In Greek mythology, Merope is one of the seven Pleiades, daughters of Atlas and Pleione. Alone among her sisters she married a mortal — Sisyphus of Corinth — and bore him Glaucus and other sons; tradition makes her star the faintest of the cluster, the "lost Pleiad." Distinct from other Meropes (including Messenian and Chian figures in the atlas).
Adapted from Wikipedia, "Merope (Pleiad)" · CC BY-SA 4.0
I.Among the Pleiades
With Maia, Electra, Taygete, Celaeno, Alcyone, and Sterope, Merope belongs to the seven sisters whom Zeus transformed into the Pleiades — whether to escape Orion's pursuit or after an earlier change into doves. They appear as companions of Artemis in some tellings and as caretakers of the infant Dionysus in others.
Only six Pleiades are easily visible to the naked eye. Ancient myth explained Merope's dimness by her shame at wedding a mortal while her sisters bore children to gods; modern star naming does not always match that ranking (Asterope is fainter among the catalogued stars).
II.Marriage to Sisyphus
Merope's consort is Sisyphus; their children include Glaucus (father of Bellerophon in common stemmas), Ornytion (Porphyrion), Thersander, and Almus. Through Glaucus she anchors the Corinthian royal line to the Atlantid sky-sisters.
Homonym care: the atlas id merope-pleiad is this Pleiad. Other nodes (e.g. merope-messenia, merope-chios) are different women of the same name.