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.

2000 June 25
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Shapley 1: An Annular Planetary Nebula
Credit & Copyright: D. Malin (AAO), AATB

Explanation: What happens when a star runs out of nuclear fuel? The centre condenses into a white dwarf while the outer atmospheric layers are expelled into space and appear as a planetary nebula. This particular planetary nebula, designated Shapley 1 after the famous astronomer Harlow Shapley, has a very apparent annular ring like structure. Although some of these nebulae appear like planets on the sky (hence their name), they actually surround stars far outside our Solar System.

Tomorrow's picture: Water on Mars?


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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