He is best remembered as the first known person to calculate the Earth's circumference. He was also the first to calculate Earth's axial tilt, which similarly proved to have remarkable accuracy. He created the first global projection of the world incorporating parallels and meridians based on the geographic knowledge of his era. Eratosthenes was the founder of scientific chronology; he used Egyptian and Persian records to estimate the dates of the main events of the Trojan War, dating the sack of Troy to 1184 BC. In number theory, he introduced the sieve of Eratosthenes, an efficient method of identifying prime numbers and composite numbers.
Life and Career
His devotees nicknamed him Pentathlos after the Olympians who were well-rounded competitors, for he had proven himself to be knowledgeable in every area of learning. Yet, according to an entry in the Suda (a 10th-century encyclopedia), some critics scorned him, calling him Beta (Second, or Number 2) because he always came in second in all his endeavors.
Key Facts
- Born: January 1, 276 in Cyrene
- Died: 194
- Field: Mathematics
Legacy and Impact
The influence of Eratosthenes extends far beyond his own lifetime. He fundamentally shaped the foundations of modern mathematics, and his theorems and mathematical frameworks remain foundational to this day.
Though he passed away in 194, his ideas continue to be studied, debated, and built upon by scholars and practitioners worldwide.
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