Ayanamsa

AYANAMSA

Whereas the earth and the other planets are very close to the Sun, they are too far away from the constellations (groups of stars). The distances of stars are measured in terms of light years. Our earth is only five minutes away from the Sun.

The earth's axis of rotation is inclined at an angle of 23 1/2° to the ecliptic. Owing to the gravitational pull exerted on the equatorial bulge by the luminaries and this inclination, the earth revolves like a spinning top, its pole describing a great circle (the Precessional Arc) in space every 26000 years (a Great Year). The notation is irregular and hence the variations in the lengths of Great Years from 23000 to 26000 solar years.

THE TWO ZODIACS

The wobble causes shifting of the equinoxes backward in space. During a Great Year, earth's pole aligns with different pole stars. At present Polaris is the North-pole star. Because of the precession of the equinoxes, the Tropical zodiac also moves with respect to the constellations (stars), which remain fixed in space several light years away. So, the sign Aries of the Tropical zodiac, which commences at the vernal equinox, no more coincides with the asterism called Ashwini, where the Sidereal zodiac starts. Moreover, the precessional movement is not uniform as we have said earlier. Debate has been going on since the last century about the exact precession of the equinoxes. (At present the Tropical Aries coincides with 5° Sidereal Pisces.)

While Western astrologers employ the Tropical Zodiac (moving) Zodiac, which commences at the vernal equinox, in Hindu astrology the starting point of the zodiac coincides with the asterism called Aswini and hence the name Sidereal (fixed ) Zodiac. Though the signs have the same names in both the zodiacs, the concepts are quite different. The time when the two zodiacs coincided is not exactly known. The rate at which the equinoxes move is also a point of dispute.

Hence the need for taking into account, the Ayanamsa, which is the difference in longitude between the two zodiacs. …………………………………………………………

………………………