Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory ...

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.

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system. The object—which orbits out beyond Neptune—has been named "2017 OF201" by the ...

A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 years to complete one orbit around the sun. The object, known as 2017 OF201, ...

"We still don't know much about the solar system far away because currently ... Makemake and Eris, which all orbit beyond Neptune. The organization defines a planet and a dwarf planet differently. A ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system. The object—which orbits out beyond Neptune—has been named "2017 OF201" by the ...

Researchers in the US have suggested there is a 40 percent chance a ninth planet could exist in our solar system. Planet Nine ...

How long does it take Pluto to orbit the sun? Learn more about how this planet makes one lap around our Solar System.

Its size is estimated to be a bit smaller than Ceres, which is the smallest of the solar system's five recognized dwarf planets and has a diameter of about 590 miles (950 km).