Easter Early this Year

Easter will be April 4th this year. Basically the formula is that Easter should fall on the first Sunday after the first full moon that comes on or after the equinox.* That always struck me as an extraordinarily pagan formula! Then someone told me it is due to the Church using a lunar calendar instead of the usual Gregorian one, and that the equinox is always judged to be March 21st [Gregorian] regardless of when it actually occurs, which can vary. With this adjustment, I've always gotten the date right if figuring it out on my own. The way the lunar calendar actually gets adjusted is too complicated for me to follow without putting more study into it than I care to do. However, if you don't go by the actual equinox, but by March 21st, I don't think you can go wrong. 

This year there is a full moon on March 28th, so this is an easy year to get right. 

*close enough, but it's more complicated than that

I'm Still Standing, Yeah, Yeah, Yeah [it's an old guy chant for me]

When I woke up this morning I realized I was using 'solstice' where I meant to say 'equinox'; so I went back and changed it now. That's a hell of a thing to work out in your sleep, but it often happens to me. 

I realized I needed to get up, no more sleep, when I then wondered if Easter would fall on the same day each year using a lunar calendar, if there wasn't the additional adjustment of always making it a Sunday. This question didn't come up in my sleep, but after I was laying there; at least I think so!

Somewhere it said that a lunar calendar* will alternate 29 days and 30 days one after the other to get close to the approximately 29.5 days from one full moon to the next. That makes 354 days instead of 365, requiring 11.25 day adjustment to bring it in line with solstices and equinoxes instead of the 0.25 days that makes a solar calendar do a leap year every 4 years.  Clearly, the 11-12 days are not added every year, thus the variation on when Rosh Hashanah, Ramadan, and Easter occur, to name a few. 

So April 4th seems to be early, does that mean we are due for an adjustment in 2022? Otherwise Easter would keep marching back towards the winter solstice in a lunar calendar. A full 29-30 days is how they do it? Easter will be on April 17th next year, whereas 354 days from April 4th is what? Actually, I'd like to take out the Sunday adjustment, and go by March 28th and April 16th, the days of the first full moon after March 21st in each year, respectively. Call them the Easter Moons, EMs. 

354 days from March 28th EM 2021 is March 17th, and 30 days from that is April 16th, the latter being EM 2022. So this does seem to be the adjustment, one full month of 30 days, maybe sometimes 29. How often?

If you think I've gone down a rabbit hole here, just try to investigate how lunar calendars officially get adjusted. It's really hard to follow, at least from what I have found on the internet. And I may be wrong, but it seems you can't say "I'm going to buy me a doggone lunar calendar and hang it on the wall and go by that". Such things are surely possible, but as far as I can tell, they aren't available. Amazon sells a "Lunar 2021 Wall Calendar" but as far as I can tell, it's a Gregorian calendar with images and phases of the moon featured, it provides a sample page, 


Also, from what I can determine, the main Christian choice for lunar calendar is actually the Hebrew calendar, but to try to buy a wall calendar, it's the same Gregorian calendar again with holidays marked. One seems to be notebook style by week as something different, is all. 


So, I think I'll stop going down the hole while I can still breathe ... anybody who knows more about it can chime in and tell me I've got something wrong and maybe I'll change my mind. 


*evidently to call it 'lunisolar' is more correct if an attempt is made eventually to align with solar periods

I'm Still Standing, Yeah, Yeah, Yeah [it's an old guy chant for me]

well, I said I wasn't going any deeper into the rabbit hole, but I was wondering when and how Passover and Easter differ if Easter was never changed to make it an upcoming Sunday. I think I have to surrender again though. I found a chart that compares this, see link, but the very first entry, 2001, has something I'm unclear about.  According to date and time dot com, the full moon was on April 7th in 2001. The entry, though, has both Passover and Full Moon as April 8th. Wondering about this, I was able to confirm that the full moon is always on the same date all around the world, "The peak of the Full Moon is when the Moon is opposite the Sun – 180 degrees away. Therefore the Full Moon occurs at the same time, regardless of where you are located on Earth.", and that Passover "always begins on the 15th day of the Hebrew month of Nisan. Because the Hebrew months are pegged directly to the lunar cycle, the 15th day of Nisan is always a full moon."* 

