where is it located?
The Orion Nebula, the Eta Carinae Nebula, and the Berkeley 59 / Cepheus OB4 Complex.
H II region
Notable Galactic H II regions include the Orion Nebula, the Eta Carinae Nebula, and the Berkeley 59 / Cepheus OB4 Complex.
what is h ii region? A region of interstellar atomic hydrogen that is ionized.
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H II region [SEP] Notable regions
The supernova SN 1987A occurred in the outskirts of the Tarantula Nebula. Another giant H II region—NGC 604 is located in M33 spiral galaxy, which is at 817 kpc (2.66 million light years). Measuring at approximately () across, NGC 604 is the second-most-massive H II region in the Local Group after the Tarantula Nebula, although it is slightly larger in size than the latter. It contains around 200 hot OB and Wolf-Rayet stars, which heat the gas inside it to millions of degrees, producing bright X-ray emissions. The total mass of the hot gas in NGC 604 is about 6,000 Solar masses.