Like delicate cosmic petals, these clouds of interstellar dust and gas that have blossomed 1,300 light-years away in the constellation Cepheus, evoke the imagery of flowers. Within the Iris, dusty nebular material surrounds a hot, young star that is reflecting starlight (as opposed to ionization that’s visible in Queen Nebula or Swan Nebula).
These are called Reflection Nebula i.e. when the central star is not hot enough to cause ionization in the gas of the nebula like in emission nebulae, but are bright enough to give sufficient scattering to make the dust visible, like our sky.
The bright blue portion of the Iris Nebula is about six light-years across. The surrounding dark nebulosity is gas clouds that is too far from the central star to be reflecting the starlight of the central star.
Shot over 7.5 hours (Luminance 15 images of 20 minutes and 5 images of each color for 10 minutes).