A new atomic clock is one of the world’s best timekeepers, researchers say — and after years of development, the “fountain”-style clock is now in use helping keep official U.S. time. Known as NIST-F4, ...

Every single day, humans rely on hundreds of hidden clocks. GPS location, Internet stability, stock trading, power grid management ... all rely on atomic clocks in order to work. Many of those clocks ...

The clock is so reliable that it would be off by less than a second if it had started running 100 million years ago, researchers say. A new atomic clock is one of the world’s best timekeepers, ...