Astrosophy — The Platonic Year as the Relationship Between the Sidereal and Tropical Zodiac

Reading Time : 7 minutes

Different astrological traditions have different approaches to Astrology. Among the differences that we can find between them, the main one definitely concerns which is the “right Zodiac” to use. Some of them use the Tropical Zodiac, others the Sidereal.

In general, the dispute tends to polarize the question. The underlying premise is that if one Zodiac “works” the other must be wrong. This one-sided approach usually leads to rejecting one Zodiac in favor of the other. Or to pass from one system to the other as if it were a sort of religious conversion.

In this article we are going to take into account the communications coming from Anthroposophy—the Spiritual Science founded by Rudolf Steiner—in order to find a middle ground. Instead of rejecting one Zodiac or the other, we are going to be looking at a bigger picture in order to understand not only their differences but also where they stand.

In this sense, please note that I’m not taking a side in favor of one system. On the contrary, I invite you to take this post as a humble contribution for deepening the understanding of our cosmos, which in my opinion seems to have enough room for both the Zodiacs.

Let’s start by noting a very simple fact. We can have a direct experience of both the Zodiacs. On one hand, we can look at the stars at night. They are out there to contemplate, forming the constellations of the Sidereal Zodiac. On the other, we can observe the changes through the seasons as a direct expression of the Tropical Zodiac.

Now, a lot of issues usually come up at this point. Who established the division from one constellation to the other? How can we deal with the reversal of the seasons between the two hemispheres? These are all important questions. But for the sake of the longevity of this article we are not going to tackle them.

Instead, we are just going to observe the two systems in their simplest form to better understand them.

Differences between the Sidereal and Tropical Zodiac

What are the differences between the Tropical and the Sidereal Zodiac that we can actually observe?

The Sidereal Zodiac is something that we can actually see. In fact it consists in groups of stars, by constellations that we can recognize at night. For this reason we can say that it extends into space.

The Tropical Zodiac instead is something that we can’t see right away looking to the sky. Being this Zodiac related to the seasons, we can observe it directly only by walking through the wheel of the year, following the Sun in his annual journey. For this reason we can say that it extends not into space, but over time.

For example, the beginning of the tropical Aries coincides with the vernal point, the position of the Sun during the Spring Equinox. We can’t see the tropical sign of Aries in the sky. But we can experience the beginning of spring as the Sun goes through it.

For this reason the Tropical Zodiac is an expression of the seasons. The seasons in fact are, in astronomical terms, the result of the relationship between the position of the Earth relative to the Sun.

Since in Astrology we call both the Sun and the Earth “planets” we can say that if the Sidereal Zodiac is formed by the stars through space, the Tropical Zodiac is created by the planets over time. Specifically, the Sun and the Earth.

Another consideration we can make concerns the age of the two systems. We may say in fact that the Sidereal is “old as the stars”. Whereas the Tropical Zodiac is definitely younger. This because in order to have it we need the Sun and the Earth in the first place!

This is something we usually take for granted, but both modern Astronomy and Anthroposophy talk about the formation of the Sun and the Earth at one point in the history of the Solar System. For this reason we can say that the Tropical Zodiac is “young as the Earth”.

In Anthroposiphical terms, we say that the Tropical Zodiac formed only since the Hyperborean Epoch, when the Sun separated from the Earth. If you are not familiar with Anthroposophy, the history of the Solar System is divided in various periods and sub-periods. The Hyperborean Epoch is indeed characterized by the fundamental event of the Sun separating from the Earth.

One last thing we can say in terms of differences is that the Sidereal Zodiac is located far away in the outer space. The Tropical Zodiac instead is very close to us, to the point that it expresses itself even in the mantle of the vegetation, affecting directly the life on this planet.

In the table above you can find a brief summary of all the philosophical distinctions we made so far.

The Platonic Year
as the Relationship Between the Sidereal and Tropical Zodiac

Now that we understand the differences between the two zodiacs, how do they relate to each other? How do they communicate with each other? As we said at beginning of this article we don’t want to take sides. Instead, we want to understand the relationship between these two systems, since they are both very important.

