related article:
Distant new world may point to undiscovered planets in solar system
Today’s discovery of dwarf planet 2012 VP113 suggests that many planet-sized worlds lurk undetected beyond the orbit of Pluto, maybe even a giant ‘Super Earth’
http://www.theguardian.com/science/across-the-universe/2014/mar/26/planets-solar-system-2012-vp113-dwarf-planet-super-earth