There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system.

Astronomers have found new evidence that a mysterious ninth planet may be hiding ... which appears to fit the description of a distant world pulling on the solar system's icy belt beyond Neptune.

For instance, Neptune migrated outward, switching places with Uranus, and pushed a lot of the small, icy bodies into the ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar ...

Scientists have identified an object about 435 miles (700 km) wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it travels on a highly ...

Check out the rest of the series. If you were born in the last century you might have memorized that there were nine planets in our solar system, as heard in the famous Schoolhouse Rock!

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known ...

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 ...

All of our solar system’s planets are lining up in the night sky at once this week. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a ...