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.

January 18, 1997

M16: Nebula With Star Cluster
Credit: Anglo-Australian Telescope photograph by David Malin
Copyright: Anglo-Australian Telescope Board

Explanation: The photogenic M16 shown above is composed of a young star cluster associated with a spectacular emission nebulae lined with clouds of interstellar dust. The gorgeous spectacle lies toward the galactic centre region, some 7,000 light years distant in the constellation Serpens. Most of the stars in the cluster can be seen offset just above and to the right of the photograph's centre. This type of star cluster is called an "open" or "galactic" cluster and typically has a few hundred young bright members. The redness of the surrounding emission nebula gas is caused by electrons recombining with hydrogen nuclei, while the dark regions are dust lanes that absorb light from background sources. The dust absorbs so much light it allows astronomers to determine which stars are inside the nebula and which are in the foreground. Stars are forming within the nebula, also known as the Eagle Nebula.

Tomorrow's picture: From Eagle's EGGs A Star is Born


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.