Tyche is asteroid #258 and was discovered by (Karl Theodor) Robert Luther at the Düsseldorf-Bilk Observatory. Some people count Tyche to the Eunomia-family because Tyche resembles Eunomia in orbit and composition. Tyche would then be the second-largest asteroid in this Hirayama-family. Tyche however orbits at the very edge of the asteroid-family’s orbits and this is unlikely for the largest members. Hence other people think that Tyche must be an unrelated interloper.

Tyche is named after the Greek goddess Túkhē (Τύχη). Her name means luck. She is the daughter of Aphrodite and Zeus, but several other genealogies were, probably later, given to her too. Maybe the genealogy that Túkhē (Τύχη) is the daughter of Okeanos and Tethys is older and the original variant. Túkhē (Τύχη) got depicted with different attributes, sometimes a cornucopia, sometimes a steering wheel or a rudder or a wing or a sphere, sometimes she has the god of richness, the Greek Plutos (not to be confused with the Roman Pluto!), on her arm. Such variants were called Tychai and are rather typical for the Hellenistic period, the later period in Greek history, when Greece was already conquered by Rome. Túkhē (Τύχη) governed the destiny of cities. She could make cities prosper, but also bring floods, droughts, or (rather unusual in Greece) frosts. She was later more and more seen as personal fate, responsible for chance encounters, but also less and less personalized as a goddess.

Túkhē (Τύχη) is generally seen as the Greek version of the Roman goddess Fortuna. Because Túkhē (Τύχη) decides about destiny, she also must be a goddess of justice, at least an executor of divine justice. So it would make sense if Tyche is a member of the Hirayama-family Eunomia. Tyche then has the task to enforce the good order and stable society, which Eunomia represents and governs. Astrologers know two benevolent and two malevolent planets among the real planets, so Tyche can’t have a big say. She can perhaps by her relations with the other asteroids of the Eunomia-family within an astrological chart reveal why there is good luck or why there is bad luck.