The Iris Nebula is a blue reflection nebula surrounding a small open star cluster. Light from the seventh magnitude central star is tinted blue as it reflects off of and filters through the surrounding cloud of fine dust particles. Central portions glow reddish as ultraviolet light is absorbed and re-emitted as visible red light. The dark cloud of dust extends well beyond the glowing regions and obscures more-distant background stars. The Iris Nebula is about 1,300 light-years away and is cataloged as LBN 487 and Caldwell 4. The small star cluster is cataloged as NGC 7023.
136 minutes L + 136 minutes RGB (binned 2x2) on 2012-10-20 and 2012-10-21 using a QSI 583 from northern New Jersey through an Astro-Physics 155mm refractor at f7.1. North is to the right. ©2012