Science

Karpagam Academy of Higher Education provides M.Sc in astronomy. https://kahedu.edu.in/?page_id=197.

If you have already submitted the form, then changes won't be possible now. You can drop a mail or call the concerned authorities regarding the same.

The eligibility is, candidate must have completed B.Sc with Physics from a recognized University. The classes schedule is normal from around 9.30 AM to 5.00 PM.

Sorry, M.Sc horticulture is not offered by this university.

Yes, it is a good enough book. Yet, if you want, you can refer to these books as well:
Horticulture at a glance by Dr. A. S Selaria
Text book of pomolgy - TK Chattopadhyay
Fundamentals of agriculture by Arun katyayan.

Hello Shrankhala,It is indeed great to hear from you that you have a great dream of becoming an astronaut. Actually speaking, anyone can become an astronaut provided his / her speciality is required in space. US has wide spectrum of professions from which astronauts are selected. In Indian perspective, the choice is going to remain within fighter pilot category unless ISRO thinks differently. So, it all depends on right person at right place that will make him / her an astronaut. Best wishes to you.

You can refer to this link for details: https://www.shiksha.com/university/tezpur-university/tuee-exam-syllabus?course=991.