Thor's Helmet in Canis Major is about
15,000 lightyears distant.  A large
bright star near the helmet's center
has created this interstellar bubble
by the force of its "stellar wind".
However, this star, known as a
Wolf-Rayet star, may go supernova in
the relatively near astronomical
future. In the meantime, we can
continue to enjoy images of NGC
2359...

This image was created by first
assembling a simple RGB from the 2
hours/channel RGB data. The Ha
data was layered over the red in
Photoshop's lighten mode; the same
with the OIII data for the green and
blue channels. This allowed us to
create an image with RGB stars but
enhanced nebula detail from the Ha
and OIII data.

Then a composite (Ha+OIII) layer was
pasted over the (R+Ha)(G+OIII)(B+OIII)
image. The opacity of the composite
layer was reduced somewhat to allow
the RGB stars to shine through,
though we deliberately kept the star
appearance relatively subdued, so as
not to detract from the nebula

16" RCOS @ f/11.3
Apogee U9 imager
SBIG 402 guider

Ha/OIII/RGB composite

Ha =   30 min x 24, 1x1
OIII=   30 min x 16, 1x1
R=     15 min x 8,   1x1

G=  
   15 min x 8,  1x1
B=  
   15 min x 8,  1x1

Data acquired at
CTIO

Processed with CCD
Inspector,  
Maxim,
Registar, Sigma
Combine, Neat Image,
Adobe PS
, and PixInsight
Thor's Helmet, NGC 2359
Click on image to enlarge