The ACT Reference Catalog
Obtaining the Catalog
The ACT Reference Catalog was a primary source of astrometric information
following the release of Tycho-1. In early 2000, this catalog was all
but superseded with the release of
The Tycho-2 Catalogue,
which contains 2.5 million stars compared to ACT's 1.0 million.
Copies of Tycho-2 on CD-ROM are still available
by contacting either Erik Hoeg at
or Sean Urban at
With that said, this webpage and its links will continue to give
information regarding the ACT Reference Catalog, even if only for
Please read the following disclaimer:
- The data provided herein are to be credited to the U.S. Naval Observatory
in any application.
- The data are provided with no warranty as to usefulness or suitability for
a given application.
- Data such as that provided here are available from the USNO to anyone
who requests it, provided the request can be filled without impact on
Please cite the following publication when utilizing the ACT
The data are currently being provided only through the data centers.
- The ACT Reference Catalog
Sean E. Urban, Thomas E. Corbin and Gary L. Wycoff
Astronomical Journal, Vol. 115 (No 1709) pp 2161-2166
To download the data from NASA's
Astronomical Data Center (ADC)
CLICK HERE (ACT Reference Catalog).
Those finding the links to Europe faster can find the data at the
Centre de Donnes Astronomique de Strasbourg, CDS. To link directly to
the catalog at the CDS,
Those finding the links to Japan faster can find the data at the
Japanese Astronomical Data Analysis Center. To link directly to
the catalog at the Japanese ADAC,
[ACT home page |
General Information |
Obtaining the data |
Those requiring additional information
may contact Sean Urban at
This page was last updated November 27, 2001.
Disclaimer for external links