News Physics

A nuclear clock prototype hints at ultraprecise timekeeping 

The device could allow for new tests of fundamental physics

A photograph of scientific equipment, including a laser beam illuminating gas inside a vacuum chamber.

Physicists used a laser (shown) to probe a jump between two energy levels in thorium-229, which could serve as a nuclear clock.

Chuankun Zhang/JILA

By Emily Conover

Scientific clockmakers have crafted a prototype of a nuclear clock, hinting at future possibilities for using atomic nuclei to perform precise measurements of time and make new tests of fundamental physics theories.