We present initial results from a water-vapour monitoring campaign initiated in 1996. A certain amount of caution must still be applied to the interpretation of the water-vapour statistics as a large majority of the data have been taken in summer, or autumn. Continued monitoring is accumulating strong evidence of a seasonal effect, with typically

The velocity field of the nearly face-on galaxy NGC 3631 is derived from observations in the Hα line on the 6-m telescope of the Special Astrophysical Observatory. These optical data are compared with radio observations of this galaxy (Knapen 1997). It is argued that the two-armed spiral structure of NGC 3631 has a wave nature, and that the

It is planned to include adaptive optics as an integral part of the 10-m Gran Telescopio Canarias. Preliminary scientific requirements have been drawn up, and it is necessary to identify systems which will satisfy these requirements. The approach adopted here is to use the LACE program to model the adaptive-optics system. The program provides for

Using a large amount of data gathered during previous seeing campaign at ORM, we analyse the temporal evolution of seeing in order to find out whether predictions could be made over a short time interval of a few hours. The first results are presented.

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