1 answer
Daniel’s Answer
Astronomy is a college major. I see 71 colleges in the country that offer astronomy and/or planetary science. That search is here: http://nces.ed.gov/collegenavigator/?s=all&p=40.0201+40.0203+40.0299&l=93&ct=1+2&ic=1
To prepare, study all of the science classes you can in high school. Study mathematics and statistics; they'll be important in a college science field. And read as much as you can about astronomy! There are many space scientists on Twitter. Read their thoughts and write to them!
https://twitter.com/AstroKatie
https://twitter.com/AstroSamantha
https://twitter.com/aomawa
https://twitter.com/berkeleyjess
And read through https://twitter.com/hashtag/GirlsWithToys?src=hash which shows many space scientists at work.