Astraeus is a second-generation Titan, son of Crius and Eurybia, and a god of the dusk and of the starry sky; his Greek name means the starry one. His significance is genealogical: by Eos, the Dawn, he is the father of the four principal winds, Boreas the north wind, Notus the south, Eurus the east and Zephyrus the west, and, in Hesiod's account, of the stars of heaven, including the morning star. The pairing is neatly poetic: the god of the dusk and the goddess of the dawn together bring forth the winds that blow between night and day and the stars that appear as one fades into the other.
Astraeus has no cult and no narrative of his own; he belongs to the systematic cosmogony of the Theogony, which peoples the sky by making the natural phenomena of the heavens the children of named Titan powers. Astraeus's name and role made him a natural point of comparison for later poets discussing the dawn and the winds together; Roman writers occasionally connect him, loosely, with figures presiding over the western sky, though no independent Roman cult or clearly parallel deity is securely attested, and, like most of the second-generation Titans, his presence in ancient religion, as opposed to poetic genealogy, appears to have been negligible.