In Greek mythology, Semele (Ancient Greek Σεμέλη), also called Thyone after her apotheosis, was the youngest daughter of Cadmus and Harmonia of Thebes and the mortal mother of Dionysus by Zeus. Tricked by a jealous Hera, she asked Zeus to appear in his full divine splendour and was destroyed by his lightning; Zeus rescued the unborn child and later raised Semele among the gods under the name Thyone.
Adapted from Wikipedia, "Semele" · CC BY-SA 4.0
I.Family
Semele was the youngest daughter of Cadmus, founder of Thebes, and Harmonia. Her sisters were Autonoë, Agave, and Ino; her brother was Polydorus. Through Cadmus she belonged to the Theban royal house that later suffered the Bacchic disasters recounted in Euripides' Bacchae.
By Zeus she was the mother of Dionysus. Ancient authors sometimes stress that Zeus was also her great-grandfather through the Cadmeid line, underscoring the extraordinary double birth of the god.
II.Mythology
Zeus loved Semele and visited her in secret. Hera, discovering the affair and Semele's pregnancy, disguised herself as an old nurse, sowed doubt, and persuaded the princess to demand that Zeus appear exactly as he appears to Hera. Bound by an oath on the Styx, Zeus came with thunderbolts; the mortal chamber could not endure his glory, and Semele was consumed by fire.
Zeus snatched the six-month foetus from the flames and sewed it into his thigh, whence Dionysus was later born — hence the epithet "twice-born." When grown, Dionysus descended to Hades, brought his mother up, and established her among the Olympians as Thyone. Variant traditions (Hyginus, Nonnus, and others) intertwine Semele's pregnancy with the Zagreus/heart-of-Dionysus cycle, but the incineration by Zeus's lightning remains the core Theban story.
Aeschylus wrote a lost tragedy Semele (or The Water Carriers). Herodotus, recounting Cadmus, places Semele many centuries before his own day; Roman religion identified the goddess Stimula with her.
III.Namesakes
The atlas id semele is the Theban mother of Dionysus. Later astronomical and cultural namesakes (including the asteroid 86 Semele) are modern labels derived from the mythic figure, not alternate identities of this character.