NationStates Jolt Archive

The world is round.

http://www.physlink.com/Education/AskExperts/ae535.cfm

Now that we have access to space, the easiest way to prove the Earth is spherical is to leave it and view it from a distance. Astronauts and space probes have done just that. Every picture of Earth ever taken shows only a circular shape, and the only geometric solid which looks like a circle from any direction is a sphere.

One of the oldest proofs of the Earth's shape, however, can be seen from the ground and occurs during every lunar eclipse. The geometry of a lunar eclipse has been known since ancient Greece. When a full Moon occurs in the plane of Earth's orbit, the Moon slowly moves through Earth's shadow. Every time that shadow is seen, its edge is round. Once again, the only solid that always projects a round shadow is a sphere.

... there's a horizon, meaning that the surface that one is observing from is not an infinite plane. On the clearest of days, the only restriction to one's range of sight is the horizon. There can be two explanations for this - one, that the Earth at some point just stops, as if you were looking off the edge of a table. The other is that the Earth is round. Hundreds of years ago, before the invention of the compass or sextant, precise navigation for ships was difficult, even with the stars. Ships that ventured past sight of land were often lost, and thus it was generally believed that the world simply *stopped* at the end of the horizon. With the invention of the compass, and improved map-making, people began to dare more, and with the return of Columbus from his trans-Atlantic voyage, the concept of the Earth as flat was shattered.

Further proof of the Earth being round came after the voyage of Columbus. When Newton discovered and measured the force of gravity, that number could then be tested anywhere the theory was known. Since the force of gravity is roughly the same everywhere on the globe, it could be surmised that the Earth must be spherical. If the Earth were not round, whole hemispheres would have different atmospheric pressure and significantly different sea levels. Also, pictures taken of the Earth in the last 50 years have proved absolutely conclusively that the Earth is round. These are just the arguments that don't require much physics knowledge to explain, there are others that are more technical, but I think that the simplest arguments are the best.

You can launch a rocket to a high altitude and take pictures of the earth (which various government agencies and private groups have already done thousands of times in the past), but that isn't the most practical way. Pictures and videos taken by orbiting satellites and space stations are certainly the most definitive proof that the earth is a sphere.

But if you're not convinced, read on...

You can also observe, with binoculars, ships slowly 'sinking' below the horizon as it sails farther and farther out to the ocean, then watch them come back. They certainly didn't fall off the edge of the earth! You can also sail or fly around the world.

The Greeks discovered that the earth is round by observing lunar eclipses (i.e. when the earth blocks the sun from the moon, casting its round shadow on the moon's surface).

Another method is simultaneously measuring the length of the shadows cast by identical poles perpendicular to a flat surface that is tangential to the earth's radius at various, distant locations. If indeed the earth is round, then the shadows should all vary in length from one distant location to another, which means that the angle at which the parallel rays of sunlight struck each pole varied from one location to another. (recall the alternate-angles theorem from Geometry class) If the earth is flat, then the lengths of all the shadows should be identical when measured simultaneously, since all rays of sunlight that strike the earth are parallel. However, they are not identical, but in fact, varies in such a way that the angles indicate a spherical surface. (This was one of the earliest methods to determine the radius of the earth)

Also, keep in mind the 24 hour time zones. When it is noon in Hawaii, it is approximately midnight in the Middle East and vice versa. How can it be noon and midnight simultaneously? It is certainly impossible with a flat earth and a sun millions of times more massive.

If I were a billionaire and physically fit, then proving to you the earth is round would be no problem. I can just take you with me on the space shuttle and we'll watch with our own eyes the earth from the orbiting International Space Station.


http://www.physlink.com/Education/AskExperts/Images/ae419a.jpg

Now you try and disagree with THAT!

Now you try and disagree with THAT!
http://www.flat-earth.org/
http://www.lhup.edu/~dsimanek/fe-scidi.htm
http://www.alaska.net/~clund/e_djublonskopf/FlatHome.htm

I'm a religious fundamentalist nutcase, I have no facts as usual, the world is flat dammit! :D

If Servus Dei were still here, he would probably disagree and burn you for heresy. A fundamentalist Catholic, he rejects anything that has come out of the Vatican since the Council of Trent (1563) as "heresy".

*gives up and looks for a pistol with a single bullet in it and a quiet, secluded location*

*gives up and looks for a pistol with a single bullet in it and a quiet, secluded location*
Won't find any... Gun Control you know...

Besides, the world is egg shaped... everyone knows that. It was laid by the cosmic Chicken.

I saw it when Oliver Wendal Jones and Milo Bloom went back in time to the beginning using the Stephen Hawking's method of self discovery.

