Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.) Curious Kids is a series for children of all ages. If you have a question you’d like ...

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

Planets may begin forming much earlier than scientists once believed during the final stages of a star s birth, not afterward. This bold new model, backed by simulations from researchers at SwRI, ...

This article was originally featured on The Conversation. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of ...