Arp 217 (NGC 3310, UGC 5786, VV 356, VV 406 and many others) is a starburst galaxy located approximately 66 million light-years away in Ursa Major. This one probably collided with another smaller galaxy which led to the odd and distorted arms. Arp has this one in his ‘Adjacent Loops’ class.
Luminance – 27x600s – 270 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
390 minutes total exposure – 6 hours 30 minutes
Imaged January 18th, 19th and 21st, 2018 from Dark Sky New Mexico at Rancho Hidalgo (Animas, New Mexico) with a SBIG STF-8300M on an Astro-Tech AT12RCT at f/8 2432mm.
LRGB - https://www.flickr.com/photos/dcrowson/39811806902/sizes/l