Cassiopeia A (Cas A), a supernova remnant located 11,000 light years away, is the second youngest known remnant in the Milky Way Galaxy. Although very well studied, Cas A has kept its origins hidden through the veils of time ? until now. A group of international astronomers from the Subaru Telescope, Max Planck Institute of Astronomy (MPIA), and University of Arizona's Seward Observatory came together to finally determine the history behind Cas A.

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More info: Subaru telescope web page