NIST Launches a New U.S. Time Standard: NIST-F2 Atomic Clock
NIST-F2 would neither gain nor lose one second in about 300 million years, making it about three times as accurate as NIST-F1, which has served as the standard since 1999. Both clocks use a "fountain" of cesium atoms to determine the exact length of a second.
Continue Reading http://www.nist.gov
Join the Discussion