Add Yahoo as a preferred source to see more of our stories on Google. (Adam Gault/Photographer's Choice RF/Getty Images) Researchers in China have created one of the most precise clocks ever made – so ...

A string of experiments using thorium-229 nuclei has brought the long-theorized nuclear clock closer to reality, producing frequency measurements stable enough to challenge the atomic clocks that ...

The way the world measures time could be heading for a rare and significant overhaul. Advances in precision technology are prompting scientists to reconsider one of the most fundamental units in ...

For the first time, an international team of physicists has successfully harnessed a rare orbital transition in atoms of ...