Why Easter Hops Around: The Science Behind The Changing Date

INFORMATION FROM 'THE BACKYARD ASTRONOMER'

Gary Boyle, or 'The Backyard Astronomer,' shared some interesting information about how you know what date Easter will fall on.

I'm sure you've been making plans for your Easter family gathering by now and learned that Easter is falling on Sunday, April 20th, this year. But why does the date change from year to year?

Gary informed me that there is a formula to find the date.

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FIRST DAY OF SPRING

It all starts with the first day of spring. Gary says, "You take the first day of spring, March 20th. Find the next full moon (April 13th this year,) then the following Sunday is Easter Sunday." This year, that date is April 20th.

THE FORMULA

So the formula is:
The first day of Spring, the next full moon, and then the following Sunday will be Easter Sunday.

Gary is from Canada, and he shares lots of fun information about our planets and the stars and even has an asteroid named after him. Asteroid 22406 Garyboyle. You can follow his amazing night sky posts on his FB page.

NOT A TRUE FULL MOON

The Royal Museums Greenwich website says that there was no uniform way to figure out the date for Easter until AD 325. It also states that the figures are not completely correct. The Full Moon that is used isn't the 'true' full moon, which allows the date to be calculated well in advance so we can decide when to celebrate the holiday.

EASTER SUNDAY THROUGH 2029

If you want to mark your calendar for the next few years, these are the dates of Easter through 2029:

• 2025 April 20th
• 2026 April 5th
• 2027 March 28th
• 2028 April 16th
• 2029 April 1st

You can also use this algorithm to figure out the date of Easter. It might be fun to teach the kids. Click HERE to get the calculation. It's too complicated for me.