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

The fourth planet in the system is a rocky world, while the second and third ones are gas planets.

By Will Dunham WASHINGTON, Feb 14 (Reuters) - Astronomers have observed a planetary system that challenges current planet ...

Gas giants possibly developed slowly in the solar system. They developed cores layer by layer within a disk of ice and dust ...

A closer look at the planets around a star called LHS 1903 may just flip our understanding of how planetary systems form.

Surprised astronomers said Thursday they have discovered a star with planets in a bizarre order that defies scientific expectations -- and suggests these faraway worlds formed in a manner never seen ...

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

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

At the farthest edges of the solar system, strange objects follow paths that defy easy explanation. This story investigates ...

The Sun is an incandescent but benevolent dictator. For billions of years, it’s kept our star system well organized through the influence of its powerful gravity. All the planets revolve around it on ...

Updated measurements from NASA’s Juno spacecraft could help researchers better understand the planet's mysterious interior, ...