re: Can someone please explain Astrophysics

Sorry, this isn't explainable in a blog post any more than one can explain binary options in a similar space. You just have to do the coursework (and lab work), there really isn't a shortcut.

Oh, and math. Lots and lots of math. But if you get option pricing models then the math used in Physics can be learned. It's one reason why the first Wall Street quants were mostly physicists, there's a fair amount of overlap in the techniques.