Carl Sagan explains how the ancient Greeks knew the Earth was round and calculated its circumference over 2,000 years ago.
https://video.nostr.build/cc3c7af4bf2dd5343b6a5be87f5f1cf96d8941e63cd86a5cf200bea0116c1f0b.mp4
Discussion
βNah bro Earth is flat reeeeβ
LOL. I haven 't heard of this one before. I guess we should just give up on Euclidean geometry now.
wut?
What baffles me the most is how the heck they would have determined what was happening to an obelisk in Alexandria when they couldn't verify in real time. The strap an hourglass to a camel and hope the other guy started the hourglass at the same time?
This was my question too. How did they synch the clocks??
Itβs called knowing when noon was on the summer solstice when the sun was directly overhead (June 21). So at this time of day there was no shadow cast by the obelisk at Syrene. At the next summer solstice at noon you do the same thing at Alexandria, but this time a shadow is cast at 7 degrees. The rest is simple maths.
Correct. Time wasnβt super a factor as those 2 places are close enough in longitude.
There is a fascinating book about John Harrison called Longitude. Before we could tell time precisely longitude (at sea mainly) was SUPER difficult to determine. Worth a read.
The FE proponent of course says of the above that it just proves how close the sun is to the earth such that the light rays are not parallel.
Iβve given up trying to reason with them.
Carl Sagan fueled many of my childhood dreams. I preferred watching him a thousand times over watching cartoons. Still relevant even after so many years.