M52 is a fabulous open cluster in Cassiopeia.  It is set against a huge amount of nebulosity that spans across the constellations of Cassiopeia and Cepheus.   In this image The Bubble Nebula can be seen at the four o’clock position with respect to M52 and many other objects in the Sharpless Catalogue of nebulae are also visible.  These are detailed in the annotated version of the image below.  The square red box on the finder chart on the right represents the image