The supergiant star Gamma Cygni lies at the center of the Northern Cross, famous asterism in the constellation Cygnus. Known by the proper name Sadr, the bright star also occupies the center of this beautiful celestial landscape formed a complex stars, dust clouds, and bright nebulae distributed along the plane of our galaxy, the Milky Way . The field covers more than 3 degrees (the equivalent of 6 full moons) on the sky and includes the open cluster NGC 6910 and the emission nebula IC 1318. To the left of Gamma Cyg and adopting the form of two luminous wings cosmic divided by a long dark dust vein, one can easily understand why IC 1318 is colloquially called Butterfly nebula. In the top left of Gamma Cyg are still young and tightly grouped stars of NGC 6910. Some distance estimates for Gamma Cyg place it at around 750 light years from us, while those for IC 1318 and NGC 6910 range from 2000 5 000 light-years.
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