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We present some preliminary results of a spectroscopic study of the cataclysmic system IR Gem at quiescence during two orbital periods. The spectra covered the wavelength range 4000 7000 Å. The variations with the phase in the equivalent width of the Hα line confirms the existence of a maximum at phase 0.5.

The detection of high late-time luminosity in the type-II plateau supernova 1988A about 500 days after maximum indicates that some mechanism is still providing large amounts of energy to the supernova at this very late phase. We present a review of the observations of this supernova at different phases, and examine the possible mechanisms that can

We present some preliminary results of a time-resolved spectroscopic study of the peculiar cataclysmic system AM CVn. The analysis of He i lines profile variability, suggests the existence of a 1051 s periodicity. This is one of the known photometric periods, candidate to be the orbital period of the system, or the rotational period of the primary.

Visible light curves of the RS CVn short-period system BH Vir, collected over 26 years, have been analyzed.B-V colours indicate that the primary minimum is normally redder than one would expect, assuming the spectroscopic classification of the system components, while the secondary yielded bluer. A qualitative comparison of the different light

The paper presents CCD photometry for stars in three fields centered on the old open cluster NGC 188 and in four fields on the intermediate-age cluster NGC 7789, which has been performed with the aim of investigating the HR diagram distribution of the cluster's Main-Sequence (MS) stars. A sufficiently well-defined sequence of subgiant, turn-off