Treasures, Mohini, and the Origin of Eclipses

With the poison contained, the churning continues and yields a sequence of divine treasures in turn: the wish-fulfilling cow Kamadhenu, the goddess of fortune Lakshmi, who chooses Vishnu as her consort, and the divine physician Dhanvantari, who rises at last bearing the pot of amrita itself. When the amrita finally appears, the asuras seize it and a struggle for possession breaks out; Vishnu takes the form of the enchanting maiden Mohini, distracts and beguiles the asuras, and while distributing the nectar contrives to give it only to the devas, securing their victory and immortality.

One asura, Rahu, disguises himself among the devas and manages to drink a portion of the nectar before the sun and moon gods notice and alert Vishnu, who beheads him with his discus before the amrita can pass fully down his throat. Because the nectar had already reached his head, that portion becomes immortal even though his body does not, and the severed head, Rahu, and the still-mortal body, now called Ketu, are given a place in the heavens as the cause of eclipses, said to periodically swallow the sun or moon in revenge as they pass through their positions in the sky. The episode is one of the central cosmogonic events of Puranic Hinduism and a frequently depicted scene in temple sculpture across South and Southeast Asia.