We know the maya understood the cyclical routine of earth. The reason for THEIR calendar came when "UGG" realised the rumbles in the earth, the storms in the sky, the blood from the stones ( lava) were/are ALL attached to the stars, they are "written " if you will! The reason their timeline stops is probably due to the end of the mapped cycle. BUT there's been multiple cycles I think.
Sorry.. where are the facts to back up this claim, and even with the facts, how does that relate to the Earth ending in anyway - and how could someone predict that from knowing the storms in the sky (due to highly charged particles) rumbles in the earth (due to tectonic plates shifting - unrelated to storms) and due to lava flowing (volcanic eruptions caused from pressure in the earths molten core, again unrelated) and finally the stars in the sky - which are lightyears away, so far that even their gravity is nothingness on our planet.
My sources tell me :
It is likely that the Mayan calendar did not originate with the Maya, but rather originated in a previous culture and that other cultures such as the Aztec in turn also derived their calendar from similar sources.
The original purpose of devising such a calendar, with no obvious relation to any astronomical or geophysical cycle, is not known, but there are several suggested sources. A common idea is that the length of the calendar was based on multiplying 13 and 20, which were important numbers to the Maya. Twenty was the basis of the Maya counting system, and was taken from the number of human fingers and toes.
Another idea is that the 260-day period came from the length of human pregnancy. This is close to the average number of days of gestation. It is also possible that the number 260 was noted as being a repeating pattern for some combination of the above reasons. Humans are good at finding patterns even where none exist.
the Maya likely inherited the Tzolkin and perhaps the Haab from preceding cultures. These calendars were used throughout the region, and it is likely that all of the contemporaries of the Maya inherited their calendars from common or similar sources. That source is frequently identified with the Olmecs, although there is considerable debate about them as the originator of the calenders. Other potential sources are sometimes cited as the Zapotec and Mixtec cultures.
Claims of accuracy and precision are specious because they are comparing apples and oranges. The Gregorian calendar is primarily a solar calendar. The Haab was primarily a solar calendar. The Tzolkin, 'Calendar Round' and 'Long Count' calendars are not solar calendars. We will compare the modern Gregorian calendar with the Haab and see just how accurate it was.
No solar calendar ever devised can do away with some form of leap days (or "intercalary days"), for these simple reasons:
There is not an integer number of days in a year (365.2524 days per year)8
There is not an integer number lunar cycles in a year (12.3683 lunar cycles per year)9
There is not an integer number of days in a lunar cycle (29.53059 days per lunar cycle).10