Decans in Astrology

Patricia Lantz C.Ht.
Astronomical Ceiling, Temple of Hathor Dendera, Egypt

The decans give a shade of additional meaning to each astrological sign. You could say that metaphorically the decans are like dropping a bit of blue paint into a bucket of red paint. The paint in the bucket is still red, but it's a slightly different shade of red. In natal astrology, the 36 decans are associated with traits that add a shade of difference to the characteristics of your astrological Sun sign. Some astrologers believe decan based astrology is more effective because it reveals 36 types of personalities instead of 12.

History of the Decans

The history of the decan begins in ancient Egypt around the 5th century BCE. The Egyptian decans are based on the asterisms (small star groups) that rose consecutively and regularly on the horizon due to the earth's rotation. Decans were initially used by the Egyptians as a sidereal star clock. The ancient Egyptians believed that the deities manifest in certain forms and at specific times. It's likely that the decans brought this belief into the Greek zodiac and may explain why they were absorbed the way they were, as sections of each zodiac sign.

Western Astrology

Western astrology has its roots primarily in Mesopotamia. It was the Mesopotamians who eventually developed the signs of the zodiac and the concept of natal astrology. While this was happening in Mesopotamia, the Egyptians astrologers were developing the decans. These two astrological traditions came together sometime around the 1st Century BCE and the 36 decans were merged with the astrological signs.

The Modern Astrological Decans

natal charts

Each of the astrological signs of the zodiac is an arc of 30° in the 360° astrological zodiac. Each sign is subdivided into three decans of 10° each. In modern astrology, the three decans of each sign are defined by the three signs of the same element (triplicity) and the traditional ruling planets of those signs.

The Fire Signs

  • Aries ruled by Mars
  • Leo ruled by the Sun
  • Sagittarius ruled by Jupiter

The Earth Signs

  • Taurus ruled by Venus
  • Virgo ruled by Mercury
  • Capricorn ruled by Saturn

The Air Signs

  • Gemini ruled by Mercury
  • Libra ruled by Venus
  • Aquarius ruled by Saturn/Uranus

The Water Signs

  • Cancer ruled by the Moon
  • Scorpio ruled by Mars/Pluto
  • Pisces ruled by Jupiter/Neptune

The Decans in Tarot

In Tarot decks there are 36 cards in the Minor Arcana numbered 1-10 that are divided into four suits. Each of these numbered cards represents one zodiacal decan. Just like the 12 astrology signs, each suit of the Minor Arcana is related to one of the four elements. Many Tarot readers combine tarot with astrology and use the decans to gain a deeper understanding of the numbered cards when doing a Tarot spread.

The Suits of the Minor Arcana

  • Fire is Wands
  • Earth is Disks or Pentacles
  • Air is Swords
  • Water is Cups

Table of Decans

To find out the decan of your Sun sign, you'll need to know the degree the Sun was on the day you were born. The easiest way to find this degree is to use the free tool at Astro-Seek to calculate your horoscope.

Sign First Decan
0 - 9.59°
Second Decan
10 - 19.59°
Third Decan
20 - 29.59°
Aries Aries/Aries
Mars
Two of Wands
Aries/Leo
Sun
Three of Wands

Aries/Sagittarius
Jupiter
Four of Wands

Taurus

Taurus/Taurus
Venus
Five of Disks

Taurus/Virgo
Mercury
Six of Disks

Taurus/Capricorn
Saturn
Seven of Disks

Gemini

Gemini/Gemini
Mercury
Eight of Swords

Gemini/Libra
Venus
Nine of Swords

Gemini/Aquarius
Saturn/Uranus
Ten of Swords

Cancer Cancer/Cancer
The Moon

Two of Cups

Cancer/Scorpio
Mars/Pluto
Three of Cups
Cancer/Pisces
Jupiter/Neptune
Four of Cups
Leo Leo/Leo
The Sun
Five of Wands
Leo/Sagittarius
Jupiter
Six of Wands
Leo/Aries
Mars
Seven of Wands
Virgo Virgo/Virgo
Mercury
Eight of Disks
Virgo/Capricorn
Saturn
Nine of Disks
Virgo/Taurus
Venus
Ten of Disks
Libra Libra/Libra
Venus
Two of Swords
Libra/Aquarius
Saturn/Uranus
Three of Swords
Libra/Gemini
Mercury
Four of Swords
Scorpio Scorpio/Scorpio
Mars/Pluto
Five of Cups
Scorpio/Pisces
Jupiter/Neptune
Six of Cups
Scorpio/Cancer
The Moon

Seven of Cups

Sagittarius Sagittarius/Sagittarius
Jupiter
Eight of Wands
Sagittarius/Aries
Mars
Nine of Wands
Sagittarius/Leo
The Sun
Ten of Wands
Capricorn Capricorn/Capricorn
Saturn
Two of Disks
Capricorn/Taurus
Venus
Three of Disks
Capricorn/Virgo
Mercury
Four of Disks
Aquarius Aquarius/Aquarius
Saturn/Uranus
Five of Swords
Aquarius/Gemini
Mercury
Six of Swords
Aquarius/Libra
Venus
Seven of Swords
Pisces Pisces/Pisces
Jupiter/Neptune
Eight of Cups
Pisces/Cancer
The Moon
Nine of Cups
Pisces/Scorpio
Mars/Pluto
Ten of Cups

Is it Necessary to Know the Decans?

Not all astrologers use decans, some use only a few, and some use decans all the time. The decans and their rulers have proven to be very useful in tarot readings and predictive astrology, especially in the progressed horoscope. Sometimes they complete the story, and at other times they help pinpoint the nature of activity going on in the subject's life. Is it necessary to know the decans? Probably not, but once you begin using them, they can add some surprisingly accurate twists to your Sun sign and other planetary placements.

Decans in Astrology