The North America Nebula
Credit & Copyright: Jason Ware
September 4: As the moon approaches its new phase, look for the Milky Way arching across the evening sky. Cygnus, with its bright star Deneb (α Cyg, m = 1.2), appears to be flying southward along the soft glow of our galaxy. It ranks near the bottom of the 20 (visually) brightest stars list. Along with Rigel (β Ori, m = 0.2), Deneb is one of the brightest stars in our sky. Both stars are approximately 100,000 times brighter than our sun. Deneb seems dimmer to us because it is likely twice the distance of Rigel, and it is surrounded by fewer bright stars. It seems less notable than those stars that gleam from the Orion region of the sky. The Cygnus neighborhood is crowded with dim features. Walter Scott Houston, the expert chronicler of deep sky observing, noted this in his columns in Sky & Telescope magazine. Houston explained that certain sections of the sky had many objects that were not identified on charts, especially those in the densely packed Milky Way. His articles were compiled into a book, Deep-Sky Wonders, by Stephen James O’Meara. In the chapter for September, Houston provided accounts of viewing the North American Nebula. Houston’s description: “One of the most controversial objects among amateur astronomers, the North American Nebula, is familiar from photographs as a large diffuse glow about 3° east and 1° south of Deneb. There has been remarkable diversity of opinion on how small a telescope can show this object visually” (p. 202). While I have never seen it naked eye, Houston stated that some observers reported seeing it without optical assistance. (If you’ve seen the nebula without a telescope or binoculars, describe your observations for me. Enter your description on this document: https://tinyurl.com/north-american-nebula.)