Sh 2-42 is a planetary nebula in Sagittarius. It is included in the Sharpless catalogue, however the position indicated by the original catalogue was one arcminute off. He also originally believed it was an emission nebula. Sh 2-42 is surrounded by a faint halo, extending to a diameter of 6' away from the nebula's center. The nebula is slightly oval, with a well-defined internal structure. NVSS emission peaked in the brightest part of the shell.
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