6 ms·

5% error is incredible. I wonder what Eratosthenes thought of his own measurement. Did he believe it was accurate? Or questioned if unknown factors could have t

5% error is incredible. I wonder what Eratosthenes thought of his own measurement. Did he believe it was accurate? Or questioned if unknown factors could have thrown off his calculation?

oxygen_crisis 3y ago
He measured it in "stadia" and there was no consensus about exactly how long a stadion was. The definitions ranged widely, from ~150m to ~210m. The low error assessment comes from magnanimously (but baselessly) choosing to use the definition of a stadion which assigns Eratosthenes the lowest error. https://en.wikipedia.org/wiki/Stadion_(unit) https://en.wikipedia.org/wiki/Stadion_(unit)
- whatshisface 3y ago
  >An empirical determination of the length of the stadion was made by Lev Vasilevich Firsov, who compared 81 distances given by Eratosthenes and Strabo with the straight-line distances measured by modern methods, and averaged the results. He obtained a result of about 157.7 metres Sounds like there are other lengths given by Eratosthenes which could be used to tell what he meant by one stadion.
  - deleted 3y ago
    [deleted]
- DiogenesKynikos 3y ago
  Even if he only measured Earth's radius with 50% accuracy, that's still pretty impressive for the 2nd Century BC.