Astrophysics/astronomy?

In the undergraduate level astrophysics is harder and involves more math and physics. But as you get to higher levels I don’t think they’re very different. The biggest difference is probably the physics and math required for astrophysics is a bit higher level. I took an honors astrophysics course at University of Michigan and it wasn’t very hard. You did a little bit of differential calculus and other than that mostly algebra.

We helped kids in astronomy and it was unit cancellation type math.

I also took a general relativity course, and in either field you’d probably need to be very familiar with the laws of gravity, so you’d be looking at various forms of calculus, vector and tensor analysis and a lot of various math like spherical coordinates.

Any school that has a decent science program will probably have a good astrophysics program, but I don’t think there are very many big schools for astronomy. Michigan’s program was small, but I’m sure they do a ton of work with the physics program and that was very well sustained.

suggestion to you is formerly you dedicate your self to this, you will desire to circulate to universities and refer to different PhDs approximately their careers in astrophysics. They know first hand what to assume and could be greater advantageous than prepared to talk with you.