The USNO-B Catalog

Abstract

USNO-B is an all-sky catalog that presents positions, proper motions,\nmagnitudes in various optical passbands, and star/galaxy estimators for\n1,042,618,261 objects derived from 3,643,201,733 separate observations. The\ndata were obtained from scans of 7,435 Schmidt plates taken for the various sky\nsurveys during the last 50 years. USNO-B1.0 is believed to provide all-sky\ncoverage, completeness down to V = 21, 0.2 arcsecond astrometric accuracy at\nJ2000, 0.3 magnitude photometric accuracy in up to five colors, and 85%\naccuracy for distinguishing stars from non-stellar objects. A brief discussion\nof various issues is given here, but the actual data are available from\nhttp://www.nofs.navy.mil and other sites.\n