Majoring in Astrophysics at university in Australia but my dream is to work at Nasa. Do I have to be an American citizen to work at Nasa in America? I'm 2nd year BA student in Biotechnology, but it wasn't my first choice. I wanted to major in Environmental Science but it wasn't available at that time. My dream is to work with NGOs like Greenpeace What post grad should I study in order to do so and what can I do to increase job opportunities?