2 or any SAT subject tests right after the ACT?

I’ve never actually heard of anyone take the subject tests right after the ACT, and I’ve refused to ask anyone because I was confused. Well, I’m taking the ACT next year as a junior, and since senior year is going to be a lot of hard work in regards to hard and rigorous classes, I’m planning on taking at least 2 subject tests (Literature and Math Level 1). Can someone please tell me if it is possible to take the sat subject tests right after the ACT? Thank you.