Black holes are not monsters waiting to devour the galaxy Almost everyone has heard the term black hole in science fiction movies or popular television shows, but surprisingly few people know exactly what these mysterious cosmic objects actually are. Try refreshing your browser, or Black holes are not monsters waiting to devour the galaxy Back to video We apologize, but this video has failed to load. The most common type, known as a stellar black hole, forms at the end of the life cycle of a massive star. Shortly after, a physicist named Karl Schwarzschild used those mathematical equations to show that a black hole could theoretically exist. Article content Ultimately, black holes are not malicious space monsters waiting to devour the galaxy.