Note: USNO-A1.0 contains 488,006,860 sources, and was compiled from the blue/red overlaps of the detection lists generated from scans of POSS-I O and E plates (>=-30°) and SRC-J and ESO-R plates (<=-35°). USNO-A1.0 was created by Dave Monet () and collaborators at Flagstaff Station, U.S. Naval Observatory; it is superseded by the new PMM-USNO-A2.0 version. The VizieR search engine uses an on-line compressed version (3.4Gbytes) which was generated at CDS.
Note: The Guide Star Catalog has been constructed to support the operational need of the Hubble Space Telescope. It contains over 25 million positions for about 19 million objects, of which more than 15 million are classified as stars. The version 1.2 is a new astrometric reduction which results in absolute position errors about 0.3-0.4 arcsec. (see GSC pages at URL http://www-gsss.stsci.edu/gsc/gsc.html)
Note: The Naval Observatory Merged Astrometric Dataset (NOMAD) contains astrometric and photometric data for over 1 billion stars derived from the Hipparcos (I/239), Tycho-2 (I/259), UCAC2 (I/289), and USNO-B1.0 (I/284) catalogs for astrometry and optical photometry, supplemented by 2MASS (II/246) near-infrared photometry. An efficient remote query program findnomad1 is available in the cdsclient package, for Unix/Linux platforms
Note: The limiting magnitude is about 15.2 in the GSC photometric system.
Note: see the UCAC4 document, and the the fix for high proper motion stars. The UCAC home page is available at http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/ucac. Please acknowledge the usage of the UCAC4
Note:
Note: UCAC5 document
(original column names in green) (1692919135 rows)
(original column names in green) (1811709771 rows)
Note: SDSS is also available from http://www.sdss.org/
