So tomorrow is March 1, 2018. So why isn't it February 29th? I bet this question has been asked a few thousand times…Why do we have Leap Year or Leap Day anyway?  Well here is your answer.For the Earth to completely rotate around the sun it would take exactly 365.2422 days to complete.  It is the .2422 of a day that throws everything off.  Since we all use the Gregorian Calendar of 365 days in a year, over a four year time period (4 X .2422) we would be needing .9688 of a day to catch up with the calendar.

So every fourth year a leap day is added to February to balance the Gregorian Calendar and solar system’s disparity in rotation time around the sun. That day was added in 2016. So the next leap year and day will be in 2020. In case you were wondering, the Gregorian Calendar, named after Pope Gregory XIII, was introduced in 1582.