This composite image of the Tycho supernova remnant combines infrared
and X-ray observations obtained with NASA's Spitzer and Chandra space
observatories, respectively, and the Calar Alto observatory, Spain. It shows
the scene more than four centuries after the brilliant star explosion witnessed
by Tycho Brahe and other astronomers of that era.
The explosion has left a blazing hot cloud of expanding debris (green and
yellow). The location of the blast's outer shock wave can be seen as a blue
sphere of ultra-energetic electrons. Newly synthesized dust in the ejected
material and heated pre-existing dust from the area around the supernova
radiate at infrared wavelengths of 24 microns (red). Foreground and
background stars in the image are white.