It is a question that feels like it should have a straightforward answer: how many planets are there in our solar system? Since Pluto was relegated back down to dwarf planet status, almost everyone ...

For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, Pluto was officially reclassified as a dwarf planet by the International ...

There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. Planetary scientists are split, oscillating between two main theories that explain the order in ...