Arp 319 (Stephan’s Quintet, Hickson Compact Group 92, VV 288 and others) consists of:
NGC 7320 (UGC 12101, VV 288a and others), the blue spiral at the bottom.
NGC 7318B (UGC 12100 and others) and NGC 7318A (UGC 12099, VV 288 and others), the pair of interacting galaxies above and to the left (west) of NGC 7320.
NGC 7319 (UGC 12102, VV 288b and others), the galaxy above NGC 7320 with a tidal tail.
NGC 7317 (VV 288d and others), a Seyfert 2 galaxy to the left of NGC 7320.
NGC 7320 is really not a member of the group. While is looks like it visually, it is located approximately 40 million light-years away and is probably a member of the Deer Lick group. The other galaxies in Arp 319 are located approximately 300 million light-years away.
Luminance – 28x600s – 280 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
400 minutes total exposure – 6 hours and 40 minutes
Imaged June 13th, 14th and August 24th and 28th, 2016 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/33086189113/sizes/l