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

Time will no longer be imposed upon us by a cesium fountain clock at the National Institute of Standards and Technology,” ...

The symbolic Doomsday Clock has been maintained by the Bulletin of the Atomic Scientists since 1947.

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

Researchers at the UK’s National Physical Laboratory (NPL) have created a tiny atomic fountain ...

Atomic clocks have long served as the benchmark for precise timekeeping by utilising the stable frequency of atomic transitions as a reference. Recent developments focus on harnessing coherent ...

The way time is measured is on the edge of a historic upgrade. At the heart of this change is a new kind of atomic clock that uses light instead of microwaves. This shift means timekeeping could ...

On Jan. 27, the Bulletin's Science and Security Board will reveal the 2026 Doomsday Clock time during a live, in-person news ...

For decades, atomic clocks have provided the most stable means of timekeeping. They measure time by oscillating in step with the resonant frequency of atoms, a method so accurate that it serves as the ...

NIST scientists have published results establishing a new atomic clock, NIST-F4, as one of the world’s most accurate timekeepers, priming the clock to be recognized as a primary frequency standard — ...

The 2025 decision of the Bulletin of the Atomic Scientists to move the Doomsday Clock to 89 seconds to midnight was the ...