Hi pal,

For become a scientist you have to go for a core branch course in BSC such as physics, mathematics, atmospheric science ,Astrophysics, then you need to pursue your master in a particular core branch, then after that you have to go for PHD. Masters are enough for become a scientist in the core particular subject ,you will have to study hard then you'll get good knowledge of subject.

Hope this will help you.
Good luck.