In Greek mythology, Hesperus (Greek Ἓσπερος Hesperos), the Evening Star an Eosphorus (Ηωσφόρος Eosphoros "dawn-bearer"; also Φωσφόρος Phosphorus, Lucifer "light-bearer", Iubar), the Morning Star are sons of the dawn goddess Eos (Roman Aurora). Hesperus' father was Cephalus, a mortal, while Eosphoros' was the star god Astraios. Hesperos Roman equivalent was Vesper. (cf. "west", direction of sunset/dusk/evening star and "east", direction of morning star/dawn/sunrise). Venus shines very bright because its dense atmosphere of carbon dioxide reflects the sunlight extremely well.