One observing the planetary line-up these days, would note that it could give rise to the Kalasarpa Yoga whenever the fast moving Moon enters the Rahu – Ketu axis. 

How Kalasarpa Yoga is formed
Most students of Astrology may know that the Kalasarpa Yoga is formed whenever all the seven planets are placed between Rahu and Ketu or between Ketu and Rahu. To give a more detailed definition of Kalasarpa Yoga given in a classical work: if in a horoscope all the seven planets are between Rahu and Ketu in relation to any of the Houses, then the yoga thus formed is called Kalasarpa Yoga.

Evil effects
Kalasarpa Yoga is considered a very evil yoga and its effects are: The native will not enjoy mental peace even if he possesses high status, money, power and prosperity. Native may rise to a very high position from a very humble beginning, but he may have to suffer humiliation on account of a penalty imposed by the government.

Redeeming aspects
However, Kalasarpa yoga has its redeeming features. As in the case of Neecha bhanga, Kalasarpa bhanga too gives rise to a very auspicious yoga. Besides, there are a number of planetary combinations that nullifies the Kalasarpa yoga. Further, it has been established through research done by competent astrologers that the very presence of Kalasarpa yoga in a Natal Chart is an indication that the native would attain greatness and prominence in some field. Another positive factor is that Astrology acknowledges human will power is superior to all other powers and man is capable of warding off any pre-determined Karmic effect through the use of his free will.

Among the many famous and successful people in the world known to have had Kalasarpa yoga in their birth charts are Jawaharlal Nehru, Abraham Lincoln, Margaret Thatcher, Zulfikar Ali Bhutto and Sachin Tendulkar. 

Positions of planets in the Zodiac 
We know that the planets like Mercury, Mars and Venus that orbit close to the Sun are found in Rashis close to that of the Sun as they are found moving constantly in longitudes close to the Sun. As a matter of fact, we often find both the Sun and Mercury, the planet closest to the Sun, occupying the same sign in a horoscope. However, the distant planets like Jupiter and Saturn are often found moving in Zodiacal signs far away from that of the Sun.

Reason for the formation of Kalasarpa Yoga 
However, these days Jupiter and Saturn too are found in longitudes close to that of the Sun. In fact, Saturn is moving these days in Sagittarius in the company of the Sun and Venus only a few degrees apart from one another and Mercury too will join them on January 6 giving rise to Chatur-graha Samyoga or a four planet combination.

Meanwhile, the other distant planet Jupiter is moving in Libra sign along with Mars, close behind the Sun and the other planets in the Zodiacal circle. As for the Moon it is the fastest moving planet in the Zodiacal circle which takes only about 54 hours to traverse one sign in the Zodiac. As a result of the six of the seven planets clustering in signs close to the sign where the Sun is placed, the chances of their falling within the Rahu – Ketu axis have arisen. By the way, these days Rahu is passing through Cancer and Ketu through the Capricorn sign.

Current configuration of planets leading to the formation of Kalasarpa Yoga
Moon which exited from the Rahu – Ketu axis at   20.02 hours on December 20 for the last time will re-enter the axis by beginning its passage in the Leo sign at 03.56 on January 05. So all the seven planets including the Moon will remain hemmed in between Rahu in Cancer and Ketu in Capricorn until Venus moves into Capricorn to be conjunct with Ketu at 14.45 hours on January 13. This means children born between December 20 and January 13 will come under the malefic influence of Kalasarpa Yoga. 

However, there are planetary combinations that nullify this Kalasarpa Dosha. Kalasarpa Bhanga Yoga can arise when:

Graha Malika Yoga is present. When planets are placed continuously in five consecutive signs this yoga can occur.

Rahu and Ketu are aspected by or conjoined with their dispositors. (In the present context, Moon and Saturn as Cancer where Rahu is placed is owned by Moon and Capricorn where Ketu is placed is owned by Saturn)

 Rahu or Ketu is involved in forming any auspicious yoga
Yogakaraka or yoga forming planets are with Rahu or Ketu. 
The 9th House is strong and is aspected by Yogakaraka

Rahu occupies its own Nakshatra (constellation) Ada, Saa or Siyawasa.
The 9th House or the 9th lord is aspected by or associated either with Mars or Saturn.
The Ascendant is owned by Mars or Saturn or these planets influence the Ascendant or its lord
The dispositors of Saturn and Mars are in quadrants from each other or in Dwirdwadasa positions.   
            
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