This image comes from a very deep Chandra observation of the Tycho supernova remnant, produced by the explosion of a white dwarf star in our Galaxy. Low-energy X-rays (red) in the image show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave, a shell of extremely energetic electrons .
Thanks, Chandra the X-Ray Observatory!
Source: http://chandra.harvard.edu/photo/2011/tycho/
2009 Composite: http://chandra.harvard.edu/photo/2009/tycho/