A potential dwarf planet has been discovered in the outer reaches of our solar system, orbiting beyond Neptune. Its presence there challenges the existence of a hypothetical body known as Planet 9 or Planet X.
Sihao Cheng at the Institute for Advanced Study in Princeton, New Jersey, and his colleagues first detected the object, known as 2017 OF201, as a bright spot in an astronomical image database from the Victor M. Blanco Telescope in Chile.
