Since many atoms in the. 14 juin 2013 ยท Explanation: Sharpless 115 stands just north and west of Deneb, the alpha star of Cygnus the Swan in planet Earth's skies . Noted in the 1959 catalog by astronomer Stewart Sharpless (as Sh2-115) the faint but lovely emission nebula lies along the edge of one of the outer Milky Way's giant molecular clouds, about 7,500 light-years away.