Sterope (also Asterope) is one of the Pleiades, a daughter of Atlas and Pleione. Apollodorus makes her the wife of Oenomaus of Pisa; Hyginus instead calls Oenomaus the son of Ares and Asterope daughter of Atlas. She is tied to the Pelops–Hippodameia cycle at Olympia.
Adapted from Wikipedia, "Sterope (Pleiades)" · CC BY-SA 4.0
I.Among the Pleiades
Sterope is listed with the other Atlantides in Apollodorus' catalogue of the Pleiades (Bibliotheca 3.10.1). Variant spelling Asterope appears in Hyginus and some astronomical lists; both names point to the same Pleiad in standard handbooks.
II.Oenomaus
Apollodorus says Sterope was married to Oenomaus, the king who challenged suitors of his daughter Hippodameia to a chariot race. Pausanias describes the east pediment of the temple of Zeus at Olympia with Oenomaus and Sterope among the figures of the Pelops myth (Description of Greece 5.10.6–7; cf. 6.21.7 on related local lore).
Hyginus Fabulae 84 makes Oenomaus the son of Mars (Ares) and Asterope daughter of Atlas — so Sterope/Asterope is mother rather than wife in that branch. The contradiction is a standing mythographic fork, not a modern error.
III.Homonyms
Other Steropes exist in Greek myth (including a Cyclops Steropes). The Pleiad is identified by Atlas parentage and the Oenomaus connection at Pisa–Olympia.