An international team of astronomers has discovered a new dwarf planet in our solar system just beyond the orbit of Neptune. According to a press release from the University of British Columbia, the dwarf planet is approximately 430 miles (700 km) in diameter, giving it about the same square footage as Montana. The planet, called RR245, is 120 times farther from the Sun than our own planet.
The tiny planet was discovered by the Canada-France-Hawaii Telescope on Maunakea, Hawaii. The telescope is being used in the ongoing Outer Solar System Origins Survey, an astronomical research project to observe and catalogue the outer reaches of our solar system. While this survey has found many objects in deep orbit around our Sun, this is the first one to be designated a dwarf planet.
Such a find has thrilled the astronomers working on this project, according to Brett Gladman, the Canada Research Chair in planetary astronomy at UBC:
Finding a new dwarf planet beyond Neptune sheds light on the early phases of planet formation. Since most of these icy worlds are incredibly small and faint, it’s exciting to find a bright one that is easier to study, and which is on an interesting orbit.
The new dwarf planet is made unique in our solar system by its incredibly long orbit. RR245 makes a trip around the sun only once every 700 Earth-years, giving it one of the longest known orbits of any object in our solar system. Due to its long orbit, the exact path RR245 takes through our solar system is still unknown, as is its exact size. Since the dwarf planet is so far away, it is difficult to ascertain its exact makeup and dimensions.
Dwarf planets such as RR245 formed in the early days of the solar system. As the larger planets formed, many dwarf planets were destroyed, pulled into orbits to become moons, or forced out of the solar system due to gravitational interference.
RR245 currently resides at quite some distance from the Sun; at the furthest point in its orbit, RR245 is roughly 12 billion kilometers away from the center of our solar system. In 2096, it will reach its closest point of 5 billion kilometers from the Sun.