Easter is in April this year and was in March last year. Have you ever wondered why Easter changes every year and is not on a set Sunday? Well, here is your answer.

Each year Easter falls on the first Sunday after the first full moon after the first day of spring. Since spring arrived on March 20 and the first full moon after spring arrived on Tuesday, April 15, that would make Sunday, April 20 as the first Sunday after those two events.

Historically it was back in the year 325 AD that Christian church leaders established the astronomical requirements that we still use today. Based on those requirements, Easter could fall anytime from March 22 through April 25.

In early times, there was some question of this formula simply because of different calendars that were used. In 1582 the much improved Gregorian Calendar was established which became the norm in Europe and most of the world.

So now you know why!

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