# The Earth is flat ... ish?

• 29 Replies
• 1980 Views

#### Curiouser and Curiouser

• 1661
##### The Earth is flat ... ish?
« on: February 12, 2018, 09:06:18 AM »
In trying to determine earth curvature / non-curvature by means of looking at objects at distance over water (ship masts, Chicago skyline, bridge supports, etc.) all that is being done, or not done, is looking at the geometry in a very small localized area. A proof of curvature or non-curvature over an infinitessimal fraction of the earth does not prove or disprove a globe or non-globe.

A proof would be to measure amount and direction of localized curvature at one location and proceed with a network of bootstrapped subsequent points until a full globe or shown or not shown. Cherry-picking a tiny handful of points is insufficient.

So why is this attempted "proof" so ubiquitous? Why try to prove a thing that does not -- cannot -- lead to a proof of the big picture?

?

#### smokified

• 386
##### Re: The Earth is flat ... ish?
« Reply #1 on: February 12, 2018, 04:15:14 PM »
In trying to determine earth curvature / non-curvature by means of looking at objects at distance over water (ship masts, Chicago skyline, bridge supports, etc.) all that is being done, or not done, is looking at the geometry in a very small localized area. A proof of curvature or non-curvature over an infinitessimal fraction of the earth does not prove or disprove a globe or non-globe.

A proof would be to measure amount and direction of localized curvature at one location and proceed with a network of bootstrapped subsequent points until a full globe or shown or not shown. Cherry-picking a tiny handful of points is insufficient.

So why is this attempted "proof" so ubiquitous? Why try to prove a thing that does not -- cannot -- lead to a proof of the big picture?

Uhmm...this has already been done a long time ago.

"Suppose that the earth is a sphere of radius 3963 miles. If you are at a point P on the earth's surface and move tangent to the surface a distance of 1 mile then you can form a right angled triangel as in the diagram. Using the theorem of Pythagoras a2 = 39632 + 12 = 15705370 and thus a = 3963.000126 miles. Thus your position is 3963.000126 - 3963 = 0.000126 miles above the surface of the earth. 0.000126 miles = 12*5280*0.000126 = 7.98 inches. Hence the earth's surface curves approximately 8 inches in one mile."

(http://mathcentral.uregina.ca/qq/database/qq.09.97/dyck2.html)

This is not something that is up for debate.  This is just the way it is.

?

#### robintex

• Ranters
• 5322
##### Re: The Earth is flat ... ish?
« Reply #2 on: February 12, 2018, 07:05:32 PM »
Of course the earth is flat.
Have you ever heard of The Bonneville Salt Flats ?
I have never heard of The Bonneville Salt Curves !
Stick close , very close , to your P.C.and never go to sea
And you all may be Rulers of The Flat Earth Society

Look out your window , see what you shall see
And you all may be Rulers of The Flat Earth Society

Chorus:
Yes ! Never, never, never,  ever go to sea !

?

#### ISMeister

• 11
##### Re: The Earth is flat ... ish?
« Reply #3 on: February 12, 2018, 08:54:19 PM »
Of course the earth is flat.
Have you ever heard of The Bonneville Salt Flats ?
I have never heard of The Bonneville Salt Curves !

This is the best spot to prove earths curvature. Just have 2 sets of laser level perpendicular to earth at diff heights and find the distances between poles at the diff. heights . it should be different.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #4 on: February 12, 2018, 10:49:00 PM »
Uhmm...this has already been done a long time ago.

[snip]

This is not something that is up for debate.  This is just the way it is.
No, this is not something that has already been done a long time ago.

The issue is that any single measurement of curvature only does so in one location and is valid for a small region. (The area around Chicago, the area around Lake Ponchartrain, etc., etc.) Each of these is a small localized measurement. You may wish to hypothesize that the supposed measured curvature is the same everywhere, and therefore proves a globe, but using only the given measurement that's not a proof -- it's a conjecture. Proving a particular curvature at Point A, Point B, and Point C only proves the local curvature at those spots ... unless Point B is in sight of Point A, Point C is in sight of Point B, etc. and you show by rigorous chain of linked measurements that you can map out sufficient area to determine shape.

