Hey, to become an astronaut at NASA you would have to qualify some basic requirements as follows:

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  At the very basic a bachelors degree in engineering, biological science, physical science or mathematics is required. You can even have a masters or a pH.D.
  


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  A 20/20 vision either naturally or with corrective lenses.
  


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  Blood pressure not more than 140/90 in a sitting position.
  


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  A height between 62 - 75 inches(5.1 - 6.3 feet).
  


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  And should have a good shape and maintained health.
  


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  Lastly citizenship of the country in which you want to enroll into a astronaut program.
  

If u have all these qualities then you are eligible to become an astronaut. But apart from that you need to have pure determination and total hard work as getting a job as astronaut is not an easy task. No matter how many times you fail you gotta keep trying till you fulfill your destiny. I have provided a link below to gain more knowledge about the content. Hope this info was of help.


Best of luck for your career.




https://www.google.co.in/amp/s/amp.space.com/25786-how-to-become-an-astronaut.html