Sh2-129 and Ou4 the Squid Nebula.

Since 2011, when the French amateur astrophotographer Nicolas Outters discovered Ou4, the Squid Nebula, I have wanted to photograph it, but until this summer I had not had the chance to do so. 

The image covers a field of almost two degrees (at 1.69"/pixel) in Cepheus. The red hydrogen emission region in the image is Sh2-129, the Flying Bat nebula. The blue-green emission that comes from ionized oxygen atoms is Ou4, the Squid Nebula. This giant nebula spans more than one degree of the night sky, which probably represents the largest angular extent found in a planetary nebula. The peculiar Squid shape is created by the flow of material driven by a triple system of hot, massive stars, catalogued as HR 8119 (HD 202214). 

For this image I had to accumulate a lot of exposure, 62 hours in total (43 of which were with the OIII filter). The image is presented in HaOO palette (with the stars in RGB from my previous image of the area). The balance of the colors was adjusted to my personal taste with the help of the NarrowbandNormalization module in Pixinsight.

The second image contains only the OIII filter data, and I present it to further highlight the nebula.

Click on the images for a higher resolution version, or go to the Gallery section for complete exposure details.

Image processing: Pixinsight.

Observatory automation and remote operation with Talon6 

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