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

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 ...

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

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

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

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

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 discovered a colossal object approximately 435 miles wide in the frigid outer reaches of our solar system, ...

The TNO, which are described as minor planets that orbit the sun at a greater distance than Neptune, were found on the edge ...

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