The world's principal database of astrometric information on double and multiple stars, maintained at the US Naval Observatory, Washington. The WDS Catalog includes positions, magnitudes, discoverers, position angles, separations, spectral types, and proper motions for the components of over 100 000 systems covering the entire sky. It was first published in 1984, with updated editions in 1996 and 2001. The online version is updated daily.
http://ad.usno.navy.mil/wds/ Full catalogue online, updated daily.
Subjects: Astronomy and Astrophysics.