We present observations of the evolution of a prominent spiral jet in the inner coma of comet Hale-Bopp (1995 O1). The observations, taken with the 82 cm IAC-80 telescope at the Teide Observatory, were made on 1995 August 25, 27, 28, and 31, and on September 4--7, as part of an ongoing program of monitoring the comet in Tenerife. The jet is

LA EXISTENCIA DE POLVO EN LAS REGIONES DE EMISION DE LINEAS ESTRECHAS Y SUS EFECTOS EN LA GENERACION DE LAS MISMAS ES UNO DE LOS TEMAS MAS INTERESANTES DE LA FISICA DE LAS GALAXIAS ACTIVAS.EN LA MEMORIA SE ANALIZAN, DESDE PUNTOS DE VISTA MUY CONCRETOS, EVITANDO CONSTRUIR MODELOS CON MUCHOS PARAMETROS LIBRES, LOS MECANISMOS QUE CONTROLAN LA

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