Since no attempt has ever been made to do this, why do people continue to try to pose the "proof" "I have made this curvature measurement of a local area which then proves the Earth is a sphere"? They have made a measurement, then assumed the Earth is a sphere, then said "This proves the Earth is a sphere."

It is poor proofsmanship.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #5 on: February 12, 2018, 10:57:57 PM »
Of course the earth is flat.
Have you ever heard of The Bonneville Salt Flats ?
I have never heard of The Bonneville Salt Curves !

This is the best spot to prove earths curvature. Just have 2 sets of laser level perpendicular to earth at diff heights and find the distances between poles at the diff. heights . it should be different.
Another thought experiment by someone who has never used a laser to make a precision angular measurement, much less a laser level.

There are ways of doing this, but not with lasers.

#### Macarios

• 2076
##### Re: The Earth is flat ... ish?
« Reply #6 on: February 13, 2018, 03:48:55 AM »
Of course the earth is flat.
Have you ever heard of The Bonneville Salt Flats ?
I have never heard of The Bonneville Salt Curves !

This is the best spot to prove earths curvature. Just have 2 sets of laser level perpendicular to earth at diff heights and find the distances between poles at the diff. heights . it should be different.

If precisely vertical laser beams are 1852 meters apart their tilt is one arc minute.
Do you think just the beam divergence could be more than that?
In perfectly clear air it s not easy to see thin laser beam.
In slightly dusty / foggy air it is not easy to see laser beam from far enough.

THERE IS a way to do it even without lasers, and you don't need perfectly flat ground.
Verticals keep their direction regardless the altitude.
Verticals keep tilting away from each other more with increase of their relative distance.
I don't have to fight about anything.
These things are not about me.
When one points facts out, they speak for themselves.
The main goal in all that is simplicity.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #7 on: February 13, 2018, 07:04:00 AM »
This is the best spot to prove earths curvature. Just have 2 sets of laser level perpendicular to earth at diff heights and find the distances between poles at the diff. heights . it should be different.

If precisely vertical laser beams are 1852 meters apart their tilt is one arc minute.
Do you think just the beam divergence could be more than that?
In perfectly clear air it s not easy to see thin laser beam.
In slightly dusty / foggy air it is not easy to see laser beam from far enough.
The divergence of a laser beam depends on diameter and wavelength.
The above poster was contemplating horizontal beams and their varying heights at distance. The poster thinks that looking at height of beam on stick at distance will show sufficient difference to show curvature. It won't.
Making a beam "perfectly" horizontal or vertical to the desired degree of accuracy requires much more care than thought experimenters imagine.
This is not the "experiment" of using two vertical laser beams and trying to spot the angle between the. That has already been discussed and the problems raised.
THERE IS a way to do it even without lasers, and you don't need perfectly flat ground.
Verticals keep their direction regardless the altitude.
Verticals keep tilting away from each other more with increase of their relative distance.
I am well aware of the methods used for precision surveying, and use instruments that are quite a bit more precise than a \$30 sextant.

A sextant measurement, however, relies on different assumptions than the geometry of earth level at two different places (a la laser beams at Bonneville). A sextant assumes that the objects being measured are (essentially) an infinite distance away. Almost all FE theory states that Sun, Moon, and stars are much closer. Therefore a sextant measurement "proving" a round Earth by means of an artificial horizon has done so using an assumption (far astronomical objects) that most FE already reject.

#### Macarios

• 2076
##### Re: The Earth is flat ... ish?
« Reply #8 on: February 13, 2018, 07:31:01 AM »
I am well aware of the methods used for precision surveying, and use instruments that are quite a bit more precise than a \$30 sextant.

