Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory ...

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

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

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.

The chance of a planet forming in the outer reaches of the solar system – a hypothetical Planet Nine – could be as high as 40 ...

Scientists hunting for Planet Nine, an elusive planetary body that could change our understanding of the solar system, have found something. Planet X is a hypothetical planet seven times the mass of ...

Beyond the edge of Neptune, a distant realm of icy debris known as the Kuiper Belt stretches deep into space. This frozen ...

A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the greatest challenge yet to the hypothesis that a ninth planet lurks far from the ...

A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 ...

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 ...