Tamil Astrology

Ecliptic Path: Source: Wikpedia (Wikimedia Commons)

Zodiac Signs Shown around the Earth and Other Planets in their Orbits

Dragon Head or Rahu and Dragon Tail or Ketu: Shadowy planets. Source: Astrology Planet Raghu - Ketu

Precession of the Equinoxes Source:
The Tropical and Sidereal Zodiaks & The Cycle of Earth's Precessional Cross

inner wheel - tropical zodiac  outer wheel - sidereal zodiac Source: You are Who You are?

Our Sages or Rishis of the Vedic period (Narada, Vasistha, Saunaka, Jaimini and others) were able to perceive the mysterious star and planetary movements along the zodiacal system through their deep meditation (thapas). They conceived the basic rules of the "nirayana" or sidereal zodiacal system (Fixed star astrology) which formed the basis for Indian Vedic Astronomy as well as Vedic Astrology. It is different from Western Tropical astrology or the Moving star system. If a birth chart cast using these tropical and sidereal system, there  will be the variation of 23 to 24 degrees. Accordingly (for example) if the Tropical system horoscope shows the sun in Aquaris, then the sidereal system will indicate the Sun in Capricorn.

Many more Indian astrological traditions shared common roots in ancient philosophies that influenced each other and Tamil astrology, a natural cosmic tradition, branched out from the Indian Vedic Astronomy.  Tamil astrology,  is estimated as one of the most ancient, accurate and consistent form of astrology from India. Its basic principles and unique methodologies are derived from the principles of Sidereal (Eastern) astrology. The sidereal system claims that the position of planets in their orbits observable and the astronomical calculations are scientific and  measurable.

The Tamil astrology study consists of 27 constellations, in 12 lunar mansions. The movements of two luminaries Sun and Moon, five major planets (Mars, Jupiter, Saturn, Venus and Mercury) and the two nodal points of the Moon i.e., Rahu and Ketu are considered and their positions are marked.

Nine Planets

According to Tamil Astrology there are only nine Planets or Grahas which have innumerable influence on human life. Of the nine planets only seven planets are known heavenly bodies: Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn. The remaining two, namely Dragon Head or Rahu and Dragon Tail or Ketu, are known as shadowy planets. Why it is called as shadowy planets? The two planetary positions are calculated mathematically.

Twelve Zodiac Signs

The Tamil Astrology system also conceived the zodiacal system (Circle of animals). It is an elliptical belt along the solar path. This zodiacal belt is extended for about eight degrees on either side of this solar path. Along this zodiacal belt the sun, moon and other planetary motions takes place. Tamil Astrology divides this zodiacal belt comprising 360 degrees into 12 equal parts. Each part of 30 degrees was called as sign or Rasi. This is considered as the fundamental division of Tamil Astrology. The Western terminology of the 12 zodiac signs or rasis and their Sanskrit names are : 

1.Aries: Mesha "Ram, goat." ; 

2.Taurus: Vrishabha "Strength," or "a bull." ; 

3.Gemini: Mithuna "Twins"; 

4.Cancer: Kataka "Crab." ; 

5.Leo: Simha "Lion;" ; 

6.Virgo: Kanya "Maiden;" ; 

7.Libra: Thula "Balance"; 

8.Scorpio: Vrishchika "Scorpion." ; 

9.Sagittarius: Dhanus "Bow;" ; 

10.Capricorn: Makara "Crocodile"; 

11.Aquarius: Kumbha "Water vessel;" ; 

12.Pisces: Meena "Fish;"

27 Star-clusters or Constellations

The Tamil Astrology also set relation between 12 zodiacal signs or rasis and 27 star-clusters and constellations. These unique 27 star-clusters or constellations spread within the elliptic zodiac orbit (solar orbit). Tamil Astrology divides 27 equal divisions of the zodiac orbit (comprising 360 degrees) and each star-cluster and constellation will occupy 1/27 parts or 13 degree 20' of the zodiac orbit. As a result astrology system brings 27 star-clusters or constellations under 12 zodiac signs and unifies both the divisions together.

The twenty-seven nakshatras are: Asvin, Bharani, Krittika, Rohini, Mrigasira, Ardra, Punarvasu, Pushya, Aslesha, Magha, Purvaphalguni, Uttaraphalguni, Hasta, Chaitra, Svati, Visakha, Anuradha, Jyeshtha, Mula, Purvashadha, Uttarashadha, Sravana, Dhanishtha, Satabhishaj, Purvaprostapada, Uttaraprostapada and Revati.

Planetray Transitions in Zodiac Signs / Stellar Constellations

According to Tamil Astrology the nine planets are related to the 12 zodiac signs or rasis and 27 stellar-clusters or constellations. Planetary transitions and its influence on individuals will be calculated according to the birth star (ruling constellation at the time of his birth). Each individual will be related with the respective stellar cluster and zodiac sign at the time of his / her birth. When there are planetary transitions occurring across each specific stellar constellation / zodiac sign, there will be significant influence planets on all the natives.

 Reference Sources:

1.     Sidereal astrology http://en.wikipedia.org/wiki/Sidereal_astrology
2.     Constellation http://en.wikipedia.org/wiki/Constellation
3.     Zodiac http://en.wikipedia.org/wiki/Zodiac
4.     Nakshatra http://en.wikipedia.org/wiki/Nakshatra

YouTube 

Western Astrology vs Vedic Astrology (Mathematical and Scientific Explanation by KRSchannel