Aerospace Engineering

Hello Nilay,
Just wait for few weeks. As soon as results of JEE Mains are announced, plenty of sites will tell you about this and also college predictor.
Best wishes.

Hello Himanshu,
In simple terms, aeronautics is study of airborne objects. Aerospace means the industry associated with aeronautics and geo-space means area above Earth's atmosphere.
But what you meant to study will be covered under Astronomy.

Hello Chintan,
Both these institutions are very well known and it's difficult to choose between them. I would advise you to attempt both and get admission wherever you succeed.

Hello Ajay,
IIT M, is a very good place to study. It's aeronautical engineering branch is also well known. It's good to think of it. Start preparing right now for success.

Hello Swastik,
IISc, Bangalore is considered best in India by many. It is a very old establishment and has many well known names as alumni. It's a good launch pad to go to NASA.

Hello Muhammad,
On average, you will be required to spend 5-6 L as tuition and allied fees and whatever your living expenses for four years. Hostels are also available in campus.

Hello Abasalom,
IIT-B has a good name in aerospace engineering. In India, aeronautical & aerospace are almost used as synonyms. Aerospace deals with space & aeronautical deals with aircraft or such similar object. For details, you can get from IIT, Bombay's website.

DIAS has been established recently and admission is either direct or through their own test. Placement is assured as per Institute. Initial packages range from 3-6L.
http://www.dias.net.in/admission.php

Hello Janani,
Admissions in TN are governed by eligibility rules link for which I am attaching. Robotics is a challenging field. Aerospace has perhaps limited job opportunities in India.
http://www.annauniversitycounselling.com/tnea-2016/anna-university-counselling-2016-eligibility/
Best wishes!