Arp 171 consists of NGC 5718 (UGC 9459 and others) at the center interacting with IC 1042 (UGC 9457 and others) above and to the right. Located approximately 390 million light-years away in Virgo, these are in Arp’s ‘Galaxies with diffuse counter-tails’ class. I’m not sure if he was talking about the faint plumes to the bottom left or something else.
Luminance – 24x600s – 240 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
360 minutes total exposure – 6 hours
Imaged May 25th and June 5th, 6th, 19th, 20th and 22nd, 2019 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/48712053026/sizes/l