Ancient Greeks knew the Earth was round

[Tsontos]

Ancient Greeks knew the Earth was round

July 26, 2006

It always seems amazing how much ancient people knew without using the sophisticated methods of modern times.

For example, the Greeks knew not only that the Earth was round, but also just about how big it was. And that was 2,500 years ago!

How could they possibly know this? We might imagine using pictures from space, or plane trips around the world. But in ancient times?

Let's use their reasoning. The stars appear higher the farther south you go. We use that fact when we go south in winter. It's warmer in Florida because the sun is higher.

That shows that the Earth is round — if it were flat, the sun would be just as high everywhere.

For example, the sun is higher in New York than it is in Rutland. The details: at noon, it's about 3-1/2 degrees higher, and New York is 250 miles south of Rutland.

That difference of 3-1/2 degrees is about one-one hundredth of 360 degrees. So the 250 miles must be about one-one hundredth of the distance around the Earth.

So the distance is 100 times 250 — 25,000 miles, which is very much what we're told in school.

That's how the Greeks — using different cities, of course, but the same method — knew just how big our world is. And now we do, too!

Keep looking up!


http://www.rutlandherald.com/apps/pb...22/1024/NEWS04

I read somewhere that they "computed" the earth's perimeter and their figure was very close to the real one (<5%, if I remember correctly). But I have forgotten the name..

[Tsontos]

It was Eratosthenes
http://turnbull.mcs.st-andrews.ac.uk...tosthenes.html
http://astrosun2.astro.cornell.edu/a...atosthenes.htm
http://www.grenzstein.de/history/era/eratosthenes.html (in German)


According to the last site, which is more detailed reg. the earth-cicumference calculation, Eratosthenes came to the result that it was between 250.000 and 252.000 Stadia. According to which stadium one takes (apparently there exist mainly 3, the greek one coresponding to 148,5m, the aegyptian 157,5m and the roman 185,6m), one gets a result between 37400 km and 46800 km, a deviation between -7% and +17% (the meridian is calculated nowadays as 40008 km.)


Sometimes I wonder, whether people from our generation will ever be remembered after 2000 years with such respect for their achievements in their chosen field.
Probably not..

[Ehetlaios]

If you ever read Plato's "Timaios" you will be speechless. It is a conversation regarding the world's construction by a being mentioned as "God" and that is exactly where people like Liakopoulos step and shout "Plato was the first christian!".

Anyway, the conversation takes place between Socrates, Kritias, Ermocrates and another person whose name I don't remember, and Plato through Kritias says that the earth is round, it moves around the sun and around itself and gives away knowledge that by that era's standards we think it would be impossible to know.

[olvios]

i ve read it the fact that the world was round was known to the greeks among many scholars and also taught in many ancient greek universities

[Lakonian]

Hey guys, juts do add to this, i was watching GetAway, an Aussie holiday show, if your Australian youll know what im talking about, anyway, the night befoe they were showing the meteora( the mountains where the churches were built on there peaks to avoid the barbarians), well the host qouted that these monks believed the earth was still flat? ok i couldnt help but laugh, but then again i couldnt help but ponder, could it be that the monks didnt have any mathimatical knowledge or the ancient texts which were copied by the arabs and so on?

I know many of them were destroyed by the fanatics but come on they surely knew the earth was round right? Has anybody got any sources?

Starbo, Aristotle,Plato , Socrates many ancients knew the earth was round

[Ehetlaios]

Originally Posted by Lakonian

Hey guys, juts do add to this, i was watching GetAway, an Aussie holiday show, if your Australian youll know what im talking about, anyway, the night befoe they were showing the meteora( the mountains where the churches were built on there peaks to avoid the barbarians), well the host qouted that these monks believed the earth was still flat? ok i couldnt help but laugh, but then again i couldnt help but ponder, could it be that the monks didnt have any mathimatical knowledge or the ancient texts which were copied by the arabs and so on?

I know many of them were destroyed by the fanatics but come on they surely knew the earth was round right? Has anybody got any sources?

Starbo, Aristotle,Plato , Socrates many ancients knew the earth was round

About the Meteora, I do not know what the monks believe and don't care either, but the rock formations of the Meteora are not mentioned by any of the ancient geographers as far as I know (Strabo, Pausanias etc).

It's like they appeared in a night.