You do, and you either can afford them (say, theodolites), or have access through work or through people you know.
Not everyone does. \$30 sextant is enough for lot of things, such as lunar paralax (measuring angle between Moon and selected star at Moon's path).
Cheapest sextant still has resolution of 0.2 arcminute, some have 0.1, and lunar paralax measured with time window of 2 hours from 45 degrees north is 21 arcminute.

A sextant measurement, however, relies on different assumptions than the geometry of earth level at two different places (a la laser beams at Bonneville). A sextant assumes that the objects being measured are (essentially) an infinite distance away. Almost all FE theory states that Sun, Moon, and stars are much closer. Therefore a sextant measurement "proving" a round Earth by means of an artificial horizon has done so using an assumption (far astronomical objects) that most FE already reject.

Sextant measurement can show that measurement using Polaris on globe doesn't depend on latitude and on flat does.
At 30 degrees north you will measure 1.4 arcminutes, at 45 degrees 1.0 and at 60 degrees 0.6.
On gobe at all latitudes it will be 1 arcminute.

I wish I myself still have access to some good theodolite, but it was long time ago, when I had no idea that anyone could really believe in Flat Earth.
I don't have to fight about anything.
These things are not about me.
When one points facts out, they speak for themselves.
The main goal in all that is simplicity.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #9 on: February 13, 2018, 09:03:01 AM »
Sextant measurement can show that measurement using Polaris on globe doesn't depend on latitude and on flat does.
At 30 degrees north you will measure 1.4 arcminutes, at 45 degrees 1.0 and at 60 degrees 0.6.
On gobe at all latitudes it will be 1 arcminute.

To "show" what you state above requires some assumptions about astronomical objects.

Please "show" and then show all work, including assumptions.

I think you'll find that you run into the problem that you're begging the question. You'll be trying to prove something, and one of the assumptions used in your proof is what you're trying to prove (or at least a FE frequently-disputed assumption).

?

#### smokified

• 386
##### Re: The Earth is flat ... ish?
« Reply #10 on: February 13, 2018, 09:23:25 AM »
Uhmm...this has already been done a long time ago.

[snip]

This is not something that is up for debate.  This is just the way it is.
No, this is not something that has already been done a long time ago.

The issue is that any single measurement of curvature only does so in one location and is valid for a small region. (The area around Chicago, the area around Lake Ponchartrain, etc., etc.) Each of these is a small localized measurement. You may wish to hypothesize that the supposed measured curvature is the same everywhere, and therefore proves a globe, but using only the given measurement that's not a proof -- it's a conjecture. Proving a particular curvature at Point A, Point B, and Point C only proves the local curvature at those spots ... unless Point B is in sight of Point A, Point C is in sight of Point B, etc. and you show by rigorous chain of linked measurements that you can map out sufficient area to determine shape.

Since no attempt has ever been made to do this, why do people continue to try to pose the "proof" "I have made this curvature measurement of a local area which then proves the Earth is a sphere"? They have made a measurement, then assumed the Earth is a sphere, then said "This proves the Earth is a sphere."

It is poor proofsmanship.

No...we literally have the whole earth measured, mapped and cataloged.  You can verify any of these measurements any time you want.  You just refuse to accept the information as fact because it destroys the delusion of a flat earth and forces you to admit that we are actually not being lied to.

?

#### robintex

• Ranters
• 5322
##### Re: The Earth is flat ... ish?
« Reply #11 on: February 13, 2018, 10:01:57 AM »
The simplest way to observe the curvature of the earth is by observing the distance to the horizon.
You could do this by these methods :
(1) Standing on a beach on the shore on the ocean, the higher you are, the farther you can see to the horizon.
(2) On a ship at sea, the higher you are on a deck on the ship, the farther you can see to the horizon.

