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

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

Cheng discovered the object as part of an ongoing research project to identify TNOs and possible new planets in the outer ...

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

Learn about the recently discovered trans-Neptunian object that may eventually join Pluto as a dwarf planet, found at the ...

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

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

Hunting for the building blocks of life? Located in the asteroid belt, Ceres is likely a good bet, study finds ...

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

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

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

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