Carl Sagan explains how the Ancient Greek knew the earth was round

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[fatpoorvagrant]

It's amazing how ancient civilizations were smarter than modern day flat-earth youtubers.

[ProbablyCipher]

flat earthers: must have been the wind

[Joerideabike]

The rest of the story is equally important. The Greek scholar and his slave took off with a measuring chain and calculated the distance between the two points (about 800 miles ) and with the trigonometry known at that time calculated the size of the Earth, which was very close to Earth’s actual dimensions. There were some scholars of Columbus’s time that believed the earth was spherical but they were way off believing the Earth was about half what it really is.
Instead of sitting around the columns debating, these two hoofed it from point A to point B. People must have thought they were on a fool’s errand.

[glennmorgan]

He was so good at explaining simple facts to simple people. He is a great man, and he is missed 😢😊

[jfranks]

It’s amazing how he PROVED it too. He actually hired a group to count the distance as exactly as possible. Hundreds of miles. He used that information with cardinal directions to determine longitude and latitude; and the distance to the center of the earth. With this info he discovered the formula that showed the size of the earth and how to determine the time anywhere else.

[TheErockaustin]

Eratosthenes also calculated the Earth's circumference by measuring the difference in the two shadows, and was within the margin of error of the modern known measurement.

[MrSevillian]

The man that made me discover Science when I was an Elementary student. COSMOS was a gift to mankind.

[westpole]

Ancient flat earthers be like: "So you believe anything the Roman government tells you??"

[bradcarter]

Hopefuls: I bet we’ll have flying cars in the future!

Future scientists: FOR THE LAST TIME, THE EARTH IS ROUND

[SuperbiainProelioCitizen]

Flat Earthers: “the ancient Egyptians were being paid by the government”

[markbull]

Flat Earthers would say Ancient Greece was fake

[unums]

I’m glad someone found this gem.
Rest In Peace Carl Sagan.

[Edario]

Imagine being in ancient times you get called a round-earther instead of flat-earther

[sdluedtke]

Thank you Carl. You have been sincerely missed since your passing. Bless you always.😊

[decoyCoyote]

The indicator of a great understanding of a subject is the ability to teach it effectively to others.

[ianrawlings]

I grew up learning so much from Carl Sagan. His ability to convey complex physics in a way I could digest was truly special. He freed my mind!

[неостанавливаемый]

It's easier to fool someone than to convince them they've been fooled.

[gunjanbarman]

This man has brought Science better than most textbooks 😅

[Buchtaak]

I will also add, if anyone was wondering, that he saw both the shadows at the same time by looking at the shadow in one place in one year and then looking at the shadow in the other place at the same date the next year.

[BasileosHerodou]

I think the even more shocking thing is that people can't fathom communication being possible without a smartphone LMFAO