News Physics

Physicists take a major step toward making a nuclear clock

In a first, a tabletop laser nudged a thorium nucleus into a higher energy state 

A split illustration shows a thorium nucleus alongside a clock.

Scientists have taken a step toward building a nuclear clock out of thorium-229.

Mustapha Laatiaoui

By Emily Conover

The time is nigh for nuclear clocks. 

In a first, scientists have used a tabletop laser to bump an atomic nucleus into a higher energy state. It’s a feat that sets scientists on a path toward creating the first nuclear clock, which would keep time based on the inner workings of atomic nuclei.