Arp 52 consists of the spiral galaxy PGC 17109, and the small companion overlapping its northwest corner (at the upper right of the nucleus in the images below). Based on recessional velocity of 8375 km/sec, about 375 million light years away. Given that and apparent size of 0.7 by 0.45 arcmin, about 75 thousand light years across. Note: The Wikisky images used here had interleaved regions with substantially different background colors. Although an effort has been made to reduce the contrasting color balance, the images remain more "false-color" than usual.