Is it possible to go into college for 4 years and become an astronomer?

I love astronomy and want to become an astronomer. I am only 11 years old, and don't put in your answer that college is a long time from now. But any way, I want to have a husband and kids, but by the time i get out of college, i'll be 27 or 30 years old, and i don't want to be that old when i marry and have kids. So, i thought that the solution would be to go to college for 4 years. Is that possible? Could i still study astronomy?