Like all of them rightly mentioned... there's no need to rush. If your son wants to get into space studies and is already doing well in science, then there's nothing to worry. All you need to do is find out colleges which offer astrophysics/space studies and enroll him there once he is through with his schooling. Meanwhile you can send your kid to a Space Camp. This will give him an up-close exposure to the field, which will help him decide if he is really willing to take up the subject in future. One that i know of is Space Camp India. They take kids to The U.S Space and Rocket Centre at Huntsville, Alabama. Their programmes integrate both textual concepts as well as hand-on training on space studies. Why don't you check out their website - http://spacecampindia.com/ I am sure it'll be an enriching and useful experience for your child.... Hope that helped!