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

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

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

In 2006, the International Astronomical Union stopped classifying Pluto as our solar system’s ninth planet and demoted its ...