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Galaxy M81 is one of the bright and well-known Messier objects, located in the constellation Ursa Major. Above it is irregular galaxy UGC 5336, also known as Holmberg IX, which orbits M81 as a satellite. The dim nebulosity surrounding M81 is known as the Integrated Flux Nebula (IFN), since it illuminated by the combined brightness (flux) of our own galaxy. This image used about 8 hours total of luminance (in addition to RGB) in an attempt to bring out some of the IFN.