THE DIFFERENCE BETWEEN THE VEDIC (SIDEREAL) ZODIAC AND
THEWESTERN (TROPICAL) ZODIAC
by Prash Trivedi
It is important to know what differentiates Vedic Astrology from
the more well knowWestern Astrology.
Vedic Astrology or Jyotish (its Sanskrit name meaning Jyoti -
Light and Isha - Lordis based upon the Sidereal Zodiac as opposed
to the Tropical Zodiac used inWestern Astrology.
Although the Sidereal Zodiac was used by Western Astrologers
like Ptolemy in thbeginning, over the course of time a more
symbolic zodiac was adopted which isastronomically inaccurate.
This difference between the two zodiacs is called the
"Ayanamsha". TheAyanamsha takes into account the revolution of the
earth's axis, a phenomenon iAstrology known as the "precession of
the equinoxes".
To explain this in the simplest way possible the earth
spins(wobbles to be moreprecise) on its own axis in a conical
motion and takes approximately 25,800 yearscomplete one revolution.
It means that every 2000 years the position of the vernaspring
equinox, which marks the beginning point of the first sign of the
zodiac Arieis always changing and moving forwards in time.
Consequently the pole star also changes every few thousand years
as seen in thefigure below.
7/28/2019 Ayanamsa &Zodiac
2/2
When a person born today has the Sun at 10 degrees in Aries
using the TropicalZodiac, in actual astronomical reality the Sun
will be 23 degrees backwards placein the sign of Pisces.
For example when the Sun used to move into Aries on the 21st of
March at 200
A.D. today it will enter the sign of Aries around the 14th of
April. When the Sunmoved into the sign of Scorpio on the 22nd
October at 200 A.D. today it will enterthe sign of Scorpio around
the 14th of November.
This the reason why the present daySUN-SIGN ASTROLOGY is
COMPLETELY WRONG.It is a complete joke in more ways than one - it
has very little to do with Real Astrology. It istime that it was
erased from public/media consciousness.The Sidereal Zodiac used in
Vedic Astrology is astronomically accurate because it takes
theshifting of the earth's axis into account when calculating the
longitudes of the planets andconstellations.The Tropical Zodiac
used in Western Astrology is a Symbolic Zodiac based upon the
positioof the planets and constellations as they were in the sky
2000 years ago. The Sidereal zodiac is the real zodiac as it
actually appears in the sky at any given moment
In order to convert a Western (tropical) horoscope into a Vedic
(sidereal) horoscope one neto subtract the current ayanamsa from
the Tropical longitudes of the planets and signs to getheir
Sidereal positions. Because the earth's axis is always changing its
position the ayanamchanges slightly every year.In January 1, 1900
the ayanamsa was 22 degrees 27 minutes 59 seconds. Today the
ayanamsa is 23 52' degrees.There are various ayanamsas in use
today. There are some disagreements on the actualmeasurement of the
ayanamsa or longitudinal difference between the two zodiacs. The
mospopular and widely accepted ayanamsa in India was introduced by
N.C. Lahiri. He calculatethe precessional rate to be around 48
seconds per year.
