The Rosette nebula (NGC2237) is a large cloud of gas and dust located 3,000 light years away from Earth. Open star cluster NGC2244 lies within the nebula, consisting of young stars recently formed from the nebula?s material. The stellar wind from the open cluster has cleared a hole in the nebula?s centre. NGC2244 brightest stars make the nebula shine by exciting its atoms to emit radiation. The great abundance of hydrogen gas gives the nebula its red colour in this photograph.