In November of 1572, Tycho Brahe noticed a new star in the constellation Cassiopeia. It was the first supernova to be observed in detail by Western astronomers and became known as Tycho’s Supernova. Earlier supernovae had been observed by Chinese and Japanese astronomers, but Tycho’s observations demonstrated to the Catholic world that the stars were not constant and unchanging as Aristotle presumed. Just three decades later, in 1604, Johannes Kepler watched a supernova in the constellation Ophiuchus brighten and fade. There have been no observed supernovae in the Milky Way since then.
