In this episode, we continue learning about the Hellenistic Age in which Greek thinkers made many important advances in the fields of mathematics and astronomy. Part 2 features the stories of Eratosthenes, Apollonius of Perga, and Hipparchus. These three men contributed significantly to our understanding of the world and universe that surrounds us, including measuring the circumference of the Earth using shadows and laying the groundwork for modern trigonometry.