Symbiotic stars, which are interacting binary stars usually composed by a late type giant and a very hot/luminous white dwarf, are a powerful laboratory to investigate mass loss phenomenon relevant to a wide range of astrophysical topics: aspherical mass loss, collimated winds from accretion disks, colliding winds, mass loss induced by violent

Near-Infrared J H K images are presented for a small sample of HII galaxies observed at UKIRT. Based on NIR colours, comparison with the stellar population models allowed us to further discuss the history of star formation in these bursting dwarf galaxies. Light and colour profiles are used to investigate their possible links with other types of

The Instituto de Astrofisica de Canarias (IAC, http://www.iac.es/) is promoting the construction of a segmented 10m Telescope to be placed at its Observatorio del Roque de Los Muchachos (ORM) in the island of La Palma, Spain. The Telescope scientific drivers are to achieve an outstanding image quality, to maximize the observing efficiency and to

Data for five continuous years (1984 to 1989) at the Teide Observatory (Izaña, Tenerife), obtained with a full-disc solar multi-channel photometer devoted to the detection of solar intensity oscillations have now been used for a detailed study of the extinction coefficient behaviour at several wavelengths (450-870 nm) under different atmospheric

The outstanding quality of the Canarian sky, protected by law, makes it feasible to install the largest telescopes in the world at the observatories of the Instituto de Astrofísica de Canarias (IAC), which has promoted the design and construction of the Gran Telescopio Canarias (GTC). The GTC is a high-performance 10-m class telescope to be

We have obtained low-resolution optical spectra of three faint brown dwarf candidates in the Pleiades open cluster. The objects observed are Roque 12 (I_C=18.5), Roque 5 (I_C=19.7), and Roque 25 (I_C=21.2). The spectrum of Roque 25 does not show the strong TiO band heads that characterize the optical spectra of M-type stars, but molecular bands of