Thor's Helmet is a Wolf Rayet nebula in Canis Major. H-alpha (red), NII (green), OIII (blue) 6hrs each in 18 1hr subs. Aspen 16M on 20" PlaneWave on MI-750 fork. Field 36' arc, North on the left.
The central star is so massive and violent that its radiation pressure has stripped away its outer atmosphere. Expelled material is being very strongly excited by hard UV, producing abundant glow in OIII (blue). There is also a surprising amount of NII (green) which is normally found in strongly excited but tenuous gas dredged from the depths. H-alpha (red) maps the location of denser material. The topographical separation of these three components was very strong, resulting in a naturally very saturated picture. Seeing was unusually good and we have not deconvolved the image.
We have consciously departed from our usual "kermit-and-violet" idiom here, aiming to produce an overall measured-to-be-neutral colour balance and white stars.
Grown-ups are invited to compare this image with Bernini's sculpture of Pluto and Persephone at the Villa Borghese outside Rome. There are some resemblances in the lower half of this image to Pluto's muscular arms, and a general feeling of turbulent excess of emotion.
A 2megabyte 1:1 version is here
Best,
Mike n Trish