Astronomy and Space


Was Polaris always the North Star?

Earth has had several North Stars. Earth slowly wobbles on its axis as it spins. This motion is called precession. Earth traces a circle in the sky over a period of 26,000 years. In Pharaonic times the North Star was Thuban; today it is Polaris; around 14,000 C.E. it will be Vega.


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