Astronomy

You have to give JEE mains and advance exams. If you will score more than cut off and nearly merit list, then you are able to choose B. Tech in Indian Institute of Space Science and Technology.

First of all, I am very sad to say that with such a percentage, you cannot think of getting admission for B.Sc in astrophysics. This field demands a percentage of 80% or above. If you want to fulfill your dream, please go for 12th improvement examination though its a very tough decision to take think twice what you want from yourself. If you have very strong determination regarding this prospect, please go with it. God with and you yourself will definitely help! Looking forward for your reply with your decision to guide you further. Good luck.
I keep a strong faith on you!

If you want to join ISRO, then every year ISRO conduct their own exams which you have to clear it.

You can check the this year's category wise opening and closing ranks of various IITs at
http://jam.iitb.ac.in/round_3.pdf
and for more information about IIT JAM, visit:
http://jam.iitb.ac.in
Best of luck.

Hi Sarjeet, Candidates must have a Bachelor's degree in Physics or Mathematics or CSE or EE or ME. Minimum Eligibility to Apply: 55% graduation. For further details, refer below
https://www.shiksha.com/science/course/m-sc-in-astronomy-indian-institute-of-technology-Indore-291586.

Basic qualification is 10+2 with Physics, Chemistry, Mathematics subjects. You can choose B.Tech in Aerospace engineering. There are entrance exams, which will decide the seat allotment. Another option is B.Sc. Physics with Astronomy or astrophysics specialisation and then M.Sc. and go on to do Ph.D. with astronomy or astrophysics specialisation.