You can enter the field of space scientist with a little knowledge of math, chemistry, or engineering. Employers such as NASA hire people to work in various laboratories right from college in Work-Study programs to be lab assistants. As you gain more experience, you can be hired full-time as a research assistant. They teach you how to operate high tech analyzers or computers to do research. It doesn't take a Doctor's degree or such to enter the field of space scientist. Then you can obtain higher degrees while you work.