Question:
I've heard that since the zodiac was created, the stars have shifted ever so slightly... and now the zodiac that astrologers use is no longer accurate. I heard that you're now the sign before the sign you think you are. Is that right?
Answer:
What you've discovered is called the "Precession of the Zodiac" or the "Precession of the Equinoxes." Yes... the positions of the fixed stars and constellations have, indeed, slowly changed their positions in our sky over the past 2,300 (or so) years. Yet, Western Tropical Astrologers haven't chosen to "adjust" the "Tropical Zodiac" with the always changing positions of the stars. Western Tropical Astrology is the system of astrology most Westerners are familiar with via daily horoscope columns. The reason behind this seemingly stubborn refusal of most Western astrologers to "change with the times" is that Tropical Astrology is not based on planets passing through the celestial constellations. Western Tropical (tropos - turning) Astrology is, and has always been, based on the turning of the seasons (spring, summer, autumn, and winter). And yes... there is another zodiac, the "Sidereal Zodiac," that astronomers, Vedic Astrologers (originating out of India), and a few Western Sidereal Astrologers use; and the Sidereal Zodiac is loosely based on the planets passing through the celestial constellations.

Tropical Zodiac vs Sidereal Zodiac
If one were born on the 29th of March, using the traditional Tropical Zodiac, your birth Sun is located in 9 degrees of Aries. However, if one were to use the Sidereal Zodiac - then your birth Sun would be located in 15 degrees of Pisces. The current discrepancy between the two zodiacs is approximately 24 degrees and is not quite an entire sign, since each of the 12 zodiac signs is assigned 30 degrees (12 X 30 = 360). So, if one were to use the Sidereal Zodiac in their calculations, it wouldn't always equal out to being the sign before. For example: My birth chart Sun is positioned in the late degrees of its zodiac sign. So regardless of whether I choose to use either the Tropical Zodiac or the Sidereal Zodiac, the zodiac sign for my late degree Sun would still end up being located in the same sign.


Here's the Bottom Line
While the "Precession of the Equinoxes," is important to Tropical Astrology in respect to an astrological concept called the "Astrological Ages," (which I'll be discussing in an upcoming feature) - the precession is not relevant to the practice of Tropical Astrology. Tropical Astrology (and the Tropical Zodiac) have always been based on the path of the Sun traversing the Earth (the ecliptic) in relation to the turning of the seasons. Western Tropical Astrology lays no claim to being based on the positions of the Fixed Stars and constellations in the sky.

Short History Lesson
Around 300 BC, when the spring and autumn equinoxes (i.e. the seasons) were originally positioned by the Greeks on the path of the Sun traveling around the Earth (the ecliptic) - it was done by the Greeks for the purposes of setting up a solar calendar. For simplicity sake, in setting up the calendar, the 12 sectors of the Sun's path (the ecliptic) were artificially divided up into 12 equal sized sections. Each sector had 30 degrees and was named for the zodiac constellation the Sun was "more or less" passing through. I say "more or less," because it was realized that the 12 constellations located on the Sun's path were all of differing sizes and shapes. So the Sun always spends unequal amounts of time passing through each of the 12 zodiac signs. For example: The Sun spends only 19 days traveling through the smaller constellation of Cancer and spends 45 days traversing the sign of Virgo. At the time this was done, the Sun's position approximately corresponded to the visual perception of its location against the 12 zodiac constellations in the sky. And so, the point of 0 degrees Aries was established as being when the Sun passed over the vernal (spring) equinox point, and the corresponding point of 0 degrees Libra was established as being when the Sun passed over the autumn equinox point.

The Greeks appeared not to know about the precession prior to 2nd century BC. So, for some historians, it was commonly believed that this "precession" was first discovered about 150 years later (around 150 BC), when it was noticed that there was a slight displacement of the Fixed Stars and constellations. This displacement was then named the "Precession of the Zodiac" or the "Precession of the Equinoxes." However, according to astronomer Dr Percy Seymour ("The Birth of Christ; Exploding the Myth"), based on new discoveries, it is now generally accepted that ancient Egyptians, as early as 4000 BC, were already aware of the precession and that it had even been incorporated into their religion.



History Lesson Over
Even after 2,300 years, Western Tropical Astrology continues to be based on the path of the Sun traversing the Earth in relation to the turning of seasons. The Tropical Zodiac has admirably withstood the test of time; and so most Western astrologers continue to use the Tropical Zodiac. They continue to use it for one simple reason. It works. Therefore (for Tropical astrologers) the exact point where the Sun passes over the vernal (spring) equinox is still calculated as being 0 degrees of Aries.

Sidereal Zodiac?
As mentioned earlier - astronomers, Vedic Astrologers, and a few Western Sidereal Astrologers use the Sidereal Zodiac, which is loosely based on planets passing through the current positions of the fixed stars. I qualify this by saying "loosely," because (as also mentioned previously) even the idea of each zodiac sign having 30 degrees was (and is) an artificial division of the the Sun's path through the 12 constellations. If one truly wished to be more "reality based" on the positions of the constellations, then Virgo would then need to be assigned her full 45 degrees, rather than her measly apportionment of 30 degrees. Of course... the other smaller zodiac signs, such as Cancer, would then have to give up some of their precious territory. Further, using the Sidereal Zodiac (and its arbitrary setting of 0 degrees of Aries) is inexactly based on where the constellation of Aries might begin. The good news is that in another mere 23,500 years (or so) - both zodiacs (Tropical and Sidereal) will once again be in agreement, and we astrologers will be left with nothing else to bicker about...