(CNN) -- Timekeeping in the United States, which was already a pretty precise science involving lasers and atomic particles, just got even more exact.

A new atomic clock, so accurate it will lose or gain only one second every 300 million years, was unveiled Thursday by the National Institute of Standards and Technology, a branch of the U.S. Department of Commerce.

The NIST-F2 had been in development for about a decade and is three times more accurate than the F1, which has been in use since 1999. The institute will continue operating both clocks for now at its campus in Boulder, Colorado.

The clock is used for civilian purposes in the United States and its data is shared with the International Bureau of Weights and Measures in Paris.

http://edition.cnn.com/2014/04/03/te...ock/index.html