Note: Detailed introduction can be found in intro.tex (see also http://aries.usno.navy.mil/ad/ac.html) Direct links to Hipparcos and Tycho observations are provided from the relevant columns.
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
Please acknowledge the usage
of the UCAC4
(original column names in green) (1692919135 rows)
(original column names in green) (1811709771 rows)
Note: Many errors detected in the positions given in the catalogue, especially in the sign of the declination in the zones -1°<δ<+1°
Note: Errors found in the Final IUE Merged log are reported in the file errata.htx
Note: on-line documentation at http://www.swift.ac.uk/2SXPS/docs.php
Note: See also the DENIS home page
Note: Details of surveyed literature