The Decans are 36 groups of stars (small constellations) which rise consecutively on the horizon throughout each earth rotation. Since a new decan appears every ten days, the ancient Greeks called them dekanoi (pl. of dekanos) or "tenths". In Vedic astrology, each sign of the zodiac (30 deg.) is divided by three decans, 10 degrees each. There is the trinal calculation which utilizes the elemental trines to each sign. Each decan has its planetary ruling planet or planets.
To find Decanate cards, we use the same method as with the planetary ruling cards. All we need to know is planets that rule the Decan of our Sun placement (in the astrological birth chart). It can be one or two ruling planets, and therefore one or two decanate cards (see table below).
Please, note that dates below ruling planets of each decan are approximate. To be precise, you need to find the actual degree of your Sun placement in your astrological birth chart.
Now you can calculate your astrological birth chart for FREE and find out your exact Decanate Cards immediately - start with your birth chart
| Sign | First Decan 01 - 10 | Second Decan 10 - 20 | Third Decan 20 - 30 |
| Aries | Mars, Pluto R March 21-30 |
Sun March 31 - April 9 |
Jupiter, Neptune R April 10-19 |
| Taurus | Venus R April 20-30 |
Mercury May 1-10 |
Saturn May 11-20 |
| Gemini | Mercury R May 21-31 |
Venus June 1-10 |
Saturn, Uranus June 11-21 |
| Cancer | Moon June 22 - July 1 |
Pluto, Mars R July 2-11 |
Neptune, Jupiter R July 12-22 |
| Leo | Sun July 23 - August 1 |
Jupiter, Neptune R August 2-12 |
Mars, Pluto R August 13-22 |
| Virgo | Mercury August 23 - September 2 |
Saturn September 3-12 |
Venus September 13-22 |
| Libra | Venus September 23 - October 2 |
Uranus, Saturn R October 3-12 |
Mercury R October 13-23 |
| Scorpio | Pluto, Mars R October 24 - November 2 |
Neptune, Jupiter R November 3 - 12 |
Moon November 13-22 |
| Sagittarius | Jupiter, Neptune R November 23 - December 2 |
Mars, Pluto R December 3 - 12 |
Sun December 13-21 |
| Capricorn | Saturn December 22-31 |
Venus R January 1-10 |
Mercury January 11-20 |
| Aquarius | Uranus, Saturn R January 21-30 |
Mercury R January 31 - February 9 |
Venus February 10-18 |
| Pisces | Neptune, Jupiter R February 19-29 |
Moon March 1-10 |
Pluto, Mars R March 11-20 |
