Cradle of Constellations

The source:“The Origin of the Greek Constellations” by Bradley E. Schaefer, in Scientific American, Nov. ­2006.

Whoever looked up at the seven moderately bright stars scattered across the ancient sky in the shape of a dipper and named them the Great Bear may have been the world’s first great communicator. Whoever it was certainly lived a long time ago. Even though the seven stars look nothing like a bear, writes Bradley E. Schaefer, a Louisiana State University physicist and astronomer, that’s what they were called by ­long-­ago people as dispersed as the Greeks and the Zuni, the Basques and the Hebrews, the Cherokee and the Siberians. All knew versions of the myth of the Great Bear, that the four stars in the bowl of the dipper represent the bear, perpetually being chased by the three stars in the handle, representing hunters. It is virtually impossible that cultures in so many parts of the world would have thought up the story indepen­dently, Schaefer says. That means the Great Bear was named at least 14,000 years ago, when there was a land bridge across the Bering Strait that allowed some ancient group to carry the idea to the ­Americas.

Constellations are among humankind’s earliest creations and can be more revealing in some ways than the pottery and tools unearthed by archaeologists, offering a glimpse of what ancient people considered important enough to inscribe in the heavens. Through a process called preces­­sion, constellations can even help in dating art and clay or stone tablets. Because the earth wobbles on its axis, the positions of the stars change over the centuries. The positions of the constellations described in ancient poems or depicted in art have been used to date such artifacts to within about 80 years of their ­creation.

The oldest known constel­lations are all named for gods, animals, and farm imple­ments. The se­quence of titles changes over time, Schaefer says, moving from religious to folk to practical to scientific. The Great Bear constel­lation may have grown out of early relig­ious practice. European cave paintings, artifacts, and ensembles of cave bear skulls date to more than 30,000 years ago and suggest some kind of bear worship. The constel­lation may have been a folk depiction of an image used by ancient priests or medicine men. Schaefer believes that the Great Bear is quite likely one of humanity’s oldest ­inventions.