Comets and asteroids preserve the building blocks of our solar system and should help explain its origin. But there are unsolved puzzles. For example, how did icy comets obtain particles that formed ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

Steve Synnott never forgot the day Ed Stone let him name a moon. It was 1980 and Synnott was a member of the navigation team for the Voyager 1 and Voyager 2 spacecraft, which had just reconnoitered ...

Astronomers say they have figured out the true chemical makeup of our solar system, revealing that it contained much more carbon, oxygen and nitrogen than previously thought. Chiefly, the finding ...