There is really no question that there is curvature to the earth.
There is really no question that the earth is a globe.
There is really no question that the earth is not some flat disc surrounded by a wall of ice around the edge, with a dome of ice overhead.
One flat earth notion is that you would never see the horizon on a flat earth.
You would just see "An indistinct blur which fades away at an indfefinite distance."
« Last Edit: February 13, 2018, 10:13:16 AM by Googleotomy »
Stick close , very close , to your P.C.and never go to sea
And you all may be Rulers of The Flat Earth Society

Look out your window , see what you shall see
And you all may be Rulers of The Flat Earth Society

Chorus:
Yes ! Never, never, never,  ever go to sea !

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #12 on: February 13, 2018, 10:08:36 AM »
No...we literally have the whole earth measured, mapped and cataloged.  You can verify any of these measurements any time you want.  You just refuse to accept the information as fact because it destroys the delusion of a flat earth and forces you to admit that we are actually not being lied to.
Your preconceived notions are forcing you into an argument that is quite different from the original proposition.

The whole earth is not mapped and catalogued using the method described in the OP. Is it?

With no other information, the "proof" that the Earth is round or flat (using only the limited measurements that people make using the technique described in the OP) is an insufficient proof because there are not enough data points. The question posed was why do people use this technique to prove or disprove, when the method given is incapable of proving or disproving?

we literally have the whole earth measured, mapped and cataloged.  You can verify any of these measurements any time you want.
The accumulation of other data is irrelevant to the question asked.
You just refuse to accept the information as fact because it destroys the delusion of a flat earth and forces you to admit that we are actually not being lied to.
You make quite a few assumptions there. It seems as if you just want to argue your position, rather than address the question asked. Would it surprise you to know how wrong you are?

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #13 on: February 13, 2018, 10:15:20 AM »
The simplest way to observe the curvature of the earth is by observing the distance to the horizon.
You could do this by these methods :
(1) Standing on a beach on the shore on the ocean, the higher you are, the farther you can see to the horizon.
(2) On a ship at sea, the higher you are on a deck on the ship, the farther you can see to the horizon.
Yes.

You are right.

The issue is that you have determined (or not) a curvature valid for a small, limited, localized region (the region that you can see).

Extrapolating that curvature (call it 50 miles, I'll be generous) to an entire globe of 25,000 miles circumference is a conjecture, but it is not a proof. If you go out to sea 50 miles and do it again, and then again, and then again, and then again, and then again (500 times) to get one circle --- and then do it in different directions 500 times --- that begins to approach a proof.

A handful of discrete observations does not.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #14 on: February 13, 2018, 10:26:58 AM »
The ask in the first post seems to make mad those who want to fight the view of Round Earth or Flat Earth. So I make the ask plain with use of words that each have one sole sound part.

Here is a proof folks use a lot. The proof is for a small place. Earth is a large place. As such, the proof is not a good proof. It is a poor proof for what the folks want to prove.

Why do folks use a bad proof if the proof is not what folks need to prove a thing?

#### Macarios

• 2076
##### Re: The Earth is flat ... ish?
« Reply #15 on: February 13, 2018, 10:28:30 AM »
Sextant measurement can show that measurement using Polaris on globe doesn't depend on latitude and on flat does.
At 30 degrees north you will measure 1.4 arcminutes, at 45 degrees 1.0 and at 60 degrees 0.6.
On gobe at all latitudes it will be 1 arcminute.

To "show" what you state above requires some assumptions about astronomical objects.

Please "show" and then show all work, including assumptions.

I think you'll find that you run into the problem that you're begging the question. You'll be trying to prove something, and one of the assumptions used in your proof is what you're trying to prove (or at least a FE frequently-disputed assumption).

If you go to 60 degrees north in Flat model, Polaris is 3300 miles above the ground, and you will see it at angle of 56.5 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 1.25 arcminutes.
If you go to 45 degrees north in Flat model, Polaris is 3300 miles above the ground, and you will see it at angle of 46 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 1.0 arcminutes.
If you go to 30 degrees north in Flat model, Polaris is 3300 miles above the ground, and you will see it at angle of 37.7 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 0.85 arcminutes.

