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Easter Date Calculation:
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The calculation determines the date of Easter Sunday in the Gregorian calendar. Easter is defined as the first Sunday after the first full moon occurring on or after the vernal equinox (March 21).
The calculator uses the Anonymous Gregorian algorithm:
The algorithm involves a series of modular arithmetic operations on the input year to determine the month and day of Easter.
Details: The date of Easter affects many movable feasts in the Christian calendar and is important for liturgical planning. Many secular holidays (like Spring break) are also scheduled relative to Easter.
Tips: Enter any year between 1583 (when the Gregorian calendar was introduced) and 9999. The calculator will determine the date of Easter Sunday for that year.
Q1: Why does Easter's date change every year?
A: Easter is based on a lunisolar calendar (combining moon phases and solar year) rather than a purely solar calendar.
Q2: What's the earliest possible date for Easter?
A: March 22 (last occurred in 1818, will next occur in 2285).
Q3: What's the latest possible date for Easter?
A: April 25 (last occurred in 1943, will next occur in 2038).
Q4: Do Eastern Orthodox churches use the same calculation?
A: No, they use the Julian calendar for calculation, so their Easter often falls on a different date.
Q5: Why was this particular algorithm chosen?
A: It's a computational simplification of the astronomical rules defined by the Council of Nicaea in 325 AD.