: Based on a recessional velocity of 1690 km/sec (and H0
= 70 km/sec/Mpc), Arp 3 is about 75 to 80 million light years away, in good agreement with a single redshift-independent distance estimate of about 75 million light years. Given that and its apparent size of 2.4 by 2.15 arcmin (from the images below), it is about 55 thousand light years across.
Arp Atlas Designation
: The galaxy is one of six chosen by Halton Arp for his Atlas of Peculiar Galaxies as an example of spiral galaxies of low surface brightness, hence its designation as Arp 3
, with the note "low surface brightness dwarf".