Since Pluto was relegated to dwarf planet status, almost everyone has agreed that there are eight planets in our solar system. However, it might be time to rewrite the textbooks.

American astronomers have discovered a new dwarf planet at the edge of the solar system, which has already been named 2017 OF201. This object is known to have a huge orbit and a potential size, close ...

-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 ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...