This page has been robot translated, sorry for typos if any. Original content here.

Ayanamsha (Ayanamsa, Ayanamsa, Ayanamsha)

Айанамша (Аянамса, Айанамса, Аянамша)

One of the most important differences between Vedic astrology and Western European is the use of the "fixed" (sidereal) Zodiac, while Western astrology uses the "moving" (tropical) Zodiac.

Due to the movement of the Earth’s axis in space (rotation of the Earth’s axis along a cone) - that is, due to the precession of the Earth’s axis - the Zodiac, which is calculated from the relative position between the Sun and the Earth, moves at a speed of approximately 1 minute per year (about 50.3 "per year). Currently, the moving (tropical) Zodiac is shifted relative to the fixed (real, that is, star-based) Zodiac by about 24 ° 00'04" (January 1, 2010), which is almost the entire sign of the Zodiac.

Jyotish [Vedic astrology] is sidereal, that is, “star” astrology. This means that Jyotish [Vedic astrology] uses the authentic - sidereal (fixed) - Zodiac to find the rashi [signs] in which the grahas [of the planet] and bhava [at home] are located .

Signs of the planets are very important in astrology. Since these two systems (Vedic and Western European) differ by almost a whole sign, even the most popular sign (the sign of the Sun), on the basis of which horoscopes are written in newspapers and magazines, is shifted back by one sign if the map will be recalculated for Vedic astrology. (Rashi [sign] is equal to 30 degrees in longitude. 12 signs, multiplied by 30 degrees, make up a 360-degree circle around the Earth - the Ecliptic).

In the sidereal (star) system , the Hirayan-system, the reference circle is the "stationary" Ecliptic . In the tropical system, it is believed that the vernal equinox occurs when the Sun is at the first point of the sign of Aries (0 degrees of Aries). This point is the source, or the base point of the Zodiac for finding the positions of celestial bodies. That is, to measure the celestial (astronomical) longitudes in the tropical system, the vernal equinox point (which is one of the two points of intersection of the Ecliptic and the Equator) was taken as the starting point . The vernal equinox is not fixed relative to the position of the stars, it always moves backward (westward) across the sky relative to the stars as a result of the precession of the equinoxes at a speed of 50.3 seconds per year, making a full Ecliptic revolution in about 26'000 years. Longitude, measured by this system, is called "tropical longitude" - "Sayan-longitude".

However, in the sidereal (star) system in order to fix the Zodiac (that is, to make it fixed), a certain point on the Ecliptic was taken as the beginning, and this made the system unchanged; this point of reference on the Ecliptic is fixed relative to fixed stars whose positions in the sky are fixed. The "longitude" of stars is constant and the rushi (the signs of the "Vedic Zodiac") always contain the same stars or groups of stars within their borders.

In this system, the longitude of celestial objects is measured relative to a fixed point on the Ecliptic, located among the stars. The distance between this fixed starting point and the moving point of the vernal equinox is called Ayanamsha (Ayanamsa) . In other words, Ayanamsha is the difference between the points of reference of the two systems. The longitude measured from the starting point of the sidereal system is called the sidereal (stellar) longitude - “Hirayana-longitude”.

The movement of the points of intersection of the Ecliptic (the visible path of the Sun) with the Heavenly Equator is called the recession of the equinoxes . In other words, precession is the movement of equinoxes along the ecliptic . There are many hypotheses about the point in time when the moving Zodiac coincided with the fixed Zodiac. Many experienced astronomers and astrologers paid considerable attention to this issue and obtained various results. And now almost every astrologer or astronomer has his own opinion about the date when the two Zodiac coincided.

In the matter of measuring the precession of the equinoxes, there are two quantities that need to be established: first, the speed of the precession and, second, the date of the zero precession (the date of coincidence of the fixed and moving Zodiacs). There are many different opinions about this.

According to Vedic Siddhanta, the precession rate of the equinoxes is determined by different authors of the following:

Author Annual precession rate
Aryabhatta 46.3 "
Parashara 46.5 "
Varaha Mihira 50.0 "
Surya-siddhanta 54.0 "
Vriddha Vasishta 54.0 "
Lahiri 50.3 "

The precession date set by various authors:

Author Zero Precession Date
Cyril Fagan 213 AD
P.Ch.Ray 319 AD
B.V. Raman 397 year BC
Sepharial 498 year BC
Vikram Sakha 56 year AD
Lahiri 285 AD

It is believed that Ayanamsha Lahiri is closest to the truth, although sometimes it is not entirely accurate, possibly due to the fact that the precession rate may be variable. The meaning of the real Ayanamshi lies between the Ayanamshah Lahiri and Raman. Beginners are recommended to use Ayanamsha Lahiri.