Photo by Alejandro Sanchez de Miguel / CC BY-SA
By Chad Woodward
Astrology is well-known as the "study of the stars," yet most people have no idea that stars don’t typically play a central role in modern astrology, except for one. The Sun is the most well-known star in astrology, most notably because even people who dismiss astrology or know very little about it still know their Sun sign. Some modern astrologers utilize "fixed stars" when reading charts, especially bright ones such as Regulus, Sirius, or Spica. However, the vast majority of astrologers prioritize planets (and many non-planetary objects such as asteroids or even non-physical objects like the lunar nodes) when reading charts.
Astrology plays a significant role in popular culture due to the ubiquity of Sun sign horoscopes in major newspapers, magazines, and now throughout the internet and social media. While the popularity of Sun signs has helped boost astrology’s visibility, it’s also led to some misconceptions. Many people think that the zodiac signs are the literal zodiacal constellations made of stars, but that's not technically true. When most people refer to their sign (sometimes referred to as a “star sign”) they're referring to the placement of the Sun in the tropical zodiac on the day of their birth. In actuality, there is more than one zodiac, and the vast majority of astrologers are not talking about constellations when they refer to planets in specific signs. While the tropical zodiac predominates in modern western astrology and popular culture, two other zodiacs exist and they played a significant role in the development of both western and eastern astrology.
All three zodiacs, including the tropical zodiac, align with the ecliptic (the path the Sun appears to move along throughout the year). However, the tropical zodiac signs do not line up exactly with the constellations they were named after. In other words, the tropical sign of Aries does not match up with the constellation of Aries. Tropical signs and constellations are two separate things. If your Sun sign is Aries, the Sun was not in the constellation of Aries at your birth. It was technically in the constellation of Pisces. Does that mean that every Aries is really a Pisces? No.
Despite what some scientists and astronomers occasionally claim in the media or written publications, your Sun sign in the modern western astrological tradition has no relationship to the constellations. And astrologers are well aware of this. Also, there is no 13th Sun sign, only a 13th constellation (Ophiuchus), but as you now know, that has no relation to the zodiac used by most western astrologers. Your Sun sign is based on the tropical zodiac, not the constellations.
There are twelve tropical zodiac signs used by the majority of western astrologers, and each tropical sign is comprised of exactly thirty degrees. However, the constellations vary in size. Virgo, the largest constellation along the ecliptic, covers forty-seven degrees of the sky, while the constellation of Cancer covers only fifteen (Lash, 50, 1999). In the tropical zodiac, there is no such size variation between the signs.
So how did this happen? At one point, early astrologers used the constellations. Yet, the astrology utilized by the first western astrologers differed significantly from the way it was conceived later on. The use of astrology as a topological view of human personality is mostly a modern conception influenced by psychology and Western individualism. The earliest western astrologers weren't using astrology to understand character traits, or even an individual's fate or destiny. The names and images from the constellational zodiac were not developed to describe human nature.
Western astrology began roughly 4,000 years ago in the area of modern Iraq. In the ancient world, this region was known as Mesopotamia, which lay inside the fertile crescent (an area not as fertile today due to several millennia of agriculture and climate change). Mesopotamian astrologers used astrology to record omens on small clay tablets. They were primarily interested in the correlation of celestial and mundane events, such as the occurrence of an eclipse and the death of a king (Rochberg-Halton, 1988, 94).
Early Mesopotamian astrology was mostly concerned with events impacting large populations and regions (Brennan,2017, 2). So, aside from the king, individuals were not the initial focus. And without the ability to accurately predict celestial events, this omen-based astrology centered around the documentation of events during or after their occurrence (Holden, 1996, 3). Mesopotamian astrologers exclusively used the constellations along the ecliptic until the fifth century BCE when twelve equal signs of thirty-degree increments came into use (Rochberg, 2004, 130). Also, around this same time, evidence of horoscopes created for individuals began to show up (Rochberg, 2004, 3).
