D is for Decan
D is for Decan (or Decante) Each Astrological sign takes up 30 degrees of the wheel: 30 degrees x 12 signs = 360 degrees - a full circle Additionally, each sign is divided into 3 sub-divisions, a 10 degree segment of each sign. These are the decans. There is a first, second, and third Decan of each sign, giving more insight into the operation of that sign's energy depending on if it is the beginning, middle, or end of that sign.
The First Decan, 0 - 9 degrees As a planet moves through a sign, it enters at the first decan (0 to 9 degrees) and the "beginning" or start-up energy of that sign. The first Decan of a sign is very "Cardinal" in nature - it is bold, innovative, "excited" to start the new journey in this sign's energy. It is like when you first move into a new house or start a new job - you want to "show off" a bit and so you might exaggerate the expression of this "new self" that you have discovered. If you wish to relate the three divisions of decans to the moon cycle, you can think of the first Decan of a sign as the New Moon and Crescent Waxing phase - or the "Maiden/Child" energy of that sign.
The Second Decan, 10 -19 degrees. As a planet moves through the second decan of a sign (10 to 19 degrees), it is more settled in the energy of that sign. It has found a sense of how it operates here, and it begins to exude a more "Fixed" energy. I think of this as similar to after the newness of the new job or home has passed . . . you are comfortable with what you are doing, secure; not trying as hard to prove yourself to others because you know you belong here and have a stable confidence in how you go about your expression. In a moon cycle, this Second Decan could be related to the middle of the moon phase - Waxing Gibbous, Full Moon, and Waning Gibbous - or the "Mother/Provider" energy of that sign.
The Third Decan, 20 - 29 degrees As a planet moves through the third decan of a sign, it is carrying with it the lessons of the first and second decan, and begins preparation to move into the next sign. It carries the wisdom of all it has learned to express as it journeyed through a sign, but begins to have a more "Mutable" view in thinking about how it will carry these lessons forward into the next sign. This is like a period of time when you know your time in your home or job is coming to an end. You are training your underlings, wrapping up your affairs, or beginning to make preparations to move to whatever is calling you next. In a moon cycle comparison, you could compare this third decan to the Balsamic Waning and Dark Moon Phases - or the "Crone/Teacher" energy of that sign.
A Note on Cusps People who are born near the final degrees of a sign or the first few degrees of a sign might say they were "born on the cusp" of two signs. This is true, and there is a different energy signature at the very beginning or very end of a sign. But it does not mean that your Sun is "in both signs" or "has the energy of both signs". Someone born on the Cusp may feel like they don't fully relate to descriptions of their Sun sign... but look and see the energy signature of the First and Third Decan to understand why you might feel this way. Your sun has either "just arrived" in this sign, or it is wrapping up and preparing to leave this sign. You likely have other planets in one sign or another that are adding to your identification with one sign or another, or aspects to other planets in other signs that are influencing your energy expression. I just say this to clarify that if you are born with your sun on a Cusp, it does not mean your "sun is in both signs", but to take the Decan of the Sun into account as well as other planets in your chart.
Decan Planetary Rulerships Beyond understanding the Decans as "beginning, middle, and end" of each sign, each Decan is also assigned a Ruling Planet. These planets are seen as Sub-Rulers of each sign, and help further deepen our understanding of each sign and decan. When we can layer in the meaning of each decan's ruling planet, we can get a fuller picture of the energy of each sign and the progression of energy within it. For each sign you have the Ruling Planet, and then three Sub-Rulers or Secondary Rulers related to the decans. For the rulers of the Decans there are two main schools of thought - the Chaldean Order or Modern Decans. I think both of these have value for different reasons. Mostly I use the Chaldean Order, but I also find value in the Modern Decan rulers as well. (There is also another system of decan rulership - the Ptolemy Table, which I am less familiar with so I am not showing it here today)
The Chaldean Order This is the system created by ancient Babylonians and seen as the "original" Western Astrological System of Decan Rulership. It follows an order of planets that repeats through the signs, related to the movement of planets from slowest to fastest. The Chaldean Order is Saturn, Jupiter, Mars, Sun, Venus, Mercury, Moon and this order repeats with every seven decans. The Tarot Card system of relating minor arcana cards to planets and signs is based on the Chaldean Order.
SIGN RULING PLANET 1st Decan 2nd Decan 3rd Decan Aries Mars Mars Sun Venus Taurus Venus Mercury Moon Saturn Gemini Mercury Jupiter Mars Sun Cancer Moon Venus Mercury Moon Leo Sun Saturn Jupiter Mars Virgo Mercury Sun Venus Mercury Libra Venus Moon Saturn Jupiter Scorpio Mars Mars Sun Venus Sagittarius Jupiter Mercury Moon Saturn Capricorn Saturn Jupiter Mars Sun Aquarius Saturn Venus Mercury Moon Pisces Jupiter Saturn Jupiter Mars
Image: The Chaldean Decans with associated Minor Arcana Tarot cards -
Modern Decans This is a reformulated modern system which assigns Planetary rulership based on the elements, and includes Modern planets such as Uranus, Neptune, and Pluto. This system has the first decan of each sign sharing the same planet as the Sign's major rulership, and the other two decans assigned planets by relation to the element of Fire, Air, Earth or Water. There is no repeating pattern or order of the planets by Decan.
SIGN MODERN RULER 1st Decan 2nd Decan 3rd Decan Aries Mars Mars Sun Jupiter Taurus Venus Venus Mercury Saturn Gemini Mercury Mercury Venus Uranus Cancer Moon Moon Pluto Neptune Leo Sun Sun Jupiter Mars Virgo Mercury Mercury Saturn Venus Libra Venus Venus Uranus Mercury Scorpio Pluto Pluto Neptune Moon Sag. Jupiter Jupiter Mars Sun Capri. Saturn Saturn Venus Mercury Aqua. Uranus Uranus Mercury Venus Pisces Neptune Neptune Moon Pluto
Astrology Students: Look at the planets in your birth chart by degree and apply the understanding of the Decan as well as the influence of the planetary ruler of the decan. How does this inform your understanding of that planet in the sign?
Do you prefer the Chaldean Decan ruler system, or the Modern Decan Ruler system? Can you incorporate wisdom of both or do you wish to use only one or the other? There are no "wrong" answers here, develop your own relationship with astrology!
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