Astronomers propose a new hypothetical planet, Planet Y, beyond Neptune, based on observed orbital anomalies in the Kuiper ...

Yet actually finding Planet Nine, sometimes called Planet X, has eluded scientists for nearly a decade. But the hunt for the solar system's potential ninth planet may soon be coming to a close.

New discoveries of objects in the Kuiper Belt have also presented challenges for the Planet Nine theory. The latest is known ...

A mysterious new world may be hiding in the outer reaches of our solar system. According to arecent study published on arXiv ...

A new study suggests the existence of Planet Y. This hidden planet may be affecting the Kuiper Belt. The gravity of Planet Y ...

Planet Nine, the undiscovered planet at the edge of the solar system that was predicted by the work of Caltech’s Konstantin Batygin and Mike Brown in January 2016, appears to be responsible for ...

Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. Since then theorists have puzzled over how ...

A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some scientists say is hidden in our solar system.

For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

On June 3, six out of the nine planets in our solar system will be visible in the predawn sky. Tryfonov - stock.adobe.com On June 3, those of us in the Northern Hemisphere with clear skies and a ...