NASA employs more than 18,000 people as of 2015, and even more work for the organization as independent government contractors, notes the NASA website. Astronauts only make up a small part of that number; others are lawyers, secretaries, writers, teachers and other professionals.
NASA was founded in 1958, one year after the launch of the Soviet satellite Sputnik. Since then, the organization has directed American exploration and research in space. NASA landed the first humans on the moon in 1969, and there are NASA astronauts on the national space station as of 2015, notes the organization's website. NASA also uses satellites and space probes to explore the solar system.