Nadia asked why Orthodox Easter is on May 5th this year, which is 34 days from today, when it is Easter for everyone else. So, I went to research. It’s funny in its own right that only in Russian is every day of the year after Sabbath called Sundays in honor of Christ’s Resurrection—only one of which is the real deal. And it has its formula (see below). In all other languages, this day is called something else—sun day, week, the Lord’s day.
So, returning to Easter. Its date in the Orthodox calendar is calculated as “the first Sunday after the spring equinox (March 21st Julian) and after Jewish Passover (which is Pesach).” The latter is so that the remembrance of the Jewish exodus from Egypt precedes the commemoration of Christ’s Resurrection. But to avoid mentioning this dependency, the Orthodox calendar states “after the first full moon,” and Pesach is observed on the 15th day of the Jewish month of Nisan, which falls on the full moon.
There is a calculation algorithm by Carl Friedrich Gauss from the distant 18th century.
You have to divide the year number (in our case 2024) by 19, 4, and 7 and determine the remainders of the division. For 2024, this turns out to be—A=10, B=0, and C=1. Next, find the remainder of the division (19*A+15) by 30, which is D=25. Then, divide the sum (2*B + 4*C + 6*D + 6) by 7 and find the remainder E = 2*0+4*1+6*25+6 mod 7 = 6. Now, to calculate the date of Easter, you need to add D and E to March 22. Mar22+6d+25d=Apr22.
Next, we adjust for the Julian calendar +13 days and obtain May 5th.
Such is the mathematics, full of magic numbers.
Hi, I'm Rauf Aliev. 