In 2004, scientists found Sedna, a potential dwarf planet beyond the belt, had a strange orbit around the sun that hinted another large mass was gravitationally pulling it. A 2014 study found a ...

For years, scientists have observed the Solar System’s outer reaches in search of a Planet Nine. While Pluto was demoted to dwarf planet status in 2006, some researchers believe an even larger ...

Opinions expressed by Forbes Contributors are their own. Jamie Carter is an award-winning reporter who covers the night sky. Computer simulations suggest that there is an undiscovered Earth-like ...