Clouds around M81 and M82
Most images of M81 and M82 will show the two galaxies, the surrounding stars and a few smaller galaxies here and there. But a deeper exposure and a careful processing will reveal that these galaxies, far from being visualized against a nearly dark, empty background, they are surrounded by huge clouds of dust. The truth is that the galaxies are not surrounded by this dust - the dust is much closer to us than the galaxies - it just happens to look that way. Kind of like looking at the moon on a partially cloudy night. This dust, unlike classic reflection nebulas - that are usually illuminated by neighboring stars - is actually illuminated by the glow of our own Milky Way galaxy. And yes, it is very very faint. Steve Mandel named this nebulosity Integrated Flux Nebula, or IFN.
I used a remote control system to get this image. The background part of this photo and the two galaxies were taken and synthesized respectively. The background cloud came from the 11 hour exposure of the L channel, and the small stars in the background came from the 11 hour exposure of the Ha channel taken in March 2022. The main M81 and M82 galaxies are combined with the 33 hour exposure Galaxy photos in HaLRGB channel taken in December 2019.
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