How Is The Date For Easter Determined?

Happy Ash Wednesday!

For those of us who are Catholic, today is the beginning of Lent, also known as the day we get ashes smeared on our forehead.

In just 46 days we will celebrate Easter by dressing up for Mass, hunting for eggs, and eating one too many Peeps.

I’ll always been a little confused by the fact that Easter does not fall on the same date every year.

Last year it was March 31st. This year it is April 20th. Given that pattern, one might assume that Easter 2015 would fall in May. But nope, it will be April 5th.

Sounds random to me. But it can’t be…can it?

No better place to find out the truth then on another episode of Wonder Why Wednesday

How Is The Date For Easter Determined?

According to, Easter is referred to as a moveable feast. I understand that is what you call a feast day that doesn’t fall on the same date every year, but I think it also sounds like something you might call a food truck.

Jokes aside, the way the date for Easter is decided was determined in 325 at the Council of Nicaea, which set the date of Easter as the Sunday following the paschal full moon, which is the full moon that falls on or after the vernal (spring) equinox.

I am already quite confused, so I am going to quote directly from to make sure I don’t mess anything up.

“For calculation purposes, the full moon is always set at the 14th day of the lunar month (the lunar month begins with the new moon). Likewise, the Church sets the date of the vernal equinox at March 21, even though it can occur on March 20. Both approximations allow the Church to set a universal date for Easter.”

Did you get all that??? Sounds like a space star ordering success story.

I think this might be the first Wonder Why Wednesday that I am even more confused than when I started.

Before I make bad jokes about full moons, I will just stop now and leave it up to the experts to tell me when Easter will take place.

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