Discuss the proofs of Earth’s round shape.
There are several proofs that demonstrate that the Earth is round:
- Observing a ship’s hull: As a ship approaches the horizon, its hull disappears before the top of its mast. This happens because the Earth curves away from us, and the bottom of the ship disappears first. If the Earth were flat, the entire ship would be visible until it became too small to see.
- Lunar eclipses: During a lunar eclipse, the Earth casts a curved shadow on the moon. The shape of the shadow is always circular, regardless of where the observer is on Earth. This is possible only if the Earth is round.
- Travelling in a straight line: If someone travels in a straight line on the surface of the Earth, eventually they will end up back where they started. This is only possible if the Earth is a closed, spherical shape.
These proofs have been recognized for thousands of years and were first studied and explained by ancient Greek scholars, such as Aristotle and Eratosthenes. Today, we have advanced technology like satellites and GPS that further confirm the roundness of our planet.