Scientists have discovered hundreds of new objects in the outer solar system using an instrument designed to probe an unexplained source of energy in the universe. The results reveal new insights about the mysterious expanse beyond Neptune, including the possibility that a massive undiscovered planet may be lurking in these dark outer reaches.

A team led by Pedro Bernardinelli, a postdoctoral researcher at the University of Washington, scanned the outer solar system for six years with the Dark Energy Survey (DES), a Chile-based astronomy program whose primary objective is understanding dark energy, an unknown force that's driving the accelerated expansion of the universe.