The epic quest to redefine the second using the world’s best clocks

A more precise definition of the second is crucial to all sorts of physical measurements – but to get there, scientists have to pack up their extraordinarily fragile optical clocks and take them on tour

​A more precise definition of the second is crucial to all sorts of physical measurements – but to get there, scientists have to pack up their extraordinarily fragile optical clocks and take them on tour A more precise definition of the second is crucial to all sorts of physical measurements – but to get there, scientists have to pack up their extraordinarily fragile optical clocks and take them on tour