The next dates the builders waited for
Solstices, equinoxes and zenith passage days for Chaco Canyon and the Yucatán, with exact times and a live countdown to the next one.
March equinox
2027-03-20 · 20:24 UTC
December solstice
Southernmost sunrise: 119.5° at Chaco, 115.2° at Chichén Itzá. The shortest day north of the equator.
March equinox
Sunrise due east everywhere. Watch the light serpent on El Castillo and the sunrise inside the Seven Dolls doorway.
Zenith passage · Chichén Itzá
At 20.68° N the noon Sun is overhead and upright posts cast no shadow.
June solstice
Northernmost sunrise: 60.5° at Chaco. The Sun Dagger crosses the spiral’s centre around this date.
Zenith passage · Chichén Itzá
The second overhead Sun of the year in the northern Yucatán.
September equinox
Sunrise due east again. El Castillo’s serpent returns for several afternoons either side.
December solstice
The Sun turns north again. Pueblo traditions mark this turning with ceremony.
March equinox
The cycle begins again.
See the sky the way they did
Open a viewer, pick a date and watch the sunrise point move along a real horizon. Then download the guides and take them outside.