Over a period of about 26,000 years, the Earth’s axis traces out a huge circle on the sky, and over time it points toward bright stars other than Polaris, as shown on the inset on our map. This means that the axis of the Earth does not always point at Polaris. It turns out that the Earth wobbles slightly as it spins through space, just as a spinning toy top wobbles as it slows down. On a cosmic time scale, different stars take turns as our North Star. These six circumpolar constellations perpetually chase one another around Polaris.
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