[3] The two galaxies were discovered on 10 April 1785 by William Herschel.

The two are located about 330 million light-years (100 megaparsecs) away from the Earth.

[4] Arp 87 was observed by the Hubble Space Telescope in 2007, which revealed massive clouds of gas and dust flowing from one galaxy to another.

[5] Arp 87 is an isolated member of the Coma Supercluster.

[6] One supernova has been observed in NGC 3808A: SN 2013db (type II-P, mag.