Thor’s Helmet

Thor’s Helmet (NGC 2539, Sh2-298, Gum 4) is an emission nebula in Canis Major. The powerful Wolf-Rayet star WR7 near the centre of the nebula is causing the gases to glow. That star is thought to be in a brief pre-supernova stage, and could explode in the cosmically-not-too-distant future. This object is thought to be similar to the Bubble Nebula, but the energy from WR7 has blown the gas in Thor’s Helmet into more complex shapes.  Thor’s Helmet also contains much more oxygen structures than the Bubble Nebula. Oxygen gives the teal-coloured structure; hydrogen provides the reds. This nebula contains hundreds of solar masses of ionized gases (the gases that are glowing), along with hundreds of thousands of solar masses of unionized material. The age of the nebula is uncertain, with estimates ranging from 78,500 to 236,000.

This data used to create this image was acquired from Yass, New South Wales, Australia by my friend, expert astrophotographer Martin Pugh. Thank you Martin!

Tekkies: 

SBIG STXL-11002 camera, Astrodon Ha, O3, R, G and B filters, Planewave 17″ CDK, Paramount ME. Equipment control with the SkyX, scripted with CCDAutopilot. All pre-processing and processing in PixInsight, except that master calibration frames were made using CCDStack. Data Acquired by Martin Pugh, from Yass, NSW, Australia. 

3x10m R and B, 4x10m B, 18x20m Ha and 13x30m O3 unbinned frames (total=14hr10m). 
Image scale is 0.63 arcsec per pixel for this camera / telescope combination.

Copyright: Ron Brecher