The Mesopotamian zodiac with twelve equal signs is known as the sidereal zodiac and is still in use today, mainly in eastern traditions (or by western astrologers utilizing it). The sidereal zodiac roughly aligns with the constellations but does not precisely correspond to the constellations because the sidereal signs are equal in size while the constellations are not. The tropical zodiac widely used by western astrologers today (which is the basis for an individual's tropical Sun sign), was developed during the Hellenistic period in ancient Egypt and Greece around the latter part of the second century and early first century BCE.
In this diagram, note the size difference of Virgo, Cancer, and Scorpio in the constellational zodiac (outer wheel) compared to the sidereal and tropical zodiac signs (middle and inner wheels respectively). The constellation boundaries are significantly variable and uneven when compared to the standardized zodiacs that developed later on. Also note how the tropical zodiac is constructed by the equinoxes and solstices while the sidereal zodiac roughly aligns with the constellations but has notable overlap.
The tropical zodiac is constructed from the locations of the equinox and solstice points. For example, in the tropical zodiac, the sign of Aries begins at the vernal equinox which initiates spring in the northern hemisphere. Each sign is then constructed by thirty-degree increments starting from the vernal/spring equinox. The other three cardinal signs align with the solstices and equinoxes. The tropical sign of Cancer begins at the summer solstice, the tropical sign of Libra begins at the autumnal equinox, and the tropical sign of Capricorn begins at the winter solstice.
The equinox and solstice points gradually shift backward through the constellational zodiac due to a phenomenon known as the precession of the equinoxes. Put simply, this precession results from the Earth's wobble along its axis as it orbits the Sun. Thus, in the tropical system, the first degree of Aries shifts backward through the constellations so that today it falls in the constellation of Pisces instead of Aries. This backward shift occurs at a rate of one degree roughly every 72 years. The symbolism of the tropical zodiac draws heavily upon the seasonal rhythm rather than the ecliptic constellations despite assimilating their names and images.
During the Hellenistic era, however, the tropical and sidereal zodiacs roughly corresponded with one another, and their symbolism influenced the meaning of the signs in each system (Brennan, 2017, 217). The discovery of precession did not occur until around the second century BCE. It even then was not widely recognized by astrologers for several centuries after that (Jones, 1989, 29). It took time for the tropical zodiac to gain more widespread use among astrologers, but once it did, it solved a problem that precession eventually brought about: the gradual movement of the constellations and sidereal signs relative to the equinoxes and solstices.
There is still debate in both academic and astrological communities over the historical development and usage of these systems in the ancient world. The Hellenistic tradition of astrology that developed in Greece and later in the Roman Empire evolved more complexity to which modern western astrology is heavily based. The correspondence, or rulership, of certain planets and tropical zodiac signs, developed out of the Hellenistic astrological tradition and it works strictly within the framework of the tropical zodiac.
The seasonal symbolism inherent to the tropical zodiac is obvious. The initiatory and catalyzing qualities of cardinal signs Aries, Cancer, Libra, and Capricorn emerge from their initiation of a new season. The stabilizing qualities of fixed signs Taurus, Leo, Scorpio, and Aquarius result from their static position between seasons. And the association of versatility and instability with the mutable signs, Gemini, Virgo, Sagittarius, and Pisces are related to their transitional position from one season to the next.
The origin of the tropical zodiac and its deviation from the constellations is pretty clear. The zodiac of modern western astrology is, for the most part, starless, with the exception of the Sun and the fixed stars that are occasionally used. Of course, the tropical signs are transposed over the stars and constellations along the ecliptic, and thus everyone's tropical Sun sign is placed among them. However, the meaning of your tropical Sun sign stems from the meaning derived from the tropical zodiac and its complex interaction with seasonal symbolism, the sidereal zodiac, and the names derived from the constellations.
Which Zodiac is Correct?
The confusion over the three zodiacs and their association with astrology often spark debate in the general public, scientific and academic communities, and among astrologers themselves. It's important to realize that the premise of astrology, that celestial events correlate with Earth-based events is agreed upon no matter what branch of astrology a person comes. It doesn't matter which zodiac system one uses, the planets or other placements are typically the same. One exception to this is when using a heliocentric (Sun-centered) as opposed to the geocentric (Earth-centered) model. There are valid reasons for using the geocentric model in astrology (since astrology uses perspective as a metaphor), but that is a discussion beyond the scope of this article.
