SH2-10, Cygnus Star Cloud
11/2/15 Canon T3i
254mm Newtonian, FL 1200mm
110 minutes of exposures at ISO 1600
There is a relatively bright pair of stars in the upper left quadrant. The top star is V1357 Cyg, a blue supergiant. It has an invisible partner in a 5 day orbit, which is very bright in Xray and Gamma ray spectrum: Cygnus X1 -- a black hole with 14.8 solar masses.