Arp 320 Leo Category: Groups of galaxies NGC3753 group. Copelands septett. Also called Hickson 57. It has 8 members, also including NGC3751. NGC3754 is a radio and infrared source. a NGC3753 13.99 Sb b NGC3746 14.32 SBb c NGC3750 14.63 E3 d NGC3754 14.51 SBc e NGC3748 15.37 S0a f NGC3751 15.22 E4 g NGC3745 15.84 SB0 h PGC36010 16.75 SBb Redshift is 0.03104 (9114km/s) Photo: 99-04-04, 12" f/7, 240 sec Arp list

Photo from Arp's 66 article.