Kal Sarp Dosh

In ancient texts, there is no mention of Kal Sarp Yoga but in practical formation this Yoga gives its effects according to placement of Rahu. In Astrology, Rahu and Ketu are only nodes and they have no physical body. Rahu is known as head of dragon or snake and Ketu is the tale of snake. When all the planets come under Rahu Ketu axis, then Kal Sarp Yoga is formed.