Eratosthenes, the Ancient Greek mathematician who calculated the Earth’s circumference

He was a Greek mathematician and the caput librarian astatine the Library of Alexandria who made past implicit 2200 years agone with a elemental yet ingenious experiment.

Eratosthenes became the archetypal idiosyncratic to cipher the Earth’s circumference with singular accuracy, a feat that stands arsenic a testament to the ingenuity of ancient science.

Using the differences successful the space of the sun’s rays astatine 2 antithetic locations, Eratosthenes was capable to estimation the Earth’s circumference. He observed that astatine noon during the summertime solstice successful Syene (modern-day Aswan, Egypt), the prima formed nary shadiness arsenic it was straight overhead.

However, astatine the aforesaid clip successful Alexandria, a noticeable shadiness was formed by a stick. By measuring the space of this shadiness and knowing the region betwixt the 2 cities, helium could usage basal geometry to estimation the Earth’s size.

His method was straightforward: helium measured the magnitude of a shadiness from a vertical instrumentality of a known tallness successful 2 cities connected the aforesaid day. The ratio betwixt the north-south region betwixt the 2 cities and the angles measured gave a ratio that allowed Eratosthenes to cipher the size of the Earth.

Eratosthenes’ calculation of the Earth’s circumference was astir 40,000 kilometers, which is remarkably adjacent to the modern measurement of 40,075 kilometers.

His enactment laid the instauration for geography and demonstrated that adjacent successful ancient times, humanity had a heavy knowing of the world. Eratosthenes’ bequest continues to animate us, showing that curiosity and captious reasoning tin pb to bonzer discoveries.

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