We present the continuation of our analysis of narrowband [O III] images, obtained using the Hubble Space Telescope (HST), of planetary nebulae (PNs) in the Magellanic Clouds. Six objects, five in the Large Magellanic Cloud, are observed as part of the General Observer program. An additional 15 objects are retrieved from the HST archive. The

The Grain Telescopio CANARIAS (GTC) is a high performance 10-m class telescope which is being built by the IAC (Instituto de Astrofisica de Canarias). It will be installed at the Roque de los Muchachos Observatory, on the island of La Palma. First light is planned for end-2002. Image quality, operational efficiency and reliability are emphasized in

The conceptual design of the GTC optical system was completed in summer of 1997. It will be a Richey Cretien type telescope with a flat tertiary mirror to feed Nasmyth and folded Cassegrain focal stations. The telescope will have a segmented primary mirror and an entrance pupil area equivalent to a circular aperture of 10 m diameter. The details of

A detailed NLTE investigation of Fe I lines is carried out for the MACKKL quiet solar atmospheric model using a very realistic iron atomic model. This improved atomic model consists of about 250 multiplets and nearly 500 UV, optical and IR bound-bound and bound-free transitions including the regime near the Fe I continuum. The authors find and

We have performed a deep, wide-field imaging survey of the Pleiades cluster (Melotte 22) in the R and I-bands to search for very low-mass stars and brown dwarfs. The survey extends over ~ 2.5 square degrees around the cluster's center down to a ~ 90% completeness limit of R ~ 23 and I ~ 22. We find 26 objects whose location in the (I, R-I) color