Flat earth? Please read the whole OP before responding...

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Flat earth? Please read the whole OP before responding...

Post #1

Post by tam »

Peace to you all,


Someone I know is considering the validity of the earth being flat. This person is considering a number of explanations being given by people who believe in a flat earth.

Some of the explanations I think I can handle, but on others, I do not know how to speak the 'science' well enough to be able to explain it so that another person can see if for themselves (and if no one wants to respond, I'm sure I can do the research myself). So just in case some of you have some great links you could post, or some great explanations that a layperson should be able to grasp, then that would be... well, great : )



Just facts and evidence please. No mocking comments even against the flat earth people. I would like to send this link to this person. Also, I think there was a suggestion on another thread somewhere on how a person could do an experiment themselves that would show them if the earth is flat or curved. But I do not recall what that experiment was.



So, some of the arguments this dear one is finding convincing are as follows:


1 - ships are not disappearing at the horizon due to the curvature of the earth; it is just that they are reaching the 'vanishing point' where we can no longer see them, because if we look through a powerful telescope, those ships are still visible. This is just a perspective issue.


2 - the photos supposedly taken from the moon or from space are recreations and not real photos, so they are photoshopped and not real. (the idea being that no one ever landed on the moon)


3 - the sun is what is moving (not the earth)


4 - If the earth is spinning at about 1600 km/hour, why do weather balloons move with the earth?


5 - Why are stars fixed points (the northern star, big dipper, etc,) if the earth is moving?


6 - How are vessels going into space not being crushed by the vacuum of space (since the metal is so thin on such vessels - like on the moon landing rover)?

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Re: Flat earth? Please read the whole OP before responding...

Post #2

Post by tam »

Peace to you all,

Can everyone see this thread? This was saved just as a draft before the update (I wasn't sure I wanted to post it and did not complete it) but it appears to have been automatically posted after the update.


thanks.

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Re: Flat earth? Please read the whole OP before responding...

Post #3

Post by Miles »

tam wrote: Thu Mar 12, 2020 4:10 pm Someone I know is considering the validity of the earth being flat. This person is considering a number of explanations being given by people who believe in a flat earth.

Some of the explanations I think I can handle, but on others, I do not know how to speak the 'science' well enough to be able to explain it so that another person can see if for themselves (and if no one wants to respond, I'm sure I can do the research myself). So just in case some of you have some great links you could post, or some great explanations that a layperson should be able to grasp, then that would be... well, great : )

Just facts and evidence please. No mocking comments even against the flat earth people. I would like to send this link to this person. Also, I think there was a suggestion on another thread somewhere on how a person could do an experiment themselves that would show them if the earth is flat or curved. But I do not recall what that experiment was.

So, some of the arguments this dear one is finding convincing are as follows:
1 - ships are not disappearing at the horizon due to the curvature of the earth; it is just that they are reaching the 'vanishing point' where we can no longer see them, because if we look through a powerful telescope, those ships are still visible. This is just a perspective issue.
2 - the photos supposedly taken from the moon or from space are recreations and not real photos, so they are photoshopped and not real. (the idea being that no one ever landed on the moon)
3 - the sun is what is moving (not the earth)
4 - If the earth is spinning at about 1600 km/hour, why do weather balloons move with the earth?
5 - Why are stars fixed points (the northern star, big dipper, etc,) if the earth is moving?
6 - How are vessels going into space not being crushed by the vacuum of space (since the metal is so thin on such vessels - like on the moon landing rover)?
Only because I'm absolutely bored.

1 - ships are not disappearing at the horizon due to the curvature of the earth; it is just that they are reaching the 'vanishing point' where we can no longer see them, because if we look through a powerful telescope, those ships are still visible. This is just a perspective issue.

..................................WRONG.




2 - the photos supposedly taken from the moon or from space are recreations and not real photos, so they are photoshopped and not real. (the idea being that no one ever landed on the moon)

Statements without evidence don't impress. Your evidence please.


3 - the sun is what is moving (not the earth)

Because geocentric orbits make much more sense. NOT!




4 - If the earth is spinning at about 1600 km/hour, why do weather balloons move with the earth?

