Read on Twitter
Happy Thursday, friends. Today we get 21 more minutes of daylight. Two more minutes than yesterday, and 21 more minutes than December 21.
Tomorrow marks the beginning of a "new year." But what is a year? What does it even mean? Why was it invented? Is it arbitrary? Who cares?
First, our ancestors in Africa, Asia, Indigenous folks in modern day America, South America, etc. knew for many millennia that it took about 365-ish days for Earth to fully orbit the sun.
But there are a few hours, in addition to those 365 days, that have the ability to upend religious customs, social life, scheduling & trade over the course of a few centuries. With the growth of empires (war & colonialism), a wider means of time consistency was desired.
"Time" might be arbitrary, but the sun is not arbitrary. The length of the day is not arbitrary. The amount of time it takes for Earth to make a full orbit around the sun is not arbitrary. Therefore, all calendars are somehow based on our relationship to the sun.
While the Gregorian calendar is most widely observed, there have been many calendars in existence. Different cultures & religions have designed their own methods of measuring how much time has passed from varying reference points (usually religious) & the true length of a year.
The earliest resemblance to our current calendar was the Roman calendar. It had 10 months, March-December, and 38-40 random days in between because not much happened after the winter equinox and before the Spring equinox.
There were a few revisions to this calendar, then Julius Caesar instituted calendar reform and we got the Julian calendar.
Now, the Julian calendar was pretty good. It is still observed by some institutions today. It was adopted widely by the Roman Empire, and then subsequently Europe and their colonies for nearly two millennia. It was 12 months long & calculated the year as being 365.25 days long.
To account for Earth drifting & adding time onto its orbit, the Julian calendar added a leap year every 3 years. However, they over-corrected. This over-correction was problematic for The Catholic Church, who ran the world back then. (They're still powerful but not the same way.)
The math is extremely complex and it would take 1,000 tweets to explain the astronomy. In simpler terms, this over-correction meant that over the course of 1,500 years, the spring equinox was now about 10 days off from March 21. The Catholic Church sought to fix this. But why?
Why did the Catholic Church refine it down to 365.2425 (365 days, 5 hours, 49 minutes, and 12 seconds)? The answer is Easter, which automatically includes Passover.
What is Passover? Passover is the liberation of the children of Israel from slavery in ancient Egypt. Christians know this as the Book of Exodus. Hebrew literature dictates that Passover occurs at the top of spring, period. It has a relationship to the barley harvest.
We know that Easter, for Catholics & Protestants, commemorates Jesus resurrection. The last supper, in which Jesus said his body was bread & his blood was wine, was during a Passover meal. (I am not Christian or Jewish. I do not have a position on this. Please don't attack me.)
But anyway, if Hebrew literature says Passover is in Spring, we know that Easter would never be celebrated before March 21. Remember the over-correction that resulted in Spring equinox falling in early March? We now have an accuracy problem.
Easter is celebrated on the first Sunday after the Paschal Full Moon. The Paschal Full Moon occurs 13 days after Spring Equinox's Ecclesiastical moon, which usually falls on or 1-3 days after March 21.
The solar year & lunar month have a relationship, but the drift that gives us leaps years must also be accounted for on the lunar side of the house. (By the way, the Hebrew calendar had accounted for this.)
That is why Easter is not on the same day each year. Anyway, the unevenness of Earth's orbiting time is not a big deal over a couple years. However, it becomes a problem after a millennia. Suddenly, Easter fell before March 21. Correction of the Julian calendar was now underway.
Welcome to Gregorian Reform.
A council was convened, and in 1545 Pope Paul III began the process to fix the Julian calendar to restore Easter's date to accurately coincide with the Paschal moon. It took 4 decades of mathematics, physics, astronomy, fighting, death threats, etc., but it finally happened.
Pope Gregory XIII issued papal bull Inter gravissamas on February 24, 1582, officially publishing what we use today: the Gregorian calendar. Catholic nations immediately adopted the calendar.
There was just one small problem. The new calendar required everybody to skip 10 days. Imagine a bill being passed and then tomorrow is January 10. Folks were like, "............What?"
Most of the world (the British, lol) was like, "No. Go away. We'll find another solution." And continued with the Julian calendar. This meant Easter had different dates for different countries for nearly 200 years.
It took 400 years for most of the world to adopt the Gregorian calendar. Some places still use the Julian calendar or their own cultural calendar.
So, there is the history behind our calendar. It is a combination of math, astronomy, religious observances, different approaches to historical literature, a lot of fighting, and our social lives. But ultimately, it comes down to the Earth, the sun, and the moon.
It's been thousands of years, and we are still ruled by the Earth, the Sun, and the Moon. We are not in charge.
