Advancing the Clocks

On the early hours of Sunday 14 March 2021, most of the United States will put their clocks forward an hour and Daylight Saving Time (DST) will commence. Two weeks later on 28 March most countries in Europe (including the UK) will follow, switching to  summer time. In this post I’ll talk about the practice… Continue reading Advancing the Clocks

December 31 2016 Leap Second

On New Year's Eve an extra second will be added to the end of the day. This extra second is called a leap second. As I'll explain later, leap seconds need to be added periodically to bring the time we measure with accurate atomic clocks in line with the natural time which results from the rotation of the… Continue reading December 31 2016 Leap Second

Jun 30 2015 – Leap Second

On June 30 2015 an extra second will be inserted into the very end of the day. This extra second is called a leap second.   Why do we need leap seconds? Although we take the average length of a day to be 24 hours, the mean solar day, or average "natural" day measured by the… Continue reading Jun 30 2015 – Leap Second