Skip to content

What is the Zodiac?


The zodiac can be understood in two ways: as a symbolic calendar based on the Earth’s movement around the Sun (the tropical zodiac), or as a map of stars (the sidereal zodiac).

To draw the zodiac, people used a circle - it's the ecliptic, the Sun’s apparent path around the Earth. When you, for example, look out the window - it seems that the Sun moves in a circle. That circle is the ecliptic.


The Tropical Zodiac

This system was made to measure the seasons. Here, the ecliptic is divided into 12 equal parts of 30 degrees, just like 12 months of 30 days.

In this strange zodiacal calendar, the new year always starts around March 21st, on the day of the spring equinox. Astrologers say it is also a beginning of the Aries sign, or "the season of Aries".

When you say, “I’m an Aries,” it only means that you were born in the first 30 days of spring - not that the Sun was in the Aries constellation. Libra? the first 30 days of Autumn.

And that’s basically it. It’s a way of fortunetelling based on the season and month of birth.

Image by: me.

The tropical zodiac has nothing to do with the constellations that share its names. When you look at the night sky or use a stargazing app, you’ll see the planets in different constellations than astrology claims.

Why?

Because of precession. Let's talk about it. It is a movement of the Earth that makes it point to a slightly different place in space every year. It's a bit like shooting a movie of the sky and moving the camera to a different point in the cosmos every year, but in this case, the whole earth is spinning, not just the camera. Because of this, it looks like the stars in the sky are… moving backwards.

Then, against the background of these stars, we observe the Sun and the rest of the celestial bodies.

Two thousand years ago, when the tropical zodiac has been created, at the spring equinox, the Sun was truly in Aries.

Today, it’s in Pisces.

In about 250 years, it will rise in Aquarius - the famous "Age of Aquarius".

Then it will move to Capricorn, and later to Sagittarius.

This process can’t be stopped - it’s simply how the sky works.

Yet Western astrology will still say:

"Spring? Aries begins, just like every year!" 🐑😎

The ancient Greeks, from whom we inherited astrology in the West, knew about precession, but they decided to not apply it to the tropical zodiac.

It was supposed to be a mathematical, fixed construct from then, that allows us to calculate the actual inclination of the Earth in relation to the Sun and the seasons that are the result of this Earth-Sun relationship. These two objects, the Sun and the earth, is all we need to calculate the tropical zodiac. Stars are irrelevant to the creation of the tropical zodiac.

So, the tropical zodiac is an independent system from the real constellations.

But who knows, maybe the Earth's tilt and the amount of sunlight that reaches us during the seasons really do mean something.

Anyway, as long as the Earth revolves around the Sun at a constant speed, the tropical zodiac will never change. Ever.


Homonyms were accidentally created when the tropical zodiac was designed: in the tropical zodiac, "Aries" means just the beginning of spring, while in astronomy it refers to a constellation, a cluster of stars. The same is about all signs and constellations.

Most people confuse the two because of newspaper horoscopes. They use the tropical calendar - just check your birth date and read your "sign". It was simple and convenient.

No one noticed the mismatch: during the day we can’t see the stars, and at night there’s no Sun. We cannot know easly its real position.

And today, we rarely look at the stars anyway - we prefer our phone screens and TikTok.

In theory, we could come up with completely new names for the tropical zodiac signs so that they wouldn’t be confused with the constellations and would form an independent system. But astrologers probably haven’t thought of that yet.


The Sidereal Zodiac

There’s another kind of zodiac - much older than the tropical one, and actually the original system, developed by the Babylonians long before the Greek tropical zodiac. It’s called the sidereal zodiac.

The ancient Greeks, and then us, could use it, but the Greeks and modern astrologers simply decided that it was unfashionable. No, really. There is no 100% sure why ancient astrologers switched from the sidereal zodiac to the tropical one.

Sidereal zodiac doesn't measure time in the way the tropical zodiac does. It is more like a star map.

It also divides the ecliptic into twelve sectors, but based on the stars. It roughly reflects the real constellations in the sky and shows which constellation the Sun appeared in at a given time.

The sidereal zodiac is moving, following the actual motion of the sky and the precession. It must be adjusted and recalculated regularly to stay aligned with the stars.

As a result, the order of the signs is different, closer to what is happening in the sky (remember? Spring equinox in Pisces, not Aries!), and it is still moving backwards. So, there’s a high chance that your zodiac sign here will be shifted one sign backward compared to the tropical zodiac.

Today, sidereal zodiac is mainly used in Vedic astrology, where it’s the default system. But I want to point it: it is a default system for Vedic astrology, but the sidereal zodiac ≠ Vedic astrology automatically. Some Western astrologers also use it - for example, in Western Sidereal Astrology school, started by Cyril Fagan. This system is for everyone.


The choice of zodiac is one of the biggest controversies in modern astrology. Arguments over which system is "real" - tropical or sidereal - can turn into full-on astro-wars. The only thing worse is probably discussions about choosing a house system.

The fact is, many people are shocked to learn that the tropical zodiac isn’t based on the stars at all 😱

Still, some people say the tropical one is the truth. Others insist the sidereal zodiac reflects reality better.

In the end, the choice of zodiac sign and which team of astrologers you will find yourself in is up to you.


🌍 Here you can check your tropical birth chart, the position of the Sun is your "main" sign: Tropical

✨ Here you can explore your sidereal chart: Sidereal