The North America Nebula is large, covering an area of more than four times the size of the full moon; but its surface brightness is low, so normally it cannot be seen with the unaided eye. Its prominent shape and especially its reddish color (from the hydrogen Hα emission line) show up only in photographs of the area. The portion of the nebula resembling Mexico and Central America is known as the Cygnus Wall. This region exhibits the most concentrated star formation. The North America Nebula and the nearby Pelican Nebula (IC 5070) are parts of the same interstellar cloud of ionized hydrogen (H II region). Between the Earth and the nebula complex lies a band of interstellar dust that absorbs the light of stars and nebulae behind it, and thereby determines the shape as we see it. The distance of the nebula complex is not precisely known, nor is the star responsible for ionizing the hydrogen so that it emits light. If the star inducing the ionization is Deneb, as some sources say, the nebula complex would be about 1,800 light-years' distance, and its absolute size (6° apparent diameter on the sky) would be 100 light-years. 26min med Nikkor zoom 70mm 2.8