NASA Logo, National Aeronautics and Space Administration

Sun-Earth Day Presents: Ancient Observatories, Timeless Knowledge

Technology Through Time: Issue #14, Chaco Canyon

The first thing one notices about Chaco Canyon and neighboring Native American sites throughout the southwest, is the dryness of the climate. Yet those who lived here grew crops with enough bounty to feed tens of thousands. Because the growing season is so brief, and book-ended by long months with little or no rainfall, agriculture must have been a major undertaking which took advantage of all the clues provided by Nature as to when to plant crops. It is perhaps not surprising that so many religious and ceremonial dwellings have some type of solar alignment literally built into their architecture. What better way to keep track of the seasons, and to keep a calendar updated, than to watch for a sunrise or sunset on certain special days of the year. The sun also played a major role in most Native American religious practices.

Many buildings and monuments have been identified throughout Chaco Canyon and the larger Southwest Region, which offer special solar events. Pueblo Bonito's special corner windows let sunlight through, but only as time marches onwards to the winter or summer solstice. At Casa Rinconada, a window on the south wall lets a beam of light shine into a niche on the back wall at the time of the summer solstice. And then there's Fajada Bute with its dazzling Sun Dagger. During each of the equinoxes and solstices, one or sometimes two, thin slivers of light trace a complicated light show across a spiral petroglyph.

We may never know for certain just how these solar events were used. There also remains some controversy about their exact details and the actual intent of their creators. But we can at least admire their creators for what must have been a sophisticated understanding of the sun's movements. We can also admire them for their cleverness in applying this knowledge to enhance their own survival in a, largely, unforgiving environment.



Image Gallery:

chaco canyon gallery image chaco canyon gallery image chaco canyon gallery image canyon gallery image chaco canyon gallery image chaco canyon gallery image

Photo Credit:

Troy Cline

Traditions of the Sun

This new experiential Web site lets you explore Chaco Canyon, learning about NASA research on the Sun and Native American solar practices within a larger historical and cultural context.

Chaco Canyon Website Launches

Exploratorium launches new site featuring Chaco Canyon's ancient connections to cyclic and seasonal patterns of the sun, moon, and stars.

Related Chaco Canyon Links