Today will be one second longer
DOI: 10.1063/PT.5.028998
BBC : Today, 30 June, timekeepers around the world will be adding one more second to the day, called a leap second. Leap seconds have been added periodically since 1972 to help keep the Coordinated Universal Time system running close to mean solar time, which varies because of Earth’s irregular rate of rotation. So far, 25 leap seconds have been added—the last exactly three years ago today. However, objections have been raised because of the problems the tiny correction causes for computer systems, which rely on precise timekeeping and must be reprogrammed manually to handle the irregular adjustments. The issue is to be discussed at the upcoming World Radiocommunication Conference in Geneva in November.