Astronomy can be viewed as a branch of physics, and in order to go graduate school in astronomy you certainly need an understanding of physics similar to a physics major. Therefore, you will find that at U.S. colleges various Bachelor of Science (BS) degrees with names like "Astronomy" or "Astronomy and Physics." Our program is called "Physics with a concentration in Astronomy/Astrophysics." Regardless of the name, you'll notice they have more physics classes than astronomy classes and are almost identical to a physics major. There will also be lots of math. This major will prepare you for graduate school in astronomy -- or physics or another science for that matter. The course catalog for our major is here.
The fact that U.D. information guides list "Astronomy" as a minor but not a "major" is misleading because what could be called an astronomy major is instead called Physics with a concentration in Astronomy/Astrophysics.
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