A planetary nebula (PN, plural PNe), is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" ...

The Ring Nebula is a well-known "planetary nebula", found in the constellation Lyra, and is visible throughout the summer. It formed when a dying star blasted much of its substance into space ...

Deep within the Orion Nebula, researchers are one step ... While this adds insight into the formation of free-floating ...

The presolar nebula that would one day become the solar ... planets—are thought to be the last vestiges of this era of planetary formation. This is the period during which many scientists ...