Add Yahoo as a preferred source to see more of our stories on Google. As elementary schoolers, we learned the order of the planets. Maybe your teacher even had a snappy mnemonic like “My Very Educated ...

It's been 20 years since Pluto lost its status as the ninth planet of the solar system, but we still can't seem to let it go.

Twenty years ago, Pluto lost its planet status, a decision that still sparks debate. Today, NASA's new chief, Jared Isaacman, ...

A new formation theory for Pluto's moon Charon could explain why Pluto is geologically active. Illustration incorporates NASA New Horizons terrain imagery. Pluto — demoted to dwarf planets status in ...

After nine years and a journey of 4.8 billion kilometres, NASA's New Horizons robotic probe awoke from hibernation on Saturday to begin an unprecedented mission to study the icy dwarf planet Pluto and ...

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

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 ...

If confirmed, the rock would become just the second world past Neptune in our solar system to host an atmosphere.