For many years, cesium atomic clocks have been reliably keeping time around the world. But the future belongs to even more ...

Smaller version Illustration of a conventional atomic fountain clock (left) next to NPL’s miniature atomic fountain clock.

The way in which time progresses on the Moon is becoming increasingly relevant as both countries push toward their next lunar ...

Tracking time is one of those things that seems easy, until you really start to get into the details of what time actually is. We define a second as 9,192,631,770 oscillations of a cesium atom.

Vladan Vuletić with members of his Experimental Atomic Physics group. From left to right: Matthew Radzihovsky, Leon Zaporski, Qi Liu, Vladan Vuletić, and Gustavo Velez. Every time you check the time ...