United States Naval Observatory
The U.S. Naval Observatory
is one of the oldest scientific
agencies in the USA
. Established in 1830
as the Depot of Charts and Instruments
, its primary mission was to care for the U.S. Navy
's chronometers, charts and other navigational equipment. Its most important task was the calibration of ship's chronometers, which was accomplished by timing the transit
across the meridian
Today, the U.S. Naval Observatory is the preeminent authority in the areas of time keeping and celestial observing; determining and distributing the timing and astronomical data required for accurate navigation and fundamental astronomy.
Since 1974, Number One Observatory Circle has been the official residence of the Vice President of the United States.