03PrecessionSeasons

Now, to return to the point about the "Vernal" and "Autumnal" Equinox (or three days of equal duration day and night) being the earth's "perihelion" points in its orbit around the sun: earth's orbit is not perfectly circular, but occurs in an elipse, with the sun off-centre in one of the two focal "loci" centroids of the elipse. So, when earth experiences "equal days and equal nights" it means the earth is at the two points when it begins to be and ends being closest to the sun. Between these points, the earth is nearer to or farther away from the sun, and these points are called "Aphelion." The Equinoxes are therefore associated with "Caput" and "Cauda" Draconis, as the "head" and "tail" respectively of Draco.

Now, just as earth is sometimes nearer, others farther from, the sun, so too is the sun sometimes closer and sometimes farther from galactic core, as the sun our star is pulled around along our leg of the Milky Way. Just as the seasons of the north or south hemisphere ice age cycles change over the many hundreds of Aeons, so too does the sun's pole reverse once every many million millions of years. So, in the diagram above, one should think of each of the eliptical positions of earth's orbit of the sun as representing one "season" of Aeons in the sun's revolution around galactic core.