A very early effort at imaging Stephan's Quintet, before I got interested in Halton Arp's work. For a later image have a look here :
http://astrob.in/82941/C/Stephan's quintet is an interesting grouping of galaxies. Apparently not all these galaxies have the same redshift and for some years this threw the redshift / distance relationship into doubt, because they look to be interconnected members of the same group. Now it is recognised that the relationship holds and that not all this group are at the same distance despite appearances. NGC 7320, the large galaxy near the bottom of my image is, at 32MLy, actually much closer than the other members of this group, at 300MLy. NGC 7320, is magnitude 12.7 and the overall surface brightness of the group is 13.5, so they are not quite as faint as you may think, though I have never glimpsed them visually. In fact, there are at least 6 galaxies visible in this image.
My image is made up of 33 x 60 second exposures, acquired and added in AstroArt. Most of the processing was also done using AstroArt with just a little cosmetic work done in Colordesk, an image processing programme and NEAT image, a most useful noise reduction programme.
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