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October 19, 2019
About the Astrometry Department
The Astrometry Department of the U.S. Naval Observatory is responsible
for the determination of fundamental positions, motions and distances
of selected celestial objects. Observations made with special
astronomical instruments are used to conduct investigations on
characteristics of these objects and to determine their relative
positions for the purpose of establishing reference frames in the sky.
Advanced equipment and methods, such as the Full-sky Astrometric
Mapping Explorer (FAME) spacecraft, large scale CCD measuring devices,
speckle and radio interferometry, are being used or developed to
extend the accuracy and brightness limits of the reference frames. The
results of the observational programs are published in the Naval
Observatory Publications and in refereed journals. The observational
results are required by the Navy and the Department of Defense, the
national and international astronomical communities, and by other
governmental and private organizations. The Astrometry Department, a
world-recognized leader in its field and the only organization within
the United States performing this type of work, employs astrometric
specialists who use highly sophisticated precision instrumentation and
advanced data analysis tools in carrying out the work of the
The Astrometry Department is composed of three divisions.
- Cataloging and Requirements Division:
Assembles observations into astrometric
catalogs and combines observational catalogs into combined
catalogs. Investigates the characteristics of catalogs. Determines
- Astrometric Satellite Division:
- Fundamental Reference Frame Division:
The Department maintains telescopes in Washington, DC and Cerro
Tololo, Chile. It operates the Starscan plate measuring machine. It
also operates an instrument shop for the
construction of new equipment, the development of new astronomical
instrumentation and the maintenance of existing equipment. The
instrument shop operates numerous numerically controlled machine tools
and CAD/CAM systems.
Other astrometric programs are also done with the Navy Prototype Optical
Interferometer and other instruments at the Naval Observatory Flagstaff
Station in Flagstaff, Arizona.
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