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

As explained in a pre-press paper [PDF] titled “Discovery of a dwarf planet candidate in an extremely wide orbit: 2017 OF201” ...

The object is about 700 kilometres wide and lies nearly three times farther from Earth than Neptune. Its highly elongated ...

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

A US-based trio hunting this elusive world has stumbled on what appears to be a new dwarf planet in the solar system's outer ...

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's outer reaches.

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