It is shown here that the ejecta from type II supernovae follow a long excursion into the galactic environment before they mix with the ISM. We point to the various changes in temperature, density, and pressure experienced by the ejecta along their inevitable ride, indicating the main hydrodynamical events and physical processes taking part in

We present high-resolution He I 4471, Mg II 4481 and Hγ line profiles of the Be star 31 Peg obtained simultaneously at four observing dates. In this paper we focus on the He I 4471 line and on the absorption wings of the Hγ line which showed important variations. Models of static stellar atmospheres were calculated to determine the photospheric

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.