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Alternate Perceptions Magazine, October 2015

Archaeo-astronomical Sites in SE Colorado

by: Jeanne Gripp

Archaeo-astronomy is the study of how sky watchers of the past understood the phenomena they saw in the sky, how they used these phenomena and what role the sky played in their cultures. Often the people relied on sunlight and shadow plays striking and passing across targets and designs which were aligned with Equinox, Solstice and Cross Quarter sunrises and sunsets. The celestial cycles of the moon, Venus and Mars captivated their attention, as well. Knowing seasonal durations and transitions was vital to their success in hunting migratory prey and in the planting and harvesting of crops. Archaeoastronomy draws on several scientific disciplines: astronomy, archaeology, anthropology, psychology and epigraphy (the decoding of ancient inscriptions).

In the southeast corner of the state of Colorado are three notable archaeoastonomical sites:  Crack Cave, Sun Temple and the Pathfinder site. These unique sites are all located in the two Comanche National Grassland locations. Along with unique astronomical alignments are inscriptions usually attributed to the Old World. Let us delve further….

Crack Cave is located just north of the Colorado/Oklahoma state line. The area where it is found is called Picture Canyon, receiving this name from the abundance of petroglyphs found there. Inside one of the many crevasses that might be called a cave is an archaeo-astronomical site that is only observable on the Spring and Autumn Equinoxes. Three sets of inscriptions can also be found inside the cave. These inscriptions have been speculated to be Ogham writing. 

Ogham is the oldest form of writing in Ireland and Scotland. It can still be seen inscribed on hundreds of large and small stones, on the walls of some caves, but also on bone, ivory, bronze and silver objects. The Ogham script was especially well adapted for use on sticks. And sticks were always in ready supply and easier to carve on than rocks. The true origin of Ogham is unknown. A 7th century Irish text states that the origins of Ogham should be sought in the Near East. Ogham may have originated in Libya where it is believed that the Phoenicians came from. The Phoenicians settled many areas of Spain where the early Celts lived. The Phoenicians later expanded their journeys to include Ireland and later Scotland and England. As these skilled seamen settled in new areas, they brought their customs, knowledge and beliefs with them. The Ogham found in Europe is usually written vertically while the Ogham carvings in Colorado are written horizontally. This may be because it was easier to find long uninterrupted horizontal surfaces on the rock walls. 

The first Ogham inscriptions found inside Crack Cave is located at the back of the cave and translates to the Celtic Sun God. On the South wall the inscription reads, People of the Sun. On the north wall is the third inscription - The Sun Strikes Here on the Day of Bel (Bel is short for Belenus, the Celtic Sun God's name). This last glyph is the one illuminated at sunrise on the Equinoxes. Above this last glyph are count marks which tell how many days to the Equinox. The morning of the Equinox, all the marks are illuminated. Today, the cave opening is protected with a metal grate to prevent vandalism but the gate is opened on the equinoxes by the park rangers to allow the public to view the alignment.

Sun Temple is located to the NW of Crack Cave (about halfway to La Junta from Springfield). It consists of a small cave with the majority of its glyphs on the roof of the cave. Here is the inscription of a rare triple planetary alignment of Venus, Jupiter and Saturn that occurred within the constellation of Gemini. The words Noble Twins has been translated from the Ogham script. This alignment occurred on a cross-quarter day - August 471 AD. A cross-quarter day is one which occurs halfway between an equinox and solstice. Another archaeoastronomical alignment is here; one which only occurs at the Spring and Autumn cross quarter days. Near it are the words Season for Reaping. Because the Sun Temple wasn't discovered until 1982, the patina on the petroglyphs had been preserved. In 1987, a Prof. of Geology at Arizona State University sampled the patina or rock varnish that was embedded in the grooves of various petroglyphs. His results showed that some dated back to 2700 BC.

Rock varnish accumulates on the outside of rocks.  Rock varnish is made up of a coating of approximately 70% clay particles combined with mineral deposits of iron and manganese oxides - - all probably wind-blown material that settled on the surface of rock. Other minerals mixed into the varnish composition include hydroxides plus silica and calcium carbonate. These ingredients are cemented to the rock surface by living bacteria. The bacteria reside within and beneath the microscopic layers of varnish, and are usually absent from the exposed surfaces. Exactly how rock varnish is formed is not completely known, but one theory is that varnish formation is a means by which these microbes protect themselves in their exposed, extreme environments. Manganese oxides in rock varnish block the transmission of ultraviolet radiation. Rock varnish forms very slowly and becomes thicker and darker as it ages. Many older deposits become almost black. By closely examining and measuring the varnish coat, geologists are able to measure how long the rock's surface has been undisturbed. Radio carbon dating can be used to date the petroglyphs to give a ballpark age. The science of dating petroglyphs by using the rock varnish is still in the formative stages.

The Pathfinder site is a 40 X 12 foot slab of sandstone rock with a flat, East facing surface covered with petroglyphs. A large boulder to the East leans onto the southern half of the Pathfinder, creating a cave. The extended northern part of the Pathfinder panel is exposed to the direct sunlight at sunrise with a distinct shadow cast by the adjoining boulder. This site is located high above the Purgatoire River valley South of La Junta, Colorado. It was originally discovered in 1996. On Pathfinder's rock face, a distinct shadow is cast from an adjacent rock onto a prominent and unique target-like petroglyph indicating the potential for marking time. 

The Pathfinder site has a vast array of images. The most noticeable is the howling dog petroglyph which has an interesting stream of symbolic figures emanating from its mouth. To the south of the Dog glyph, more petroglyphs are distinguishable. Most notable is a large wing-like or sail-like image with horizontal lines. This is the equinox Target for the shadow created by the adjacent boulder to the East. The Target and the Dog glyphs are the largest and most prominent petroglyphs at Pathfinder. Below the Target are a series of petroglyphs including a human figure, abstract and representational animal glyphs.

At sunrise on the day of the equinox, the Dog glyph is illuminated by the first light. The shadow created by the adjacent boulder emerges at dawn and begins to engulf the Target. As the sun rises, the shadow edge fits the northern outline of the Target. Because of the cave-like conditions for much of the rock face, isn’t possible to observe or photograph Pathfinder in its entirety. Only by drawing details of the photos taken has the panel been re-created. At least two different styles of petroglyphs can be seen: earlier abstract characters and figures and later representational petroglyphs. There are also unique sequences of parallel lines, but they were too worn to be distinguishable. A Native American archaeo-astronomical petroglyph was also found @ Pathfinder. It is believed to be of Changing Woman, a person found in many Native Tribal Stories. Changing Woman is crossed with a dagger of light on the Equinoxes.

Who carved these intriguing images? Could it have been explorers, looking for ore to mine or new land to populate? Or might it have been nomads, simply following the herds? We may never know for certain. Many scientists feel that there should be physical evidence or artifacts to support the claim that the grooves are Ogham writing. There probably were artifacts at one time but repeated flash flooding through the centuries has washed away or covered up any artifacts that may have been there. The fact that most of the petroglyph panels are 10ft or more above the bottom level of the canyons and arroyos supports this theory of flash flooding stripping away the soils found in the bottom of the canyons. An open mind and honest academic study will be needed to properly study sites such as these to grasp a small understanding of the Peoples who visited the Americas so many centuries ago.










Lehrburger, C. Secrets of Ancient America. Rochester, VT: Bear and Company, 2015

McGlone, W. Ancient American Inscriptions. Sutton, MA: Early Sites Research Society, 1993


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