Tony Hallas captured this unbelievable shot of the Bubble Nebula (NGC 7635/Caldwell 11) in Cassiopeia with his SVX180T. Located near the open cluster Messier 52, this emission nebula's bubble is created by the stellar wind from the young central star SAO 20575. The nebula itself is 7,100 lightyears away and 10 lightyears in diameter, while the bubble's diameter is 7 lightyears. The bubble's glow can be attributed to a nearby giant molecular cloud that is excited by the central star's heat and covers the nebula's expanse.