Southwest Oklahoma's Resource For News and Entertainment
Thursday September 21st 2017

Leap Year

February 2012 calendarBefore I tell you what I’ve found out about Leap Year and its history, I’d like to warn you.  When I told my editor that I’d write about Leap Year I thought, “This will be a fun and hopefully interesting subject for the magazine.”  I did find it interesting, I learned things that I’d never known before about different calendars, but there were times when I had to stop reading about it and walk away.  I’m going to try and simplify it as much as possible, but I won’t feel slighted if you need to put it down and come back to it.  Now that that is out of the way, let me tell you a little about leap years.

This year is election year.  Wait, let me start over…this year is a leap year.  I remember when I was growing up that if it was leap year, then it was election year.  That has nothing to do with the meaning of leap year, but I thought I throw that in there.

Leap year was instituted for a pretty basic reason:  to keep the calendar even with the solar year.  It takes the earth 365.2422 days to make one pass around the sun.  It’s the 0.2422 of a day that messes with the calendar.  This wouldn’t be a big deal if there weren’t religious and seasonal celebrations that need to occur on certain days on the year.  But there are.  So, there had to be some sort of system that could be used to keep everything relatively close.

Calendar reform came during the time that the Roman Empire was ruling.  Roman had taken to adding months to the calendar, wherever they pleased and for however long, to keep up with the solar year.  It was sometime between 305 and 30 B.C. that the Egyptians adopted a leap year system.  Cleopatra introduced the leap year to her lover, Julius Caesar, who instituted a single year that was 445 days long, in order to realign the calendar with the solar calendar.  The reformed calendar was organized into 12 month and 365 days with a leap year every four years, and was called the Julian calendar.

Here’s where it gets a little bumpy.  The extra day that was added made it so that every four years there was a discrepancy of 11 minutes per year.  What seems like a minor issue, was actually making the Julian calendar off by one day every 128 years.  So, Pope Gregory XIII, convinced by his astronomers that the Christian holidays were not being celebrated on the correct days, introduced the Gregorian calendar in 1582.  Pope Gregory decreed that only one out of every four “century years” would include a leap year.  So, while 2000 and 2400 are leap years, 2100, 2200, and 2300 are not.

There are three criteria that must be met for a Gregorian calendar to be a leap year. First, it must be evenly divided by 4.  Second, if it can be evenly divided by 100, then it isn’t a leap year, unless – Third, the year is evenly divided by 400, at which point the year is a leap year.  In the year 2000, the third criterion was used for the first time around the world.

Related Tags:

Leave a Comment