Easter is late this year as it occurs this Sunday, April 21. Last year Easter was early falling on Sunday, April 1. Have you ever wondered why it changes every year and isn’t on a set Sunday? Well, here is your answer.

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 will be today (April 19), that would make this Sunday, April 21, 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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