Why does the starry sky rotate, but the North Star is stationary?

The fact is that the rotation of the Earth around its axis is accompanied by the rotation of the axis itself (as the axis of a slowing spinning top begins to rotate). This effect is called precession. The precession cycle is about 28,000 years and is also known as the Platonic Year.

That is, a fixed point in the starry sky also moves in a circle, but very slowly. A similar fixed point in the sky of the southern hemisphere is not so lucky and there are no bright stars nearby. For primitive navigation, the Southern Cross constellation is usually used.

Whenever you look at the night sky, the North Star will show you the way to the north

However, this was not always the case.

14 thousand years ago, its place was occupied by the star Vega from the constellation Lyra, and it will take it again in 13,727.

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