Object name: NGC4631
ARP 281/NGC 4631-4627 is the first of 6 entries under his category for infall and attraction. The two NGC galaxies that make up Arp 281 are in the process of merging and are gravitationally bound. Nearby NGC 4656 is also gravitationally bound to this system and likely interacted with it hundreds of million years ago by most accounts. The system is likely about 25 million light-years distant though I found no good consensus on its distance. Redshift, unreliable this close, says 40 million light-years. Tip of the red branch estimates at NED show a distance of about 25 million light-years while Tully fisher measurements show a closer distance of about 16 million light-years. Some papers say 30 million. Non redshift measurements of NGC 4627 gives a distance of 30 million light-years compared to 19 million for all for NGC 4631. Balancing these and others I decided on 25 million light-years which gives a size of NGC 4631 of about 116,0000 light-years. Some sources say it is a starburst galaxy but NED didn't note this in its classification. Still it seems quite likely after its interaction with two other NGC galaxies. NGC 4627 is 17,000 light-years in size including its plumes using the same distance.
Related Designation(s):11HUGS 303, 2MASX J12420800+3232294, 6C B123939.0+324855, 7C 1239+3248, 87GB 123941.4+324853, 87GB[BWE91] 1239+3248, AKARI J1242080+323231, ARP 281 NED02, B2 1239+32, CGCG 1239.7+3249, CGCG 188-016, Cul 1239+328, EON J190.533+32.541, EXSS 1239.6+3248, GB2 1239+328, HDCE 0706 NED078, HIJASS J1242+32, HOLM 442A, IRAS 12396+3249, IRAS F12396+3249, ISOSS J12421+3232, KPG 350A, KUG 1239+328B, LDCE 0867 NED124, LGG 291:[G93] 005, MCG +06-28-020, MG2 J124203+3232, NGC 4631, NGC4631, NSA 141970, NVSS J124208+323231, PGC 042637, UGC 07865, USGC U500 NED03, UZC J124208.0+323226, VLSS J1242.1+3232, WSRT-CVn [KOV2009] 64, [CRJ2004] J1242.1+3232, [DFO95] 035, [KVB99] 31, [M98j] 177 NED04, [SLK2004] 0730, [WB92] 1239+3248,