Considerable interest has been raised by the discovery of Comet Hale-Bopp (1995 O1) and the possibility that it might become a very bright object in Spring 1997. The evidence to support either of the conflicting hypothesis (an intrinsically bright comet or a faint comet in a very large outburst) is too limited to reach solid conclusions and may

IAUC 6370 available at Central Bureau for Astronomical Telegrams.

Time resolved spectra of SS Cyg corresponding to different outburst types are analyzed. Some evidence has been found for an increase of the mass transfer rate from the secondary star as the mechanism responsible for symmetric outburst. Heating of the secondary star has been found during the rise to an asymmetric outburst which appears to be

The authors present high signal-to-noise ratio spectrophotometry obtained in the optical and near-infrared with the double spectrograph ISIS on the WHT, of the M33 giant H II region NGC 604. The authors' main aim was to deduce global properties of a nearby giant H II region. The near-infrared spectral range, central to the authors' study, comprises

QUIZA LA FORMA MAS DIRECTA DE MEDIR LA IMPORTANCIA DE LA HELIOSISMOLOGIA COMO HERRAMIENTA PARA ESTUDIAR EL INTERIOR SOLAR SEA EL DAR CUENTA DEL INMENSO ESFUERZO OBSERVACIONAL REALIZADO EN LOS ULTIMOS AÑOS. LOS EXPERIMENTOS A BORDO DE SOHO, LA RED GONG Y LOS DATOS DEL ESPECTRO-FOTOMETRO MARK I, ENTRE OTROS, SE ESPERA SUMINISTREN DATOS DE ALTISIMA

Since the discovery of very low-Ti (VLT) basalts as tiny clasts and glasses in Apollo 17 drill cores, VLT basalts have been recognized as an important lunar rock type. Lunar sample 78526 (8.77 g), our largest specimen of VLT basaltic composition, is an impact melt composed of vitrophyric green glass with minor lithic and mineral inclusions. Major