structural:expansion, quality:correction
Crescent

For the representation of the Moon, especially its lunar phases, the crescent (🌙) has been a recurring symbol in a range of cultures since at least 3,000 BCE (Nebra sky disc) or possibly earlier with bull horns dating to the earliest cave paintings at 40,000 BP. In writing systems such as Chinese the crescent has developed into the symbol 月, the word for Moon, and in ancient Egyptian it was the symbol 𓇹, meaning Moon and spelled like the ancient Egyptian lunar deity Iah, which the other ancient Egyptian lunar deities Khonsu and Thoth were associated with.

Iconographically the crescent was used in Mesopotamia as the primary symbol of Nanna/Sîn, the ancient Sumerian lunar deity, who was the father of Inanna/Ishtar, the goddess of the planet Venus (symbolized as the eight pointed Star of Ishtar), and Utu/Shamash, the god of the Sun (symbolized as a disc, optionally with eight rays), all three often depicted next to each other. Nanna/Sîn is, like some other lunar deities, for example Iah and Khonsu of ancient Egypt, Mene / Selene of ancient Greece and Luna of ancient Rome, depicted as a horned deity, featuring crescent shaped headgears or crowns.

The particular arrangement of the crescent with a star known as the star and crescent (☪️) goes back to the Bronze Age, representing either the Sun and Moon, or the Moon and the planet Venus, in combination. It came to represent the selene goddess Artemis, and via the patronage of Hecate, which as triple deity under the epithet trimorphos / trivia included aspects of Artemis/ Diana, came to be used as a symbol of Byzantium, with Virgin Mary (Queen of Heaven) later taking her place, becoming depicted in Marian veneration on a crescent and adorned with stars. Since then the heraldric use of the star and crescent proliferated, Byzantium's symbolism possibly influencing the development of the Ottoman flag, specifically the combination of the Turkish crescent with a star, and becoming a popular symbol for Islam (as the hilal of the Islamic calendar) and for a range of nations.