Baker Aerial Archaeology's Chaco Project

Return to Mysteries of Chaco | Return to Table of Site Contents


For over a decade Baker Aerial Archaeology has been locating and photographing the vestiges of the ancient Chaco world, which can still be seen from the air throughout Four Corners area of the American Southwest. We hope our observations and photographs will help shed some light on the enigmas of Chaco culture, such as the purpose of Chaco roads and such mysterious features as the large circular imprints (so-called "aureolas") that can be seen near some Chaco outlier towns in aerial views (see photo below).

In future updates of this newsletter, different aspects of aerial investigations of Chaco culture will be presented, with photographs such as the one below.

Photo: "Lee's Circle," a Chaco "Outlier" with Aureola (ca. 1100 AD)

To List of all photos on this website

Explanation of Aureola Photo:

(One of the great things about the World Wide Web is that we are now able to get photos like this out before the interested public. This image is part of a collection that Tom Baker is making for eventual publication in a book about the aerial archaeology of the American Southwest. Others will be featured here in updates of the website).

In May of 1992 we were flying our photo aircraft over the Navajo Indian reservation between Gallup, New Mexico and the Hopi Mesas of Arizona when Lee Baker, piloting the aircraft, spotted this circular imprint on the desert floor. A closer look confirmed that it was a Chaco "greathouse" ruin with an associated "aureola," as these mysterious circles have come to be called by Chaco researchers. The greathouse is the faint square imprint at the upper left part of the circle.

To give a sense of the scale: the straight, light-colored lines across the circle are automobile tracks. The larger road running from left to right is a two lane unpaved road, and a modern homestead (house and outbuildings) may be seen in the upper right, with its driveway leading out to the road.

Aureolas: Celestial Observatories?

What might an aureola be? No one can say, of course, and there hasn't even been much speculation, at least in print. The question appears to baffle everyone. Adhering to the archaeologist's penchant for calling everything that he can't explain "ceremonial," we could speculate that an aureola was an avenue for ceremonial processions, or footraces (today some Pueblo tribes do stage ceremonial races, but not on circular courses. Perhaps their ancestors did it differently).
A better guess, or at least a more likely possibility, in our opinion, is that an aureola is what remains of a prehistoric astronomical observatory, a "woodhenge" of sorts, for regulating a calendar, similar to the so-called "medicine wheels" of the Great Plains (which are circles and lines of stones that show consistent astronomical alignments). Chaco society was, after all, based on agriculture, and the timing of agricultural activities would have been all-important to it. Several such observatories scattered about the region (as aureolas in fact are) could have regulated the crop growing cycles of the ancient Chaco world.

If this was the case, we can envision the resident astronomer-priest in his observatory (the "greathouse") adjacent to the aureola, daily watching the sun, moon and stars rise and set over posts set upright in the great ring, with his runners ready to take to the Chaco roads to broadcast his pronouncements of the arrivals of important dates. Careful excavation of an aureola (and no one has ever done it, to our knowledge) might uncover evidence of sighting posts like those once set into a similar ring at the great mound city of Cahokia in the American Midwest (Illinois), a culture roughly contemporary with Chaco. The Cahokia ring, which has been reconstructed (with a center pole and posts set upright around the ring) has also been called a calendar. The Maya to the south of Chaco country had very sophisticated astronomical observatories that were important to daily Maya life, as demonstrated in their books and stone carvings.

In future Newsletter updates, Tom Baker will develop this aureola/observatory idea further, illustrating it with more aerial photos of Chaco aureolas.

Write us at <> if you have your own ideas on the subject. With enough response we could start a discussion on this page.

Also on this page in upcoming Newsletter issues: Chaco Roads (with photos), and: "Where Does Chaco's Great North Road Go?" (with photos)

Return to Mysteries of Chaco Page | Return to Table of Site Contents