The position of the stars in the “celestial sphere” from one date of a year to the same date the next year changes slightly (see Page at right Great Pyramid for Navigation), and by that slight change from year to year (because of the earth’s axial precession rate of 72 years/degree), the ancient navigators could predict where the stars would appear in the future to measure progress by ship at sea according to geometry (earth measure), knowing that a sixth of the way around the earth is equal to the radius length of the earth.
