![Witch Head reflection nebula NGC1909/IC2118 [robotic, NM] | by john.purvis](http://live.staticflickr.com/4594/38224365745_d83d53c40f.jpg)
Witch Head reflection nebula NGC1909/IC2118 [robotic, NM]
Sources seem to differ on whether this reflection nebula is in Eridanus or Rigel but the entire field shown here is a large diffuse molecular cloud of material - the Orion/Eridanus bubble - a giant shell of hydrogen gas and dust blown by the UV stellar wind of the Orion OB1 association of giant blue stars (luminosity class O and B).
You can see some faint hydrogen alpha red coloured emission in the background.
The actual Witch Head is thought to be a condensation of the diffuse bubble from the shockwave of a supernova explosion.
The denser cloud of gas and dust is illuminated by nearby bright hot blue stars (again classes O and B), principally Rigel which is offscreen to the top right. The dust tends to absorb red and infra-red wavelengths but preferentially reflects bluish wavelengths.
T20 iTelescope in New Mexico. 75 x 6 min subs. 25 x R,G,B processed in PixInsight and Photoshop.
Learning how to clean up noise, CCD column defects and cold and hot pixels in subs with PixInsight Cosmetic Correction tool and reduce background star sizes with PixInsight Morphological Transformation tool.
Witch Head reflection nebula NGC1909/IC2118 [robotic, NM]
Sources seem to differ on whether this reflection nebula is in Eridanus or Rigel but the entire field shown here is a large diffuse molecular cloud of material - the Orion/Eridanus bubble - a giant shell of hydrogen gas and dust blown by the UV stellar wind of the Orion OB1 association of giant blue stars (luminosity class O and B).
You can see some faint hydrogen alpha red coloured emission in the background.
The actual Witch Head is thought to be a condensation of the diffuse bubble from the shockwave of a supernova explosion.
The denser cloud of gas and dust is illuminated by nearby bright hot blue stars (again classes O and B), principally Rigel which is offscreen to the top right. The dust tends to absorb red and infra-red wavelengths but preferentially reflects bluish wavelengths.
T20 iTelescope in New Mexico. 75 x 6 min subs. 25 x R,G,B processed in PixInsight and Photoshop.
Learning how to clean up noise, CCD column defects and cold and hot pixels in subs with PixInsight Cosmetic Correction tool and reduce background star sizes with PixInsight Morphological Transformation tool.