And when his book became a runaway bestseller, the supposed confrontation between the rational explorer and the dogmatic official was accepted as truth. Over the years—and with the help of Antoine-Jean Letronne , a French author—the legend took hold. Though Columbus never proved Earth was round, he did manage to upset long-held dogma in another way when he ran across a continent nobody in Europe even knew was there. But if you see something that doesn't look right, click here to contact us!
Twice a week we compile our most fascinating features and deliver them straight to you. The idea of a spherical Earth was floated around by Pythagoras around BC and validated by Aristotle a couple centuries later. If the Earth really was a sphere, Eratosthenes could use his observations to estimate the circumference of the entire planet.
Since the difference in shadow length is 7 degrees in Alexandria and Syene, that means the two cities are 7 degrees apart on Earth's degrees surface. Eratosthenes hired a man to pace the distance between the two cities and learned they were 5, stadia apart, which is about kilometres. He could then use simple proportions to find the Earth's circumference — 7. And just like that, a man years ago found the circumference of our entire planet with just a stick and his brain.
Read the original article on Business Insider UK. Join thought-provoking conversations, follow other Independent readers and see their replies. But they had no idea how big the planet is until about B. It was around B.
Like many Greeks, he believed the sphere was the most perfect shape. Possibly the first to propose a spherical Earth based on actual physical evidence was Aristotle B. Around this time Greek philosophers had begun to believe the world could be explained by natural processes rather than invoking the gods, and early astronomers began making physical measurements, in part to better predict the seasons. The first person to determine the size of Earth was Eratosthenes of Cyrene, who produced a surprisingly good measurement using a simple scheme that combined geometrical calculations with physical observations.
Eratosthenes was born around B. He studied in Athens at the Lyceum. Around B. Known as one of the foremost scholars of the time, Eratosthenes produced impressive works in astronomy, mathematics, geography, philosophy, and poetry. Eratosthenes was especially proud of his solution to the problem of doubling a cube, and is now well known for developing the sieve of Eratosthenes, a method of finding prime numbers. Pythagoras' pupils, if not the great man himself, knew that the Earth is round. Traveller's tales of ships disappearing over the horizon and noticing bright stars, such as Polaris, shifting to a higher position in the sky as one journeyed north suggested a curved Earth.
Aristotle about BC , two centuries later, supported the idea of a spherical Earth, Moon and planets because:. This mixture of dogmatic reasons and experimental common sense was typical of him and he did much to set science on its feet. In this section we describe simple models to illustrate some of the imaginative and For 10 Resources.
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