The 13th Zodiac Sign: Ophiuchus the Serpent-Bearer?
Image source: NASA
Like clockwork, every 1.5 to two years or so someone out there brings back the rumor that there is a 13th zodiac sign and that the zodiac has “changed” and maybe you aren’t the sign you always thought you were and… blah blah blah.
This is a MYTH that stems from a fundamental misunderstanding of what astrology is.
The reason why this myth resurfaces every couple of years is unclear, as we are clearly not “discovering” a 13th constellation every couple of years. Humans have been aware of the constellation Ophiuchus at least since Babylonian times, though they had a different name for it. The word “Ophiuchus” comes from the Ancient Greek word meaning “serpent-bearer.”
The most important thing to know here is that zodiac signs are not the same thing as the stars or constellations. We typically think of astrology as relating to the stars, but in reality, tropical astrology, the astrology that most of us in the Western world know, has little to nothing to do with constellations.
Let’s talk about it.
Phoebe Buffay basically singing about Ophiuchus
What is the zodiac?
Constellations are groups of stars that, when looked at from our position here on Earth, appear to form shapes. In all likelihood, the stars within what we call a “constellation” are not actually related to one another at all. Human beings are just creative and like to find patterns in what may actually be random. That’s how we created the constellations. We found shapes in the night sky and gave them names.
On the other hand, the “zodiac” is a band of sky around the Earth’s ecliptic that is divided into 12 equal, seemingly arbitrary 30º segments that we call “zodiac signs.” Thousands of years ago, Babylonians named each of those 12 segments after the constellations that they were somewhat close to, and that is where we get the 12 zodiac signs.
So while there are 13 constellations along the ecliptic, including Ophiuchus, for whatever reason Ophiuchus was never considered a zodiac sign and still is not today.
Tropical Zodiac vs Sidereal Zodiac
The tropical zodiac aligns with the seasons of the Earth, while the sidereal zodiac accounts for the precession of the equinoxes and aligns with certain fixed stars. However, neither the tropical nor sidereal zodiac actually aligns perfectly with the constellations. These are the primary differences between the tropical zodiac and the sidereal zodiac, and neither one includes Ophiuchus as a zodiac sign.
As seen in the graphic below, the constellations vary wildly in size, each taking up anywhere from 6.5º to 44º of the Earth’s ecliptic. But in both the tropical zodiac and the sidereal zodiac, the ecliptic is divided up into 30º equal segments. Neither division of the zodiac aligns perfectly with the constellations because again, zodiac signs are not the same thing as constellations. Plenty of astrologers do use fixed stars in their work, but for the most part, astrology is not rooted in looking for patterns in stars, nor studying the relationship between the stars and the planets. At the most basic level, astrology simply studies celestial bodies (such as the planets, sun, moon, asteroids, etc.) as they move through the Earth’s ecliptic and the 12 imaginary segments—or signs—we have divided the ecliptic into.
The tropical zodiac (inner ring) vs the sidereal zodiac (center ring) vs the actual sizes of the constellations (outer ring)
In conclusion, while there are technically 13 constellations, there are NOT 13 zodiac signs, and your zodiac sign certainly did not change. We’ve known about Ophiuchus for at least 3,000 years. It just isn’t used in astrology.