Waid Observatory

Object: NGC 2359 - Thor's Helmet
Date: Feb. 9-10-11-12-13-14-18, 2015 - Location: Denton, TX
Telescope: ATRC12 - Camera: ST10-XME
Exposure: SII = 7.5 hours - Ha = 6 hours - OIII = 8 hours (30 min. sub-exposures, Bin 2X2)
R, G, and B for star color = 30 min. each
Guided using Innovations Foresight On Axis Guider (ONAG)

Click on the image to view at higher resolution.


Narrowband SII Ha OIII - NGC 2359


NGC 2359 (Thor's Helmet) 1

N2359 is a stellar wind-blown shell nebula around the Wolf-Rayet star HD56925 approximately 15,000 light-years from the Earth.  It is located in the constellation Canis Major.  HD56925 is the bright star located at the center of the main bubble.  This type of star is much more massive and hotter than our Sun.  Wolf-Rayet stars are rare.  Only about 300 are known to exist in the Milky Way. This rarity makes NGC 2359 an interesting object of study and observation.  Wolf-Rayet stars expel material in an extremely violent stellar wind with velocities approaching 2000 kilometers per second.  The ejected material interacts with the gas and dust around the star producing the bubble structure seen in the image above.  The star is ejecting material at a prodigious rate and cannot sustain its extreme behavior for long and it will end its life in a spectacular supernova explosion.

The picture above is a false color image assembled using narrowband filtered data with SII mapped to red, Ha mapped to green, and OIII mapped to blue.  RGB data was overlaid in order to display the stars in a more natural color.

A Bi-Color image consisting of Ha and OIII data may be viewed here.

Copyright Donald P. Waid