In Vedic Astrology, among all the Dasa systems formulated by sage Parasar, the Vimsottari dasa system is most popular and widely used.
Though Varahamihir extensively used Moola Dasa system and used planetary positions in Shashtyama chart (D-60) to predict exact dates of events, based on past life karma, this system lost its prominence as time passed and much of Varhamihir’s works were not found to support this complex system.
The reason for popularity of Vimsottari Dasa system, which is calculated from position of moon is its accuracy in predicting events.
The reason behind chosing only moon’s position in a horoscope and leaving other planets and even lagna’s position can be explained as : Moon is fastest moving planet and it controls our mind and thoughts which are responsible for transfer of karma from one life to other along with soul.
So based on mind controlling moon, we carry our past life karma and face its consequences in this life.
The zodiac (360 degrees) is divided into 12 parts(each approximately 30 degrees) and 27 constellations (each constellation spanning 13′-20″) and a group of 3 constellations is owned by a planet based on its characteristics.
For example : Aswini, Magha, Moola – KETU, Bharani, Poorvaphalguni(pubba), Poorvashada – VENUS etc.
Since moon is primary factor for computing Dasa timings, sage Parasar chose the first segment of zodiac , which comprises of Aries to Cancer(owned by moon) as first 120 degrees.
Also moon owns 4th house(cancer) of zodiac, which represents our home, mother and comforts.
So, earth and moon are inseperable.
Next, Sun is father of entire zodiac as he only illuminates all other planets.
Leo sign owned by Sun is just east of Cancer-Moon-Earth.
Both Earth and Moon does not have their own light and depend on Sun.
So, Sun-Moon-Earth are inseperable.
Sun owns 5th sign Leo is zodiac and sun+moon combination is 4+5=9, which is useful to compute Dasa division.
Since each planet is given ownership of 2 signs in zodiac but only Sun and Moon are owning one sign each. Thats why the combined grouping of Sun and Moon is considered.
Guidelines to compute Vimsottari Dasa System
1. Parasar realised the sign values of all planets are 2 , except Sun and Moon, which own only 1 sign each
2. Natural Zodiac Signs are Mars owning 1 and 8(aries and scorpio), Moon 4(cancer), Sun 5(Leo), Venus 2 and 7(taurus and libra), Mercury 3 and 6(gemini and virgo), Jupiter 9 and 12(sagittarius and pisces), Saturn 10 and 11(capricorn and aquarius).
Total sign value of each planet will be 9(number of planets) except for sun and moon.
So their united value(4+5) is considered as united owner of Cancer and Leo.
This is explained as :
a) Mars , 1+8 = 9
b) Venus, 2+7 = 9
c) Mercury, 3+6 = 9
d) Moon and Sun as one unit, 4+5 = 9
e) Jup 9+12 = 21 , But maximum zodiac signs are 12, so subtract 12 from 21
21 – 12 = 9
f) Saturn 10+11 = 21 , 21-12 = 9
g) Rahu and Ketu have no ownership of signs but their value will be determined from their moola trikona signs.
Rahu’s moola trikona is Aquarius(kumbha) and Ketu’s moola trikona is Leo(Simha).
3. To determine the quantum of Dasa time period, counting should be from Moon sign or Sun sign individually or from both jointly when needed.
4. Because Dasa system is based on constellation, its value = 1 should be added to the count total.
5. To conclude on whether counting should be towards east or west side, its better to chose to count towards a planet’s moola trikona sign.
6. So, from Taurus to Libra are in inner-group(east signs) and from Scorpio to Aries are in outer group(west signs) .
That means Venus, Mercury, Moon, Ketu are is east group and Mars, Jupiter, Saturn, Rahu are in west group.
Sun belongs to both groups as its the lone illuminator.
Calculations Part
1. Sun Dasa :
a) Natural sign value of cancer-moon : 4
b) No. of Sun owned Sign : 1
c) No. of sun owned constellation-krittka : 1
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Total : 6 points or years
2. Moon Dasa :
a) Natural sign value of Leo-sun : 5
b) distance between cancer-moon
and Taurus(moola trikon of moon)
westward count : 3
c) No. of Moon owned signs : 1
d) No. of Moon-const-Rohini : 1
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Total : 10 points or years
NOTE: In case of Moon, sun’s natural sign is considered and vice-versa showing that both are inseperable and are one unit.
