Smithsonian Astrophysical Observatory Star Catalog

The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue, created by Smithsonian Institution, a research institute. It was published by the Smithsonian Astrophysical Observatory in 1966 and contains 258,997 stars.[1][2][3][4] The catalogue was compiled from various previous astrometric catalogues, and contains only stars to about ninth magnitude for which accurate proper motions were known. Names in the SAO catalogue start with the letters SAO, followed by a number. The numbers are assigned following 18 ten-degree bands of declination, with stars sorted by right ascension within each band.

Smithsonian Astrophysical Observatory Star Catalog
Alternative namesSAO

Online version of the SAO Catalog was created by the HEASARC in March 2001 based on ADC/CDS Catalog I/131A, which itself is originally derived from a character-coded machine-readable version of the Smithsonian Astrophysical Observatory Star Catalog (SAO, SAO Staff 1966) prepared by T.A. Nagy in 1979, and subsequently modified over the next decade or so.[5]

Examples of SAO catalogue entriesEdit


  1. ^ Star Catalog: Positions and Proper Motions of 258,997 Stars for the Epoch and Equinox of 1950.0, Smithsonian Astrophysical Observatory Staff, Publications of the Smithsonian Institution of Washington, D.C., no. 4652, 4 vols., 1966 (reprinted 1971.)
  2. ^ Webpage on the SAO star catalog, B1950
  3. ^ Catalog translated to J2000
  4. ^ Interactive query form of the catalog
  5. ^ "SAO - Smithsonian Astrophysical Observatory Star Catalog". Retrieved 2021-10-01.
  6. ^ Millis, R. L.; Wasserman, L. H.; Birch, P. V. (1977). "Detection of rings around Uranus". Nature. 267: 330–331. Bibcode:1977Natur.267..330M. doi:10.1038/267330a0.