A doctoral degree is the usual educational requirement to become an astronomer, since most of the work tends to be related to research and development. Since universities offering undergraduate programme in Astronomy are rarely found, one can join for a major/ honours in Physics with Mathematics as a subsidiary subject. Thereafter, take a master's degree in Physics or Astronomy. After the successful completion of MSc, one can do specialization in astronomy leading to Ph. D. which enables one to become an astronomer/ astronaut/ astrophysicist or a scientist/ research officer etc. in the field of space research.
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I don't know whether there is any institute offers B.Sc astronomy courses in India.
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