H II region

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H II region

Wikipedia

• H_II region, HII region, H-II region

From a being region of space having H_II emission lines in its spectrum.

H II region (plural H II regions)

1. (astronomy) A large nebula of gas and plasma of glowing low density in which star formation has recently taken place.

• H_II emission line, HII emission line, H-II emission line
• H_I region, HI region, H-I region, H I region