All those photos are doctored.

The world is round.

...

Now you try and disagree with THAT!

Nonsense. It is oblate.

The Earth is not round - it is roundish.

The Earth is not round - it is roundish.

Sphericalish, shurely?

I'm a religious fundamentalist nutcase, I have no facts as usual, the world is flat dammit! :D

I'm a secular atheist, I have no master, I make my own rules. There is no God, simply because I want to do as I please!

I'm a secular atheist, I have no master, I make my own rules. There is no God, simply because I want to do as I please!
Me too!

Wait, you are religiously conservative. Is the threat of God's vengeance the only thing that keeps you from doing wrong?

Actually...historically speaking the educated of Columbus' day accepted the world as round. The issue of his voyage was not whether he would fall off the edge of the earth, but that it was too far for a ship to go the opposite direction. Rough calculations involving shadows and angles of stars in the sky at different locations in Europe had given them a rough estimate of the earth's dimensions. As such, they also knew the straight line distance between Europe and the East Indies. Knowing this they could arrive at a rough estimate of the distance going in the opposite direction...around the globe. Hence their belief it would be too far. They had no way of knowing there was something in the way (ie, the New World). In fact they were correct in their assumption it would be too far to go all the way around that way, as evidenced by the condition of Columbus' men and ships upon their arrival. Columbus believed the Earth was smaller than it actually was based upon a faulty calculation. Hence: They knew it was round (I'm not saying everyboy accepted it...but it's incorrect to characterize all Europeans as that ignorant.) and it was more of a debate of distance and the possibility of sailing that far without stopping.

Nonsense. It is oblate.
Very true.

Me too!

Wait, you are religiously conservative. Is the threat of God's vengeance the only thing that keeps you from doing wrong?

I'm not religiously conservative. I'm just religious. There is no "threat" of God's vengence. I don't do immoral things because the bible says they are immoral. I don't do wrong things because I believe they are wrong as well. AS In murder. Everyone knows that murder is wrong. If there is no God, the whole "moral compass" is a bullshit lie. I don't Murder. I don't steal. Not only because the bible says they are wrong, but because I know they are wrong, and don't want to infringe on the rights of others.

There is no "threat of God's vengeance". He forgives.

The world is actually a slight ellipsoid. It isn't perfectly spherical.

The world is actually a slight ellipsoid. It isn't perfectly spherical.
oblate is probably a better word. Ellipsoid implies that the earth is a flat oval.

"Nobody knows anything about the true shape of the world," he contends. "The known, inhabited world is flat. Just as a guess, I'd say that the dome of heaven is about 4,000 miles away, and the stars are about as far as San Francisco is from Boston."

BWAHAHAHAHAHAHAHAHAHAHAAHHAHAHAHAHAHA

http://www.lhup.edu/~dsimanek/fe-scidi.htm
This guy is great!

I'd just like to say that if the world was flat then there'd have been no way for the Japanese to attack Pearl Harbor the way they did.
Think about it.

I'd just like to say that if the world was flat then there'd have been no way for the Japanese to attack Pearl Harbor the way they did.
Think about it.

All of this round earth stuff is a cover up, the Japanese discovered the secrets of anti-matter based power and teleportation, and used that to warp their ships in behind U.S. defenses. Once General Patton led his team of Steam Powered 15-Foot Tall Mechanized Men in an assault against Iwo Jima (which was one of Japan's primary anti-matter research centers) he seized this technology for the use of the U.S. military. Since then the government has kept these devices secret and created the lie of a "round earth" to keep the people content.

All of this round earth stuff is a cover up, the Japanese discovered the secrets of anti-matter based power and teleportation, and used that to warp their ships in behind U.S. defenses. Once General Patton led his team of Steam Powered 15-Foot Tall Mechanized Men in an assault against Iwo Jima (which was one of Japan's primary anti-matter research centers) he seized this technology for the use of the U.S. military. Since then the government has kept these devices secret and created the lie of a "round earth" to keep the people content.

Well that blows my argument out the window. :D

Devil's Advocate time.

The world is round.

http://www.physlink.com/Education/AskExperts/ae535.cfm

Now that we have access to space, the easiest way to prove the Earth is spherical is to leave it and view it from a distance. Astronauts and space probes have done just that. Every picture of Earth ever taken shows only a circular shape, and the only geometric solid which looks like a circle from any direction is a sphere.

Every picture shown to me of ET reveals that aliens have visited this planet and made friends with excessively cute American kids. Heresay and pictures do not constitute evidence. They are easily faked.

