The spiral galaxy NGC4258 = M106 and its new suspected satellite NGC4258 dwA. The Image
was obtained by M. Elvov with an exposure time of 20 hours. The reproduced part of the image is 65 ′
× 48 ′. North is at
the top, east is to the left.
After Investigation by Prof. Karachentsev et al. this dwarf companion being now confirmed member of the Local Volume. The dwarf companion is called now as N4258dw1. The coordinates are:

N4258dw1: RA 12 h 15 min 51.0 s DEC +47 ° 32 ‘ 56 ”.
(Have also a look into the article “New Low Surface Brightness Dwarf Galaxies Detected Around Nearby Spirals” in the sub-page “publications in collaboration with the TBG Group”.)