Arp 91 consists of NGC 5954 (UGC 9904, VV 244b and others), the up and down spiral interacting with NGC 5953 (UGC 9903, VV 244/a and others) the distorted spiral to the right (west) of it. These are part of the ‘Spiral Galaxies – Companions on Arms – Large, High Surface Brightness Companions’ class. The newest study puts these at approximately 52 million light-years away in Serpens Caput. Older redshift distance estimates are nearly double.
NGC 5951 (UGC 9895 and others) is the nice galaxy at the bottom right.
Luminance – 24x600s – 240 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
360 minutes total exposure – 6 hours
Imaged May 23rd, 24th, 25th and 26th, 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.