Supernovas

The following citations listed in this article are from What Is a Supernova? | NASA Space Place - NASA Science for Kids.

    Did you know that supernovas are the biggest explosions known to man? A supernova is the occurrence of a star exploding after it cannot take its inward pressures any longer. Dramatic, I know. According to previously cited sources, "When a massive star runs out of fuel, it cools off. This causes the pressure to drop." This means that the battle between gravity and pressure that goes on throughout a star's life ends; gravity wins, by the way. When the star's pressure drops, it creates such a large shock wave that the outer parts of itself explode. These explosions are so bright, they can overpower the luminosity of most galaxies for weeks!

Image Credits: Supernova Remnant of Cassiopeia A Captured by NASA's Chandra X-ray Observatory - Health Thoroughfare

    Supernovas are relatively uncommon, with only a few hundred of them occurring every year. Out of that number, only a few happen in the Milky Way, our galaxy; however, space dust and debris obscure our view of the phenomena. However rare supernovas are, scientists have learned a lot from them, like how to measure distance in space! 

Image Credits: Scientists Observed the Biggest Supernova Ever Seen in the Universe

    Supernovas vary in size, but they are all really, really big. High-mass stars like to go out with a bang, as some say, and this phenomenon fits their needs exactly! This stage of a star's life cycle is definitely one of the most beautiful, with all of the colorful lights and kaleidoscopic heat waves surrounding the core. Speaking of cores, the star's core will be left over after this explosion, and will transform into a black hole, but, as always, we'll talk more about that later!