Actually, it only spins at 1670 km/hr ( 1037 miles/hr) at the equator. At the poles its speed is zero. At 45 degree latitude (Minneapolis, Minn.) it's speed is 1180 km/hr. (733 miles/hr)

Because the earth' s atmosphere is gravitationally tied to the earth and is "pulled" along with the earth as it spins. And because weather balloons reside within our atmosphere they follow along.



5 - Why are stars fixed points (the northern star, big dipper, etc,) if the earth is moving?

They're not really fixed at all, but because they're so incredibly far away their movement is not discernible.




6 - How are vessels going into space not being crushed by the vacuum of space (since the metal is so thin on such vessels - like on the moon landing rover)?

What does this have to do with a flat earth? But to answer your question, because they're built to withstand it. The reinforced metal isn't "so thin."
Last edited by Miles on Thu Jul 09, 2020 6:37 pm, edited 1 time in total.

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Re: Flat earth? Please read the whole OP before responding...

Post #4

Post by Aetixintro »

Proper is probably to speak of an Earth flat enough for life on Earth while Earth is spherical on some level still.
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Re: Flat earth? Please read the whole OP before responding...

Post #5

Post by Difflugia »

tam wrote: Thu Mar 12, 2020 4:10 pm6 - How are vessels going into space not being crushed by the vacuum of space (since the metal is so thin on such vessels - like on the moon landing rover)?
Atmospheric pressure at sea level is about 15 psi, so that's what the inside of a spacecraft would be pressurized to. That's about the pressure of a fresh tennis ball (~12 psi over atmosphere). Carbonated cans of soda at room temperature are about 60 psi over atmosphere, or four times the pressure of a spacecraft.
tam wrote: Thu Mar 12, 2020 4:10 pmAlso, I think there was a suggestion on another thread somewhere on how a person could do an experiment themselves that would show them if the earth is flat or curved. But I do not recall what that experiment was.
I don't know if this is what you remember, but there was a relatively recent thread that included the apparently serious assertion that the Earth doesn't rotate. That's somewhat different than the Earth being flat, but most of the same arguments apply. If the Earth is a rotating sphere, then satellite orbits can be explained using relatively simple math. If it's not, then their behaviors are extremely complicated and weird.

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Re: Flat earth? Please read the whole OP before responding...

Post #6

Post by Miles »

Image



Occam's Razor!

.

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Re: Flat earth? Please read the whole OP before responding...

Post #7

Post by DrNoGods »

[Replying to tam in post #1]
1 - ships are not disappearing at the horizon due to the curvature of the earth; it is just that they are reaching the 'vanishing point' where we can no longer see them, because if we look through a powerful telescope, those ships are still visible. This is just a perspective issue.

2 - the photos supposedly taken from the moon or from space are recreations and not real photos, so they are photoshopped and not real. (the idea being that no one ever landed on the moon)

3 - the sun is what is moving (not the earth)

4 - If the earth is spinning at about 1600 km/hour, why do weather balloons move with the earth?

5 - Why are stars fixed points (the northern star, big dipper, etc,) if the earth is moving?

6 - How are vessels going into space not being crushed by the vacuum of space (since the metal is so thin on such vessels - like on the moon landing rover)?
Way too late to respond, but I just saw this today and can't help but add some comments although the others are correct of course. But in order:

1) This is a common flat earther belief, but is wrong. Perspective is indeed a cause of something appearing smaller at greater distances, and this is independent of the shape of the earth. The angular resolution of the human eye (the smallest thing that can be seen) is determined by the Rayleigh criterion. For a 5 mm wide pupil and at 550 nm wavelength (green), humans with 20/20 vision can see something that is about 0.02 degrees (tall or wide) within their field of view. When something is so far away that it occupies less than this angle you cannot see it. In that case a telescope would bring it back into view as it magnifies the object and effectively increases the size to above 0.02 degrees.

However, this is completely different from having something disappear over the horizon like a ship. When that happens, a telescope will NOT bring it back into view if the person is viewing from the same height above the ground as with the naked eye. There are "earth curve calculators" on the web that allow you to enter your height above the ground, the distance to an object, and the object's height, and it will calculate (based on the known radius of the earth and a simple formula) how much of the bottom of that object would be hidden by the earth's curvature. This much will be hidden no matter if you're looking with the naked eye, or a telescope, and this is easily proven. Note that refraction can cause less of the object to be hidden and must also be taken into account, and this can vary widely depending on temperature and things like temperature inversions. Google "Fata Morgana" for some interesting optical effects caused by refraction (ships can appear to be positioned above the water, for example). Refraction must be considered for more accurate numbers, but earth's curvature is easily proven by many methods.

