Answer: An astrophysicist is more concerned with the laws that govern the origins of stars and galaxies.
Step-by-step explanation:
Astrophysicists like Raj Koothrappali in the Big Bang Theory differ from astronomers in that they study the general universe to find out the laws that govern it as well as how it originated and evolved.
Astronomers on the other hand is more specific in their study of the universe and so you will find them focusing on certain planets or galaxies.