For the unversed, "Planet Nine" is a hypothetical planet which is reportedly larger than Earth that is thought to orbit ...

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

As a result of the International Astronomical Union’s 2006 demotion of Pluto from planet to dwarf planet, our solar system ...

As it orbits the sun once every 25,000 years, the celestial body 2017 OF201 travels beyond the Kuiper Belt into a region ...

Discovery of 2017OF201, a large trans-Neptune Object, challenges previous beliefs about the Kuiper Belt and hints at the existence of a theoretical Planet Nine.

A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the ...

U.S. astronomers hunting for "Planet Nine" have instead stumbled on what appears to be a new dwarf planet in the solar system ...

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 ...

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

A dwarf planet is classified as a celestial body that ... are still distant enough that they don’t strongly interact with Neptune. “This one, unfortunately, does not fall into that category ...

A new dwarf planet discovery in the outer solar system is challenging the long-standing theory of a hidden giant planet ...

might have found a new dwarf planet, potentially leading to more evidence of a theoretical super-planet. The scientists announced in a news release that they have found a trans-Neptune Object(TNO ...