2) Complete nonsense. Flat earthers have to make this claim because the many thousands of photos and videos provided by NASA, private space companies (eg. SpaceX), and the space agencies of many other countries prove beyond any doubt that the earth is an oblate spheroid and it rotates. If they accepted these images and videos as real then their entire premise is destroyed. But what the flat earthers can't seem to describe is what benefit there would be to any government to spend hundreds of billions of dollars over decades on the biggest hoax ever perpetrated on humans. It makes no sense, and of course is not true.

3) This is also nonsense as the orbital mechanics and physics of our solar system only work if the planets are orbiting the central star (the sun). Flat earthers claim that the sun and the moon are the same size, and only hundreds or thousands of miles above the earth. Both are completely wrong and this is just another nonsensical claim they use to try and make their flat earth models work. Some of these people even claim that the moon isn't real, and that it doesn't reflect light from the sun but emits its own "cold" light. Utter nonsense.

4) Already answered ... the atmosphere (and oceans) are gravitaionally bound to the earth and move with it. Otherwise the wind would be blowing 1000 MPH when you walked outside. Since flat earthers claim the earth is stationary and does not rotate, and they claim that gravity does not exist (! ... another thing they have to do or their model falls apart immediately), they come up with things like this to try and justify a stationary earth.

5) Already answered ... the great distance to stars. Even the closest star to earth is 4.2 light years away, which is about 25 trillion miles (you could fit about 30 million suns between earth and the closest star to our solar system). Also, the earth's rotation axis precesses (axial precession) with a period of about 26,000 years. So the north star does "wobble" a bit in its location but the period is so long compared to a human life we don't notice it.

6) Already answered ... even a soda can can handle 15 PSI of pressure difference, which is the maximum difference in pressure between ground level on earth and space. This question is silly, but all flat earth ideas are silly and easily disproven.

These people are mostly consipiracy theorists who don't trust governments and like to be part of a group who goes against "the man." I expect that if the earth were flat, all of these people would be "ballers" (or globetards, globers, and other names they use) because it is the opposite side. The earth isn't flat, and I expect most of them really know that but some have figured out how to make a buck from it (books, YouTube channels). And, there are no doubt some who are just scientifically illiterate so they do fall for it due to ignorance of science and simple math.
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Re: Flat earth? Please read the whole OP before responding...

Post #8

Post by Sherlock Holmes »

[Replying to tam in post #1]

Well any continuous curved 2D surface is flat if we confine our attention to a sufficiently small region. This is why we are able to use Pythagoras's theorem when laying out plans for buildings and so on. So if the earth is not flat how can Pythagoras's theorem be used without any problems? In non-Euclidean geometry Pythagoras's theorem is the scientific way we test for flatness, this was elaborated by Gauss - see "Gaussian Curvature".

On a truly curved surface Pythagoras does not hold, a more complex metric must be used.

So it is not wrong to say "the earth is flat" if a test (Pythagoras) proves that it is, at least in a sufficiently small region.

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Re: Flat earth? Please read the whole OP before responding...

Post #9

Post by The Barbarian »

To add to this:

The Coriolis effect makes no sense, absent a spinning globe. The clockwise/counterclockwise thing, you know.

You can launch larger payloads into orbit by launching eastward because you add the Earth's rotational speed to the rocket, much like throwing an object from a moving vehicle. And because rotational velocity depends on the latitude, you can launch larger payloads the closer you get to the equator.

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Re: Flat earth? Please read the whole OP before responding...

Post #10

Post by The Barbarian »

Sherlock Holmes wrote: Sun May 15, 2022 2:12 pm [Replying to tam in post #1]

On a truly curved surface Pythagoras does not hold, a more complex metric must be used.
Non-Euclidian geometry works pretty much like you'd expect. The size of the globe and the size of a triangle inscribed on it, will determine the sum of the degrees of the three interior angles. For distances that are a very small percent of the size of the globe, sum of the angles approaches 180 degrees as a lower limit.

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