If you go to 60 degrees north in Globe model, Polaris is 434 light years above the ground, and you will see it at angle of 60 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 1.0 arcminutes.
If you go to 45 degrees north in Globe model, Polaris is 434 light years above the ground, and you will see it at angle of 45 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 1.0 arcminutes.
If you go to 30 degrees north in Globe model, Polaris is 434 light years above the ground, and you will see it at angle of 30 degrees.
Using Polaris to measure tilt between two verticals at ends of north-south segment 1852 meters long you will get 1.0 arcminutes.

We know, and it is easy to find, that nautical mile was defined as 1852 meters because
everywhere in the world tilt between two verticals at opposite ends of one nautical mile is
1.0 arcminute. It was good and easy way for navigators (and others) to convert degrees into distances.
For example, measured angle of 3 degrees 17 minutes is 3 * 60 + 17 = 197 nautical miles.

In Flat Earth model it doesn't work as seen above.
One nautical mile wouldn't have measuring value as it would change with degrees of position.

--------------------------------

Now, this example, no matter how obvious, will be rejected by Flat Earthers not because "there could be errors".
Flat Earthers will either know that there are no errors here, or they know too little to know what is this all about.
This will be rejected because it doesn't say what they want to hear.
Majority of Flat Earthers will mostly disregard the whole process.
Maybe some of them will try to throw in some additional "facts" to "water down" the obvious part and draw attention somewhere else.
Several notorious Flat Earthers already reject facts an figures, no matter what they are.

But at least others, who aren't sure, will not fall into trap of Flat Earth deception.
If they measure by themselves using relatively affordable sextant, Flat Earthers will not be able to tell them "somebody 'indictrinated' you".
Just like nobody can tell me "Moon is 3000 miles up", because I measured it myself, using two different methods.
« Last Edit: February 13, 2018, 10:36:27 AM by Macarios »
I don't have to fight about anything.
These things are not about me.
When one points facts out, they speak for themselves.
The main goal in all that is simplicity.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #16 on: February 13, 2018, 10:41:17 AM »
Sextant measurement can show that measurement using Polaris on globe doesn't depend on latitude and on flat does.
At 30 degrees north you will measure 1.4 arcminutes, at 45 degrees 1.0 and at 60 degrees 0.6.
On gobe at all latitudes it will be 1 arcminute.

To "show" what you state above requires some assumptions about astronomical objects.

Please "show" and then show all work, including assumptions.

I think you'll find that you run into the problem that you're begging the question. You'll be trying to prove something, and one of the assumptions used in your proof is what you're trying to prove (or at least a FE frequently-disputed assumption).

If you go to 60 degrees north in Flat model, "Polaris is 3300 miles above the ground", [snip]
Gee. There's an interesting assumption. Maybe you read it somewhere.

I certainly don't subscribe to that assumption.

And anyway, you're pointing the conversation further and further afield from the original question which has to do with a particular method of measuring Earth curvature, and why that particular method is a bad method. And yet people continue to use this bad method as a proof. Introducing a different method is not relevant to the original question. Thanks for participating, but I'd prefer if you kept on-topic.
« Last Edit: February 13, 2018, 10:45:20 AM by Curiouser and Curiouser »

#### Macarios

• 2076
##### Re: The Earth is flat ... ish?
« Reply #17 on: February 13, 2018, 10:53:29 AM »
Sextant measurement can show that measurement using Polaris on globe doesn't depend on latitude and on flat does.
At 30 degrees north you will measure 1.4 arcminutes, at 45 degrees 1.0 and at 60 degrees 0.6.
On gobe at all latitudes it will be 1 arcminute.

To "show" what you state above requires some assumptions about astronomical objects.

Please "show" and then show all work, including assumptions.

I think you'll find that you run into the problem that you're begging the question. You'll be trying to prove something, and one of the assumptions used in your proof is what you're trying to prove (or at least a FE frequently-disputed assumption).

If you go to 60 degrees north in Flat model, "Polaris is 3300 miles above the ground", [snip]
Gee. There's an interesting assumption. Maybe you read it somewhere.

