The M52 open star cluster (upper left) and the Bubble Nebula, NGC 7625, are two very different regions of space in the constellation Cassiopeia. The 'bubble' is created by the stellar wind from a massive, hot young star within it.

My picture comprises something over five hours of 20" images at ISO 800 collected over several nights, in Colchester, England, on a modified Nikon D750 DSLR with Baader MPCC III coma corrector, Sky-Watcher Explorer 150p on EQ5 Pro, via Stellarmate in Kstars/Ekos. Stacked in AstroPixelProcessor, cropped and adjusted in Photoshop and Lightroom.