(523794) 2015 RR245
is a large trans-Neptunian object of the Kuiper belt in the outermost regions of the Solar System. It was discovered on 9 September 2015, by the Outer [Solar System Origins Survey] at Mauna Kea Observatories on the Big island of Hawaii, in the United States. The object is in a rare 2:9 resonance with Neptune and probably measures somewhere between 500 and 900 kilometers in diameter.
Discovery
A first precovery of was taken at the Cerro Tololo Observatory in Chile on 15 October 2004. It was first observed by a research team led by Michele Bannister while poring over images that the Canada–France–Hawaii Telescope in Hawaii took in September 2015 as part of the Outer Solar System Origins Survey, and later identified in images taken at Sloan Digital Sky Survey and Pan-STARRS between 2008 and 2016. The discovery was formally announced in a Minor Planet Electronic Circular on 10 July 2016.Numbering and naming
This minor planet was numbered by the Minor Planet Center on 25 September 2018. As of 2025, it has not been named [minor planets">List of named minor planets (numerical)">named [minor planets (numerical)|named].Orbit and classification
As of 2018, has a reasonably well defined orbit with an uncertainty of 3. It orbits the Sun at a distance of 33.8–128.6 AU once every 731 years and 6 months. Its orbit has an eccentricity of 0.58 and an inclination of 8° with respect to the ecliptic.is among the most distant known Solar System objects. As of 2018, it is 63 AU from the Sun. It will make its closest approach to the Sun in 2093, when it will reach an apparent magnitude of 21.2.