SAO Star Catalog

These files contain the entire SAO catalog of 258,996 stars, including
B1950 positions, proper motions, magnitudes, and, usually, spectral types in
a locally-developed binary format described below.
While the SAO catalog is more or less complete to V=9, with 4,503 stars
fainter than V=10, the PPM catalog is fairly
complete to V=9.5, with 102,672 stars fainter than V=10 and 22,395 stars
fainter than V=11.

SAO is sorted by increasing ID number, with B1950 coordinates,
and is arranged in 18 10-degree bands of declination, starting with 80-90,
sorted by right ascension within each band. It is used by the program
ssao (which calls
scat)
when the SAO number is known and position, magnitude, and/or spectral
type information is desired.

SAOra, the RA-sorted version, is used for fast searches, at least away
from the poles, by the program
ssao (which calls
scat)
and for plotting by skymap.

A gzipped 11,586,492-byte file containing both files in Sun/Mac byte order
is available here as sao.tar.gz.
A gzipped 11,565,967-byte file containing both files in PC/Alpha byte order
is available here as saopc.tar.gz.
star and
scat
can read these files on machines with either byte order.

SAO is a 8,287,900-byte file, and
SAOra is a 8,287,900-byte file.

Detailed descriptions of the
binary header format
and
binary entry format are available.

An ASCII version with more information for each star is available from NASA’s

High Energy Astrophysics Science Archive Research Center (HEASARC) at

ftp://legacy.gsfc.nasa.gov/heasarc/dbase/dump/heasarc_sao.tdat.gz.
Online documentation is available at

http://heasarc.gsfc.nasa.gov/W3Browse/star-catalog/sao.html.

[rsao]
[WCSTools ssao]