Until a few years ago, scientists believed our Solar System contained nine planets. The discovery of a planet-like object called Eris in 2005 changed all that, leading to the creation of a new class of objects called dwarf planets. Now we have eight planets and an ever-growing family of dwarf planets. There are five official dwarf planets, and a large group of other objects believed to be dwarf planets that have not yet been designated as such. One of these is 28978 Ixion, also known as TNO Ixion (TNO is short for Trans Neptunian Object). Learn more:
– Ixion was discovered on May 22, 2001 by the Cerro Tololo Inter-American Observatory in Chile.
– Ixion is located in the region of space beyond the planet Neptune, known as the scattered disc. Its average distance from the Sun is about 40 Astronomical Units. One AU is equal to the distance between the Earth and the Sun — about 92,957,000 miles!
– It takes Ixion approximately 250 years to orbit the sun. Astronomers do not yet know how long it takes to rotate once on its axis. The body is classified as a plutiono because, like Pluto, it has an orbital resonance with the planet Neptune.
– Astronomers believe Ixion is about 400 miles in diameter, making it just over a quarter the size of Pluto.
– The surface of Ixion is moderately red and believed to be comprised primarily of water ice and tholins, molecules formed by the irradiation of simple organic compounds such as methane and ethane.
– Ixion was named for a Greek mythological figure who was cursed for slaying his father-in-law. The name was chosen in keeping with the tradition of naming planets after mythological deities.
– Ixion has no known moons.
– The average temperature on Ixion is a numbing -380° F!
– Ixion’s small size means that it has only a very thin atmosphere.
– Ixion can only be seen through very high-powered telescopes.