The Y2K problem became a hot topic as the year 2000 approached. It was a leap year every 400 year, and the Post and Meteorological Offices had some problems with their computers on February 29. Once, the Christian Churches had a similar problem. In the year 325, the First Council of Nicaea fixed the date of Easter as the first Sunday after the full moon following the vernal equinox and also the equinox as March 21. However, the Julian calendar was out of phase with the equinox by one day every 128 years and was 10 days behind the solar year by the 16th century. Then Pope Gregory XIII was concerned about the fact that the date of Easter, the most important feast for the Christian churches, was out of sync with the date of the actual vernal equinox, which blasphemes God. Eventually, Pope Gregory instituted the Gregorian calendar in 1582 and decreed that the day following Thursday, October 4, 1582 would be Friday, October 15, 1582. In other words, the Gregorian calendar began by skipping 10 days. From now the date of Easter will be out of sync with the solar year by one day in 3000 years, and we wonder if the Pope after 30,000 years will have the same concern.

Related calculator

[1] Easter Calendar Calculator [2] Julian and Gregorian Calnendar Calculator