Meet the zeptosecond, the shortest unit of time ever measured

Scientists have measured the shortest unit of time ever: the time it takes a light particle to cross a hydrogen molecule.  That time, for the record, is 247 zeptoseconds. A zeptosecond is a trillionth of a billionth of a second, or a decimal point followed by 21 zeroes and a 1. Previously, researchers had dipped […]