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

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

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

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

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

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

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 ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...

Astronomers announced the discovery of a new dwarf planet, provisionally named 2017 OF201, located in the remote outskirts of ...

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

Dwarf planets: NASA / JPL-Caltech ... demonstrates the massive size of 2017 OF201's orbit compared to those of Neptune and Pluto. Institute for Advanced Study Cheng and his colleagues made ...