Calculating the date for Easter Sunday

Easter commemorates the resurrection of Jesus, which is believed to have occurred on the third day (inclusive) after Passover. In the Hebrew calendar, Passover occurs on the 14th day of Nisan. Nisan is the name for the first month of the Hebrew Calendar. The Hebrew calendar, is a lunisolar calendar used today for Jewish religious observance, and as an official calendar of the state of Israel. Nisan is the first month of spring in the northern hemisphere and the 14th day of Nisan corresponds to a full moon. As early as the second century many Christians had chosen to observe Easter only on a Sunday. To a first approximation, Easter is celebrated on the first Sunday after the Paschal full moon, which is the first full moon on or after March 21(a fixed approximation of the March equinox). The earliest possible date for Easter is March 22 and the latest possible date is April 25. The latest date Easter can occur is April 25th, which last occurred in 1943 and will next occur in 2038. The Catholic Church and Protestant churches (which follow the Gregorian calendar) celebrate Easter on a different date than the Eastern Orthodox Churches (which follow the Julian calendar). Easter Sunday in the year 2022 is on April 17 in the Western Churches and is on April 24 in the Eastern Churches.