One of the oldest proofs of the Earth's shape, however, can be seen from the ground and occurs during every lunar eclipse. The geometry of a lunar eclipse has been known since ancient Greece. When a full Moon occurs in the plane of Earth's orbit, the Moon slowly moves through Earth's shadow. Every time that shadow is seen, its edge is round. Once again, the only solid that always projects a round shadow is a sphere.
Or a flat disc that keeps the same orientation to the object on which the shadow is cast. No evidence here then.

... there's a horizon, meaning that the surface that one is observing from is not an infinite plane. On the clearest of days, the only restriction to one's range of sight is the horizon. There can be two explanations for this - one, that the Earth at some point just stops, as if you were looking off the edge of a table. The other is that the Earth is round. Hundreds of years ago, before the invention of the compass or sextant, precise navigation for ships was difficult, even with the stars. Ships that ventured past sight of land were often lost, and thus it was generally believed that the world simply *stopped* at the end of the horizon. With the invention of the compass, and improved map-making, people began to dare more, and with the return of Columbus from his trans-Atlantic voyage, the concept of the Earth as flat was shattered.

This makes the wonderful assumption, unjustified, that air does not affect our vision in any way. Air acts like a lens and the more air between the viewer and the object the smaller it appears until it becomes "invisible". There are more than two explanations. The true one and the two presented make three. There may be more.

Further proof of the Earth being round came after the voyage of Columbus. When Newton discovered and measured the force of gravity, that number could then be tested anywhere the theory was known. Since the force of gravity is roughly the same everywhere on the globe, it could be surmised that the Earth must be spherical. If the Earth were not round, whole hemispheres would have different atmospheric pressure and significantly different sea levels. Also, pictures taken of the Earth in the last 50 years have proved absolutely conclusively that the Earth is round. These are just the arguments that don't require much physics knowledge to explain, there are others that are more technical, but I think that the simplest arguments are the best.
The constancy of gravity across the disc is to be expected, after all it is turtles all the way down, and their mass is constant.

You can launch a rocket to a high altitude and take pictures of the earth (which various government agencies and private groups have already done thousands of times in the past), but that isn't the most practical way. Pictures and videos taken by orbiting satellites and space stations are certainly the most definitive proof that the earth is a sphere.
Pictures can be faked. See ET again.


You can also observe, with binoculars, ships slowly 'sinking' below the horizon as it sails farther and farther out to the ocean, then watch them come back. They certainly didn't fall off the edge of the earth! You can also sail or fly around the world.

The Greeks discovered that the earth is round by observing lunar eclipses (i.e. when the earth blocks the sun from the moon, casting its round shadow on the moon's surface).
Dealt with above. Repeating a false argument does not make it sound.

Another method is simultaneously measuring the length of the shadows cast by identical poles perpendicular to a flat surface that is tangential to the earth's radius at various, distant locations. If indeed the earth is round, then the shadows should all vary in length from one distant location to another, which means that the angle at which the parallel rays of sunlight struck each pole varied from one location to another. (recall the alternate-angles theorem from Geometry class) If the earth is flat, then the lengths of all the shadows should be identical when measured simultaneously, since all rays of sunlight that strike the earth are parallel. However, they are not identical, but in fact, varies in such a way that the angles indicate a spherical surface. (This was one of the earliest methods to determine the radius of the earth)
Remeber, o foolish one, that air acts as a lens. This distorts the path of the light, causing the shadows to vary at different distances from the sun. No proof here of the earth being round, just confirmation of the reason why ships disapear.

Also, keep in mind the 24 hour time zones. When it is noon in Hawaii, it is approximately midnight in the Middle East and vice versa. How can it be noon and midnight simultaneously? It is certainly impossible with a flat earth and a sun millions of times more massive.
The sun millions of times more massive? You jest knave, you jest. The sun is a smal ball of light that progresses across the sky. It only lights some areas at a time. Try shining a torch on a large flat surface from fairly nearby. There are regions of light and regions of dark. As the torch moves, so these regions move. Obvious when you think about it.

If I were a billionaire and physically fit, then proving to you the earth is round would be no problem. I can just take you with me on the space shuttle and we'll watch with our own eyes the earth from the orbiting International Space Station.
Start earning the money. I await this proof with interest.




Now you try and disagree with THAT!
I think I just did. :p

Well that blows my argument out the window. :D
There is no argument so sound that it can't be quashed by referencing General Patton and his legion fo 15-Foot Tall Steam Powered Mechanized Men

Maybe the earth appears spherical because our eyes are spherical?

The world is round, but we live inside a hollow earth, not on the outside.

The world is shaped like a donut, and we are doomed. The great cosmic Homer is coming!