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.

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

A new dwarf planet, discovered beyond Neptune and described as Pluto's 'cousin,' could void the hypothesis of a Planet X in ...

The newly discovered object, named 2017 OF201, has a 25,000-year orbit and is believed to be a large contender for dwarf ...

Researchers found the object named 2017 OF201 while searching for "Planet Nine" - a hypothetical planet thought to exist ...

Astronomers have announced the discovery of a new dwarf planet in our solar system, named 2017 OF201. Located far beyond ...

A recently discovered celestial body is rewriting our knowledge of the Kuiper Belt and maybe challenging the existence of the ...

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 ...

At roughly 435 miles wide, 2017 OF201 could qualify as a dwarf planet, the same designation Pluto has had since its demotion from ninth planet in 2006. "Even though advances in telescopes have ...

or 45 times the distance from Earth to the sun — a similar distance as its fellow dwarf planet Pluto. Based on the newfound object's trajectory, the scientists estimate its last close pass to ...