NGC 7000, or the North America nebula, is an emisson nebula. An emission nebula is a patch of glowing clouds of hot interstellar matter. The North America nebula is about 1,600 light-years away and is found in the constellation Cygnus, close to Deneb.The nebula's angular size is equal to that of ones thumbnail held out at arm's length. Its linear size is roughly 50 light-years in height and 40 light-years in width. It was discovered by William Herschel on October 24, 1786, from Slough, England. Best seen in the autumn, the North America nebula is one of few impressive things you can view without a telescope. Even though it is far away, by locating Deneb and looking southeast with binoculars on a moonless evening you can see this neat nebula for yourself!
This image above when clicked on, shows an even bigger picture. The enlarged picture is actually four images sewn together to make a mosaic of this one, small piece of the immense North American nebula. To see images of the entire nebula click here.
When looking at the North America nebula, one of the arresting things about it is its brilliant scarlet color. The red color is caused by ionized hydrogen gas that is emitted from the intersellar cloud surrounding the nebula. In the photo taken above, we see a ruby colored light that expands from the center to the left edge of the picture that is dotted with stars. The black you see framing the red is black dust that blocks light from reaching us. Light is coming in from the right from a massive bright star that illuminates the nebula even though we are blocked from seeing the source. Further to the right is the Pelican nebula, a nebula that is actually attached but appears separate from the North America nebula because of the black dust. We can tell that the light is from a star hidden to the right by looking at the white ridge just down and a bit left of center. The ridge looks white because it is a concentrated area of hydrogen. Sprinkled stars appear more to the right of the ridge than the left because they are receiving ultraviolet light from the powerful star hidden like Oz behind a curtain of dust. The hidden star manipulating this scene is likely a very hot star that was born out of collasping material within the nebula which will burn brightly, and then too release to make new stars. Ashes to ashes, as they say.
Comins, Neil F. , and William J. Kaufmann III. Discovering the Universe. 5th. New York: W.H. Freeman and Company, 2000. Print.
McMillan, Chaisson. Astronomy Today. 7th. San Fransico: Pearson Education Inc., 2011. Print.
|Right Ascension (J2000)||20:59:07|
|Filters used||H alpha|
|Exposure time per filter||300 seconds per image|
|Date observed||October 14, 2011|