A star's explosive death in a supernova left behind this dreamy cosmic scene. Known as N103B, this supernova occurred in a neighboring galaxy to our Milky Way, known as the Large Magellanic Cloud. Because of its relative proximity – in cosmic terms, at least – astronomers can observe this supernova remnant in remarkable detail. The scarlet filaments near the top of the image are the "shock fronts" of the supernova. They show that this explosion isn't expanding as a sphere anymore, but rather as