Nebula image was taken with 2" Chroma narrow band filters (OIII, Ha, SII). Stars image was taken with 2" Chroma filters (Red, Green, Blue).
A quick Google search shows the following -
Thor’s Helmet Nebula (NGC 2359) is an emission nebula in Canis Major, located roughly 12,000 - 15,000 light-years away. Shaped by intense stellar winds from a central Wolf-Rayet star (WR7, also cataloged as HD56925, HIP 35378, and TCH 5407-3417-1). This 30-light -year-wide "cosmic helmet" features wing-like structures and glows brightly in OIII and Ha.