We’re not celebrating Easter this week, we’re not even planning to celebrate it next month!
In most of Eastern Europe religious holidays are dictated by the Orthodox Church.
The Orthodox Church follows the Julian calendar, which was introduced by Julius Cesar in 45 BC. However, most of the rest of the world follows the Gregorian calendar, which was introduced in 1582 to correct the Julian calendar.
What’s the difference?
The main difference between the two calendars is how leap years are calculated. The Gregorian calendar does not add a leap day to most years that our divisible by 100. Thus the years 1800 and 1900 were not leap years although they are divisible by 4.
The result is that the Gregorian calendar is 10 minutes and 48 seconds per year shorter than the Julian calendar. That means that every 133 years the Julian calendar falls behind by a day. Currently the old Julian Calendar is 13 days behind the newer Gregorian calendar.
Now here’s were it get’s complicated.
The date for Easter changes every year because it is based upon the phases of the moon. Easter always falls on the first Sunday following the first full moon after the Spring Equinox.
For most of the world following the newer Gregorian calendar Easter can fall between March 22nd and April 25th. However, for Ukrainians and others living in predominant Orthodox countries the dates for Easter can fall between April 4th and May 8th!
This year our Easter falls on May 5th, that’s 35 days after Western Easter!
Now here’s the weird part. If the full moon occurs more than 13 days after the spring equinox then the Western and Eastern dates for Easter align and we celebrate together! This will happen in 2014 when Easter will be on April 20th for both the Julian and Gregorian calendars.