I wanted to know if it would be at all possible to get my bachelor's degree in theoretical astrophysics at the time I'm 18. I'll be 16 when I graduate this year from high school, and I'm taking 2 dual credit college classes (the max a student can take). I'm also taking AP Physics and AP Chemistry, and from what I understand is that if I make a high enough scores on the final exams, I will have the choice of getting some college hours from those scores. I plan on going to college the summer I graduate, and going to college year round after that. My birthday is the 23rd of September. Would it be possible to get my bachelor's degree when I'm 18? Also, if I want a PhD in Theoretical Astrophysics, do I have to get Bachelor's, Master's, and then a PhD?