The Visitor

Follow the arc (the handle of the Big Dipper) to Arcturus. For years wešve heard that little device to find our way to one of the brightest stars in the nighttime sky. Rising above Arcturus (to the north) is the kite-shaped constellation of Bootes.

At different ages, the meaning of this constellation has changed. Over thousands of years, not only have the central thoughts of people changed, but the axis of the Earth itself has moved. The center around which the stars rotate, that special star we call the North Star, has shifted.

6000 B.C. The pole is close to the head of Bootes. Arcturus itself closer to this head. The heavens now turn around Bootes and its brightest star, Arcturus. Bootes is the Titan Atlas, supporting the world on his shoulders.

3000 B.C. Civilization is now mostly agricultural. The Big Dipper is a plow cutting through the nighttime sky, pushed by Bootes, the Plowman of the sky. The nighttime sky reflected the daytime work of the people.

1000 B.C. The Big Dipper is part of a great bear, a bear forced to remain always in the heavens, never allowed to rest in the cooling waters at the edge of the sky. Bootes is the guardian of this punishment.

2000 A.D. Arcturus is known to be passing through our Milky Way galaxy at a right angle. It will be a faint star in half a million years -- a moment in the life of a star -- and invisible after that. Not for a hundred million years will it return, tied to our galaxy by the invisible threads of gravity. Arcturus is just visiting.

When stars die in our galaxy, they enrich the interstellar medium with the heavy elements -- carbon, oxygen, iron -- that we need to live. These metals are mixed in the gas clouds out of which new stars are formed. Arcturus, formed when the Universe was young, has had no part in this process. Unlike the Sun, it contains no heavy elements. Arcturus could not even have planets, much less life.

(03/07/07)