At the dawn of the nuclear age, scientists created the Doomsday Clock as a symbolic representation of how close humanity is to destroying the world. On Tuesday, nearly eight decades later, the clock ...

For the first time, scientists used an atomic nucleus as a clock. The world’s most precise timepieces are made using atoms, specifically their electrons. But clocks based on atomic nuclei — protons ...

Most clocks, from wristwatches to the systems that run GPS and the internet, work by tracking regular, repeating motions. To build a clock, you need something that ticks in a perfectly repeatable way.