Visitors to Chaco Canyon got a treat this morning. They got to watch the fall equinox sun rise through a solar alignment built into Chaco’s great kiva, Casa Rinconada.
Chaco Canyon, a World Heritage archaeology site near Farmington, New Mexico, was built by Ancestral Puebloans in 850 CE. The city thrived for the next 400 years as the inhabitants built massive trade networks, iconic ceremonial spaces, and quite possibly maintained a record of various celestial events.
In addition to building structures to align with solar events like solstices and equinoxes, some archaeologists think various glphys found throughout the canyon represent astronomical events. For instance, a pictograph of a hand, crescent moon, and ten pointed star has been interpreted as the 1054 supernova, an event so immense its light could be seen for two weeks. A petroglyph depicting a circle from which wavy lines emanate has been interpreted as the 1097 solar eclipse and concurrent coronal mass ejections.
The heart of the Chaco Canyon complex is managed by the National Park Service (NPS) and it is NPS that arranged the fall equinox viewing. If you missed it this year, fear not. The Chaco Culture National Historical Park has an entire calendar of events and will likely host other solstice and equinox gatherings in the future.