Blue = Facts
Red = Understandings
Green = Questions
This video was about how ancient Greeks thought about our solar system, galaxy and the cosmos, and how their ideas grew.
The ancient Greeks used to believe that the sun and the stars moved around earth for this reason, because earth was in the centre of the solar system. Also, they believed that it had to be the stars and the sun moving (not earth), for if earth was moving we would feel it. How did the ancient Greeks even know about space? At the time, these assumptions was actually a simple mistake to be made. So since they thought this, they drew the solar system with earth in the centre, the moon opposite it and then the sun opposite the moon. Which leaves the stars, which would be rotating around earth in a circle. I understand how beliefs passed down for centuries can really affect what you believe, and how it’s not always the correct assumption.
But one day they found that something didn’t move in a circle but back and forth, so the Greeks had to change the model. Or course they hadn’t worked out what that thing was, but they decided to give it a shot. Astronomers developed more complex models, with happened to have more circles in them. Finally, one day a better model than any was created. This model the astronomers put the sun in the middle of our solar system (which is where it actually belongs).
This model led them to finding out what was the thing that went back and forth across the night sky. This thing was a planet, and it was called Mars.
So after all of this discovery and new information, they should have a pretty good representation… Actually no. At this point in time, they went even close. It wasn’t until Galileo Galilei built the first telescope that they actually got somewhere. When was the first telescope built? It showed things like how Jupiter has four moons.
But this telescope also showed everyone what the real representation of our solar system is.
So now, the current model shows all the planets orbiting around the sun. It also shows that if the sun and stars move across the sky, then the earth must be rotating to make them move.
- The first telescope made was built in 1608 by a German-Dutch lens maker, who went by the name Hans Lippershey.
- The knowledge of space was given to them by other cultures. Chinese Astronomers, Mesopotamian and Zoroastrian astronomers/astrologers and even Indian Vedas mainly helped out the Greeks with their knowledge. Most of the knowledge though was given when Alexander the Great conquered the region, in 331 BCE.