ways to enter into space field (excluding jee )

If you are interested in this field so it is advisable to pursue the same from reputed college/university. As per me, you should go for Jee, if you do well in exam then you can get admission in NITs/IITs which will be more valuable as compare to private colleges. But if you dont want to go for JEE then you can try for private colleges if they provide admission on 12th merit basis or through their own entrance test. And yes, the admission criteria of private colleges may vary so you will have to check the criteria of individual college separately.

Good Luck!!!

You can do engineering in Aeronautical branch to go in space field. Many Private and Government colleges provide this course, you can check list of  all colleges below:

http://www.engineering.careers360.com/aeronautical-engineering/colleges