I certainly don't subscribe to that assumption.

And anyway, you're pointing the conversation further and further afield from the original question which has to do with a particular method of measuring Earth curvature, and why that particular method is a bad method. And yet people continue to use this bad method as a proof. Introducing a different method is not relevant to the original question. Thanks for participating, but I'd prefer if you kept on-topic.

Most common Flat Earth model (you will recognize it by Gleason map), claims Sun and Moon are 5005 km high (3110 miles), and Dome is right above.
Polaris is in the center of the Dome and that's why it doesn't move with Dome rotation.
If you assume higher Polaris, you get even worse results.
This way at least angular altitudes of Polaris are closest to values measured in real life.

Lower can't support the Dome existence, simply because of Sun, higher would ruin Flat Earth approximations.

Try with other altitudes of Polaris and see for yourself.
Be inquisitive. :-)
You said you use more accurate devices than sextant.
It shows that you understand geometry well.

When I get back I might describe better stuff, but my previous example did include wider area, all the way between 30 and 60 degrees of latitude.
Measuring big series of small segments could be bad, or not, depending on error handling.

Meanwhile maybe measurements of the whole tropical belt would be wide enough for you?
Like this: https://www.theflatearthsociety.org/forum/index.php?topic=73974.msg2012800#msg2012800.
« Last Edit: February 13, 2018, 11:26:37 AM by Macarios »
I don't have to fight about anything.
These things are not about me.
When one points facts out, they speak for themselves.
The main goal in all that is simplicity.

?

#### robintex

• Ranters
• 5322
##### Re: The Earth is flat ... ish?
« Reply #18 on: February 13, 2018, 11:07:22 AM »
The simplest way to observe the curvature of the earth is by observing the distance to the horizon.
You could do this by these methods :
(1) Standing on a beach on the shore on the ocean, the higher you are, the farther you can see to the horizon.
(2) On a ship at sea, the higher you are on a deck on the ship, the farther you can see to the horizon.
Yes.

You are right.

The issue is that you have determined (or not) a curvature valid for a small, limited, localized region (the region that you can see).

Extrapolating that curvature (call it 50 miles, I'll be generous) to an entire globe of 25,000 miles circumference is a conjecture, but it is not a proof. If you go out to sea 50 miles and do it again, and then again, and then again, and then again, and then again (500 times) to get one circle --- and then do it in different directions 500 times --- that begins to approach a proof.

A handful of discrete observations does not.

If you are going from the West Coast of the USA to Japan, that is what you are continually doing....And the distance to the horizon is always the same no matter where you are on that ship or where you are on the ocean. Been there; done that many times.

Lots of people seem to get exasperated about all this talk about some people actually believing the earth is flat.
But I have come  to the conclusion that it's all a bunch of foolishness and this website (and that "other one") are just two more  "spoof" websites on the Internet and just sit back in my armchair and enjoy the entertainment for the laughs you get from some of the fllat earth stuff you read on these forums. LOL.
Cheers !
« Last Edit: February 13, 2018, 11:51:20 AM by Googleotomy »
Stick close , very close , to your P.C.and never go to sea
And you all may be Rulers of The Flat Earth Society

Look out your window , see what you shall see
And you all may be Rulers of The Flat Earth Society

Chorus:
Yes ! Never, never, never,  ever go to sea !

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #19 on: February 13, 2018, 11:25:58 AM »
If you are going from the West Coast of the USA to Japan, that is what you are continually doing and the distance to the horizon is always the same no matter where you are on that ship on the ocean. Been there; done that many times.
Small quibble, was originally talking about measuring curvature by looking at known height of objects over the horizon and their apparent "lowering." Distance to horizon a different measurement, but I'll give it to you.

Really? You've measured the distance to the horizon on a ship every 50 miles from the West Coast of the USA to Japan? Every 50 miles? Day and night? Many times? That's pretty good!

Too bad that's less than 1/4 of a globe. Funny thing about proofs, you have to be kind of rigorous.