So why April 8th in 2001? The answer to that is not easily found. It's not because the astrnomicial full moon can be on a different date in Jerusalem, as we found, though that can be true of the astronomical equinox. I think it might be related to the practice of always using March 21st as the equinox. In other words, lunar calendars used by religions have some fudges like that. But I am not sure yet and will have to decide if I will pursue it. *sigh*

https://en.wikipedia.org/wiki/Template:Table_of_dates_of_Easter

* the text in quotation marks comes readily from google searches

I'm Still Standing, Yeah, Yeah, Yeah [it's an old guy chant for me]

hooboy, that chart has errors. actually google had the error, corrected if you go to the link

rabbit hole, rabbit hole, rabbit hole

Xtians love Easter, they get really
excited nailing Jesus back up on
that cross every year. Leave the
man alone, hasn't he suffered
enough? Such a ghoulish holiday.

Bob, it is interesting that the symbol of the Cross, which the Romans wanted to inspire fear and terror, has been transformed into the opposite for Christians.

Getting back to the question about Easter/Passover dates, same or not?

I've decided it doesn't matter if the date of a religious calendar's full moon is not quite the same as Astronomical Full Moon unless it explains why unadjusted Easter is different from Passover. By 'unadjusted' I mean not changed to an upcoming Sunday. So I took the information from the link and reset it to show [possibly adjusted] Full Moon, then Passover, then unadjusted Easter.  

https://en.wikipedia.org/wiki/Template:Table_of_dates_of_Easter

again, Full Moon, then Passover, then unadjusted Easter

2001     April 8     April 8    April 8
2002     March 28     March 28     March 28
2003     April 16     April 17     April 16
2004     April 5     April 6     April 5
2005     March 25     April 24     March 25
2006     April 13     April 16     April 13
2007     April 2     April 3     April 2
2008     March 21     April 20     March 21  


Stopping here,  2005 and 2008 are interesting, I had to check each thing to be sure of my facts, so each following thing has been double-checked. Taking 2008, this year had the astro-equinox on March 20th [in Jerusalem too] and the full moon on March 21st. Since March 21st [Gregorian] is always used as the equinox for Easter in most denominations, that would make March 21st unadjusted Easter. It was actually observed on Sunday March 23rd. Passover in April 2008 is a full month after the equinox, this would seem to be because of the way the lunar calendar was adjusted that year, something that is complicated. And unfortunate if you are someone not rooting for a late holiday. 

Staying with 2008, the chart claims Astronomical Easter would be April 27th, unadjusted for upcoming Sunday that would make it the 20th also, same as Passover, very late. According to the footnote, "Astronomical Easter is the first Sunday after the astronomical full moon after the astronomical March equinox as measured at the meridian of Jerusalem". However, that makes no sense to me if "after,after" means what it should. Equinox March 20th, full moon 21st, works for March 21st unadjusted Easter, no? Seems to me the 'month later' business might come when the astro-equinox is after the full moon, not before it, as happens potentially when astro-E is the 22nd. But yet it is a fact that Passover was a month after the equinox that year, 2008. Well, that's answering my question "is unadjusted Easter always the same or nearly the same as Passover?"

Link for Gregorian calendar showing Hebrew calendar dates, if interested. 

https://www.timeanddate.com/calendar/monthly.html?year=2008&month=4&country=34

Quote: odiousgambit

Bob, it is interesting that the symbol of the Cross, which the Romans wanted to inspire fear and terror, has been transformed into the opposite for Christians.

For me the whole thing is macabre.
Every time I see a crucifix it bothers
me that they're celebrating torture
and death. They can deny it all they
like, but you do not use a killing
device to send a positive message.
A man hanging in the throes of
death is depressing, not uplifting.

trivia question arising from the rabbit hole:

the definition of an equinox is that time when day and night are equal in length, true or false?

Quote: odiousgambit

trivia question arising from the rabbit hole:

the definition of an equinox is that time when day and night are equal in length, true or false?

Move near the equator where day
and night are 12 hours 365.. I
never thought about it but the
equator only goes thru SA and
Africa. The rest of it is ocean. I
know a guy who lives on it in
SA and loves it. Nice weather
year round.

Quote: Evenbob

Move near the equator where day
and night are 12 hours 365.. I
never thought about it but the
equator only goes thru SA and
Africa. The rest of it is ocean.

It goes through Indonesia. Singapore is only 85 miles from the equator so it pretty much has the same pattern. You would hate it there.