Anna Sofaer's Solstice Project found all Chaco great houses align to astronomical events, including the 1977 Sun Dagger on Fajada Butte. Roads from the canyon ended at natural features, not settlements. A 50-year drought post-1130 CE ended great house construction, sending Ancestral Pueblo north to Mesa Verde.
Chaco great houses feature precise astronomical alignments; civilization collapsed after 50-year drought
Site mentioned
📍 Chaco Canyon
Key facts
- Anna Sofaer's Solstice Project identified astronomical alignments at all of Chaco's great houses
- In 1977, Sofaer discovered the Sun Dagger on Fajada Butte, where light passes between three sandstone slabs to illuminate a spiral petroglyph during solstices, equinoxes, and key lunar stations
- Some great houses align to the sun, others to the 18.6-year lunar major and minor standstills
- Over 200 great houses were built across the broader Chaco region
- A road system radiated from Chaco Canyon but terminated at natural features like canyon edges, the Vesa mountains, and small bodies of water
- The roads show little compaction, suggesting they were not used for regular trade or transport
- Around 1130 CE, a 50-year drought struck the American Southwest
- Chaco habitation continued in diminished form until about 1200 CE, but no new great houses were built
- A brief population surge occurred at Aztec Ruins before it too was abandoned
- Ancestral Pueblo migrated north to Mesa Verde and Hovenweep in southwestern Colorado, chosen for their reliable deep springs
Sources
Anna Sofaer, Founder of the Solstice Project | Season 2024 - PBSpbs.org
This week's guest on "Report from Santa Fe" is Anna Sofaer, Founder of the Solstice Project, discussing Chacoan astronomy.
Museum Presents Untold Stories of Chaco Canyonnewmexicoculture.org
(Anna Sofaer rediscovered the Sun Dagger in Chaco Canyon. Her non-profit Solstice Project focuses on research and education of the Chaco culture. Richard ...
Solstice Project: Homesolsticeproject.org
Anna Sofaer memorializes her time working with Robert Redford in saying “I was only one of thousands he worked with, but what Bob gave to me and Chaco is huge.
Anna Sofaer - Wikipediaen.wikipedia.org
In 1978, she founded the non-profit Solstice Project, through which she has produced a book of peer-reviewed research papers and two documentary, PBS broadcast ...
Anna Sofaer - Solstice Projectsolsticeproject.org
Anna Sofaer rediscovered the Sun Dagger site near the summit of Fajada Butte in Chaco Canyon, New. Sofaer conducted three decades of research in Chaco Canyon
Was this story useful?
Keep exploring
Every site on this page sits on the globe, and the people who research them are on the Discord.
3D Globe · Sites by country · Story Archive · Research Library · Weekly Journal · Search
AI-generated text · images from the original sources · always verify with the sources.