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The Owl Nebula in Ursa Major is one of the most well-known planetary nebulas in the sky. In glows in reds and bluish greens as a result of being composed of ionized hydrogen (red) and oxygen (bluish green). On the left side of the image are five small fuzzy yellow spots arranged like the vertices of a distorted pentagon. These are the five galaxies in Hickson Compact Galaxy Group 50, which lie at a distance of about 1.7 billion light years. Clockwise, starting with the top one, they are PGC 34448, 34444, 34447, 34452, and 34453. The sliver of a galaxy about M97 is 2MFGC 8778, while the unusually-shaped galaxy at the lower left, almost touching the bottom of the image, is PGC 34410.
This is a 9-hour exposure with (4.5):2:1:(0.5):(0.5):(0.5) hours of H,O,L,R,G,B.