A black hole is an extremely dense and compact astronomical object with such strong gravitational pull that nothing—not even light—can escape from it. According to Albert Einstein’s theory of general relativity, when a mass becomes compact enough, it will inevitably form a black hole. The boundary beyond which nothing can escape is known as the event horizon. While a black hole significantly influences any object that crosses this boundary, it does not exhibit any detectable local features, as described by general relativity. In many respects, black holes behave like perfect black bodies, absorbing all light without reflecting any. However, quantum field theory in curved spacetime suggests that event horizons emit what is known as Hawking radiation, resembling the radiation of a black body. The temperature of this radiation is inversely related to the black hole’s mass, meaning that stellar black holes would emit radiation at temperatures just billionths of a kelvin—far too faint to detect with current technology.