What is the largest explosion you’ve ever heard of or seen? Is it fireworks? Rocket launches? Nuclear explosions? What about up in space? Is it a solar flare? Think again, as the largest explosion in existence is by what are known as supernovas, or supernovae for plural. These cosmic-scale events are so massive that we’ve seen them occur in galaxies other than our own. These massive explosions are even sometimes powerful enough to become black holes. But what causes supernovas to happen?
Aside from the occasional solar flare, the surface of stars looks bland, but there’s a lot going on inside of them. For instance, there is a constant interior battle between gravity and pressure that has to remain at a sort of equilibrium state for the star to successfully perform nuclear fusion, which it’s designed to do. When a star runs out of fuel, hydrogen in the case of our Sun, this equilibrium begins to become unbalanced and eventually gravity wins. If the star is large enough, this results in the star’s core completely collapsing and it explodes into a supernova. While this seems frightening for us on Earth, this will not happen with our own Sun, as its size won’t allow it to explode. Instead, when our Sun runs out of its hydrogen fuel, it will instead start to expand and literally swallow up (at minimum) all the inner terrestrial planets within our solar system. But why do scientists study supernovas?
Supernovas and their after-effects teach scientists about the universe, and specifically how solar systems form. When a supernova happens, its explosion sends its elements around the universe, which eventually coalesce and create new solar systems over the course of hundreds of millions of years. So, while supernovas seem scary—which they are—they are also necessary for the circle of life in the universe.
Sources: Caltech, Department of Energy, NASA
As always, keep doing science & keep looking up!