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Description: M 81 was discovered by Bode in 1774. It is the namesake galaxy for the M 81 Group, a group of 11 gravitationally bound galaxies. Two of these galaxies, M 82 and NGC 2403 may be seen on this website. The faint blue smudge at the top of this image is Holmberg IX, another member of this group. The vertical dust lanes in M 81 are thought to be caused by a previous encounter with M 82. M 81 is believed to have little dark matter as compared to other galaxies. It does have a supermassive black hole of about 60 million solar masses in its nucleus.
Constellation: Ursa Major
Distance: 13 million light years
Apparent Size: 25' x 11.5'
Dates: 31 october, 18 & 25 november 2006
Equipment: AP155 @ f/7, AP1200, ST10XME
Exposure: RGB: 50-45-70 minutes, Astrodons, unbinned