One of the earliest of all known creation accounts is Egyptian and associated with the god Atum, which scholars call the Heliopolitan Cosmogony. A cosmogony is a story of how the world came to exist. In this version of creation, the universe is originally an infinite, dark, watery expanse called Nun. Within this watery expanse, the god Atum essentially creates himself, and looks about for a place to stand. Atum finally stood on the primeval hill located at Lunu, an image deriving from the emergence of land after the annual Nile flood recedes. After finding a place to stand, Atum masturbates into the void and from his semen produces the first pair of gods, Shu (male) and Tefnut (female).