In 1930, an astronomer named Clyde Tombaugh discovered a tiny, planet-like object that orbited farther out than any previously known celestial body. The discovery would for a time become known as the solar system’s ninth planet, Pluto, named after the Roman god of the underworld. Now considered a dwarf-planet, it is no longer considered the ninth planet ever since a 2006 reevaluation of what scientists consider a planet.
While Pluto may no longer be included with the eight major planets, it is the first major orbiting object of the Kuiper Belt. This far distant group of orbiting dwarf planets, or plutoids, make up some of the farthest known objects that directly orbit our own star. They include the slightly larger Eris, Pluto’s moon Charon, the ellipsoid Haumea, and the more recently nicknamed Ultima Thule. These TNOs (trans-Neptunian objects) were studied by a deep space probe in the New Horizons mission. Launched in 2006, this probe is where many of the striking, popular images of Pluto come from.
The dwarf planet is known for its freezing temperatures, odd orbit, and its previous status as a planet as well as the controversy around it’s reclassification. It orbits the Sun from almost 4 billion miles away, an orbit which actually intersects and brings the ice dwarf in front of the next closest body, Neptune. Since its discovery, the dwarf planet has yet to complete a full orbit, which takes 248 earth years to complete. The icy surface of Pluto is a chilling -360 degrees Fahrenheit. Pluto continues to fascinate and intrigue scientists and the public alike.
