One of the few quadrennials in addition to the World Cup, the Summer and Winter Olympics and presidential elections is leap year, in which February has 29 instead of the usual 28 days. The reason for this extra 24 hours? Despite what we have been led to believe, the Earth actually takes a little over 365 days to orbit the sun each year, leaving us with around a quarter-day error each calendar year. To make up for this, and to realign the Gregorian calendar with our seasons, an extra day is added every four years.




