Depending on their background, astronauts train as pilots or mission specialists. You also need to be in top physical condition, and have great stamina. Maintain an excellent academic record in your undergraduate and graduate studies.
Many astronauts have doctoral degrees.
Choose a scientific field for your bachelor s degree that you can use if you become an astronaut. Possibilities include medicine, biology, chemistry, physics, aerospace engineering and mathematics. Make certain you have at least three years work experience in your field before applying as a mission specialist. An acceptable substitution might be a two-year graduate degree with one year of experience. You ll have to pass the strict NASA physical as a basic qualification.