Fred Seward writes (via FFC):
The attached jpg picture [from Wikipedia] shows the precession of the pole with dates labelled. The circles of declination are spaced every 15 deg. In 176 years the pole will travel 1 deg away from the N star, or 5 deg in 880 yr. This corresponds to 1120 AD.This is true if your alignment is on the N star. If it is on the autumnal equinox, the geometry is more complicated. In this case, 5 deg will take you back to 1600. probably earlier for the vernal.
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