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I've been taught that since the Earth is an imperfectly balanced object, it "wobbles" like any other unbalanced spinning object. Wobbles like a top nearing the end of it's spinning. To finish a complete wobble circumference takes about 26,000 years so today's inclination (23.5 degrees) as to the sun will lessen and increase as this cycle progresses.
It is a large wobble. If one circumscribes in the sky via the axis into the heavens, the circle currently extends from near Polaris (today's pole star) to Vega (the pole star in 13,000 years).
> “I’ve been taught that since the Earth is an imperfectly balanced object, it “wobbles” like any other unbalanced spinning object.”
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Zuben, it takes 25,000 years to make one ‘wobble.’