The ancient Mesopotamians regarded the sky as a series of domes (usually three, but sometimes seven) covering the flat Earth. Each dome was made of a different kind of precious stone. The lowest dome of heaven was made of jasper and was the home of the stars. The middle dome of heaven was made of "saggilmut" stone and was the abode of the Igigi. The highest and outermost dome of heaven was made of "luludānītu" stone and was personified as An, the god of the sky. The celestial bodies were equated with specific deities as well. The planet Venus was believed to be Inanna, the goddess of love, sex, and war. The Sun was her brother Utu, the god of justice, and the Moon was their father Nanna.