Astrology Zodiac Wheels - © Dr Shepherd Simpson

Definition: [Principles] [Zodiacs] The term Zodiac comes from Ancient Greek "Zodiakos Kyklos" and refers to a 'circle of the animals.' Zodiac wheels have several different definitions. The history of the development of the wheels is given below.

The Ancient Babylonian Zodiac Wheels: The original zodiac wheels were bands of constellations seen in the night sky, which would rise and set as the night progressed. They were first observed by the priest-astrologers of Ancient Babylon, in the 2nd millennium BC or earlier, and were named for their Gods Enlil, Anu and Ea. Aside from their importance in astrological divination, their appearance could be used to tell the time through the night, and their heliacal risings and settings to mark the progress of the year.

The first zodiac wheel in a form recognisable to us was also seen by the Ancient Babylonians. This was the Path of the Moon through the constellations of the night sky, a Lunar Zodiac [we would now call this a Draconic Zodiac] equivalent to fifteen or sixteen of the Greek constellations plus the Pleiades. This Ancient Babylonian definition of a zodiac wheel was therefore: A circle of constellations against which a heavenly body - usually the Moon - is seen to move.

The Ancient Greek Zodiac Wheel: The Ancient Greek, Achaean, culture did not possess a zodiac wheel of the same form as the Babylonians. It is certain that they possessed no Solar Zodiac at all, and considered the Zodiac Constellations we know today to be unimportant. However, the earliest Greek works we have, those of Homer and Hesiod, show that the Achaeans were intensely interested in the stars, in fact many of their ancient constellations are those we still use to map the heavens today. Some historical astrologers, of whom I am one, are now convinced that the Achaeans did use another type of zodiac wheel, the Galactic Zodiac of constellations, in their astrology. It is notable, as mentioned above, that Zodiac is a Greek not a Babylonian word.

The Late Babylonian Zodiac Wheel [The Equal Sign Wheel]: At some time later than 550 BC the Babylonians introduced an important change to their concept of a zodiac wheel, that it should be divided into twelve equal segments approximately based on the positions of twelve Constellations. Other planets apart from the Moon also assumed an importance not seen before in their Omen Astrology. This definition of this Classical Babylonian zodiac wheel can be written as: A band of the heavens approximately 14º wide, centered on the ecliptic, against which the Moon and other planets are seen to move, as seen from the Earth. This band is divided into equal 30º segments, each one of which corresponds to one of twelve Babylonian constellations.

Unfortunately, this simplified view of the heavens has a large flaw: some constellations, notably Virgo, are in reality much bigger than the others. This fact causes considerable controversy in astrology, even today. However, we have to bear in mind that a simplified view of the heavens would have been far easier for the Babylonians to use in an age without telescopes or astrological computer programs.

When was the Late Babylonian Zodiac Wheel Introduced?The Babylonian Omen Texts show us that no Equal-Sign Zodiac was being used before about 550 BC. Individual horoscopes are not found from before 400 BC. The take up of the new Zodiac system into these new horoscopes can be seen in surviving Babylonian cuneiform tablets. In the third century BC the positions of the Moon were still given with respect to the stars. The first known use of a zodiac position for the Moon dates to 262 BC, in a cuneiform tablet from Uruk. By a century later, the star-related positions have dropped out of use, and lunar positions are only given relative to a Zodiac.

The rise of these important facets of modern astrology [the Equal-Sign Zodiac and the individual horoscope] is so sudden and their differences from the preceding Omen Astrology so great that modern astrological commentators [notably Robert Hand] have speculated that much of the astrology we know today must have been the work of one man, or one school of thought operating in Babylonia during this period. [Perhaps in Uruk; we have no Moon-position cuneiform texts outside Uruk before 150 BC.] Certainly, there was no time to make the many centuries of observations of the planets and their effects on people, which perhaps we generally assume to underlie the history of astrology - an assumption which goes back to some Classical Greek astrologers. Perhaps this shouldn't surprise us too much. The Babylonians were not modern observational scientists, but they were perfectly capable of forming rich and complex philosophical world views. However, this does mean that our astrology was never based on actual observations, but rather on ideas of how man and the universe interacted. It still remains a challenge for we astrologers today to prove that the theories yield accurate predictions.

Where in the Heavens did the Late Babylonian Zodiac Wheel Begin?: After the fall of Babylon to the Greeks in c 331 BC, cuneiform astrological tablets were transmitted by Alexander the Great's armies to the Greek world. They gave two systems for the point in the heavens at which the Babylonian Solar Zodiac began: that the Vernal Equinox lay 10º from the start of the Zodiac, [System A attributed to Nabu-rimanni, c 560 to 480 BC] or that it lay at 8º from the start of Zodiac [System B attributed to Kidinnu c 400 - 310 BC]. In other words, the Solar Zodiac started either 10º or 8º to the right of the Vernal Equinox, as viewed from the Northern Hemisphere, in the two systems.

Owing to the Movement of the Ages, 10º from the start of the Zodiac would tie to a Vernal Equinox point in about 500 BC, and 8º from the start of the Zodiac to about 375 BC. Hence, they are consistent with what these two Babylonian astrologers would have observed in the skies during the likely periods of their particular lifetimes. However, this reason for the difference in systems was not widely understood by later Greek astrologers, and both systems were used by later Classical astrologers up to Ptolemy's time, even though by then - because of the Movement of the Ages - they were both inaccurate by several degrees. Archeologists have found ephemerides [tables of planetary positions] based on both systems, dating from Classical times.

