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The U.S. Naval Observatory's Georgetown Heights Headquarters, as completed in 1893.
Richard Morris Hunt, Architect


Welcome to the United States Naval Observatory's Official Web Page


The U.S. Naval Observatory Seal

The U.S. Naval Observatory Seal, designed in 1867 by RADM Charles Henry Davis

The U.S. Naval Observatory (USNO) provides a wide range of astronomical data and products, and serves as the official source of time for the U.S. Department of Defense, and a standard of time for the entire U.S. 

Founded in 1830 as the U.S. Navy Depot of Charts and Instruments, USNO is recognized as the world's foremost authority on spatial and temporal reference frames.

USNO is headquartered in Washington, D.C., and operates a dark-sky observing station near Flagstaff, Arizona (NOFS). It also has a small detachment activity, the Alternate Master Clock facility (AMC), located at Schriever Space Force Base in Colorado Springs, Colorado.

 
USNO Menu


Need to know what time it is?
Visit
time.gov
 
 
Commander, Naval Meteorology and Oceanography Command | 1100 Balch Blvd. | Stennis Space Center, Mississippi 39529