The National Aeronautics and Space Administration’s (NASA) Astronaut Candidate Program is a textbook definition of a dream job. You travel in a multi billion dollar Space shuttle, stay at the International Space Station and perks include Lunar missions, yes by 2020 NASA will support the development of an outpost on the moon. Did I mention that you get paid for doing all this.
Astronauts are involved in all aspects of assembly and on-orbit operations of the ISS This includes extravehicular activities (EVA), robotics operations using the remote manipulator system, experiment operations, and onboard maintenance tasks. Astronauts are required to have a detailed knowledge of the ISS systems, as well as detailed knowledge of the operational characteristics, mission requirements and objectives, and supporting systems and equipment for each experiment on their assigned missions.

Applicants for the Astronaut Candidate Program must meet the basic education requirements for NASA engineering and scientific positions – specifically: successful completion of standard professional curriculum in an accredited college or university leading to at least a bachelor’s degree with major study in an appropriate field of engineering, biological science, physical science, or mathematics. The following degree fields, while related to engineering and the sciences, are not considered qualify.
Via – NASA