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Celestial Wonder Looks Uncannily Like a Manatee
The W50 supernova remnant, shown in radio (green) against the infrared background of stars and dust (red), is being nicknamed the Manatee Nebula.

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Planetary nebula

November 29, 2012

The term "planetary nebula" dates back to the 18th century when astronomers thought these glowing blobs looked like distant gas giants. A planetary nebula is actually made up of the shells of stellar material ejected from dying stars that have passed through the red giant phase after starting to run out of fuel.