What sort of project or idea would be applicable and meaningful, for a Master's thesis, concerning aerospace and controls?

I am currently an undergraduate student in a mechanical engineering program. I have been accepted into an accelerated degree program, where I will pursue a Master of Science in ME. I have always been interested in aerospace, but my school does not offer it as a formal degree option. However, I view my Master's thesis as a way to branch into this field; how can I combine my interest in aerospace, and more specifically space and orbital applications, with the topic of control engineering?