X-ray catalogsThese have been published following successive (and increasingly sensitive) all-sky surveys. The first sky-survey mission was Uhuru, which led finally to the 4U catalog published in 1978. The Ariel V survey yielded the 3A catalog in 1981, followed by the more sensitive HEAO-1 catalog in 1984. ROSAT was the next spacecraft to carry out an all-sky X-ray survey, in 1990–91, yielding over 60 000 source detections (not yet published). ROSAT was also responsible for the first all-sky survey in the XUV waveband: the Bright Source Catalog, containing 384 XUV sources, was published in 1993, with a more extensive version of 479 XUV sources following in 1995.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006