What is the approximate duration of the cycle over which the vernal equinox point shifts backward through the constellations due to precession?

Answer

About 25,800 years

The point where the Sun crosses the celestial equator to begin spring slowly shifts backward through the constellations over a cycle of about 25,800 years due to precession.

What is the approximate duration of the cycle over which the vernal equinox point shifts backward through the constellations due to precession?

#Videos

The Sky Part 7: the Sun's Annual Motion - YouTube

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