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Saturday, November 15, 2025

Why December 24, Not December 21?

The astronomical truth about the 2012 cycle completion

⚠️

Most Sources Are Off By 3 Days

You may have heard that the Maya Long Count completed on December 21, 2012. With the astronomically-verified correlation, it's actually December 24, 2012.

Standard GMT (584,283)

December 21, 2012

= 13.0.0.0.0

✗ Not verified by astronomy
✗ Based on colonial documents
✓ More widely known
✓ Winter solstice (better media story)

Astronomical GMT+3 (584,286)

December 24, 2012

= 13.0.0.0.0

✓ Verified by solar eclipse
✓ Verified by lunar observations
✓ Latest academic research (2012)
✓ Observable astronomy

The Astronomical Evidence

1. Santa Elena Poco Uinic Eclipse (790 CE)

A Maya monument records a solar eclipse on the Long Count date 9.17.19.13.16. Astronomical calculations confirm a total solar eclipse visible in the Maya region on July 16, 790 CE.

Maya Date: 9.17.19.13.16
Correlation 584,286 → July 16, 790 CE ✓
Correlation 584,283 → July 13, 790 CE ✗

2. Quirigua Lunar Records

Maya inscriptions at Quirigua record when the moon "arrived" (first became visible as a crescent). These observations match correlation 584,286, not 584,283.

3. Martin & Skidmore Research (2012)

Epigraphers Simon Martin and Joel Skidmore published comprehensive research demonstrating the astronomical superiority of correlation 584,286 in their paper "Exploring the 584286 Correlation between the Maya and European Calendars".

What This Means For You

Your Tzolk'in day sign will be 3 days different from most online calculators.

This is not an error - it's the natural consequence of using different correlation constants. We believe the astronomically-verified correlation is more accurate.

Sources & References

This calendar is built on rigorous academic research and contemporary Maya knowledge

Academic Research

  • Martin, S. & Skidmore, J. (2012). "Exploring the 584286 Correlation between the Maya and European Calendars"
  • Tedlock, B. (1982). "Time and the Highland Maya"
  • Aveni, A. (1980). "Skywatchers of Ancient Mexico"
  • Sharer, R. & Traxler, L. (2006). "The Ancient Maya" (6th ed.)
  • Schele, L. & Freidel, D. (1990). "A Forest of Kings"
  • Lamb, W. (2024). "The Maya Calendar: A Book of Months"

Contemporary Maya Voices

  • Roberto Poz Pérez (K'iche' Maya Daykeeper)
  • Hermelinda Sapon Pu (K'iche' Maya Daykeeper)
  • Komon Tohil (Organization of Daykeepers, Zunil, Guatemala)

"This is a LIVING tradition. The Maya calendar is actively used today by millions of Maya people in Guatemala, Belize, Mexico, and Honduras."

Cultural Respect & Acknowledgment

This calendar was built with deep respect for Maya culture and contemporary Maya communities. We center Maya voices, credit all sources, and acknowledge that the Maya calendar is a living tradition, not an ancient artifact. We do not claim authority on Maya spiritual practices - for authentic day sign interpretation and ceremonial guidance, please consult Maya daykeepers.