?

#### robintex

• Ranters
• 5322
##### Re: The Earth is flat ... ish?
« Reply #20 on: February 13, 2018, 12:10:10 PM »
If you are going from the West Coast of the USA to Japan, that is what you are continually doing and the distance to the horizon is always the same no matter where you are on that ship on the ocean. Been there; done that many times.
Small quibble, was originally talking about measuring curvature by looking at known height of objects over the horizon and their apparent "lowering." Distance to horizon a different measurement, but I'll give it to you.

Really? You've measured the distance to the horizon on a ship every 50 miles from the West Coast of the USA to Japan? Every 50 miles? Day and night? Many times? That's pretty good!

Too bad that's less than 1/4 of a globe. Funny thing about proofs, you have to be kind of rigorous.

I haven't done it "every 50 miles".
But when I was in the USN I have done it several times by observing ships on the horizon or those just this side of the horizon.
My assignment was as a radar technician and I checked the distance to those ships on the radar. (Range and Bearing)
They coincided with the old fomula : "The approximate  distance to the horizon (in miles) is equal to 1.2 (a constant) times the square root of the height of the observer above sea level (in feet.)"
Actually I understand this was part of a lookout's training. Estimate the distance and compare it with radar ranges and bearings.

I was never an official or certified lookout in the USN. But you might check with some of them who have made "Round The World Cruises" which are more than "less than  1/4 of a globe" if that wasn't enough.

If you were a lookout in the crow's nest, let us say 100 feet above sea level, the horizon would  always appoximately appear to be about 12.2 miles from you. On the bridge, say 65 feet above sea level, approximately 9.6 mies. On the main deck , 50 feet above sea level, about 8.5 miles.If you want to dispute these figures go tell it to an old Chief Quartermaster in the Navy. They don't have crow's nest anymore  though.On a boat at sea level , about 2 or 3 miles.And.....Oh Yes !.....Ask them if they can "restore a ship to full sight once it has passed out of sight over and beyond the horizon by looking at it with a telescope (or binoculars) " ?

Sorry......I just like to harass flat earthers with round earth facts......a big LOL to that !

« Last Edit: February 13, 2018, 01:46:32 PM by Googleotomy »
Stick close , very close , to your P.C.and never go to sea
And you all may be Rulers of The Flat Earth Society

Look out your window , see what you shall see
And you all may be Rulers of The Flat Earth Society

Chorus:
Yes ! Never, never, never,  ever go to sea !

#### rabinoz

• 26528
• Real Earth Believer
##### Re: The Earth is flat ... ish?
« Reply #21 on: February 13, 2018, 02:31:31 PM »
If you are going from the West Coast of the USA to Japan, that is what you are continually doing and the distance to the horizon is always the same no matter where you are on that ship on the ocean. Been there; done that many times.
Small quibble, was originally talking about measuring curvature by looking at known height of objects over the horizon and their apparent "lowering." Distance to horizon a different measurement, but I'll give it to you.

Really? You've measured the distance to the horizon on a ship every 50 miles from the West Coast of the USA to Japan? Every 50 miles? Day and night? Many times? That's pretty good!

Too bad that's less than 1/4 of a globe. Funny thing about proofs, you have to be kind of rigorous.
I thought it was only flat-earthers that presented irrefutable proofs about the shape of the earth, only to have their irrefutable proof refuted in 2 minutes.

Scientists prefer to accumulate sufficient evidence that supports a hypothesis to make that hypothesis into an accepted theory.

So if we find that this "distance to the horizon is always the same no matter where you are on that ship on the ocean"
then you may not have proved that the earth is a sphere but
you certainly have overwhelming evidence that the earth is not flat.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #22 on: February 13, 2018, 03:34:25 PM »

I thought it was only flat-earthers that presented irrefutable proofs about the shape of the earth, only to have their irrefutable proof refuted in 2 minutes.

Scientists prefer to accumulate sufficient evidence that supports a hypothesis to make that hypothesis into an accepted theory.

