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Ancient Observatory Brings Old Knowledge to New Viewers

During this year’s summer solstice, knowledge of astronomy and geometry developed by Native people thousands of years ago was put into practice.
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During this year’s summer solstice at the site of the Jeffers Petroglyphs in southwestern Minnesota, knowledge of astronomy and geometry developed by ancient Native people thousands of years ago was again put into practice.

The slow unveiling of this ancient understanding began 13 years ago when on a walk in the hills not far from the known petroglyph site, Thomas Sanders noticed a configuration of boulders that might seem random to a casual observer but sparked a question for him: Did these rocks create a petroform, a stone alignment, placed in this way, perhaps by ancient Native peoples, for a reason?

Such a question would come naturally to Sanders, an archaeologist who manages for the Minnesota Historical Society the nearby petroglyphs site, where more than 5,000 carvings that likely date from 10,000 or more years ago to as early as 150 years ago have been identified. He had seen a similar kite-shaped configuration a year earlier in a farmer’s field.

Further study would confirm that indeed this configuration of boulders, thought to be 1,000 to 3,000 years old, was constructed to mark celestial activity. It stretched 31 feet, 10 inches long and 21 feet, 4 inches wide and its makers chose pink feldspar-rich granite boulders for the creation.

This ancient “observatory” was created with an astounding mathematical and astronomical knowledge. “It’s the most accurate observatory I’ve ever seen. For every alignment, it’s dead-on,” Sanders said.

In an unpublished paper on the site, he noted that four alignments of the stones mark the sunrise and set of the yearly summer and winter solstice, two mark the fall and spring equinox and one the lunar solstice that happens every 18.6 years. “The celestial alignments found in its outline record the cyclic travels of the sun, moon, and stars,” Sanders wrote. “It is a simple yet elegant structure that succinctly and profoundly describes the observable celestial universe and its life-giving activities.”

Courtesy Minnesota Historical Society

A few people gather to view the solstice sunrise at the site of the recreated several-thousand-year-old observatory now at Jeffers Petroglyphs for viewing.

But the private location of these stones, not within the historical society lands, seemed too fragile to reveal for public viewing. Simply moving the stones would disrupt the careful configuration.

“It’s so fragile, we didn’t want anybody to even know about,” Sanders said. “We don’t want people up there, we don’t want it destroyed. It’s a miracle it survived.”

As the petroglyphs’ site manager, Sanders has regularly consulted Dakota, Lakota, Cheyenne and Arapaho elders to better understand the traditional stories connected to the collection of carvings on the stone outcrop rising from the prairie grasses. It is one of the oldest continuously used sacred sites in the world. It is believed the stone carvings of earthly animals, human figures and sky dwellers like Thunderbird were part of the ceremonies done here by the ancestors of the Ioway, Cheyenne and Dakota people and are still done today.

When Jeffers Petroglyphs became an historic site in 1999, Sanders said, elders were first consulted for the proper ceremonies and protocol to maintain it as both a place for spiritual use and public viewing. Often, areas will be restricted while people do ceremonies or prayers, he added. “These are knowledges that are protected. … activated with prayer. It’s something that needs to be done correctly.”

Courtesy Thomas Sanders

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The rock face at Jeffers Petroglyphs shown from a distance.

So after finding the stone observatory on the hill, Sanders tapped the expertise of two Dakota elders, Tom Ross and Joe Williams.

Williams, Sisseton-Wahpeton, learned about the Dakota ways since he was a small boy. His grandparents taught him cultural traditions and the teaching narratives that helped the people to remember them. “Grandma and Grandpa told a lot of stories. … I was wondering about these stories, where did they originate?”

About 25 years ago when Williams first visited the Jeffers Petroglyphs, what he saw there amazed him. “All the stories the Dakota had are written on the rock.” He saw the eagle, the bear, the bison carved there and already knew the stories and clans connected to them.

Courtesy Thomas Sanders

Dakota elder Joe Williams walks along a rock face at Jeffers Petroglyphs.

The carvings represent traditional stories, vital to maintain, but Sanders and the elders believe equally important may be spreading the word, especially among Native youth, about the vast scientific understanding of their ancestors. That desire created a dilemma with discovery of the fragile ancient observatory.

The elders felt the knowledge needed to be showcased, even if the actual stone configuration was not. “The goal of the elders is to show Native peoples that they were scientists and mathematicians and astronomers,” said Sanders. “What we decided to do was to replicate it at the Minnesota historical site here.”

So it was that this year, during the solstice, Sanders helped to create a version of the ancient stone petroform within the Jeffers Petroglyphs historical site lands to demonstrate how it indicated the solstice sun and how thousands of years ago it helped those past “scientists” prepare for the seasonal plantings, gatherings and activities necessary to survive. The stone configuration will now remain there, where people can observe it and learn about the ancient astronomical and scientific knowledge it represents within the Jeffers Petroglyphs historical site lands.

Courtesy Thomas Sanders

These carvings at Jeffers Petroglyphs, according to Site Manager Thomas Sanders, show the Ho Chunk or Winnebago people’s hero tale of Red Horn and his companions Thunderbird and Wolf defeating giants.

As for Williams, his goal, ultimately, would be to bring together elders from many Native peoples from across the continent, Alaska to Florida, to the Jeffers Petroglyphs for discussions and recording of the old wisdom from each culture. It can be inspired, he believes, by the stone carvings that show the old stories and the clan connections.

“Every image, to me, indicates all the indigenous people on this continent. To remind us who we are—the buffalo, the eagle, the fish. The symbols remind us of the culture, the education, the knowledge,” Williams said. “We’ve got to get together these people with the stories, these lost histories.”