Thor's Helmet Nebula NGC 2359. Photo by Ritesh Biswas, via APOD 9 Jan '24.
A wide-field image of Thor's Helmet Nebula, by Zimmley, 2021.
With their description:
"This lovely emission nebula is NGC 2359, Thor's Helmet or the Duck Nebula.
At the centre of this nebula is a Wolf-Rayet class star (WR7), Wolf-Rayets are stars that have used up most of their hydrogen and are now fusing heavier elements to keep the lights on.
This results in a hell of a lot more heat (up to 210,000 kelvin) and very strong stellar winds. These stellar winds result in the bubble style shape of the core of the nebula, this bubble is interacting with a nearby molecular cloud resulting in the wing like shapes (picture the wake left from a boat).
NGC 2359 is around 12,000 light years from earth and 30 light years in diameter."