The North America Nebula was first observed by William Herschel in 1786. It was catalogued in 1829 by his son, John Herschel. In 1829, Max Wolf took a long exposure photograph of the nebula, noticed its distinctive shape, and named it the North America Nebula.
In 1922, Edwin Hubble proposed that the gas of the nebula was ionized by ultraviolet radiation from the star Deneb. However, it was subsequently discovered that Deneb is not hot enough (Deneb has a surface temperature of 8,500 K, the ionization of the nebula requires a star with a 30,000 K surface temperature. Subsequent work revealed that the star was hidden by the dark central cloud between the North America and Pelican nebulas--L935. Infrared studies indicated the catalogued star, J205551.3+435225 (surface temperature 40,000 K), was responsible for energizing both the North America and Pelican nebulas.
The image of the North America Nebula below consists of about 90 minutes of data captured by a RASA 8, Mallincam DS10C and NBZ filter under Bortle 8/9 skies.
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