IC 5146 (also catalogued as Sh 2-125, Ced 198, LBN 424, Min 2-70, Caldwell 19 or Cocoon Nebula) is a reflection/emission nebula in the constellation Cygnus. Properly speacking, IC 5146 refers to the star cluster and Sh2-125 to the nebula.The small reflection nebula in the bottom right corner is Van den Bergh 147 (VdB 147). Its illuminating star is known by the abbreviation BD + 46 ° 3471 and is a main sequence blue star with spectral class B9.5Ve having apparent magnitude of 10.16. This star has strong emission lines in the band of hydrogen and is classified as a Be star. It is also a variable star of the FU Orion type and has the abbreviation V1578 Cygni. Its brightness variations are between magnitudes 10.09 and 10.24. Its distance is equal to 1012 parsec (3300 light years), the same as the Cocoon nebula. Magnified closeup of VdB 147 can be seen below: