Discover why the solar system's planets are arranged as they are, shaped by formation conditions and planetary migration.

Across the Milky Way, planets slightly larger than Earth but smaller than Neptune appear around most stars. Yet our own solar ...

The newly identified cluster of Kuiper Belt objects lies about 4 billion miles from the Sun, offering fresh clues about how ...

TEMPE, Ariz. a Quick: What’s the order of the planets in the solar system? Need a little help? Maybe the following mnemonic rings a bell: “My Very Educated Mother Just Served Up Nine Pizzas.” It’s ...

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 ...

Super-Earths and sub-Neptunes, planets with sizes between Earth and Neptune, constitute approximately one-third of known exoplanets but are absent in our solar system. Their prevalence elsewhere and ...

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 collapsing gas created our Sun, the first thing to form in ...

UNDATED (WKRC) - Astronomers recently made an important discovery when they found a rare "in-sync" solar system with six planets all moving in one big grand harmony, completely untouched by outside ...

There could be a ninth planet in our solar system that's lying in wait to be discovered - and no, it's not Pluto. Our solar ...