So, the story goes back to the event of Samudra Manthan. Gods and Demons took part in Samudra Manthan in search of Nectar which can make them immortal. Besides Nectar, many other things emerged from the sea including poison. Poison was consumed by Lord Shiva and Parvati kept her hand on Shiva's throat so that poison never passed below throat. That's why his throat turned blue and Lord Shiva was called Neelkantha.
Then when nectar emerged after Samudra Manthan, Demons tried to capture it and drink all by themselves. Gods requested Lord Vishnu to help them. Lord Vishnu took the incarnation of beautiful Mohini. By looking at the beauty of Mohini, Demons were mesmerized and forgot about nectar. Same Mohini took the nectar pot from Demons and started serving nectar to the Gods.
One of the Demons named Rahuketu was master of creating illusions. He used his art and took the appearance of a God and set in the group of Gods, so that Mohini ends up in serving nectar to him also, thinking him as a God. Now, any act of illusion can be nullified by illuminated beings. Who were the illuminated beings among Gods? Sun and Moon. Sun and Moon realised that Rahuketu has taken form of a God and thereby trying to consume the nectar. They informed Mohini. By that time Mohini had served the nectar to the demon. Mohini came back into the real Vishnu incarnation and threw the Sudarshan Chakra towards Rahuketu. Sudarshan Chakra cut Rahuketu's head, but by that time, nectar had entered the throat of the Demon. Hence, the head had become immortal. Now, this head portion is renamed as Rahu and the body portion is Ketu.
Another thing is that when the head portion was cut off, it saw Sun and Moon sitting behind Vishnu. Rahu realised that it is these 2 fellows who complained against him. That's why Rahu and Ketu keeps enmity against Sun and Moon. This is also the reason why Rahu and Ketu eclipses Sun and Moon only. They never eclipse any other planet. So, if we really want to see Rahu and Ketu in sky, we should look at the north and south points of Sun or Moon when these planets go into eclipse. That's why Rahu is called North Node of the Moon and Ketu is called South Node of the Moon. This is also the reason why in any horoscope Rahu and Ketu are always at 180* from each other. Like in the horoscope attached, Rahu is at 3rd house and Ketu is at 9th house. Now, if Rahu moves to 4th house, Ketu will move to 10th house. They are always at 180* from each other.
Vishal S Saxena – Astrologer
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