Thirty days hath September,
April, June and November.
All the rest have thirty one
February alone has twenty eight
Leap Year coming once in four
February then has one day more.
……Traditional English rhyme

As children most of us probably memorized this verse or something similar. There are numerous variations, but all serve the same purpose – to help remember the number of days in each month.

2016 is a Leap Year and “February then has one day more.” That one day, February 29, is called a Leap Day. Why does our calendar have an extra day every four years? An additional day, the 29th, is added to February’s calendar every four years to keep our calendar synchronized with the earth’s revolutions around the sun. The earth takes slightly more than 365 days to revolve around the sun – 365 days, 5 hours, 48 minutes and 46 seconds. This isn’t a huge amount of time per year, but in one hundred years, that extra amount of time would cause calendars to be inaccurate by about twenty four days. To keep our calendars accurate, Leap Years were added.

The earliest Leap Year was introduced by Julius Caesar (100-44 BC). Julian Calendar Leap Years were those that could be evenly divided by four; this rule created too many Leap Years, and the calendar became inaccurate in regard to seasons, but it was not corrected until the Gregorian Calendar was introduced by Pope Gregory XIII in 1582. In the Gregorian Calendar Leap Years are determined by three factors: (1) the year must be evenly divided by four, (2) “if the year can be evenly divided by 100, it is NOT a leap year, unless; (3) the year is also evenly divisible by 400.” Thus, the next Leap Year will be 2020 and its Leap Day will be Saturday, February 29.

So this month we will all have an extra day in February. How will you spend your Leap Day?