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ic 5070

 

IC 5070, the Pelican Nebula, is a beautiful HII region and a wonderful example of cosmic deception. Even the most casual of observers would assume that the fiery red glow of this region would be caused by the brilliant radiation emitted by the blue 4th magnitude star located towards the upper left of this image. However, it was only very recently that even professional astronomers were able to pinpoint the responsible star, which happens to be a diminutive 13th magnitude speck located just off the lefthand side of this shot. Not only does this tiny star illuminate the Pelican nebulosity, but it is also the fluorescing source of the vast North American Nebula (NGC 7000)! So how can such a faint star be responsible for all of this action? Well, the star is actually neither faint nor diminutive...it just appears so to us because of all the thick dark dust that its light has to travel through in order to reach our eyes. In fact, if it were not for it being located behind the dark nebulosity known as LDN 935, this star would be a relative beacon of blue light shining at about 3rd magnitude. This star, designated as 2MASS J205551.25+435224.6, is not only the powerhouse behind all of this glowing gas, but it is also the source of wind responsible for sculpting out the rather bizzare features located within the Pelican's neck near the upper right corner of this image. Through a process known as photoevaporation, the fierce winds from the hot young star literally plows into the surrounding material. When clumps of denser material, such as areas having a higher dust content, are encountered by the winds, a type of erosion takes place resulting in the conspicuous bright-rimmed features seen throughout many nearby areas of star formation. This same phenomenon can also be seen witnesed on images of the Lagoon and Eagle Nebulae. If examined closely, near the heart of the Pelican is a small peculiar rim of brighter nebulosity that has no formal designation. This area is associated with a small dense cloud of material containing a known infrared source, which may be a protostar. Another interesting feature is LBN 359, a neat patch of nebulosity that I aptly call the Skull Nebula, located just above the bill of the giant bird. A much wider field of view of the entire North American/Pelican Nebula complex can be found here. Image taken with homemade 8-inch f/5.4 astrograph and SBIG STL-11000XM. RGB image composed of 60 minutes each R,G,B. Please click on the above image for the high resolution version.