What tree rings can tell us about the spectacular death of stars

The death of a star is one of the most spectacular events in the universe. After millions and often billions of years, the star's fuel supply runs out. Without its nuclear fire to sustain it, the star collapses in on itself, compressing and heating the remaining gas until the pressure becomes so high that the remnants of the star are blown out into the cosmos in a spectacular explosion called a supernova. The explosion is so powerful that modern telescopes can see it half a universe away.