Equinoxes, Solstices and Cross-Quarter Days 5.22 Hermetic Systems    

... results. These two methods are called the 'mean sun' method and the 'true sun' method. The mean sun method assumes (erroneously) that the Earth moves at ... constant speed in a circular orbit around the Sun. The true sun method calculates a cross-quarter day based on the .... Free download of Equinoxes, Solstices and Cross-Quarter Days 5.22

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