2 answers
G. Mark’s Answer
Actually, the answer is right there in the list of topics this question was submitted with. Astronauts tend to be scientists and especially engineers. Advanced studies in engineering will require knowledge of higher mathematics, electrical engineering, mechanical engineering, physics and all the related prerequisites the university will require. If you're studying engineering, you're on your way.
Jerry’s Answer
While I am not an astronaut, I have always had a great interest in space exploration and read about it all the time. Based on that, here is my take and recommendation.
Back in the 1960s when the focus was exploration and getting to the moon, being an astronaut required knowing how to operate and guide a vehicle in three-dimensional space , which meant you had to have flying experience - a lot of it and preferably as a test pilot.
Since the 1980s and the era of the shuttle missions and now the International Space Station, most astronauts today are not explorers but researchers who may have some flying experience, but all have additional backgrounds in some area of science that benefits from conducting research in the zero gravity environment of space. Examples of these types of experiments can be found at https://singularityhub.com/2018/12/05/research-in-zero-gravity-6-cool-projects-from-the-international-space-station/. Many are in the fields of medicine, agriculture, biology, so if you become a specialist in one of these fields can become an expert at conducting such experiments, then you can combine that with a passion to fly and become an astronaut.
All that said, there is a big push to get back to the moon and beyond to Mars, so having the skills of the astronauts from the 1960s should be useful again, but the experimentation on ISS will continue not only for experiments that require zero gravity, but also those which will help us learn what we need to know about long distance space travel to be successful traveling to and working on the moon and Mars. To learn more about that I recommend you visit https://www.nasa.gov/press-release/be-an-astronaut-nasa-accepting-applications-for-future-explorers. Best of luck and godspeed!
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