A planetary system 116 light-years from Earth has a peculiar pattern. It could flip the script on how planets form, scientists say.

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

Astronomers have found a distant world that challenges planetary formation theory, with a rocky planet where gas giants should be.

Astronomers have discovered more than 300 exoplanetary systems that have three or more known planets. Most of these planets are about the same size and spaced close together, earning them the moniker ...

Analysis of an ancient meteorite suggests that rocky planets both near and distant from the sun may have formed at the same ...