>>41444763 (OP)
>So what calendar are they going off of?
There is the year solar cycle. Usually it is divided in 12 subunits, by most of the civs throughout human history.
There is the PRECESSION cycle.
IT IS HERE IN THE PRECESSION CYCLE THAT ALL THAT FUN FUZZ BEGINS.
by analogy to the SOLAR year cycle, ancients subdivided the PRECESSION cycle in 12 subunits.
The main point is, people don't know EXACTLY how long the PRECESSION CYCLE is. Some say it is 21k years some say it is 24k, 25k, 26l up until 36k.
Also the ancients called this precession cycle THE GREAT YEAR.
By analogy the human lifespan lasts 1 or 2 "days" in this GREAT YEAR cycle.
Ok so let's do some math:
1 "day"=66 years
66year times 365=?
66years times 360=? [By equivalence with the geometric circle]
Now if you pick the lifespan as being 71 years the calculation checks with astronomyfags know of the PRECESSION
https://en.wikipedia.org/wiki/Axial_precession
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