What is the difference between Vedic Astrology and Western Astrology?

What is the difference between Vedic Astrology and Western Astrology?

In the Western system shift of the equinox is not taken into account

“In Western astrology, the astrological signs are determined by the position of the Sun in the sky, not the absolute positions of the constellations. Refuting a doctrine that astrologers don’t hold seems, at best, ancillary and probably irrelevant to any attack on astrology,” ~

From the longitude poison of the planets in the Zodiac at this moment, when this Ayanamsa is deducted, we get the correct longitude of the planets as applicable to our position on earth. In the western system as this shift of the equinox is not taken into account, all the planets are about 24 degrees ahead. The picture given bellow will give you an idea.

The Ecliptic System which positions planets by celestial latitude (from latin Latitudo width) and longitude (from Latin Longitudo length). The Equatorial System which positions stars by declination and right ascension. The term declination comes from the Latin – to bend away or to deviate and was used to measure the distance between the oblique circle (the ecliptic) and the celestial equator. Right Ascension (ascencio recta) was originally a measure of the time it takes for objects and signs on the ecliptic to rise – at a time when determining heliacal rising was important.

The Ecliptic System which positions planets by celestial latitude (from latin Latitudo width) and longitude (from Latin Longitudo length). The Equatorial System which positions stars by declination and right ascension. The term declination comes from the Latin – to bend away or to deviate and was used to measure the distance between the oblique circle (the ecliptic) and the celestial equator. Right Ascension (ascencio recta) was originally a measure of the time it takes for objects and signs on the ecliptic to rise – at a time when determining heliacal rising was important.

An effect called precession causes the Sun’s vernal equinox point to slowly shift westward over time, so a star’s RA and dec will slowly change by about 1.4 degrees every century (a fact ignored by astrologers), or about 1 minute increase in a star’s RA every twenty years. This is caused by the gravitational pulls of the Sun and Moon on the Earth’s equatorial bulge (from the Earth’s rapid rotation) in an effort to reduce the tilt of the Earth’s axis with respect to the ecliptic and the plane of the Moon’s orbit around the Earth (that is itself slightly tipped with respect to the ecliptic). Like the slow wobble of a rapidly-spinning top, the Earth responds to the gravitational tugs of the Sun and Moon by slowly wobbling its rotation axis with a period of 26,000 years.

This motion was first recorded by Hipparchus in 100 B.C.E. who noticed differences between ancient Babylonian observations and his own. When the Babylonians were the world power in 2000 B.C.E., the vernal equinox was in the constellation Aries and the star Thuban (in Draco) was the closest bright star to the NCP. At the time of Jesus Christ the vernal equinox had shifted to the constellation Pisces and the star Kochab (in the bowl of the Little Dipper) was the closest bright star to the NCP. Now the star Polaris is close to the NCP and the vernal equinox is close to the border between Pisces and Aquarius (in 2600 C.E. it will officially be in Aquarius) which is what a popular song of years ago refers to with the line “this is the dawning of the Age of Aquarius”. In the year 10,000 C.E., the bright star in the tail of Cygnus, Deneb, will be the pole star and Vega (in Lyra) will get its turn by the year 14,000 C.E. Horoscopes today are still based on the 4,000-year old Babylonian system so even though the Sun is in Aries on my birthday, the zodiac sign used for my horoscope is Taurus. I guess it’s hard to keep up with all of the changes in the modern world!

                                                           Star Chart sites

Thus, the tropical year, measuring the cycle of seasons (for example, the time from solstice to solstice, or equinox to equinox), is about 20 minutes shorter than the sidereal year, which is measured by the Sun’s apparent position relative to the stars. Note that 20 minutes per year is approximately equivalent to one year per 25,772 years, so after one full cycle of 25,772 years the positions of the seasons relative to the orbit are “back where they started”. (In actuality, other effects also slowly change the shape and orientation of the Earth’s orbit, and these, in combination with precession, create various cycles of differing periods; see also Milankovitch cycles. The magnitude of the Earth’s tilt, as opposed to merely its orientation, also changes slowly over time, but this effect is not attributed directly to precession.)

Hipparchus also studied precession in On the Length of the Year. Two kinds of year are relevant to understanding his work. The tropical year is the length of time that the Sun, as viewed from the Earth, takes to return to the same position along the ecliptic (its path among the stars on the celestial sphere).