The Classical Greek Zodiac Wheel: The Classical Greek zodiac wheel is the basis of the standard Solar Zodiac wheel we use today. It is essentially the Late Babylonian zodiac wheel adopted by the Greeks in the intermingling of cultures that took place when Babylonia and many Greek isles were part of the empire of Alexander the Great and his successors.

The transition of Zodiac and Zodiac Constellations between the two cultures was not perfectly smooth. In particular, the Babylonian constellation Luhunga [LU.HUN.GA in Sumerian script], the Hired Man, [or more prosaically the Agrarian Worker] never made the transition. It was replaced by Aries, the Ram, in Greek zodiacal astrology, thought to be the ram of the Golden Fleece of Jason and the Argonauts.

Libra as a constellation also does not seem to have existed for the Greeks, rather they saw a much larger Scorpius, its claws the stars that we would call Libra today. By the second century AD Greek star maps (e.g. the Mainzer Globus) were still showing the 'Greater Scorpius' as a 'double-sign' of the Zodiac. This confusion is reflected in Ptolemy's Al Magest where he discusses the sign of Libra, but all the star names of Libra are parts of the "Claws of the Scorpion".

Furthermore, the Greek heavens contained an ancient "thirteenth" Zodiac Constellation Ophiuchus, the Serpent Bearer, which doesn't seem to have had a counterpoint in the Babylonian skies. Whilst twelve Greek constellations were co-opted for the zodiac wheel, Ophiuchus was ignored. Again this causes considerable controversy in astrology, even today.

The Sidereal Zodiac Wheel: The Sidereal Zodiac we have today is essentially as given above: the early Classical Greek rendering of the Babylonian system. This can be defined as: A band of the heavens approximately 14º wide, centered on the ecliptic, against which the all the [known] planets are seen to move, as seen from the Earth. This band is divided into equal 30º segments, each one of which corresponds to one of twelve Greek constellations. This wheel is not tied to the Vernal Equinox.

The Tropical Zodiac Wheel: In the 2nd century BC the Classical Greek astrologer Hipparchos is thought - or so we are informed by Ptolemy - to have been the first to suggest another change to the solar zodiac wheel: that the Zodiac should begin at the Vernal Equinox. [Rather than that the Zodiac should begin 10º or 8º away from the Vernal Equinox, as the fourth century BC Babylonian astrologers indicated.] This suggestion was rejected by most astrologers of the time, and it had to wait until three centuries later before Claudius Ptolemy made it part of astrological orthodoxy. However, this was more reasonable thing to do in the second century AD, as by Ptolemy's time the Vernal Equinox did actually lie very close to the start of Aries, because of the Movement of the Ages. [In fact by then it was already in Pisces: see Movement of the Vernal Equinox Point for more deatils on this.]

Previously, in Babylonian astrology, the start of the Zodiac was related to the star positions in the heavens. By stipulating that Aries should begin at the Vernal Equinox, this tied the zodiac wheel to the calendar for the first time, because we, as the Romans did, organise our calendar so that the date of the Vernal Equinox always stays the same. This then is the Tropical Zodiac of Western astrology. This zodiac wheel can be defined as: A band of the heavens approximately 14º wide, centered on the ecliptic, against which the all the [known] planets are seen to move, as seen from the Earth. This band is divided into equal 30º segments, each one of which corresponds to a fixed set of dates in the yearly calendar, with the Zodiac starting at the Vernal Equinox.

It is also, as Cyril Fagan put it in Zodiacs Old and New, Llewellyn 1950 AD, p 53, the 'greatest blunder that has ever been made in the history of astrology.' The blame for this error really lies with the astrologers of the Middle Ages, not Ptolemy. These later astrologers - rediscovering Classical astrology after it had all but died out in Europe under the influence of the Catholic church - took Ptolemy's comments on the Vernal Equinox starting Aries at face value, without realising that they were only true for a little before Ptolemy's time. In the Middle Ages, and now, because of the Movement of the Ages, the Vernal Equinox is in Pisces. Hence, unfortunately, nearly two millennia after Ptolemy, the Movement of the Ages has made this zodiac wheel hopelessly out of synchronisation with the heavens of the Greek Constellations.

Nearly all of Western astrology still uses this wheel, following the errors of the Middle Age astrologers, meaning that skeptics can, quite correctly, question one of the fundamentals of our current astrological practice.

The Vedic astrological tradition, being much less broken than astrology in the West, did not make this mistake and continued with the standard astrological practice of using a Sidereal Zodiac wheel.

The Real Solar Zodiac Wheel: The Real Solar Zodiac Wheel is based on the real constellations, without the simplifications of Late Babylonian or Greek astrology. It is defined as: The thirteen constellations against which the Sun is seen to move, as seen from the Earth.

The Planetary Zodiac Wheel: This is the Planetary Zodiac Wheel based on the real constellations, without the simplifications of Classical Babylonian or Greek astrology. It is defined as: The constellations against which the planets are seen to move, as seen from the Earth. The planets are seen against more constellations than is the Sun.