Note: USNO-A2.0 contains 526,280,881 sources, and is based on a re-reduction of the Precision Measuring Machine (PMM) scans from POSS-I O and E plates (>=-18°) and SRC-J and ESO-R plates (<=-20°). USNO-A2.0 was created by Dave Monet () and collaborators at Flagstaff Station, U.S. Naval Observatory.
The major difference between USNO-A2.0 and its previous version USNO-A1.0 is that A1.0 used the Guide Star Catalog as its reference frame whereas A2.0 uses the ICRF as realized by the USNO ACT catalog (Urban et al. 1997). The VizieR search engine uses an on-line compressed version (3.6Gbytes) which was generated at CDS.

I/252/out

The USNO-A2.0 Catalogue (Monet+ 1998) ReadMe+ftp metaI/252/out The Full Catalogue (526280881 rows) (Note)

Note: The construction of the GSC-II is still in progress: this version has no proper motions, and the magnitude limits are 18.5 in F (red) and 19.5 in J (blue). The data are copyrighted, check the data use Policy.

I/271/out

The GSC 2.2 Catalogue (STScI, 2001) ReadMe+ftp metaI/271/out The Full GSC2.2.1 Catalogue (455851237 objects) (455851237 rows)

Note: The USNO-B Catalog presents positions, proper motions, magnitudes un blue, red and infrared, as well as star/galaxy estimators for 1,045,175,762 objects derived from 3,648,832,040 separate observations. The data were taken from scans of 7,435 Schmidt plates taken from various sky surveys during the last 50 years.
USNO-B1.0 catalog was created by Dave Monet and collaborators at http://www.nofs.navy.mil/data/fchpix/
Note that the star/galaxy estimators may be mixed up in dense regions.

I/284/out

The USNO-B1.0 Catalog (Monet+ 2003) ReadMe+ftp 2003AJ....125..984M metaI/284/out The Whole-Sky USNO-B1.0 Catalog of 1,045,913,669 sources (1045175762 rows)

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

I/297/out

NOMAD Catalog (Zacharias+ 2005) ReadMe+ftp 2004AAS...205.4815Z metaI/297/out The NOMAD-1 Catalog (1117612732 rows)

Note: This version of the GSC-II has no proper motions, but the limits on brightness which existed on GSC2.2 (F<18.5, B_j<19.5) were removed.

I/305/out

The Guide Star Catalog, Version 2.3.2 (GSC2.3) (STScI, 2006) ReadMe+ftp 2008AJ....136..735L metaI/305/out The Full GSC2.3.2 Catalogue (945592683 objects) (945592683 rows)

I/317/sample

The PPMXL Catalog (Roeser+ 2010) ReadMe+ftp 2010AJ....139.2440R metaI/317/sample PPMXL catalog of positions and proper motions on the ICRS (910469430 rows)

I/319/xpm

XPM Catalog of positions and proper motions (Fedorov+ 2011) ReadMe+ftp 2011MNRAS.416..403F metaI/319/xpm XPM catalogue (original column names in green) (313610083 rows)

Note:

I/320/spm4

SPM 4.0 Catalog (Girard+, 2011) ReadMe+ftp 2011AJ....142...15G metaI/320/spm4 Yale/San Juan Southern Proper Motion Catalog 4 (SPM4) (103319647 rows)

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

I/322A/out

UCAC4 Catalogue (Zacharias+, 2012) ReadMe+ftp 2012yCat.1322....0Z metaI/322A/out Fourth U.S. Naval Observatory CCD Astrograph Catalog (113780093 rows)

Note:

I/324/igsl3

The Initial Gaia Source List (IGSL) (Smart, 2013) ReadMe+ftp 2013yCat.1324....0S metaI/324/igsl3 IGSL3 data release (1,222,598,530 sources) (1222598530 rows)