Stars seem permanent, but they are not. When stars collide, collapse, or explode astronomers leap into action to study the shreds of destruction. The death of stars creates new chemical elements and blasts them into the galaxy to become the stuff of new stars, planets, and, perhaps, living things. The oxygen atoms in the air we breathe, the calcium in our bones, and the iron in our blood were created when stars were destroyed 5 billion years ago.