(PCM) 2015 marks the year that a leap second will be added to clocks around the world. It was announced by the officials at the International Earth Rotation and Reference Systems Service in Paris that the second will be added at the 23:59:59 mark on June 30, 2015.
The last time a leap second was added to clocks was back in June of 2012. The leap second is added to clocks as a way to correct desynchronization between Universal Time (marked by Earth’s rotation) and Atomic Time (the average of about 200 atomic clocks in laboratories around the world). The leap seconds if necessary are added to the clock in either June or December.