what course should i take after twelvth to be an astronaut

You must go for graduate course in Aeronautics or in astronomy, there has to be a strict training and sound preparation for getting through,.......you may opt some of these – universities in Michigan, Florida or Iowa, but that makes one thing clear that you may have to spend a lot of money, to save money and time you may choose any Indian institution that helps you live your dream by joining a course in aviation and does pay toll on your pocket, you may consider – BITS Pilani,..........LPU, Phagwara,..........JNU, Jaipur,.........Jadavpur University, Kolkata