The Astronomical Journal is putting forward proof of an unseen entity in the far reaches of the solar system that is so massive it must certainly be a planet. This study was written by researchers Konstantin Batygin and Mike Brown from the California Institute of Technology, with Brown being the lead in the effort to reclassify Pluto.
Batygin and Brown developed their theory after examining objects in the (perhaps unexpectedly vast) Kuiper Belt, a circular area of small, icy objects beyond Neptune that encompasses Pluto and other dwarf planets such as Eris. They detected a collection of six Kuiper Belt objects that are grouped together, following peculiar elliptical paths that lead them outside of the solar system’s plane, where the eight recognized planets orbit. The chances of such an arrangement being purely coincidental are about one in 15,000, according to the researchers, though an alternative explanation could be the presence of a planet in the outer sections of the solar system, vast enough for its gravitational influence to affect the other objects.