The Kaal Sarp Yoga is formed when all the planets are situated between Rahu and Ketu. According to Hindu mythology, Rahu is known as a snake and Ketu is its tail. Whenever there is the placement of all 7 planets between Rahu and Ketu then Kaal Sarp Yoga is formed. There are 12 types of Kaal Sarp Yogas depending on the placement of Rahu and Ketu in the 12 houses. The Kaal Sarp Yoga is again of two types, both ascending and descending. If all the 7 planets are eaten away by Rahu's mouth then it is ascending Kaal Sarp Yoga. If all planets are positioned in rear of Rahu then descending Kaal SarpYoga is formed.
Kaal Sarp Yoga is complete when all planets are situated between Rahu and Ketu. Moreover in line with the horoscope every time the mahadasha or antardasha of Rahu or Ketu comes then Kaal Sarp Yoga becomes more effective. Nevertheless, if in a horoscope few planets are between Rahu and Ketu but few planets are outside the axis of Rahu and Ketu then partial Kaal Sarp Yoga is created.
Contrary to popular belief the effects of this Yoga are not always malefic. Just having one of the 12 combinations described above does not mean that the native will invariably go through the results described above. The whole chart needs to be analyzed in order to come to a conclusion. In my experience following factors should be considered.
1. One must check the overall strength of the chart by looking at Lagna, Lagna lord, Moon and Sun. If the overall chart is strong this will not let the kaalsarpa yoga have any major negative influence. A weak chart on the other hand will not be able to protect the native.
2. Depending on the Rahu/Ketu position, determine which side of the axis has all planets. All the houses of the side which is totally empty will feel the effects of this yoga. The houses in which Rahu/Ketu fall will particularly determine the area of life which will be impacted negatively.
3. However if the lord of the houses falling on the empty side of the Rahu/Ketu are very well placed (Exalted, in Friend's house, in own house, aspecting their own house). Then those houses will not suffer that much and negative effect will be reduced to the factors attributed to those houses.
4. Vasuki, Padam, Mahapadam, Shankachood and Vishdhar Kaalsarpa generally do not give bad results if the overall chart is in a really bad shape. This is because of their association with 3rd, 6th and 11th house in which Rahu/Ketu are considered favorable.
5. If in D-9 chart Rahu/Ketu fall in 3rd, 6th or 11th house, then the effects are reduced.
6. One must check the constellations of Rahu/Ketu as well. If they fall in benefic constellations (if the lords are natural benefic planets) then they become more unfavorable.
7. Its impact will be more prominent during dasha and antardasha periods of Rahu and Ketu. This is very important point. If this yoga is very strong in one's chart, but the dasha does not operate till very late in his life, then it really does not affect the native that much.
8. It causes severe hardships when related with Sun and Saturn or the lords of the houses occupied by Sun or Saturn.
This yog is made in the horoscope because of previous birth karma. It is related to the "pitra lok". It is mainly divided into two groups:
"UDIT - when rahu is at the upper end
"ANUDIT (Vipreet)-when ketu is at the upper end
Anudit Kalsarp yogas are less severe than udit kalsarp yog but shanti of this yoga is also adviced by the astrologers.
How can Kaal Sarp Yoga affect you?
The native gets bad dreams and developes depression and this causes hurdles in gaining of wealth, bearing of children, causes disputes in marital life and may even cause death of the native. Besides native may suffer from diseases like heart ailment and ailment of eyes and ears. Placement of Rahu or Ketu, with the lumanaries i.e. Sun or Moon, causes their eclipse. It is called Grahan KalSarp yoga, which in Shastras is considered many times more malefic. These ill effects can be minimized with the remedies.