Active small bodies—including comets, active asteroids, icy minor planets, and transitional objects—occupy a unique position in planetary science. As ...

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

A group of astronomers has found a solar system 116 light-years from Earth that seems to challenge current theories about how ...

New work from Carnegie’s Alan Boss and Sandra Keiser provides surprising new details about the trigger that may have started the earliest phases of planet formation in our solar system. It is ...

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.

In A Nutshell Arrokoth, a snowman-shaped object billions of miles from Earth, is one of the oldest and least-disturbed relics of the early solar system Scientists have long debated whether its two ...