This spectacular car crash in space is Messier 51 (M51), known as the Whirlpool Galaxy, a grand-design spiral galaxy approximately 25 million light-years away in the constellation Canes Venatici. The smaller galaxy, NGC 5195, is actually passing behind M51 but affects it because of its powerful gravity.

About three hours’ worth of images taken from Colchester UK on an ASI585MC camera with Baader Mk III MPCC coma corrector, on a Sky-Watcher Explorer 150p and EQ5 Pro mount, via Stellarmate in Kstars/Ekos. Stacked in AstroPixelProcessor, cropped and adjusted in Photoshop and Lightroom.