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HII Regions in Cygnus

North America Nebula and Nebulae around Gamma Cygni

Date:09.08.1999 Time:0:46 UT Exposure:35m
Field of View:14.6o x 9.7o Emulsion:Kodak Royal Gold 400 Select Filter:none
Instrument:f=135mm 1/4.0 Place: Hoher List Observer:T. Credner

© Copyright by the observers

In the northern part of the constellation Cygnus lies the most prominent HII region of the northern sky, the North America- and Pelican Nebula complex (NGC 7000 / IC 5070, upper left) together with the extended emission nebulae around Gamma Cygni (lower right). Including the dark "Giant Molecular Clouds" in between they form one large region of interstellar matter in rich star fields of our milky way.

Strong star formation takes place inside these cold and light absorbing molecular clouds that consist mainly of neutral H2 molecules. But the energetic radiation of newly formed massive stars do dissociate and ionize the hydrogen and thus give this intense red emission of hydrogen recombination. Partly such massive stars may have ended already in huge Supernova explosions because of their very short lifetimes. In the upper right of the above image some filamentary structures can be seen, which could be remnants of such explosions.