From a geocentric perspective, when a planet appears to turn retrograde, an eclipse occurs, or several planets conjoin in the sky, they do so in either zodiac system in the same place in the sky. The difference is in the naming or designation of that portion of the sky. The Sun signs that most people refer to in western society draw their symbolism from the tropical zodiac. The meaning given to those signs represents the intersection of seasonal symbolism from the northern latitudes as well as the system of rulerships born out the Hellenistic tradition of astrology.
For example, in the western, tropical system, the planet Saturn has rulership of Capricorn and Aquarius, and that planet is said to be empowered in being in those signs. Saturn's relationship to other planets or its interaction with the horizon in a chart is the same in either a sidereal or tropical zodiac. The method of assessing the strength and weakness of certain planets based on the placement of planets or objects in a particular zodiac sign differs between the tropical and sidereal.
Some astrologers subscribe to the fundamentalist view that one zodiac is more correct or superior to another. There are proponents of the sidereal zodiac who feel that because the sidereal zodiac aligns more closely with the constellations, it's more aligned with astrology's original foundations. Yet, while the sidereal signs do roughly correspond to the constellations, they don't precisely because sidereal signs are still divided by precise thirty-degree increments while the constellations are not. In the sidereal zodiac, half of Libra falls in the constellation of Virgo, and portions of other signs overlap with more than one constellation.
As a western astrologer, I use the tropical zodiac, and I find that it works within the context of that system. I don't believe the tropical zodiac to be superior or more correct than sidereal, or even the constellational zodiac. The zodiac is simply a way of placing celestial objects in specific positions and tracking their relationships and movements through time. Each zodiac, like the different house systems, reflects different ways of looking at essentially the same thing. For me, the differences between various branches of astrology reflect different perspectives and neither one is more superior or more valid than another.
Even within the context of the tropical zodiac, there is wide variation in the application of that information. A birth chart can be used to assess topical life events, personality characteristics, psychological disposition, or even the purpose or destiny a person is meant to carry out. There are also significant differences between a chart cast for a person, event, or object. Astrology is all about perspective, and I think that diversity within and between cultures should be embraced.
The idea that a system of knowledge should be homogenized and static suggests that there is only one way to understand reality. If astrology can teach us anything, it's that the truth can be understood from multiple points of view and there are many ways to arrive at it. An individual's horoscope is not a proclamation of a static and unchanging fate and destiny, and even if such a thing exists, I don't believe astrology can give a definitive picture of it.
As a tool of divination, astrology operates as an oracle that works on the basis of acausal or synchronistic principles. No matter which zodiac or paradigm an astrologer (or anyone) uses to interpret a chart, there will be wide variation in the encoded information. And there will be variation in how that information is decoded by the person receiving the information. In my perspective, astrology's goal is not to espouse some strict view of who a person is or might become, but to inspire in them the ability to engage in their lives co-creatively and to realize that their lives are a part of a much vaster and interconnected whole.
Sources
Brennan, Chris. Hellenistic Astrology: The Study of Fate and Fortune. Denver: Amor Fati Publications, 2017.
Holden, James Herschel. A History of Horoscopic Astrology: From the Babylonian Period to the Modern Age. Tempe: American Federation of Astrologers, 1996.
Jones, Prudence. “Celestial and Terrestrial Orientation: The Origins of House Division in Ancient Cosmology.” In: History and Astrology: Clio and Urania Confer, ed. Annabella Kitson. London: Unwin, 1989.
Lash, John. Quest for the Zodiac: The Cosmic Code Beyond Astrology. Loughborough: Thoth Publications, 1999.
Rochberg-Halton, Francesca. Aspects of Babylonian Celestial Divination: The Lunar Eclipse Tablets of Enuma Anu Enlil. Horn: Berger, 1988.
Rochberg, Francesca. The Heavenly Writing: Divination, Horoscopy, and Astronomy in Mesopotamian Culture. Cambridge: Cambridge University Press, 2004.