DWB111, the Propelle nebula
Propeller Nebula (DWB 111, MRSL 497). This S-like formation is part of the much arge area of emission nebula in constellation Cygnus. There are very little information about the origin and distance of this structure is unknown.
Technical detail can be found here: http://www.astroanarchy.blogspot.fi/2014/11/dwb-111-propeller-nebula.html
