(NEXSTAR) – Have you ever noticed that Easter never falls on one day? Christmas is always December 25, and Mother’s Day is the second Sunday in May. But you always have to check the calendar for Easter. Why?
Easter, if you are not acquainted, is a Christian holiday that celebrates the resurrection of Jesus. It always falls on a Sunday in March or April. To understand why, you need to look at the sky.
“The date of Easter is determined by the month. Easter always falls on the first Sunday after the first full moon after the vernal equinox, ”said Kim Mandelkow, director of the Milwaukee Archdiocese’s Worship Office.
This year, for example, the first full moon after the vernal equinox (also known as the first day of spring, which is March 20) falls on Saturday, April 16th. Easter Sunday is the next day.
“The moon is not ordinary,” said Father Martin Schlag, professor and chair of Catholic public opinion at St. Thomas University in Minnesota, explains. “He doesn’t follow the solar calendar, but he has his own lunar calendar, which changes every year.”
If the first full moon fell on a Sunday, Easter Sunday would be postponed for a week, Mandelkov explains.
Since Easter depends on the vernal equinox, it can fall anywhere from March 22 to April 25. However, Easter on any of these days is relatively rare, according to data from the U.S. Census Bureau. You will most likely see the year of Easter, which falls on March 31 or April 16, which is most often claimed for the holiday.
Next year Easter will be the same: April 9.