The sidereal year is the length of time that the Sun takes to return to the same position with respect to the stars of the celestial sphere. Precession causes the stars to change their longitude slightly each year, so the sidereal year is longer than the tropical year. Using observations of the equinoxes and solstices, Hipparchus found that the length of the tropical year was 365+1/4-1/300 days, or 365.24667 days (Evans 1998, p. 209). Comparing this with the length of the sidereal year, he calculated that the rate of precession was not less than 1° in a century. From this information, it is possible to calculate that his value for the sidereal year was 365+1/4+1/144 days (Toomer 1978, p. 218). By giving a minimum rate he may have been allowing for errors in observation.

Another point that deserves attention: Today’s “Vedic” astrology and calendar calculation are purely sidereal, i.e. they ignore the seasons, equinoxes, and solstices.

இந்திய சோதிடம் பருவகாலங்களை, சம பகல்இரவு நிகழ்வுகள் மற்றும் கடகக் கோடு மகரக் கோடு புள்ளிகளை  கணக்கில் எடுக்கவில்லை. இதனால் சமய விடுமுறைகள், கிரிகைகள், யாகப்பலிகள் பிழையான நாட்களில்  கொண்டாடப்படுகின்றன.

This discrepancy is caused by the fact that Western Astrology uses the spring equinox as a point of reference in the calculation of the chart. According to this system, the Sun enters Aries on the spring equinox. While this was true 2,000 years ago when Western Astrology was born, it is no longer astronomically accurate. Due to a small wobble in the rotation of the earth, at spring equinox the Sun can be observed in the constellation of Pisces (7 degrees of Pisces).

To quantify this discrepancy astrologically, if you were born between the 15th and the 20/21st of any month, you will find that your Western Sun sign is moved back by one sign in the Vedic chart. So instead of Taurus for example (in western) you are Aries (in vedic).

 The beginning of the lunar mansion Dhaniṣṭhā.

Today’s Vedic tradition ignores all these statements, with grotesque consequences. They do not celebrate the “northward path” (uttarāyanam) of the Sun on its correct date around 21 December, but in mid-January on the day of the Sun’s ingress into sidereal Capricorn (makarasaṃkrāntiḥ). Nowadays, the month of Māgha falls into January and February and has nothing to do with the solstice anymore. As a result, from the point of view ancient Vedic religion, all religious holidays, rituals, and sacrifices that are bound to a calendar date are celebrated on “wrong” days. This is actually a catastrophe, because the rituals must be performed on their correct dates in order to become efficient. Some Indian scholars, such as Avtar Krishen Kaul and Darshaney Lokesh, are well aware of this problem and fight for a tropical reform of the Vedic calendar.

Also interesting to note: According to current Indian astrology the zodiac begins with Aries and the lunar mansion Aśvinī. But in Vedic texts, lists of the lunar mansions always start with Kṛttikā, which corresponds to the Pleiades in sidereal Taurus. Besides, Kṛttikā is the most often mentioned lunar mansion in the Vedas, whereas Aśvinī hardly ever appears. The reason for this prominence of Kṛttikā in the Vedas lies in the fact that, in ancient times, approximately from 2500 BC on, the vernal equinox was located in this lunar motion. In astronomical and astrological texts of Late Antiquity, the lunar mansion Aśvinī (and Aries) became the starting point of the ecliptic, and the reason was, again, that the vernal equinox by that time had moved on into this lunar mansion. The equinoxes and solstices were placed at the beginnings of Aries, Cancer, Libra, and Capricorn. Incidentally, the vernal point has since crossed the whole lunar mansion of Revatī and is currently in Uttarabhādrā. Nowadays’ “Vedic” astrology therefore works with a zodiac that was defined by the equinoctial points of more than 1500 years ago and never updated.

From all this it becomes clear that even though we do not know much about the “astrology” of the Vedic period, it must have been radically different from so-called “Vedic” astrology as we know it today.

The oldest astrological textbook in Sanskrit that knows the zodiac is the Yavanajātaka (“Nativity according to the Greeks”) by Sphujidhvaja, who lived in the first centuries CE. According to its own statement, this textbook goes back to a Greek source. In reality, however, the text is rather an amalgamate of Indian and Greek elements. The authors Varāhamihira (6th century AD) and Kalyāṇavarman (800 AD) also refer to Greek astrologers with great respect and even reverence.

The Lahiri Ayanāṃśa is defined as having the initial point of sidereal Aries and the lunar mansion Aśvinī exactly opposite the star Citrā (= Spica, α Virginis), with Citrā itself exactly in the middle of the lunar mansion to which it has lent its name. This Ayanāṃśa had the value 0 in the year 285 AD; in this year the sidereal Lahiri zodiac and the tropical zodiac coincided with each other.
spica : கன்னி வான்மனையின் ஒளிமிக்க விண்மீன் வகை .

An azimuth ( i/ˈæzɪməθ/) (from Arabic al-sumūt, meaning “the directions”) is an angular measurement in a spherical coordinate system.

