Strange 'reverse shock wave' supernova is exploding in the wrong direction - Livescience.com

Part of the shock wave is shrinking rather than expanding.

A colorized image of Cassiopeia A based on data from the Hubble, Spitzer and Chandra space telescopes. (Image credit: NASA/JPL-Caltech) A powerful shock wave traveling through a cloud of gas left be… [+6263 chars]

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