Decan

Origin

The decan system originates in ancient Egypt, where decans were originally a system of thirty-six stars or star groups, one for each ten-day period of the Egyptian civil calendar (twelve months of thirty days plus five intercalary days). These decanal stars rose just before the Sun on successive ten-day periods through the year, allowing a precise measurement of time at night. The decans were closely associated with Egyptian deities and were used in religious and magical practice as well as timekeeping. Egyptian zodiacs from the Hellenistic period, such as the famous Dendera zodiac, depict the decans as figures encircling the zodiac signs.

When Hellenistic astrology synthesised Egyptian and Babylonian traditions in the centuries around the turn of the common era, the decans were incorporated into the zodiacal system. The Greek astrologers assigned planetary rulers to each decan, originally using the Chaldean order of the seven traditional planets cycling through the thirty-six decans. Later, two main decan ruler systems developed: the Chaldean system based on the Chaldean planetary order, and the triplicity system based on the elemental triplicities, in which the three signs of each element rule the three decans of each sign in that element. Both systems remain in use today, with the triplicity system most common in modern Western astrology.

Meaning and function

In the triplicity system most commonly used in modern Western astrology, the three decans of each sign are ruled by the three signs of the same element in zodiacal order. For Aries (a fire sign), the three decans are ruled by Aries (zero to ten degrees), Leo (ten to twenty degrees), and Sagittarius (twenty to thirty degrees), the three fire signs. For Taurus (an earth sign), the three decans are ruled by Taurus, Virgo, and Capricorn, the three earth signs. For Gemini (an air sign), the three decans are ruled by Gemini, Libra, and Aquarius, the three air signs. For Cancer (a water sign), the three decans are ruled by Cancer, Scorpio, and Pisces, the three water signs. The pattern continues through the zodiac.

A planet in the first decan of a sign expresses the pure quality of that sign; a planet in the second decan adds the flavour of the next sign of the same element; a planet in the third decan adds the flavour of the third sign of the element. So a Sun at five degrees Leo (first decan) is purely Leonine; a Sun at fifteen degrees Leo (second decan, Sagittarius-flavoured) is Leo with a philosophical adventurous edge; a Sun at twenty-five degrees Leo (third decan, Aries-flavoured) is Leo with a pioneering warrior edge. The decan refinement applies to all chart factors: planets, angles, and house cusps gain their decan flavour from their precise degree.

In practice

In your natal chart, find each planet's exact degree and identify which decan it falls in. The first decan is zero to nine degrees fifty-nine minutes; the second decan is ten degrees to nineteen degrees fifty-nine minutes; the third decan is twenty to twenty-nine degrees fifty-nine minutes. The pure signs of the first decan, the cross-influenced second and third decans, and the cusp degrees between decans (about ten and twenty degrees of each sign) are the points where the decan flavour is most concentrated. Planets close to a decan boundary participate in the qualities of both decans.

Common configurations include the Sun in a particular decan as a refinement of solar identity (a person born under late Cancer with the Pisces-decan flavour will have a more mystical or dreamy emotional life than one born in the early Cancer decan); the Moon in a particular decan as a nuance of emotional life; the Ascendant's decan as a colour added to the rising sign. The decan system also relates closely to the Tarot Minor Arcana: the thirty-six decans of the zodiac correspond to the thirty-six numbered cards from two through ten in each of the four suits, with each card representing one decan. To work with your decans, attend to the second-layer flavour each planet carries from its decan ruler, and observe how this nuance shows up in the actual texture of your life.

Symbolic depth

The decans are the smallest classical subdivision of the zodiac to carry rich symbolic meaning, the level at which the zodiac is read with full nuance. The thirty-six decans are sometimes pictured as the thirty-six demons of ancient magic, the thirty-six guardian spirits of the days, or the thirty-six sacred figures encircling the wheel of the year. In Egyptian magical practice the decans were invoked for protection, healing, and timing of ritual. The Greek magical papyri preserve detailed decanal magic, and the Hermetic literature of late antiquity transmitted the decanal system to medieval Arabic and European astrology and magic.

In the tarot, the thirty-six decans correspond exactly to the thirty-six pip cards numbered two through ten in each of the four suits. The Golden Dawn system, elaborated by S. L. Mathers and used in the Rider-Waite-Smith and Thoth tarots, assigns each pip card to a specific decan, giving cards such as the Two of Wands (first decan of Aries), Three of Wands (second decan of Aries), and so on through the year. This correspondence is one of the deepest links between astrology and tarot. In Vedic astrology the equivalent system is the Drekkana, the third division of a sign, and is used in the deeper layers of chart interpretation. Continue through the glossary.

Also known as

• Decanate
• Face
• Drekkana
• Ten-degree subdivision
• Decan ruler