Hi,
I too have similar idea like you.  I am extremely passionate  in aerospace engineering. But compared to  technology advances in aerospace industry,  in india it still a upcoming sector.  They are only limited opportunities available for handful of students who have good knowledge and expertise in aerospace engineering.  After  clearing gate with valid  score, you can get multiple   opportunities  in public sector. 
At present  compared to private universities,  only few well established institutions like IISC, IITs give a platform to develop and  grow. These are reality  of aerospace engineering,  but if your  seriously  interested in making aerospace  as a profession then  you can choose  it.
Or else in general  sense  , if you want pursue  course in  physics,  then choose  physics  honours which has numerous opportunities  available in research institutes and more over it depends on type of work you are interested in doing

The Scope of Physics. Physics is the study of energy, matter, and their interactions. It's a very broad field because it is concerned with matter and energy at all levels—from the most fundamental particles of matter to the entire universe. Some people would even argue that physics is the study of everything!

There are many job opportunities foraerospace engineers in India as well as abroad. Basically an Aerospace Engineer design, develops, researches, test and maintains the performance of military & civil aircraft, rockets, missiles, weapons systems, satellites, etc.

Aerospace has a huge future scope!! You can go for aerospace if you really strive for it.