Eli5: How did people in olden days (such as Galileo) come to the conclusion that the earth was spherical without very advanced technology?

Question

Eli5: How did people in olden days (such as Galileo) come to the conclusion that the earth was spherical without very advanced technology?

In: Physics

Answer 1

Here’s a video explaining how simple experiments can show that the Earth is a sphere, without modern technology.