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 that meet the criteria to be dwarf planets but have not yet been designated as such. One of these is an oblong body known as 20000 Varuna, or TNO Varuna (TNO is short for Trans Neptunian Object). Learn more:
– Varuna was discovered on November 28, 2000, by Robert McMillan, an astronomer at the University of Arizona.
– Varuna is located in the region of space beyond the planet Neptune, known as the scattered disc. It has a near-circular orbit about 43 Astronomical Units from the Sun. One AU is equal to the distance between the Earth and the Sun — about 92,957,000 miles!
– It takes Varuna approximately 283 years to orbit the sun, and about three hours to rotate once on its axis.
– Astronomers believe Varuna is football-shaped and about 623 miles in diameter, making it about one fifteenth the diameter of Earth, one quarter the diameter of the Moon, and a third the size of Pluto.
– The surface of Varuna is believed to be rich in minerals, as well as small amounts of water and ice.
– Varuna is named after the Hindu god of oceans and immortality. The name was chosen in keeping with the tradition of naming planets after mythological deities.
– Varuna has no known moons.
– The average temperature on Varuna is a numbing -480 F!
– Varuna’s small size means that it has only a very thin atmosphere.
– Varuna can only be seen through very high-powered telescopes.