UC Boulder would be a good choice nearby. Keep in mind there aren't really any jobs in astronomy if you don't have a PhD in the subject, and if you want to get a PhD in astronomy or astrophysics, you should be majoring in physics - astronomy, math, and computer science courses are useful/necessary as well, but the physics major is essential for applying to grad schools. Astrophysics majors typically do NOT require you to take as much physics as you will need.
Other great schools are the ivies, Berkeley, CalTech, MIT, U Arizona, UT Austin, U Chicago, UCLA, UC Santa Cruz, Ohio State, U Michigan, Rice, U Washington, U Wisconsin, U Virginia, UMass Amherst, and many more.
