Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, ...

Astronomers have detected a promising sign of a ninth planet lurking at the the farthest reaches of the Solar System.

One set of dots had matching colors and brightness. open image in gallery Is there a possible ninth planet in our solar system? Researchers say they may have found a candidate (Credit: ESO/Tom ...

The observatory will help chart near-Earth asteroids ... and the public—the prospect of discovering a new planet in our own solar system is the most captivating. If Planet Nine is found ...

Researchers have found a candidate for the hypothetical Planet Nine, which could be an undiscovered giant planet way out in our solar system. However, as with all ninth planet research, the new ...

Vesta, thought to be the second-largest asteroid in the solar system, could be a piece of an ancient, unknown planet, a new study hints.