One of the main differences between Indian astrology and western astrology is in the number of planets they use. Consider this:
Western Astrology uses: Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus,
Vedic Astrology uses: Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Rahu & Ketu. (Total of 9)
Now which one of the above is correct and scientific? Give it a little thought and you can arrive at the conclusion yourself! 9 planets would be my contention. We need not use any more than 9 planets.
How many numbers does the base ten system of numbering have? Nine numbers (1 to 9). Can something go beyond nine? Do this simple test: Take any number and multiply it by 9. Add each of the digits of the product until it is reduced to a single digit. The result will be 9 always.
Example 1: Take 392, multiply by 9, the answer is 3528. Add all the digits until it is reduced to a single number. 3+5+2+8 = 18 = 1+8 = 9.
Example 2: Take 7396, multiply by 9 = 66564 = 6+6+5+6+4 = 27 = 2+7=9.
Only the number 9 has this unique property. Try this with any other digit and it will not work. 9 signifies the limit. You can’t go beyond 9. You do not need anything more than 9.
If you are still not convinced, how many colors does white light have? Seven. Each color for one planet. Vedic astrology uses these 7 for the inner planets and it adds two more, Rahu (moons north node) and Ketu (Moons south node) bringing the total to 9.
The outer planets Uranus, Neptune and Pluto are too distant to influence mankind. That is why they were left out of Jyotish. Already Jyotish has had one victory with the down grading of Pluto which is no longer considered a planet.
Western astrology has also given ruler ship of some signs to these outer planets. For example Pluto rules Scorpio according to western astrology. The noted astrologer Linda Goodman of yesteryears had said that 2 more planets are due to be discovered and they will rule Virgo and Taurus! Eventually it will be 12 signs and 12 planets according to western astrology. In Vedic astrology 2 zodiac sign are ruled by 1 planet. Mars for example rules Aries and Scorpio. In western astrology Mars rules only Aries and Scorpio is ruled by the now down graded Pluto.
It is not known if the sages of the past knew about the existence of outer planets but it is said that Maharishi Vyasa knew about the existence of Pluto. But nowhere are outer planets given sanction in