The integration of the solar and lunar cycles was redundantly expressed by the Chaco culture, often in relationships to key features of the Chacoan landscape. Astronomical knowledge and expression appear to have formed a unifying cosmology for the Chacoan people across the vast region of their culture. This cultural florescence was centered in Chaco Canyon, itself a topographic center in an open and spare landscape.
Research by the Solstice Project has shown that twelve of the Chacoans’ major buildings, eight in Chaco Canyon and the four largest outlying buildings, are oriented to the solar and lunar cycles (Sofaer 2007). These orientations are to the azimuths of the extremes and mid-positions of the sun and moon that are marked at the Sun Dagger site and at two other sites on Fajada Butte (Sofaer and Sinclair 1987). The inter-building alignments and the internal geometries of the Chacoans’ major buildings also express solar and lunar relationships (Sofaer 2007). The inter-building alignments form an astronomical regional pattern of approximately 5,000 square kilometers. This pattern was centered and cardinally organized at the central complex of Chaco Canyon. In addition, one of the primary Chacoan roads, the Great North Road, appears to have been built to commemorate the relationship of the central complex of Chaco Canyon to celestial north and to a badlands canyon in the north (Sofaer et al 1989).
The Chacoan people integrated their knowledge of astronomy with the use of visually prominent --- and sometimes dramatically situated--- features of the landscape. The extensive solar and lunar patterning of the Chaco architecture is symmetrically ordered and centered in the most sharply defined topography of Chaco Canyon. Pueblo Bonito and Chetro Ketl, the two largest buildings of the Chaco world, are east-west of each other: they are located at the base of the cliffs that rise most precipitously from the canyon floor. Pueblo Alto and Tsin Kletzin are north-south of each other, forming a north-south axis that divides the east west distance between PB and CK: they are located on two of the most elevated sites of the Chaco mesas. The Great North Road is an elaborate construction that runs fifty kilometers to the north from this central complex ---across an open plano--- and descends the steepest slope of a badlands canyon in the north, where above this slope a prominent feature is located. The light markings atop Fajada Butte appear also to be a cosmographic expression –their occurrence at high sites chosen perhaps for relationships to ‘the world above’.
/Members of today’s Pueblo communities, descendents of the Chacoan culture, have expressed their regard for the Sun Dagger as a sacred site, noting also its dramatically elevated location. The late Alfonso Ortiz, (anthropologist and member of the Pueblo, Ohkay Owingeh) said that the Sun Dagger site “would be one of the central concerns of their (the Chacoans’) lives and there would be people there on a regular basis praying, meditating, leaving offerings and making observations”(Solstice Project 1982). Ortiz further noted the Puebloan character of the Sun Dagger site as “a center of time on a high butte.”
As Ortiz considered photographs of the solar markings of the site in 1978, just prior to the Solstice Project’s finding of lunar markings at the site, he perceived that “where the sun is so marked so would be the moon” (Solstice Project 1982). He believed that because, he said, in the traditions of the Pueblo people the sun and the moon are held as spiritual beings who reside in complementary relationships to each other. He also noted that one or two people would be at the Sun Dagger site observing the light markings and that their observations would determine the beginning and ending of ceremonies in the canyon. These comments anticipated what research would show in the coming years
The Chacoan people in very different kinds of experiences appear to have been united in a shared attention to celestial cycles. The intimate observations of the Sun Dagger site by a few ceremonial officiants, suggested by Ortiz, is in contrast to the large public settings of the massive Chaco buildings and great kivas where probably great numbers of people participated in ritual acts related to the sun and moon. And yet while viewing the sun’s and the moon’s alignments or markings, whether at the Sun Dagger site or at a Chaco building, on a day of equinox or solstice, or a night of the lunar standstills, they were within the same experience of cosmology.
In some instances the Chacoans observing the very same astronomical phenomenon would be at sites located great distances from each other. As an example, at Chimney Rock Pueblo, a Chacoan building set on a precipice in southwestern Colorado, people would have the spectacular view of the moon rising between two pillars of rock at its most northern position in its 18.6 standstill cycle, the northern major standstill (Malville and Putnam 1989): and at that same time ceremonial officiants would see the moon’s shadow mark the large spiral petrogylph on Fajada Butte. These sites are separated by one hundred and forty kilometers.
Suggestions have been made that the dispersed Chacoan communities, located across the 800 or more square kilometers of the Chaco cultural region, were related to each other – and sometimes joined in pilgrimage to the ritual buildings of Chaco Canyon-- by a precisely timed solar and lunar calendar (Judge 2004). This calendrical knowledge was probably held as sacred -- and its details maintained secretly in esoteric contexts—to be experienced by some in small private events and by others in large scale public hierophanies.
All participants must have had some experience or perception of Chaco Canyon as a center of significant power, where cosmological knowledge was expressed most intensely. Paul Pino of Laguna of Pueblo conveys that ancestral Pueblo history may have carried such an understanding of
Chaco: “In our history they talk of things that occurred a long time ago, of people who had enormous power, spiritual power, and power over people. I think those kinds of people lived here in Chaco” (The Solstice Project 2000).