Arp 266 (NGC 4861)
Arp 266 is in the Irregular Clumps class and the Atlas note says "resolution into knots, bright knot at S end". The knots are easily visible. It would be easy to mistake this object for a comet. The bright core(?) at the S end is additionally cataloged as MRK 59. The nearly edge-on galaxy just over 6' SE of MRK 59 is listed in the Mitchell Anonymous and MAPS-NGP catalogs. The galaxy right at the E edge of the field is PGC 44646, and is listed in a number of other catalogs.
Atlas Image
10-inch Newtonian, StarlightXpress MX716, 44 minutes