The Mayan apocalypse may have been a bust, but a century-old understanding of the calendar that spawned the doomsday rumors appears to be right on.
In a new study, scientists used modern methods to double-check the match between the Mayan Long Count calendar and the modern European calendar. Understanding how the two coincide is important, because research on the rise and fall of the Maya suggests that climate change spelled their doom. To be certain of that link, however, researchers have to be able to match carved Maya historical records with dates in the modern calendar.
Linking the two calendars is no picnic. The Long Count calendar is essentially a cyclical count of days, known as k’in. The k’in are counted in 20-day cycles called winal or uinal, which in turn are catalogd in 360-day cycles called tuns. Twenty tuns make a 7,200-day k’atun (about 20 years), and 20 k’atuns then make a b’ak’tun.
The rest here.