We present intermediate- and low-resolution optical spectra around Hα and Li I lambda 6708 Åfor a sample of 25 low mass stars and 2 brown dwarfs with confirmed membership in the pre-main sequence stellar sigma Orionis cluster. Our observations are intended to investigate the age of the cluster. The spectral types derived for our target sample are

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We present a spectrophotometric study of short-term optical variability in the quiescent black hole X-ray transient V404 Cyg. This includes two nights of high-time-resolution Hα spectroscopy with which we resolve much of the time variability, and a further six nights of archival spectroscopy with lower time resolution but higher spectral resolution

At the First International Conference on Comet Hale-Bopp (Canaries, 1998) many astronomers agreed with the value of the period of axial rotation of its nucleus, which was obtained by observers by a comparison of the two sequential patterns of the dust arcs. It was noted that the pattern had been repeated each ~12 hours. The value 11.35 h was taken

Globular cluster systems of 17 elliptical galaxies have been studied in the Coma Cluster of galaxies. Surface-brightness fluctuations have been used to determine total populations of globular clusters, and specific frequency (SN) has been evaluated for each individual galaxy. Enormous differences in SN between similar galaxies are found. In

M32 is the prototype for the relatively rare class of galaxies referred to as compact ellipticals. It has been suggested that M32 may be a tidally disturbed r1/4 elliptical galaxy or the remnant bulge of a disk-stripped early-type spiral galaxy. This Letter reveals that the surface brightness profile, the velocity dispersion measurements, and the