Eratosthenes

Definition

Eratosthenes was an ancient Greek mathematician, astronomer, and geographer, best known for calculating the Earth's circumference with remarkable accuracy. His work epitomizes the intellectual achievements of Hellenistic science and mathematics, showcasing the integration of observation, mathematics, and geography.

5 Must Know Facts For Your Next Test

1. Eratosthenes was the chief librarian at the Library of Alexandria, one of the most important centers of learning in the ancient world.
2. He developed a method to estimate the Earth's circumference by measuring the angle of shadows cast by sticks in different locations during the summer solstice.
3. Eratosthenes' measurement of the Earth's circumference was approximately 39,375 kilometers, very close to the modern value of about 40,075 kilometers.
4. His work laid the foundation for future developments in geography and cartography, influencing how we understand spatial relationships on Earth.
5. Eratosthenes was one of the first to use the term 'geography' and is considered one of the founding figures in this field.

Review Questions

• How did Eratosthenes calculate the Earth's circumference, and what does this reveal about Hellenistic science?
  • Eratosthenes calculated the Earth's circumference by comparing the angles of shadows cast by sticks at noon in two different cities during the summer solstice. He measured the angle difference and used simple geometry to extrapolate this to the total distance between the two locations. This calculation highlights the advanced observational techniques and mathematical understanding present in Hellenistic science, as it combined empirical data with theoretical reasoning.
• Discuss the impact of Eratosthenes' work on later developments in geography and mathematics.
  • Eratosthenes' accurate measurement of the Earth's circumference influenced later scholars and geographers, providing a foundation for more accurate map-making and navigation. His integration of geometry with geographical knowledge set a precedent for future mathematicians to explore similar concepts. Additionally, his algorithm for finding prime numbers laid groundwork for number theory, demonstrating how his contributions extended beyond geography into mathematics.
• Evaluate how Eratosthenes’ contributions reflect broader trends in Hellenistic thought and culture.
  • Eratosthenes’ contributions reflect broader trends in Hellenistic thought that emphasized rational inquiry, empirical observation, and interdisciplinary collaboration. His work exemplified how scholars of this period sought to integrate knowledge across various fields—mathematics, astronomy, and geography—demonstrating an early form of scientific methodology. This blending of disciplines highlights a cultural environment that valued knowledge accumulation and intellectual exchange, key features of Hellenistic culture that paved the way for modern scientific inquiry.

Related terms

Circumference: The distance around a circle, which Eratosthenes calculated for the Earth using geometric principles.

Sieve of Eratosthenes: A mathematical algorithm created by Eratosthenes for finding all prime numbers up to a specified integer.

Latitude and Longitude: The coordinate system used to identify locations on Earth, which Eratosthenes contributed to by understanding the Earth's shape and size.