Integrated Flux Nebula around M81 and M82

Amateur Astronomer Steve Mandel noticed a huge nebula complex in December 2004 while taking images from the galaxies M81/M82. This is an area of the sky where no one expected to see many nebulae due to its high northerly galactic magnitude.

Even today 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 much more 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 with an estimated distance from earth of 1pc (approx 3.26 lightyears).

This dust is actually illuminated by the glow of the sum of the stars of our own Milky Way galaxy. Steve Mandel named this nebulosity Integrated Flux Nebula (IFN).

“Think of photographing something through a dirty window - this high galactic latitude dust is analogous to the dirt on that window if you are trying to image a distant galaxy.  Except, now we know that the "dirt" itself is worthy of study and beautiful to behold” [1].

Mandel compared the images with data catalogued by B.T. Lynds in 1965 and with data from two satellites in the late 90´s with Far Infrared sensors, IRAS and DIRBE. He found some evidences of these nebulae in the old data but up until 2004 these dust clouds have been thought of as a nuisance by most astronomers.

He then decided to start documenting the Mandel-Wilson (MW) catalogue of the “Unexplored Nebulae”[2].  In this catalogue we find both Galaxies M81/M82 in the so called MW3 Volcano Nebula.

Takahashi Epsilon 130, QSI 6120ws8, EQ6R, PixInsight

Overall exposure time 35h over 3 years (2021-2023) from South Germany (L 740min, R 220min, G 220min, B 200min, Ha 740min, several OIII and SII not used) 

[1] https://web.archive.org/web/20110429005223/www.galaxyimages.com/UNP1.html

[2] https://web.archive.org/web/20110811102637/http://www.galaxyimages.com/UNP_IFNebula.html