He was the first to precisely calculate the circumference of the earth: Who is Eratosthenes?
Eratosthenes went blind in 195 BC and died a year later at the age of 81, deliberately starving himself.
Eratosthenes was born in 276 BC in Cyrene, present-day Libya, but lived all his life in Alexandria, the capital of Ptolemaic Egypt, until his death in 194 BC. He studied in Athens and came to Alexandria at the invitation of Ptolemy III towards 245 BC, where he spent the rest of his life. Ptolemy III also commissioned him to educate his son. He has never been married.
Eratosthenes of Cyrene (c. 276 BC – c. 195/194 BC) was a Greek polymath: a mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. His work is comparable to what is now known as the study of geography, and he introduced some of the terminology still used today.
The works of Eratosthenes, who was also the director of the Library of Alexandria, named Measurement of the Earth and Memoir of Geography have been lost; however, it is possible to obtain information about these works by making use of the quotations made by geographers such as Strabo and Ptolemy. He is known as a poet as well as a scientist. He was engaged in mathematics, astronomy, and philosophy.
Geography Memoir consists of three parts. In the first part, detailed information is given on Greek history, in the second part the measurement of the Earth and in the third part, detailed information on map making.
Eratosthenes worked in fields as diverse as philosophy, grammar, chronology, and geography. As a result of these studies, very important results were achieved. He greatly benefited from the Library of Alexandria. However, he is best known for his two inventions as a mathematician. The first of the bans is the famous Sieve of Eratosthenes, which is used to find prime numbers and bears his name. The second is a calculator designed for solving the medium proportional problem.
Eratosthenes was the first to accurately calculate the circumference of the Earth. For this purpose, he found the length of the meridian arc between Aswan and Alexandria by calculating degrees. He calculated the length of the meridian arc and the circumference of the Earth using, the Equator and collected his studies in his work called Geopraphika. He is a mathematical geographer who shows the boundaries of the settled areas of the world on a map he has prepared.
A notable achievement of Eratosthenes was his mapping of the then-known world. The map covered the mainland of Europe, Africa, and Asia, including the British Isles. Representing a spherical surface on plain paper was no easy task. It's like placing an orange peel flat on the table. Eratosthenes overcame the difficulty with a highly sensitive and reliable projection using latitude parallels and longitudinal meridians. The map he made was used for centuries in maritime and other fields.
Eratosthenes went blind in 195 BC and died a year later at the age of 81, deliberately starving himself.
Eratosthenes calculated the distance of the sun from the Earth to be 92 million miles (93 million miles to be exact).
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