When the Greeks learned to recognise the five planets known in antiquity, they gave them names derived from their character. Venus, whose brightness Homer had already celebrated, was called "Herald of the Dawn" ('Εωбϕóρος) or "Herald of Light" (фωбφóρος) or on the other hand "Vespertine" ("Εбπερος), according as she was considered as the star of the morning or that of the evening (the identity of these two being not yet recognised). Mercury was named the "Twinkling Star" (Στíγßων), Mars, because of his red colour, the "Fiery Star" (Άῦρóεις), Jupiter the "Luminous Star" (Φαέθων), Saturn the "Brilliant Star" (Φαíνων), or perhaps, taking the word in another sense, the "Indicator." Now, after the fourth century other titles are found to supersede these ancient names, which are gradually ousted from use.
The planets become the stars of Hermes, Aphrodite, Ares, Zeus, Kronos, ('Ερμοŭ, 'Αϕροδϭτηζ Ϻτλ. ἀбτἧρ). Now this seems due to the fact that in Babylonia these same planets were dedicated respectively to Nebo, Ishtar, Nergal, Marduk, and Ninib. In accordance with the usual procedure of the ancients, the Greeks substituted for these barbarous divinities those of their own deities who bore some resemblance to them. Clearly exotic ideas, the ideas of Semitic star-worship, have come in here, for the ancient mythology of Hellas did not put the stars under the patronage of the Olympians nor establish any connection between them. Thus the names of the planets which we employ to-day, are an English translation of a Latin translation of a Greek translation of a Babylonian nomenclature.