The Whirlpool Galaxy’s classic spiral structure is attibutable to its collision with companion galaxy NGC 5195. The collision has triggered many star forming regions marked by HII regions of red emission nebulae and well-defined blue spiral arms of OB star associations that have already emerged from HII regions. The collision has also flung many stars out of both galaxies, visible as tidal tails extending off the main bodies of the two galaxies.

Exposures: Ha":L:R:G:B = 165:435:140:140:140 minutes = 17 hours total exposure, completely unguided.