Chaco’s Mission for Astronomy

Chaco’s Night Sky Initiative: Since 1991, Chaco Culture National Historical Park has offered a strong astronomy component in its public interpretive programs. Public programs emphasize the practices of the Chacoan people a thousand years ago, as well as modern approaches to viewing the same night sky they viewed–in a remote environment with clear, dark skies, free from urban light pollution.

Astronomy also provides a framework for helping to protect Park resources. Mission portrayal All Park lighting has been retrofitted to reduce light pollution and enhance night sky viewing. In 1993, the Park designated the night sky as a critical natural resource to be protected and has worked on efforts to reduce the threat of urban light pollution in the Southwest. Chaco Culture is currently partnering with the University of New Mexico to qualitatively measure the light pollution which is coming into the Park from neighboring communities.

UNWANTED LIGHT INVASION: Even from one of the darkest areas in North America there is still light pollution. Click on the image above to reveal all of the light trespass currently visible from Chaco Culture National Historical Park.


NIGHT ASSESSMENT: The CCD camera which was used to record this 90 second image of Chaco Culture’s astronomy cadre will be used to quantitatively monitor light pollution coming into the Park from surrounding communities.

The Park established an on-going partnership in 1991. Star parties have been offered twice yearly. In January 1997, brought thier astronomy equipment to Chaco. He was so impressed with the skies above Chaco that he offered to donate a domed observatory and equipment to the Park.

The Chaco Night Sky Program:  The Park began constructing a permanent observatory at the Visitor Center in 1998. In May 1998, Superintendent C. T. Wilson, John Sefick, staff, volunteers, and hundreds of visitors participated in the dedication of the Chaco Observatory. The Observatory now serves many different purposes, adding a new dimension to Chaco’s interpretation of astronomy:

The 100,000 Park visitors per year now have the opportunity to attend the educational astronomy programs, slide shows, night sky, and solar observations scheduled throughout each week.

Serious amateurs can use Chaco’s state-of-the-art Charged Coupled Device (CCD) imaging system to conduct research and image the night sky.


Amateurs can use the many telescopes available to view the very dark skies of northwestern New Mexico.

Volunteers who wish to sharpen their teaching skills can learn to present to the public basic information regarding our scientific understanding of the universe and star lore from a variety of cultural perspectives.

EVENING PROGRAMS: The Chaco Observatory is open to Park visitors during the summer on Tuesday, Thursday, Friday, and Saturday evenings. An informal program about archaeoastronomy is followed by observing, weather permitting.

NATIONAL AWARD: In 1999, the National Park Foundation awarded Chaco Culture National Historical Park and the Albuquerque Astronomical Society an Honorable Mention in the category of education at its Partnership Award Ceremony in Washington, D.C.

Ancient Connection–Modern Connections:   The Chacoan people were intimately aware of all their surroundings. They were close observers of the sky and seasonal cycles, and their observations provided them with the invaluable ability to time their agricultural and ceremonial events, which were central to their survival. Today, Puebloan descendants carry on many of these same traditions.


Visitors are drawn to the Park to learn about the monumental Chacoan sites, to view the pecked and painted images on canyon walls, to observe scattered pieces of pottery, and to ponder the greatness and meaning of the Chacoan world. It is natural to wish for a connection with the people who flourished in this stark and challenging place. The constancy of the night sky, so clear and brilliant at Chaco Canyon, is a special connection that we all can share, as we look to the stars to better understand our place on Earth.

MODERN SUN WATCHERS: Keeping with the traditions of ancient and modern Puebloan cultures, Chaco encourages the safe observation of the sun as part of its astronomy program.

It was TAAS that introduced John to Chaco Culture National Historical Park. The Park had established its Night Sky Program in 1991, so John’s suggestion of relocating his observatory into the Park was well received by Park officials. The photo shows the delivery of the dome to Chaco in March of 1998.
John donated approximately $40,000 worth of astronomical equipment to Chaco. In return, Chaco Culture, through revenue generated through its bookstore, gave approximately $50,000 for the construction of the buildings to house John’s equipment.

Construction of the Chaco Observatory began in March of 1998. A location near the Visitor Center was chosen because the site had been archaeologically compromised during the construction of the Park’s Visitor Center.

The Chaco Observatory was dedicated on May 30, 1998 and immediately began an outreach program to Park visitors. Today, nearly 10,000 people participate in its programming which includes interpretive presentations about Chacoan astronomy, tours of the night sky and explanations of deep-sky objects imaged at the Chaco Observatory. Solar observations are conducted during the day. If you are an amateur or professional astronomer who would like to volunteer, click here.