Precession of the Equinox
Astrology as it is known today was developed between the
fourth and first centuries B.C.E. in the Mediterranean Basin. At
the beginning of the year, marked by the spring equinox, the
sun rose in the constellation Aries. After several centuries of observations,
around 125 B.C.E., a Greek astrologer named HipEncyclopedia
of Occultism & Parapsychology 5th Ed. Precession of the Equinox
parchus discovered that very gradually the sun was moving in
relation to the zodiac; that is, the precession of the equinoxes.
There is some evidence that the phenomenon had been discovered
earlier, but since Hipparchus, Western astrologers in general
were aware of it.
The precession is caused in part by the slant of the Earth.
It spins on an axis slanted at 23 degrees relative to its orbit
around the Sun. That slant immediately accounts for the seasons.
As the Earth moves around the Sun, where the axis is
pointed toward the Sun, summer occurs, and where it is inclined
away from the Sun, there is winter. However, as the
Earth spins on its axis, because it is not a perfect sphere, it also
wobbles slightly. It is this wobble that causes it to move slightly
backward each year. That movement is hardly noticeable,
being only one degree every 71 years.
Most Western astrologers use what is termed the tropical zodiac.
The beginning of the year is marked by positioning 0°
Aries at the point where the sun is located on the spring equinox.
However, that point changes slightly every year, hence the
zodiac moves slightly every year. Some astrologers use what is
termed a sidereal equinox, in which the suns true alignment
with the constellations is retained. In the sidereal zodiac, the
traditional relationship of the zodiac with the seasons of the
year is lost.
This movement is slight from year to year but over the centuries
makes a real difference. It takes approximately 2,150
years for the spring equinox to move from one sign to another
and approximately 27,000 years for the wobble to make that
point to return to its previously held position. The movement
of the Suns position at 0° Aries within one sign over a 2,100-
year period defines an astrological age. Astrologers believe that
different historical periods are ruled by different signs. In our
own day we are believed to be experiencing the transition of the
sun from the sign Pisces to Aquarius. The sign of Pisces the fish
is often associated with Christianity, of which the fish has been
a popular symbol. The contemporary revival of astrology has
seen the twentieth century as the beginning of the Aquarian
Age and has projected a hope that it will bring broad characteristic
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New York Philosophical Library, 1990.
Campion, Nicolas. The Age of Aquarius A Modern Myth.
In The Astrology of the Macrocosm. Edited by Joan Evbers. St.
Paul, Minn. Llewellyn Publications, 1990.
Filbey, John, and Peter Filbey. The Astrologers Companion.
Wellingsborough, Northampton, UK Aquarian Press, 1986.
Precession of the Equinox