Maps of a 3 by 2 arcmin region of the inner coma of comet Halley, at 10 arcsec resolution, in several principal atomic and molecular species were prepared by multiposition absolute spectrophotometry at 3.6 A resolution, in the wavelength range 3700 to 7598 A. The data form a subset of a larger data set collected at a range of heliocentric distances

The authors present low resolution maps, of a four by one half arcminute region, of comet Halley, in photometric bands J and K, and central scan in the H band, taken with the 1.5 m Sanchez-Magro Infrared Flux Collector of the Instituto de Astrofísica de Canarias, situated in its Observatorio del Teide. They obtain central and integral magnitudes

We search the literature for reports on the spectral properties of neutron star low-mass X-ray binaries when they have accretion luminosities between 1034 and 1036 erg s-1, corresponding to roughly 0.01-1 per cent of the Eddington accretion rate for a neutron star. We found that in this luminosity range the photon index (obtained from fitting a

Context. Globular clusters show star-to-star abundance variations for light elements that are not yet well understood. The preferred explanation involves a self-enrichment scenario, within which two subsequent generations of stars co-exist in globular clusters. Observations of chemical abundances in the main sequence and sub-giant branch stars

The small imaging photometer of the VIRGO (Variability in IRradiance and Gravity Oscillations) investigation on ESA's SOHO mission is presented. This instrument, the Luminosity Oscillations Imager (LOI), will observe the solar radiance with 12 pixels resolution. A prototype of the LOI was built mainly to test possible detector configurations, the

We propose to use the OSIRIS tunable filters to perform for the first time a systematic study of the environment of Radio Loud and Radio Quiet quasars in windows around a large range of redshifts (z ~ 2 to 4). The aim of our study is (1) to search for the presence of forming clusters of galaxies around quasars, through Ly α emitters, which in turn