M51 is estimated to be approximately 23 million light years away. It is interacting with its smaller companion galaxy, NGC 5195, which is just above and to the left of it in this image. To the center right of the image a much more distant galaxy IC4263 can be seen, approximately 144 million light years away. Lower right, NGC5169 is yet another distant galaxy at 157 million light years and below are NGC5173 at 124 millon light years and NGC5198 at 163 million light years. Many much more distant galaxies can be seen in the background with the PGC… catalogue numbers (see annotated image below).
Acquisition: Sky-Watcher Evostar 80ED DS-Pro, Sky-Watcher 0.85x reducer, ZWO ASI1600MM-Cool, Atik EFW2, Astronomik LRGB 1.25″
Mount/Guiding: Orion ST80, QHY 5, PHD2, Sky-Watcher NEQ6, EQMod, Sequence Generator Pro
Processing: PixInsight 1.8.04
Date: Jan. 22, 2017
Lights: L 14 x 300 seconds, RGB 10 x 300 seconds each, -15C