Nothing happens by itself. Everything happens by Cause. The Universal Law of Cause & Effect, the Law of Retribution, the Law of Nemesis, the Law of Action & Reaction is the grand Law of Causation, known to the philosophers as the Universal Law of Karma. Who can transcend the Universal Law ?
The system in VA which corresponds to this Universal Law is called the Dasa System, which is made up of planetary periods and subperiods and which extends to 120 years. Dasa is translated as the period of directional influence of the ruling planet. Inevitable effects are to be judged from Dasa ( Dasa prabhedena Vichinthayeth Dridam). Astrology is based on this Universal Law of Cause and Effect .
In his ignorance, Man transgresses the eternal Laws of Nature & wonders when her inexorable penalties are exacted. There is a mathematical law behind this physical Universe, which is conditioned in Space, Time & Causality. All events are connected by Time, all places are connected by Space & all effects are connected by Cause in the Space-Time-Causality equation.
Planets have got dualistic role and always the negative aspect of the ruling planet must be taken into consideration & divine remedial measures must be resorted to overcome the minus points of the Dasa ruler.
Philosophically Dasa represents the Prarabda Karma (the inevitable punishment imparted by Nature for a deed done with malice aforethought ) of the native and the ineluctable effects he/she has to undergo during the planet's reign.
There are many Dasa systems, the prominent among them being Vimshottari Dasa System. Vimshottari means 120 and this is a 120 year cycle. Every planet is given a period in sequential order of stars in the Sidereal Zodiac. For instance, South Node ( Ketu ) is assigned a period of 7 years & the South Node rules the first constellation Beta Arietis (Aswini ). The ruler of the next constellation of 41 Arietis ( Bharani ), Venus, gets 20 years. Sun gets 6 years, Moon 10, Mars 7, North Node ( Rahu ) 18, Jupiter 16, Saturn 19 & Mercury 17. This 120 year system is the most widely used. There are other systems like the Kala Chakra Dasa System, based on the Signs of the Sidereal Zodiac, which are also used.
There is a rule that if the Moon's Navamsa dispositor is strong, the Kala Chakra Dasa should be used. ( Kala Chakra Dasagneyam Chandramsheshe Balanvithe ). If not, the 120 year cycle or Vimshotthari can be be used.
There are many astrologers who base their predictions on other systems of predictions. There are actually 3 major systems of prediction in V A.
1) The Vimshottari or Udu Dasa System of 120 years.
2) The Transit of Gochara System based on Planetary Transits.
3) The Ashtakavarga System.
The Transit influences are always subordinate to the Directional influences. This is exemplified by the statement " Dasa Prabhedena Vichinthayeth Dridam " ( Dasa deals with ineluctable effects ). Transit influences are caused by non-Prarabdha Karma ( Dridadridam cha Ashtakavarga Gocharai ).
The accumulated Karma of the individual is called Sanchitha Karma. The Karma which is about to come is called Agami and the Karma for which inevitable punishment is necessary is called Prarabda Karma. It is this Prarabda Karma, which needs ineluctable punishment, which is represented by Dasa or the Planetary Period of Directional Influence.
In order to know whether a Dasa is beneficial or not, one should study the strength of the Dasa ruler. If the Dasa ruler is a functional benefic ( owner of a trine or angle ) in the chart & if he be well posited, one can surmise that the directional influences will be benefic. If on the other hand, the Dasa ruler is a functional malefic and badly positioned in the natal chart, the directional influences can be very adverse indeed. Aspects from other planets should also be considered. Planets in cuspal degree are devoid of strength. So are combust planets and planets weak in the Navamsa chart. It is always better to know the strength of the planet via Shad Bala ( the sixfold source of planetary strength ) and apply the principle " Balavan Ishtam Kuruthe, Balaheeeno Viparya ". ( a powerful planet will do only good and weak planet will do harm ).
The balance Dasa at the time of birth is ascertained by observing the longitude of the Moon and the distance traversed by the Moon in that particular constellation. If the Moon has traversed, say 75%, the balance 25% will be the dasa balance at birth. A constellation is 800 minutes or 13 degrees 20 minutes of arc. For example, if the Star is Pushya ruled by Saturn and if the Moon has traversed 600 minutes of arc in the 800 minutes of Pushya, the balance Dasa can be calculated by the formula
Balance Dasa at birth = 19 years of Saturn Dasa * (800-600)/800
Vimshottari Dasa in Natal Astrology
|North Node ( Rahu )||18|
|South Node ( Ketu )||7|
Trisphuta Dasa in Horary Astrology
As important as Vimshottari is to Natal Astrology, so is Trisphuta Dasa to Horary Astrology. The Ascendant rules Life, the Moon the Body & Gulika , the satellite of Saturn, Death. The sum of these 3 longitudes is called the Triune Longitude or Trisphuta. Since Horary Astrology deals only with the current effects for one year, the span of Trisphuta Dasa is one Year. In Horary Astrology, the numbers assigned to the planets in terms of years is multiplied by 3 to get days ruled by the planet. So Sun gets 18 days, Venus 60 days, Moon 30 days, Mars 21 days, Rahu 54 days, Jupiter 48 days , Saturn 57 days, Mercury 51 days, Ketu 21 days etc. Here, instead of the longitude of the Moon, the longitude of Trisphuta ( Triune Longitude ) should be taken into consideration.
Balance Dasa at Birth = 57 days of Saturn Dasa * (Space-Long Trisphuta)*60/800
|North Node ( Rahu )||54|
|South Node ( Ketu )||21|