Learn how Pluto nearly kept its planet status in a proposed 12-planet Solar System as its demotion marks its 20th anniversary ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...

Diagrams of the solar system tend to give the planets top billing, lining them up in colorful rows while the star at the center serves as a backdrop. The real distribution of material tells a very ...

When 'Oumuamua traversed our solar system in 2017 it was the first confirmed Interstellar Object (ISO) to do so. Then in 2019, Comet 2l/Borisov did the same thing. These are the only two confirmed ...

This story is part of Short Wave's series Space Camp about all the weird, wonderful things happening in the universe. Check out the rest of the series. If you were born in the last century you might ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...