Who was Eratosthenes and what did he do?

Who was Eratosthenes and what did he do?

194 bce, Alexandria, Egypt), Greek scientific writer, astronomer, and poet, who made the first measurement of the size of Earth for which any details are known. At Syene (now Aswān), some 800 km (500 miles) southeast of Alexandria in Egypt, the Sun’s rays fall vertically at noon at the summer solstice.

What did Eratosthenes discover?

Eratosthenes may have been the first to use the word geography. He invented a system of longitude and latitude and made a map of the known world. He also designed a system for finding prime numbers — whole numbers that can only be divided by themselves or by the number 1.

Why was Eratosthenes called beta?

He believed that heavy rains near the source of the Nile was the cause of Many of Eratosthenes’ peers nicknamed him “Beta” which is the second letter of the Greek alphabet, indicating that he just fell short of first place.

How accurate was Eratosthenes?

Values between 500 and about 600 feet have been suggested, putting Eratosthenes’ calculated circumference between about 24,000 miles and about 29,000 miles. While not exactly correct, these assumptions are good enough to make a quite accurate measurement using Eratosthenes’ method.

What is the main ideas of Eratosthenes?

Eratosthenes saw that the heavens seemed to rotate once a day around Earth. The axis of rotation formed an imaginary line from the North Pole to the South Pole through Earth’s center. Eratosthenes calculated the tilt of Earth’s axis relative to the plane of its equator with good accuracy.

What were the first Greek dramas called?

The playwright Aeschylus added a second speaking role, called the antagonist, and reduced the chorus from 50 to 12. His play ‘The Persians’, first performed in 472 BC, is the oldest surviving of all Greek plays.

Who is the father of Eratosthenes?

Aglaos
The son of Aglaos, Eratosthenes was born in 276 BC in Cyrene. Now part of modern-day Libya, Cyrene had been founded by Greeks centuries earlier and became the capital of Pentapolis (North Africa), a country of five cities: Cyrene, Arsinoe, Berenice, Ptolemias, and Apollonia.

How did the Greeks know the size of the earth?

In the third century BCE , Eratosthenes, a Greek librarian in Alexandria , Egypt , determined the earth’s circumference to be 40,250 to 45,900 kilometers (25,000 to 28,500 miles) by comparing the Sun’s relative position at two different locations on the earth’s surface.

What two things is Eratosthenes most famous for?

Eratosthenes was a Greek mathematician who is famous for his work on prime numbers and for measuring the diameter of the earth.