The very first thing we can say about their relationship is that the Sidereal, being far away in outer space, contains the Solar System itself and the Tropical Zodiac inside of it. Hence, we can picture the two zodiacs in this way, having one inside of the other.

Not only the Sidereal (in blue) literally contains the Tropical (in orange), but we also know that they are not always aligned. This means that the sidereal Aries is not always aligned with the tropical Aries, and therefore neither are the other signs, respectively.

With the slow passing of the centuries, the Tropical Zodiac slides in the opposite direction along the sidereal Zodiac. This means that if tropical-Aries was at first aligned with sidereal-Aries, with the passage of time it will gradually align with sidereal-Pisces (the previous sign in the sequence). This phenomenon is called the Axial Precession or Precession of the Equinoxes, and it was well known by ancient Astrologers and Astronomers.

If we take the vernal point (0° tropical Aries, in red) as a reference, we can say that every roughly 2160 years it is going to indicate the previous sign. This means that in 25920 years (2160 x 12 signs) a full rotation is completed. Rudolf Steiner referred to this cycle with the name of Platonic Year, which is also known in Astronomy as the Great Year.

The Spiritual Meaning of the Platonic Year

The fact that the two zodiacs progressively separate from each other might lead to inconsistencies when we use one or the other. But what’s the meaning of this divergence? What’s the spiritual reason behind this phenomenon?

According to Anthroposophy, every time a sign-shift between the Zodiacs occurs, a new Cultural Epoch starts. A Cultural Epoch is a 2160 year period during which a specific spiritual impulse is given to humanity. A whole new spiritual direction is taken, carried out in particular by a specific civilization.

Here’s the list of the Cultural Epochs of the current Post-Atlantean Epoch in relation to the Sidereal constellation aligned with 0° of tropical Aries at that time:

So, basically each Cultural Epoch was the result of a new spiritual impulse that was given to humanity from the cosmos. Therefore we can now understand the reason behind this misalignment. Its function is to allow different spiritual impulses to enter the Earth. The Tropical Zodiac, and 0°Aries in particular, is the door through which these new impulses enter the Physical World.

In this sense, the Platonic Year functions like a sort of Cosmic Clock. The panel with the hours of this clock represents the Sidereal Zodiac. Whereas the Tropical Zodiac would be the clock hand, pointing a specific constellation.

But how does all this work? How does a new spiritual impulse manifest itself? Let’s now talk about the descent of these new spiritual impulses, in order to better understand also the role of the Tropical Zodiac.

The Descent of a New Spiritual Impulse

So far, we delineated three concentric spheres:

• The Sidereal Zodiac, the outermost and distant sphere. It’s the origin of the spiritual impulses that are going to bring a new Cultural Epoch;
• The Tropical Zodiac, the middle sphere. It is the gateway this impulses are going to align with in order to descend down to earth. This sphere is located between the Sun and the Earth;
• The Sphere of the Earth itself, the place where the new impulses are going to manifest through a new civilization.

We can think about this process as something that gradually descends, getting more and more “dense”. Metaphorically, it’s like a vapor, gradually becoming water, and lastly reaching the solid state of ice.

So on one hand this vapor would represent the spirit; on the other the ice would be the physical manifestation. But what about the water of our example, what about this sphere in between? In Anthroposophical terms this sphere between the spiritual and the physical is called the Soul.

These three levels of manifestation can be expressed in Anthroposophical terms into the so called three worlds:

• The Spiritual World, which corresponds to the  Sidereal Zodiac
• The Soul World, which corresponds to the Tropical Zodiac
• The Physical World, which corresponds to a third specific Zodiac

In a future article we are going to talk about the relationship between these Three Zodiacs. In this post we’ve been focusing mainly on the first two and their relationship, beautifully expressed by the archetype of the Platonic Year.

Thanks for reading, as always if you enjoyed this article please subscribe to the Astronomicon Newsletter with the bar at the top of the website to receive weekly updates and not to miss future insights on the three Zodiacs. Thanks again and have a great week.