In Kerala, your best option would be MS Astronomy and Astrophysics at IIST Thiruvananthapuram. IIST, following Footsteps and Guidance of ISRO in Research, Technology and Outlook towards Space Science and Astrophysics, besides having best in class faculty, infrastructure and project prospects with ISRO and related Research Facilities.

For more information about IIST MS Astrophysics and related Entrance Exam/Procedure do follow the link below

https://www.careers360.com/university/indian-institute-of-space-science-and-technology-thiruvananthapuram/ms-astronomy-and-astrophysics-course

For more information about Astrophysics and related Courses do follow the link below

https://www.careers360.com/courses/astrophysics-course