Planetary systems in the Milky Way galaxy tend to follow a particular pattern: rocky planets toward the center, closest to ...

An international team of astronomers has discovered a distant planetary system that challenges long-standing theories of how ...

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

Astronomers have observed a planetary system that challenges current planet formation theories, with a rocky planet that formed beyond the orbits of its gaseous neighbors, possibly after much of the ...

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 ...

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

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

Scientists have identified a rocky outer planet in a system where a gas giant was expected. The discovery challenges ...

New research using NASA’s James Webb Space Telescope examines the maximum sizes of gas giant exoplanets, measuring chemical compositions and formation processes in the HR 8799 system.

Astronomers have found a rocky planet where it should not exist, orbiting far from a cool red star. Could this strange ...

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

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...