US Naval Observatory

 The United States Naval Observatory, headquartered in Washington, DC, is one of the oldest scientific agencies in the federal government.  It was established in 1830 as the Depot of Charts and Instruments, with the primary mission of caring for the US Navy’s chronometers, charts, and other navigational instruments.  In 1842, Congress authorized the relocation of the facility (then called the National Observatory) to University Circle (present site of the Department of State).  The first Superintendent of the new Observatory was Commander Matthew Fontaine Maury, who placed into service a vulcanized time ball to signal the arrival of noon for ships in the area.  Unfortunately, the location is called “Foggy Bottom” for a reason and the time ball proved of minimal value.  In 1893, the Observatory was moved to its present location on a hill overlooking Massachusetts Avenue (which since 1974 has also served as the official residence of the Vice President of the United States).  The Observatory was equipped with a 40-inch telescope, but light pollution in the area adversely impacted the usefulness of this instrument.   In 1955, the telescope was moved to the new Naval Observatory Flagstaff Station in Arizona.  The Naval Observatory continues to provide a wide range of astronomical data and products and serves as the official source of time for the Department of Defense (including the Global Positioning System – GPS) and a standard of time for the entire nation.  In this regard, it operates about 100 cesium atomic clocks, hydrogen masers, and rubidium atomic fountain clocks at locations in Washington, DC and Colorado Springs.  The Observatory is also the publisher of the Astronomical Almanac and the Nautical Almanac.