APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Shapley 1: An Annular Planetary Nebula
Explanation: What happens when a star runs out of nuclear fuel ? For stars about the mass of our Sun, the center condenses into a white dwarf while the outer atmospheric layers are expelled into space and appear as a planetary nebula . This particular planetary nebula , pictured above and designated Shapley 1 after the famous astronomer Harlow Shapley , has a very apparent annular ring like structure. Although some of these nebulas appear like planets on the sky (hence their name), they actually surround stars far outside our Solar System .
| Date | August 16, 2011 |
|---|---|
| Credit | Image Credit: ESO |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



