Last night (the 10th May 2026) we had one of those really clear and dark spring nights. It was marvellous! The Moon was one day past last quarter and didn't rise until 03:03 BST this morning. One of the suggestions that came up on the Atlas in the Dwarf 3 was Coddington's Nebula (IC 2574) in Ursa Major which I had never heard of before, so I decided to try it. This is what I obtained after 432x15s (1 hour 48 minutes) of observation:-
The nebula is the object in the centre of the image. The first frame was taken at 22:36 BST and the last at 00:47 this morning. The astro filter was employed and the gain was 60. Auto parameters were used in Stellar Studio. I have increased the saturation of the image in Photoshop and binned it x2. Here is a close up of the object using the unbinned data:-
This is not actually a nebula in our galaxy but a galaxy in its own right. This dwarf spiral galaxy was discovered by Edwin Foster Coddington in1898 and is an outlying member of the M81 group of galaxies. This galaxy looks like a nebula because of the large amount of star formation that is taking place within it and that gives the galaxy its blue and red appearance (the red colour coming from HII regions). Interestingly, the visible component of this galaxy contributes very little to the overall mass of the galaxy meaning that the majority of the mass is in the form of dark matter (this accounts for 90% of the mass at the last measured velocity point - see Martimbeau and Carignan 1994). This is true of most dwarf spiral galaxies and makes them ideal objects to test theories of dark matter.
All text and images © Duncan Hale-Sutton 2026
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