Determining the Date of Easter

April 2025  :  Francine Jackson

Happy Easter, for all who celebrate it! Once more, it is coming, and at quite a late time in the month. It seems this feast is very movable; it can come anywhere from mid March to late April.

Several centuries ago, based on a slight flaw in the calendar introduced by Julius Caesar, Easter, and the days that went with it – Ash Wednesday, Palm Sunday – were coming much too early in the year. To remedy this, Pope Gregory XIII in 1582 tweaked the calendar just enough to bring the days back to where they were supposed to be.

The celebration of Easter occurs on the first Sunday after the first Full Moon after the first day of the season of spring. This year, as spring began Thursday, March 20th, the first Full Moon after that date takes place Saturday, April 12th. But, wait! The next day, April 13th, isn’t Easter, but Palm Sunday. What we have to remember is that celestial events occur based on Universal time, the time at the Greenwich Observatory. On your calendar the Moon is listed as happening at 8:22 P.M., DST. At the Greenwich Observatory, that translates to twenty minutes after midnight, April 13th. Therefore, for us, April 13th is Palm Sunday, and Easter is the following Sunday, April 20th. Next year, the Full Pink Moon will occur the first of April, and Easter will be much earlier, April 5th.