The Philosophers of ancient Ionia

Chapter 4: Aristarchus of Samos and the Heliocentric Model of

the Solar System or how Aristarchus met Kopernicus!

How difficult is to understand today, that a simple thing as the fact that the earth is moving round the sun and not the opposite, 2.000 years ago was an heretic point of view of our universe? Despina and Mateusz knew much about later scientists that proved this simple thing but they didn’t knew that ancient people, without telescopes or other astronomical instruments, had such a knowledge of the universe…

But did ancient people knew that the Sun is in the centre of our Solar System? Who was Aristarchus?

Did he prove it?

Dear children, Aristarchus did much more than just say that the Earth is rotating round the Sun! He is the first person on record to maintain the following axioms: The rotation of the stars is due to the Earth rotating on its axis! The earth follows a circular orbit around the Sun. The Sun is fixed at the centre of the universe, and the stars are fixed in the heavens.The stars are a vast distance away, otherwise stellar parallax would be easily observed. The Sun is one of the fixed stars and last but not least, the moon rotates around the Earth!

How difficult is to understand today, that a simple thing as the fact that the earth is moving round the sun and not the opposite, 2.000 years ago was an heretic point of view of our universe? Despina and Mateusz knew much about later scientists that proved this simple thing but they didn’t knew that ancient people, without telescopes or other astronomical instruments, had such a knowledge of the universe…

He thought all of these things? He must be great then! But is he here, like the other ancient scientists we saw?

Aristarchus was born on 310 BC in the island of Samos. He died on 230 BC. He was not only an astronomer but a mathematician as well. He comes from time to time from Samos, to visit us… We can search for him. If he is here, he is probably with Euclid and Archimedes, his friends. Archimedes was his main successor and most of the information today’s people know about Aristarchus, comes from him and from Plutarch. But if you want to find Aristarchus, we have to hurry… It’s getting late, the sun is setting….

So, Despina, Mateus and Homer start asking for Aristarchus… None had seen him… And the sun was close to set… Despina and Mateus didn’t know that they had to live just after sunset… It was the law of the city of Ancients… If they didn’t leave by that time they had to stay there for ever…

Oh… what are we going to do? Can we stay for the night? We’d like to see Aristarchus so much! There are so many things he can tell us!

We could even inform he about all the next generations made… That we conquered space! That we stepped on the Moon!

Dear children… you have only a few minutes… you can't stay here. But have faith. We’ll try one more place that Aristarchus may be…

And this time Homer was right…. They found Aristarchus on a hill, watching the sunset! The children were so happy that they couldn’t even speak… But the old scientist knew that they were there and he spoke first!

Look at the sun setting… I spent my life to proof that it is just a fixed star and this Earth that we live on it, revolves about the sun…

And this time Homer was right…. They found Aristarchus on a hill, watching the sunset! The children were so happy that they couldn’t even speak… But the old scientist knew that they were there and he spoke first!

‘Universe' is the name given by most astronomers in my times, to the sphere the centre of which is the centre of the earth, while its radius is equal to the straight line between the centre of the sun and the centre of the earth. But I think that the universe is many times greater than the 'universe' just mentioned. My hypotheses are that the fixed stars and the sun remain unmoved, that the earth revolves about the sun on the circumference of a circle, the sun lying in the middle of the orbit, and that the sphere of fixed stars, situated about the same centre as the sun, is so great that the circle in which he supposes the earth to revolve bears such a proportion to the distance of the fixed stars as the centre of the sphere bears to its surface.

I also determined that the Sun is about 20 times as distant from the Earth as the Moon, and 20 times the Moon's size.

“it is supposed that the stars and the sun stay unmoved and that the earth is turning on a circle round the sun, which is in the middle of this circle”

Oh… yes! Well, many-many years passed before that happened, but now everybody knows it! You know, a very important scientist of my country, Poland, Copernicus, gave his own fight to pursued people of the heliocentric theory!

Despina and Mateus had so many things to ask and even more things to tell to Aristarchus…. But the sun was setting…. Aristarchus smiled to the children. He had also some questions to ask…

Do you know if people in the future believed my theories? Was there anyone to make them understand that our small Earth is not the centre of the Universe?

Bye Aristarchus! This was the most interesting afternoon we ever had in our lives! We met so many fabulous people! Poets, mathematicians and all kinds of scientists! We have so many things to tell everyone when we go back! We thank you all!

Despina and Mateus had so many things to ask and even more things to tell to Aristarchus…. But the sun was setting…. Aristarchus smiled to the children. He had also some questions to ask…

These are really good news that you brink me children. Now I can rest… But you… You must hurry! The sun almost set… Homer will show you the way back….

Despina and Mateus came back to the City… They were modern children now. They had to say good bye to all their new friends… Sophocles, Aeschylus, Euripides, Aristophanes, Eratosthenes, Hypatia, Anaxagoras, Anaximander, Anaximenes and Aristarchus…

Good bye Homer! Thank for everything! But can you tell us one more thing??? Where you were born???

Haha… Well, I was born…..

Bang!!!!

Mateus! We are back! What happened? Was it a dream? I saw Homer, the ancient poet my uncle told us about!

I remember Aristarchus! And many others! That was really a trip to the City of the ancients!

Ah! Did you heard what Homer said about his birth city?

I don’t remember that!!!! But would you like to listen to the story of Copernicus? Well…..

I will tell you a story about the most renowned citizen of the town of Torun all over the world. You must have heard about him earlier. Of course, this is Nicholas Copernicus- the author of heliocentric theory!…