TLDR: Researchers solved the Mayan 819-day count mystery by finding that 20 cycles of it align with the planets' recurring positions in the sky over a 45-year p

TLDR: Researchers solved the Mayan 819-day count mystery by finding that 20 cycles of it align with the planets' recurring positions in the sky over a 45-year period, connecting it to the general Maya calendar, the Tzolk'in.