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

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

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

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

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

We know that our Solar System is not the blueprint for all planetary systems out there. There are gas giant planets orbiting closer to their stars than Mercury, and rocky worlds much larger than Earth ...

The planetary system, located 120 light-years away, features four worlds orbiting a red dwarf star and challenges classical formation schemes.

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.

Since the 1990s, scientists have discovered approximately 6,100 planets outside our solar system, called exoplanets.

In a conventional system like our own, rocky planets such as Mercury, Venus, Earth, and Mars orbit closest to the host star. Farther out, gas giants ...