1997 Mantra Corporation. All Rights Reserved. Jyotish is the most time-tested system of astrology in the world. In western countries, Jyotish is often referred to as Vedic, Indian, or Hindu astrology. This is the most important difference between Vedic and tropical astrology.
Tropical astrologers base their zodiac on the equinoxes instead.
The result is that the positions of the planets they calculate continues to change with respect to the stars. The arithmetical difference between planetary positions calculated sidereally and tropically is a value for what is called the precession of the equinoxes, or the Ayanaunsh. Today, this difference is 23 degrees 49 minutes and 17 seconds according to the official government calculation. Planetary positions in the sidereal and tropical systems coincide approximately every 26,000 years, the last such occasion being about the beginning of the Christian era. In Jyotish, the positions of the planets and other significant points are calculated with respect to a person's, or event's, birth data.