Astro Imaging & Dark Sky Preserve
This is the Pinwheel Galaxy M101 or NGC 5457 located in the constellation Ursa Major (The Big Dipper)
M101 is slightly larger than our galaxy with a size of about 170 thousand light years across. It is about 25 million light years away from us. It shines at about magnitude 9.0 and is visible with a good telescope. However to observe the detailed arm structures seen in my image, one requires a very large telescope. I was using a 17 inch Truss scope for this image.
As you can see by the image, M101 is an asymmetrical galaxy. Its spiral arms being forcefully bothered by adjacent neighbouring satellite galaxies.
The soft pink hues situated in the arms of the spirals, are hot star forming regions and are rich in H II emissions. These regions were imaged here with the aid of other narrow band techniques.
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