Question: how rahu and ketu formed?
Answer: Mohini, the female avatar of Vishnu, started distributing Amrit to the Devtaas. ... Vishnu as Mohini cut off Svarbhanu's head with Sudarshan Chakra. Rahuketu could not die but his head was separated from his body and his head came to be known as Rahu, while his body came to be known as Ketu.