Ecliptic

If the earth didn't rotate, and the atmosphere didn't scatter the light of the sun and obscure our view of the stars during the day, then as the earth moved slowly on its annual cycle around the sun we would see the sun moving slowly against the stars, completing a circuit around the celestial sphere once every year. This apparent path of the sun through the stars is known as the ecliptic.

Because the earth does rotate, the celestial sphere appears to spin around once every day. During each twenty-four-hour period, as it moves around with the stars, the sun progresses along the ecliptic by approximately one degree. If it were not for the atmosphere, we would see it by day among the stars. To many human communities it is important to know where among the stars the sun is. The zodiac familiar to people in the modern Western world—a band of twelve constellations through which the ecliptic runs—has its origins in ancient Babylonia. But many different "zodiacs" are possible, as for example among the Maya. The Lakota people of North Dakota traditionally keep their seasonal movement around the landscape in tune with the path of the sun through their own "zodiacal" constellations. See also:

Lakota Sacred Geography.

Celestial Sphere; Obliquity of the Ecliptic.

References and further reading

Aveni, Anthony F. Skywatchers, 49-55, 200-205. Austin: University of Texas Press, 2001.

Goodman, Ronald. Lakota Star Knowledge: Studies in Lakota Stellar Theology. Rosebud, SD: Sinte Gleska College, 1990. McCready, Stuart, ed. The Discovery of Time, 70-73. Naperville, IL: Sourcebooks, 2001.

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