The stars we now recognize as the constellation Ursa Major have been there for hundreds of thousands of years or longer and in exactly the positions we see them. However, humans did not specifically identify ALL of the stars we associate with this constellation until only a few hundred years ago when cartographers began to systematically partition the sky into constellations. The motion of these stars since 750 BC has not altered their location by very much. The stars themselves are 100s of million of years old and have remained pretty much the way you see them for millions of years.
Copyright 1997 Dr. Sten Odenwald
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