Kathryn Johnson was seven years old when she saw the original Star Wars movie. Today she’s a professor in the astronomy department at Columbia University in New York City. At first, she wanted to be an astronaut. Instead, she makes a living studying the universe. Johnson feels challenged by her job. She likes that. What advice does she have for aspiring astronomers? Study math and science. And don’t expect to spend all of your time looking at the sky through a telescope.