Famous Supernovae Still Echo Across the Milky Way

In 1572, the Danish astronomer Tycho Brahe observed and studied the explosion of a star that became known as Tycho's supernova. More than four centuries later, Chandra's X-ray photograph of the supernova remnant shows an expanding bubble of multimillion degree debris (green and red) inside a more rapidly moving shell of extremely high energy electrons (filamentary blue). Astronomers have detected a light echo from this supernova, meaning they can see the light from the explosion itself 400 years later. Credit: NASA/CXC/Rutgers/J.Warren & J.Hughes et al.