Astrology is method of predictions based on astronomy. Vedic or Hindu astrology and Western astrology both are based on the concept of astronomy or the study of stars which moves in the zodiacal belt. As the earth complete its revolution around the Sun once in 365 days 5 hours 48 minutes and 46 seconds. When considering it from the Earth [geocentric- where we take Earth in the centre and all heavenly bodies revolving around it] – means the Sun appears to complete one ecliptic round and this is tropical year.

During this completion of tropical year the earth regains its original angular position with the Sun. this is responsible for change of seasons. From one vernal equinox to the other it will take one complete tropical year. During this tropical year from one vernal equinox to the next, we consider the position of the earth with reference to a fixed star – Chitra – spica of the zodiac, the earth appears to lie some 50.26 seconds of celestial longitude to the west of its original position. Sidereal year is one complete revolution of the earth with respect to the fixed star Chitra or Spica. This is 20 minutes longer than tropical year. This point, the first point of Aries or the vernal equinox, goes on receding westward at a rate of approximately 50.26 seconds of arc each year. This is called the precession of the equinoxes. However, in Nirayan System the reference point is fixed. It is 180º away from the Chitra Nakshatra and that point is referred to as the first point of Aries.

The movement of this point is then subtracted in the calculations and we get without ayan means a niryana position of the planets. That is why when a person born with Sun in Virgo according to Western astrology will have Sun in Leo according to Vedic astrology. This distance at any given epoch is called as the Ayanamsha .The ayanamsha indicates the difference between the fixed zodiac and the movable zodiac. The system that considers the fixed zodiac is called the Niryana (without ayana!) system, while the one that considers the movable zodiac is called the Sayana (with ayana!) system. The Niryana values of planetary longitudes can be obtained by subtracting the ayanamsha for a given time from the Sayana longitudes. According to Vedic astrology it is exact and fixed and not changing. Therefore Vedic astrology bears better tools than Western Astrology.

Which System Is Superior

Vedic system or western Astrology

Both systems are appropriate at their own place. But Vedic system of astrology is based on the strong astronomical principles which are more accurate so this system is much better. According to my point of view, if you use Vedic system in calculations then apply the Vedic methods of predictions whereas if you apply Western calculations then apply Western method of prediction. But Vedic system indeed has better tools and methods to predict. It is supported by many Vargas i.e. divisional charts which help in knowing the event in its specific area, there are many dasha systems to cross check the event at the right time etc.