The wheel was constructed by Plains Indians between 300-800 years ago,
and has been used and maintained by various groups since then.
The central cairn is the oldest part,
with excavations showing it extends below the wheel and has been buried
by wind-blown dust.
It may have supported a central pole.
The star alignments are most accurate for around 1200 AD, since slight
changes in the Earth’s orbit have caused perturbations since.
The solstice alignments remain accurate today.
The Bighorn wheel is part of a much larger complex of interrelated
archeological sites that represent 7000 years of Native American adaptation
to and use of the alpine landscape that surrounds Medicine Mountain.
Numerous contemporary American Indian traditional use
ceremonial staging areas, medicinal and ceremonial plant gathering areas, sweat
lodge sites, altars offering locales and fasting (vision quest) enclosures, can
be found nearby. Ethnohistoric, ethnographic, and archeological evidence
demonstrates that the Medicine Wheel and the surrounding landscape constitute one
of the most important and well preserved ancient Native American sacred site
complexes in North America.
Between 70 and 150 wheels have been
identified in South Dakota, Wyoming, Montana, Alberta, and Saskatchewan.
In 1974, an archaeoastronomer named Jack Eddy visited this Medicine Wheel and
studied its alignments, that is, its arrangements of rocks, cairns, and
spokes. He found the arrangements point to the rising and setting places of
the Sun at summer solstice, as well as the rising places of Aldebaran in
Taurus, Rigel in Orion, and Sirius in Canis Major — all bright, important
stars associated with the Solstice. Later another astronomer, Jack
Robinson, found a cairn pair that
marked the bright star Fomalhaut’s rising point with the Sun
28 days before solstice.
Sighting from cairn E through the center hub (which may have supported
a pole) marks the summer solstice sunrise.
Sighting from C through the center marked the equivalent solstice sunset.
Standing at cairn F, one could sight the once-yearly dawn,
risings of the key stars
Aldebaran, Rigel, and Sirius, which play symbolic roles in an ancient
Cheyenne Massaum ceremony
and are also important stars in the sacred Lakota circle constellation
The dawn or heliacal rising of a star is important because it pinpoints
a date exactly. This is the day a star is first seen, just before dawn,
after it has been behind the Sun for an entire season.
From about 1200 AD to 1700 AD, these 4 stars would have acted as
solstice markers for the Native Americans -
Fomalhaut (F to D) would rise 28 days before the Summer Solstice,
Aldebaran (F to A) would rise during the 2 days just before
Rigel (F to B) would rise 28 days after the solstice,
and Sirius (F to C) 28 days after that,
at the end of August and hence marking the end
of summer and time to leave the mountain.
For more details on the astronomical alignments, see
- Banner by Troy Cline, GSFC.
- Medicine Wheel sunset photograph by Tom Melham.
- Keyhole video developed by Professor Philip Scherrer.
Keyhole2 PRO, movie maker, data importer, and high sppeed printer
modules provided thanks to Jack Veenstra and Dennis Reinhardt of
- Medicine Wheel color photo by
Richard Collier, Wyoming State Historic Preservation Office.
Used with permission.
- Cairn and prayer offerings photos by Deborah Scherrer.
- Map and photographic views by
Steven Dutch, Natural and Applied Sciences, University of Wisconsin – Green Bay
- Satellite photo from TerraServer USA
- From original diagram by Jack Eddy
- Alignment diagram copyright (c) 2002
and Moncur Gallery. All