Evidence pointing toward the existence of an undiscovered ninth planet in the solar system may actually indicate our ideas of gravity are incorrect. Such is the conclusion of two scientists who ...

Far beyond Neptune, something heavy appears to be tugging on the outer solar system, bending the paths of distant icy worlds in ways gravity alone should be able to explain. Planet 9, still invisible ...

Could data pointing toward a mysterious planet at the edge of the solar system actually suggest it's time to revisit our theory of gravity? When you purchase through links on our site, we may earn an ...