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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.

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News!

From the Naval Observatory

Recent Press Releases and notices

In Memoriam: Thomas E. Corbin, Ph.D.,
1940 - 2023

We are hiring Supervisory Informational Technology Specialists for our N6 (IT) Department! (02/10/2023)

We are hiring Research Physicists for our Clock Development Division! (01/27/2023)

We are hiring Astronomers for our Celestial Reference Frame Department! (01/27/2023)

USNO Astronomer Leads Effort to Precisely Locate Sagittarius A* in the International Celestial Reference Frame Using Absolute Astrometry (01/19/2023)

USNO Astronomer Makes Major Breakthrough in Unifying the Celestial Reference Frame (12/7/2022)

We are hiring Engineering Technicians! (12/1/2022)

USNO Astronomer Leads Study that Questions Structure of the Universe (10/11/2022)

We are looking for an Archivist! (10/3/2022)

The "Shortest" Day? (8/8/2022)

USNO Astronomers Create New Catalog of the Fundamental Properties of Supermassive Black Holes that Comprise the ICRF (6/17/2022)

Captain Hartwell F. "Rip" Coke becomes 58th Superintendent, U.S. Naval Observatory (1/12/2022)

USNO Marks 50 Year Anniversary of Breakthrough Relativity Experiment (10/15/2021)

USNO Astronomer Leads Breakthrough Study that Questions Current Cosmological Understanding of the Universe (3/1/2021)

USNO Astronomers Peer into Hearts of Supermassive Black Holes; Discover New Relationships Between “Quiet” and “Noisy” Black Holes (3/1/2021)

Are Negative Leap Seconds In Our Future? (2/11/2021)

In Memoriam: Paul D. Shankland, Ph.D.,
1961 - 2020

In Memoriam: Victor J. Slabinski, Ph.D.,
1940 - 2020

USNO’s James M. Gilliss Library Joins Consortium  (4/14/2020)

USNO Staff Members Named as First AAS Fellows  (4/10/2020)

USNO Breaks Ground on New Master Clock Facility  (2/10/2020)

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