A New Planet? Perhaps. What Does The Name “Tyche” Mean? Published February 24, 2011 For years, scientists have been on the hunt for a mysterious “Planet Nine” that may exist in our solar system with a massive orbit of thousands—or even millions—of years. In 2011, a provocative hypothesis posed by a duo of planetary astronomers from the University of Louisiana-Lafayette named its version of this mysterious planet Tyche. They proposed a planet estimated to be four times the size of Jupiter was 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. Who was Tyche? 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. Is there a “Planet Nine”? 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. Unfortunately for Tyche, a 2014 search ruled out the possibility this particular planet exists. However, scientists are still searching for that mysterious “Planet Nine” (sorry Pluto, some of us still remember you!)—and we’re sure its name will be exciting once it’s found. 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.