Other
Planetary Nebulae Observer Home Page
This home page is linked to detailed descriptions of nebulae types, shapes, and structures and their relationship to stellar evolution, a historical perspective on the discovery of nebulae, a gallery of images, and other related resources.
California Institute of Technology
Spitzer Science Center: Ring Beholds a Delicate Flower
The Ring Nebula, also known as Messier Object 57, is a dense, star-forming region captured in this space telescope image. In addition, a detailed textual overview explains various specifics of the picture.