Astronomers believe that a supernova is a massive explosion signaling the death of a star, causing a cosmic recycling of the chemical elements and leaving behind a pulsar, black hole, or nothing at all. In this story of the life cycles of stars, Laurence Marschall tells how early astronomers identified supernovae, and how later scientists came to their current understanding, piecing together observations and historical accounts to form a theory, which was tested by intensive study of SN 1987A, the brightest supernova since 1006. The study includes all of the latest developments concerning SN 1987A, which astronomers still watch for possible aftershocks, as well as SN 1993J, the spectacular new event in the cosmic laboratory.