June 30 Will Have An Extra Second: NASA

29 June, New York

June 30 this year will officially be a bit longer than usual because an extra second, or ‘leap’ second, will be added to the day, according to NASA.

Daniel MacMillan of NASA’s Goddard Space Flight Centre said that the Earth’s rotation is gradually slowing down a bit, so leap seconds are a way to account for that.

Strictly speaking, a day lasts 86,400 seconds. That is the case, according to the time standard that people use in their daily lives – Coordinated Universal Time, or UTC.

However, the mean solar day – the average length of a day, based on how long it takes Earth to rotate, is about 86,400.002 seconds long.