Astrophysics and Aerospace Engineering in Graduate School?

I am just a freshman in college but I am really confused in what to do. I was thinking about doing a double major in physics and mechanical engineering. Would that get me ready for graduate studies in astrophysics and aerospace engineering?

Also, I wanted to know, is that a good career? I heard you have to move a lot and the pay isn't that good. Well of course it depends on what you end up doing but I know it's very competitive. I've thought about changing my major so many times but I've always wanted to do this and I feel like I should go after what I am passionate about. Can someone help me?