A massive new planet in our solar system named Tyche? Maybe. But what does “Tyche” mean?

There may be a new planet joining the solar system. A provocative hypothesis posed by a duo of planetary astronomers from the University of Louisiana-Lafayette includes the existence of the planet Tyche: a ninth planet estimated to be four times the size of Jupiter located somewhere at the outermost reaches of the solar system. It’s hard to know what is more enjoyable: stories about planets themselves or the meaning behind their names. NASA can handle the astronomy; here’s the meaning behind the name.

Tyche (pronounced tayh-kee) is derived from the Greek word for “providence, fortune” and the Roman “fortuna.” It also refers to the ancient Greek goddess of spirit and fortune – a tutelary deity that oversees the destiny of a city. The Greek historian Polybius believed that when no direct cause could be identified for floods, drought or frosts, the blame fell on Tyche’s shoulders. A capricious dispenser of both good and ill will, Lady Luck giveth and taketh away.

(If you think this is a strange name, consider the one given to a mysterious green blob in outer space: Hanny’s Voorwerp. Learn the source of that moniker, here.)

The daughter of the Titans Oceanus and Tethys, Tyche is often depicted holding a large cornucopia that represents good luck and fortune and from which an abundance of coins fall. She also holds a rudder, helping her to guide and conduct the fates of the world. Finally, a ball completes her regalia, representing the unsteadiness of any given fortune.

Tyche’s benevolent sister and nemesis was, well, Nemesis: the goddess of retribution and indignation. An avenging goddess, Nemesis is regarded as the balancer of fortunes handed out by Tyche. Most interestingly, astronomers chose the name Tyche because the discovery of this new celestial body counteracts a once held-hypothesis that a solar object named Nemesis is responsible for regular, repeated extinctions on Earth.

Mythology is such a pervasive source of names in our culture that many of them probably escape your attention. For example, who is the one-armed God that Tuesday is named for? Or the comely Norse goddess that is Friday’s namesake? Find out here.