How is the Golden Number connected with Easter?

Answer 1

The Golden Number is a number from 1 to 19 that indicates where within the 19-year Metonic Cycle a given year lies. Every 19 years includes almost exactly 235 lunar cycles, give or take one day depending on the number of leap years within a given 19 years. Therefore, every New Moon, Full Moon, etc. falls on the same day of the year that it did 19 years earlier, ± one day. Since every 19th year has the same Golden Number, in every year with the same Golden Number the moon phases start on the same dates, ± one day depending on the position within the leap year cycle and with a one-day adjustment for error every 220 years. Every year that is evenly divisible by 19 has the Golden Number 1. The following year has the Golden Number 2, the year after that has the Golden Number 3, and so on.

The 1582 reform of the Julian calendar authorized by Pope Gregory XIII not only removed three days from every 400 years and set New Year's Day to January 1st, but it also set the date for Easter for every year until the year 4099. The table from which the date of Easter is determined shows the date of the Paschal Full Moon, the full moon that falls during the week before Easter, for each of the 19 years of the Metonic Cycle, with adjustments every 100, 200 or 300 years. Many people believe that Easter is always the Sunday following the first full moon after the vernal equinox. While that usually turns out to be the case, that is not the rule. When the actual date of the Paschal Full Moon disagrees with the date given in the table, the date in the table is used anyway.

Some of the years that are evenly divisible by 19 and which, therefore, have a Golden Number of 1 are 1900, 1919, 1938, 1957, 1976, 1995, 2014, 2033, 2052, 2071, 2090, 2109, 2128, 2147, 2166 and 2185. (Remember, if a year has a Golden Number of 1, the previous year has a Golden Number of 19.)

Here is a list of each of the Golden Numbers, 1-19, the last year that had that Golden Number, the next year that has that Golden Number, and the corresponding Paschal Full Moon Date used for determining the date of Easter for the years 1900 through 2199 (Easter is the first Sunday after the date shown, even when the date shown is a Sunday).

1. 1995 - 2014 - April 14
2. 1996 - 2015 - April 3
3. 1997 - 2016 - March 23
4. 1998 - 2017 - April 11
5. 1999 - 2018 - March 31
6. 2000 - 2019 - April 18
7. 2001 - 2020 - April 8
8. 2002 - 2021 - March 28
9. 2003 - 2022 - April 16
10. 2004 - 2023 - April 5
11. 2005 - 2024 - March 25
12. 2006 - 2025 - April 13
13. 2007 - 2026 - April 2
14. 2008 - 2027 - March 22
15. 2009 - 2028 - April 10
16. 2010 - 2029 - March 30
17. 2011 - 2030 - April 17
18. 2012 - 2031 - April 7
19. 1994 - 2013 - March 27