3. Mercury Dasa :
a) Combined sign value of Gemini+Virgo(3+6) : 9
b) Distance between cancer-moon and
Virgo-Kanya eastward count : 3
c) Distance between cancer-moon and
Mithuna-Gemini westward count : 2
d) No. of Mercury owned signs : 2
e) No. of Mercury-const-Aslesha : 1
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Total : 17 points or years
4. Venus Dasa :
a) Combined sign value of Taurus+Libra(2+7) : 9
b) Distance between cancer-moon and
Libra-Thula eastward count : 4
c) Distance between cancer-moon and
Taurus-Vrishabh westward count : 3
d) No. of Venus owned signs : 2
e) No. of Venus-const-Bharani : 1
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Total : 20 points or years
5. Mars Dasa :
Here combined value of Mars owned signs is 9 which is greater than its total Dasa years, which is 7.
So, we count from moon to its one natural sign or from sun to its other sign.
a) Distance between cancer-moon and
Aries-Mesha westward count : 4
b) No. of Mars owned signs : 2
c) No. of Mars-const-Mrigasira : 1
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Total : 7 points or years
(or)
a) Distance between Leo-Sun and
Scorpio-Vrishchik eastward count : 4
b)No. of Mars owned signs : 2
c) No. of Mars-const-Mrigasira : 1
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Total : 7 points or years
Here combined value of Mars signs is not considered because Mars is said to be born from earth itself, so directly its distance from moon and sun is considered, treating mars to be similar to earth.
6. Jupiter Dasa :
NOTE : Combined sign value of jupiter is greater than 9, so again we discard that total and count its signs distance from sun and moon only.
a) Distance between cancer-moon and
Saggi-Dhanu eastward count : 8
b) Distance between cancer-moon and
Pisces-Meena westward count : 5
c) No. of Jupiter owned signs : 2
d) No. of Jupiter-const-punarvasu : 1
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Total : 16 points or years
(or)
a) Distance between leo-sun and
Pisces-Meena westward count : 8
b) Distance between leo-sun and
Saggi-Dhanu eastward count : 5
d) No. of Jupiter owned signs : 2
e) No. of Jupiter-const-punarvasu : 1
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Total : 16 points or years
7. Saturn Dasa :
NOTE : since saturn is known as son of SUN, only natural combined value of sun+moon(4+5=9) is taken
a) combined sign value of sun+moon or combined
sign value of capri+aqua(10+11=21, 21-12(signs)=9) : 9
b) Distance from Leo-sun to Aqua-Kumbha(both ways) : 7
c) No. of Saturn owned signs : 2
d) No. of Saturn-const-pushyami : 1
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Total : 19 points or years
(or)
a) combined sign value of sun+moon or combined
sign value of capri+aqua(10+11=21, 21-12(signs)=9) : 9
b) Distance from Cancer-Moon to Capri-Makara
(both ways) : 7
c) No. of Saturn owned signs : 2
d) No. of Saturn-const-pushyami : 1
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Total : 19 points or years
8. Rahu Dasa :
NOTE : Moola trikona of Rahu is Aquarius-Kumbha. Since Rahu and Ketu doesn not posess any sign of their own, then signs owned by their moola trikona owner qualify.
So, since Rahu’s moola trikona sign aquarius is owned by saturn, its other sign Makara-capricorn is also qualified and it is considered to own 2 signs
a) Combined values of sun and moon : 9
b) Distance from Cancer-Moon to Aqua-Kumbha
west-ward or Leo-Sun to Capri-Makara east-ward : 6
c) No. of signs qualifying for Rahu : 2
d) No. of Rahu-const-Arudra : 1
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Total : 18 points or years
9. Ketu Dasa :
NOTE : Moola trikona of Ketu is Leo-Simha owned by SUN.
Since Sun doesn’t own any other sign, so only 1 sign qualifies for Ketu and only natural sign value of Sun is considered but not combined sign value of sun+moon.
a) Natural Sign value of Sun-Leo : 5
b) No. of signs qualifying for Ketu : 1
c) No. of Ketu-const-Aswini : 1
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Total : 7 points or years
Thus the total life span of 120 years (as defined for a human in kaliyug by sage parasar) is unequally divided as Sun=6, Moon=10, Mars=7, Mercury=17, Jupiter=16, Venus=20, Saturn=19, rahu=18, Ketu=7 and events are distributed based on their positions and inter-relations with each other, which are again based on past lives karma.
Conclusion :
We cannot conclude that this might be the only process used by Sage Parasar for formulating the unequal Vimsottari Dasa system, but it could be one of the leads towards his great work which was lost over a long period of 4500 years time, since he worked on this.