Other Good Reading: Pi (3.14159...) is used in a lot of mathematical computations. NASA uses it for navigation. Some people have memorized thousands of digits of its infinitely long sequence. But do we really need to know thousands and thousands of digits? NASA JPL’s Chief Engineer for Mission Operations and Science, Marc Rayman, answered that question in 2016, and recently updated it. His answer is understandable and interesting: How Many Decimals of Pi Do We Really Need? from JPL.
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