This is the massive spiral galaxy NGC 2403, in the constellation of Camelopardalis. I discussed this amazing galaxy in Episode 46 of Star Hopping.
Image Data: Canon 60D with an Astronomic CLS in-body filter, at the prime focus of the 18″ KPO Reflector. 33 subframes of 120 seconds each, yielding a total integration time of 66 minutes. Captured in Nebulosity, processed in StarTools, and finished in Aperture.
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