The USNO CCD Astrograph Catalog (UCAC) is an astrometric
star catalog
A star catalogue is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the years, ...
of the
United States Naval Observatory
United States Naval Observatory (USNO) is a scientific and military facility that produces geopositioning, navigation and timekeeping data for the United States Navy and the United States Department of Defense. Established in 1830 as the Depo ...
.
UCAC-1
The first preliminary edition, published in March 2000, gives the positions and proper motions of over 27 million stars in the southern hemisphere in the brightness range 8-16.
UCAC-2
The second issue was the IAU published General Assembly in Sydney (2003) and includes positions and proper motions of about 50 million stars.
UCAC-3
The third edition was published in the IAU General Assembly in Rio (August 2009).
UCAC-4
The fourth edition was published in August 2012.
Since Spring 2015, the successor
URAT Urat may refer to:
* Urad, or Urat, a region in Bayannur, Inner Mongolia
** Urad Front Banner
** Urad Middle Banner
** Urad Rear Banner
*Urat language
Urat (Wasep, Wusyep) is a Torricelli language spoken by a decreasing number of people in Papu ...
is available.
UCAC-5
The fifth edition was published in February 2017.
UCAC5: New Proper Motions using Gaia DR1
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References
External links
UCAC home page
Astronomical catalogues of stars
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