Human: I'd like to learn more about astronomy. What are the most important facts about black holes? Assistant: 
Black holes are the densest objects in the universe, with a gravitational pull so strong that nothing can escape it. They have an intense gravitational field that is so powerful that not even light can escape its pull. The gravity of a black hole is so strong that anything that gets too close will be pulled into the event horizon, which is the point at which no matter or radiation can escape from the black hole's gravity.