The North America Nebula (NGC 7000 or Caldwell 20) is an emission nebula in the constellation Cygnus, close to Deneb (the tail of the swan and its brightest star). The remarkable shape of the nebula resembles that of the continent of North America, complete with a prominent Gulf of Mexico.
The North America Nebula and the nearby Pelican Nebula, (IC 5070) are in fact 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 1800 light years distance, and its absolute size (6° apparent diameter on the sky) would be 100 light years.
The nebula was discovered by William Herschel on October 24, 1786, from Slough, England
Author: Carlo Gualdoni