THE FIRST U.S. NAVAL OBSERVATORY ROBOTIC ASTROMETRIC TELESCOPE CATALOG

URAT1 is an observational, astrometric catalog covering most of the Dec >= -15 deg area and a magnitude range of about R = 3 to 18.5. Accurate positions (typically 10 to 30 mas standard error) are given for over 228 million objects at a mean epoch around 2013.5. For the over 188 million objects matc... View More