You may have noticed that the date of Easter Sunday changes every year:
The date of Easter Sunday is calculated using a calendar that is based both on the Sun and the Moon* and takes place “on the first Sunday after the Paschal Full Moon”. Because the Gregorian calendar is based on the Sun only, the date of Easter changes from year to year.
The Paschal Full Moon is based not on an actual astronomical event but on historical tables established by a bunch of religious guys in 325AD, and its date can be up to ± 2 days from the actual astronomical Full Moon. The Paschal Full Moon is selected as the first of the Full Moons recorded in these tables to follow the March Equinox (also known as the vernal equinox as it is the day on which the night and day are the same length when heading into Spring in the northern hemisphere and coming from the Latin ver for spring).
When a line connecting adjacent dates is drawn a pattern becomes obvious, especially when the scale is compressed.
The earliest Easter can possibly fall is March 22nd, though this is very rare, occurring most recently in 1818 and next in 2285. The next earliest date is March 23rd, as it was in 2008 and this will not happen again until 2160, by which time you will be dead.
The latest date Easter can occur is April 25th, which last occurred in 1943 and will next occur in 2038. The cycle for Easter dates repeats every 5 700 000 years exactly, and the most common date within that cycle is April 19th, occurring in 3.9% of cases. Easter moving around to the extent explained above is a real pain and in my opinion we should all just agree that from now on Easter Sunday is always the nearest Sunday to April 19th.
* Lunisolar calendars like this are used by many Jews, Buddhists, and some Hindus as well as those in Burma, China, Korea, Mongolia, Tibet and Vietnam.
Your blog stands out in that it contains practically no conjecture, conclusions, or opinion. It takes some time getting used to this, but it is a pleasant diversion.
Some of the posts have an implicit message, or leave the conclusions to the audience, like the one on technetium-99m.
“in my opinion we should all just agree that from now on Easter Sunday is always the nearest Sunday to April 19th.”
I could not understand why I had not had my birthday on Palm Sunday, the day of my actual birth. Looking at your dates I have to keep going till 95!!!
It is interesting tnat i have had my birthday on Easter Sunday a few times.
I really like the fact that Easter moves around so much. The variety makes it interesting from one year to the next. I live in the Southern hemisphere and Easter is always a fantastic time of the year with beautiful weather. i prefer later Easters as the beautiful Autumn (Fall) period is in full swing as we move from the heat of Summer. Of course it is the opposite in the North and is difficult to appreciate what it is like for those in the Northern hemisphere. Our daughter was born on Easter Sunday and it is nice to know how old she will be when her next birthday will be on Easter Sunday.
Dude, i just tried googling something related and i think you could be the guy to help :)
As the owner of a slightly overactive mind, I could not help noticing this year (2017) that we had only just enjoyed two “Four day work weeks” here in the UK and quickly on the back of it we had another “four day work week” cos May Day is the first Monday in May which we also have as public bank holiday. My brain thought i bet this doesnt happen very often at all but i cant work out just how often we get only 1 full work week between the “Easter four days weeks” and the “May Day four day week”……….reading your article im also wondering if its ever possible to have three “four day work weeks” all in a row cos of late Easter and early May Day, if so what is the frequency?
Pretty tricky to work out huh?? if you cant do it, just say ;o)
I believe 2038 will give you what you want Richard. Make sure you enjoy it though as the next one is 2190 :)
I’ve never thought of the date of Easter as a pain, you just look at the calendar. You don’t get into the reason (unless you were thinking “Paschal is self explanatory), but it is because Easter is tied to the Jewish festival of Passover, and of course the Jewish calendar is a lunar calendar. It’s an eclectic mix of Religion, the sun and the solar calendar, the moon, and the lunar calendar, pagan spring time festivals (“Easter” is name after Eostre the goddess of spring)