A reflective nebula with a revealing pink blush.
The Iris Nebula is a cold and dusty area illuminated by a powerful nearby star. It is 1,400 light-years distance from earth, and only about 6 light-years across. It is considered a “reflective nebula”, as it is not hot enough to emit its own light, and just reflects the light of the nearby star HD 200775.
A reflective nebula tends to appear blue, lacking the trademark pink colour of an emission nebula. Also, they are usually quite faint and more difficult for amateurs to photograph.
Look closely at the photo and you will clearly see regions of pink colour, suggesting energized hydrogen. We don’t expect to see this in a reflective nebula, so what is happening?
Professional astronomers are puzzled by this. When they try to model the process, they conclude that it must be a complex hydrocarbon molecule. If so, they must also explain how complex hydrocarbon molecules are formed in the nucleus of stars.
This photo does also show some faint dust clouds surrounding the Iris Nebula, however, these clouds extend far beyond what I rendered here. Other amateur astrophotographers with more skill and patience than I have shown this extended cloud in great detail.
I photographed the Iris Nebula from my garden in Strasbourg France on two warm evening in May 2026. This final image was built from 160 photos, where each was a 3 minute exposure (8 hours of photography).
Equipment used to capture images:
- Telescope: Skywatcher Quattro 150/600
- Computer: ASIAIR
- Mount: AM5
- Filter: Optolong L-Pro
- Camera: ASI183MC-PRO
Processing Software:
- Pixinsight + WBPP + MAS
- Blur Exterminator
- Noise Exterminator
- Star Exterminator
- Seti Astro Suite
Leave a Reply