The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...

Even at a glance, the planets in our solar system are wildly diverse. Huge and small, airless and densely packed with ...

Astronomers have discovered icy rocks in the outer solar system that seem to defy the laws of physics, suggesting the potential existence of a hidden ninth planet. In this video, the lead researchers ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...