What is the difference between Vedic Astrology and Western Astrology?

Vedic Astrology is also known as Sidereal Astrology because it tracks the position of the Sun, Moon and planets against the position of the stars. Western Astrology is also known as Tropical Astrology because it tracks the Sun, Moon and planets in relation to the Earth and its seasonal points.

The difference between these two starts of the astrological year is called the ayanamsa. You will find that unless you were born between the 15th and 20th of the month, your sign will have moved back by one in Vedic Astrology.

In fact, every 72 years the Vernal Equinox shifts back (or precedes) by 1º. The Age of Aquarius will start when the Sun rises in Aquarius on the morning of the Vernal Equinox in about 430 years. Vedic Astrology will recognise this but Western Astrology will start the year at 1º Aries. That is not to say that there are not different systems within Vedic traditions. The official calculations of ayanamsa are based on the calculations of N. C. Lahiri but there are also systems in use based on Raman, Krishnamurti and Sri Yukteswar.

In astronomy too, this is the difference between the length of a tropical year (365.2422 rotations of the earth) and a sidereal year (365.2563 rotations) required to complete one orbit relative to the sun (tropical) or stars (sidereal).

The sidereal ecliptic longitude of a celestial body is its longitude on the ecliptic defined with respect to the “fixed” stars.

The tropical ecliptic longitude of a celestial body is its longitude on the ecliptic defined with respect to the vernal equinox point.
“Ayanamsha” means “precession rate ” or”precessional distance” regarding the precession of the equinoxes.
Ayana = “progress or”forward movement”;
Amsha= “portion” or”section”.
The precession of the equinoxes means that the four equinoctial points (spring, summer, autumn, and winter equinoxes) are constantly moving. They will rotate (backwards) through all 360 degrees and return to their starting point every 25920 [solar] years.

The Sidereal Zodiac used in Vedic Astrology is astronomically accurate because it takes the shifting of the earth’s axis into account when calculating the longitudes of the planets and constellations.

The Tropical Zodiac used in Western Astrology is a Symbolic Zodiac based upon the position of 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 needs to subtract the current ayanamsa from the Tropical longitudes of the planets and signs to get their Sidereal positions. Because the earth’s axis is always changing its position the ayanamsa changes slightly every year.

In January 1, 1900 the ayanamsa was 22 degrees 27 minutes 59 seconds.

Today the ayanamsa is 23º 52′ degrees

On 14 April the sun still transits that spot which used to be Vernal equinox around 500 AD. In this way spring will traverse through all the constellations. In the year 13460 AD , vernal equinox will fall on 23 September and the pole star will be Vega.

The problem with the old visible star based measurement is that the stellar positions are slowly moving backwards relative to the Earth’s seasons and year at the rate of approximately 1º every 72 years. This slippage is known as the Precession of the Equinox and it is why some believe that we are in the Age of Pisces and moving into the Age of Aquarius.

“In Western astrology, the astrological signs are determined by the position of the Sun in the sky, not the absolute positions of the constellations. Refuting a doctrine that astrologers don’t hold seems, at best, ancillary and probably irrelevant to any attack on astrology,”

Again, observation and record keeping allowed Astrologers to realize that an eclipse of the moon only happened during a Full Moon, and a solar eclipse only happened during a New Moon.

இந்திய சோதிடம் பருவகாலங்களை, சம பகல்இரவு நிகழ்வுகள் மற்றும் கடகக் கோடு மகரக் கோடு புள்ளிகளை  கணக்கில் எடுக்கவில்லை. இதனால் சமய விடுமுறைகள், கிரிகைகள், திருவிழாக்கள், யாகப்பலிகள் பிழையான நாட்களில்  கொண்டாடப்படுகின்றன. ஏப்ரில் 14 அன்று ஞாயிறு கிபி 285  ஆம் ஆண்டில்  வேனில் சமயிரவாக இருந்த அதே புள்ளியை கடந்து செல்கிறது. இதுபோல்  ஞாயிறு எல்லா நட்சத்திரக் கூட்டங்களையும் கடந்து போகும்போது வேனில் சமயிரவு கிபி 13,460 ஆண்டில்   செப்தெம்பர் 23 இல் இடம்பெறும். அப்போது  புவியின்  வான்அச்சு இப்போதுள்ள துருவநட்சத்திரத்துக்குப் ( பதில் வேகா (Vega) என்ற நட்சத்திரத்தை நோக்கியிருக்கும்.  அப்போதும் ஜெயலலிதா உயிரோடு இருந்தால் வேனில் காலம் ஏப்ரில் 14 இல் தொடங்கும் என்று அடம்பிடிப்பாரா?