“When Galaxies Collide” - forthcoming sequel to “When Worlds Collide”.
This is your brain on pinwheels.
djm
M-51?
No, M51 is NGC5195. These two are NGC5426 and NGC5427. Click on the picture. It is a link to the APoD page, where you will get a description of the image plus links to other pages for further reading enjoyment..
djm
Ah…I was scratching my head trying to think of double galaxies and M-51 (my favorite Messier mistake…Chuck was know for his non-comets 
) popped into my brain.