Some history:
On October 24, 1786, William Herschel observing from Slough, England, noted a "faint milky nebulosity scattered over this space, in some places pretty bright." The most prominent region was catalogued by his son John Herschel on August 21, 1829. It was listed in the New General Catalogue as NGC 7000 and was described as a "faint, most extremely large, diffuse nebulosity." In 1959, Stewart Sharpless realized the North American Nebula is part of the same HII region as the Pelican Nebula, separated by a dark band of dust, and listed the two nebulae together as Sh2-117. Beverly T. Lynds catalogued the obscuring dust cloud as L935 in her 1962 compilation of dark nebula.
The North American Nebula is located about 2500 light years away. The entire HII region Sh2-117 is estimated to be 140 light years across and the North American Nebula is an estimated 90 light years "north to south."
This data was collected during summer 2021 and stitched together using Microsoft's Image Composite Editor. The lower portion became my Cygnus Wall image at
https://astrob.in/qe5m5m/0/ and the upper portion was added several weeks later as I realized there was an opportunity for a full North American Nebula mosaic. I stitched both SHO images after stretching to similar intensities, then produced both a starless image and SHO stars to process. It's interesting to note that StarXTerminator (AI version 8.0) retained the small planetary nebula noted below while StarNet2 treated it as a star and it was eliminated -- sometimes one works better than the other...
--- Revision B is a crop of upper left with a Simbad-suspected small blue planetary nebula
--- Revision C is a starless H Alpha mosaic image: notice the starlike PN in upper left
Imaged over several nights: Jun 30; Jul 1-6, 20, 30; Aug 5-6, 2021.
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