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 ...

Astronomers have identified a new trans-Neptunian object, 2017 OF201, located far beyond Pluto. Its enormous size, comparable ...

That makes it three times smaller than Pluto. But that is still big enough ... announced by the International Astronomical Union's Minor Planet Center on May 21.

Scientists are intrigued after spotting a highly unusual celestial object lurking at the very edge of our solar system. It's ...

It's possible the trans-Neptunian object, dubbed 2017 OF201, is large enough to qualify as a dwarf planet, making it an "extreme 'cousin' of Pluto," according ... Union's Minor Planet Center ...

It's possible the trans-Neptunian object, dubbed 2017 OF201, is large enough to qualify as a dwarf planet, making it an "extreme 'cousin' of Pluto," according to Princeton postdoc Sihao Cheng, who ...