So if we find that this "distance to the horizon is always the same no matter where you are on that ship on the ocean"
then you may not have proved that the earth is a sphere but
you certainly have overwhelming evidence that the earth is not flat.

Somebody gets it.

?

#### ER22

• 393
##### Re: The Earth is flat ... ish?
« Reply #23 on: February 13, 2018, 04:51:13 PM »
In trying to determine earth curvature / non-curvature by means of looking at objects at distance over water (ship masts, Chicago skyline, bridge supports, etc.) all that is being done, or not done, is looking at the geometry in a very small localized area. A proof of curvature or non-curvature over an infinitessimal fraction of the earth does not prove or disprove a globe or non-globe.

Then why do ships disappear over if not the horizon?

A proof would be to measure amount and direction of localized curvature at one location and proceed with a network of bootstrapped subsequent points until a full globe or shown or not shown. Cherry-picking a tiny handful of points is insufficient.

So, pretty much like cell phone towers.

So why is this attempted "proof" so ubiquitous? Why try to prove a thing that does not -- cannot -- lead to a proof of the big picture?

If a ship goes far enough away you can't see it.
Even with the biggest telescope, the ship can not be seen.
Why?
Show me a Flat Earth map that works.

?

#### robintex

• Ranters
• 5322
##### Re: The Earth is flat ... ish?
« Reply #24 on: February 13, 2018, 05:54:44 PM »
In trying to determine earth curvature / non-curvature by means of looking at objects at distance over water (ship masts, Chicago skyline, bridge supports, etc.) all that is being done, or not done, is looking at the geometry in a very small localized area. A proof of curvature or non-curvature over an infinitessimal fraction of the earth does not prove or disprove a globe or non-globe.

Then why do ships disappear over if not the horizon?

A proof would be to measure amount and direction of localized curvature at one location and proceed with a network of bootstrapped subsequent points until a full globe or shown or not shown. Cherry-picking a tiny handful of points is insufficient.

So, pretty much like cell phone towers.

So why is this attempted "proof" so ubiquitous? Why try to prove a thing that does not -- cannot -- lead to a proof of the big picture?

If a ship goes far enough away you can't see it.
Even with the biggest telescope, the ship can not be seen.
Why?

Because it has disappeared after it has passed over and beyond the horizon because of the curvature of the earth because the earth is a globe and because the earth is not a flat disc.
Stick close , very close , to your P.C.and never go to sea
And you all may be Rulers of The Flat Earth Society

Look out your window , see what you shall see
And you all may be Rulers of The Flat Earth Society

Chorus:
Yes ! Never, never, never,  ever go to sea !

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #25 on: February 13, 2018, 05:57:06 PM »
[snipped irrelevance]
Having a spot of bother with reading comprehension? Jumping in with stock responses, regardless of what the question is?

Maybe go back and read the one-syllable word version.

?

#### smokified

• 386
##### Re: The Earth is flat ... ish?
« Reply #26 on: February 14, 2018, 12:39:37 PM »
The ask in the first post seems to make mad those who want to fight the view of Round Earth or Flat Earth. So I make the ask plain with use of words that each have one sole sound part.

Here is a proof folks use a lot. The proof is for a small place. Earth is a large place. As such, the proof is not a good proof. It is a poor proof for what the folks want to prove.

Why do folks use a bad proof if the proof is not what folks need to prove a thing?

The problem here, is that your entire premise is completely flawed.

The entire earth has been measured already and we know for a fact that the curvature of the earth is approximately 8 inches per mile squared.

#### Curiouser and Curiouser

• 1661
##### Re: The Earth is flat ... ish?
« Reply #27 on: February 14, 2018, 01:26:26 PM »

The problem here, is that your entire premise is completely flawed.

The entire earth has been measured already and we know for a fact that the curvature of the earth is approximately 8 inches per mile squared.

Since you seem to be having the same problem as ER22, why don't you clarify your response by telling me, in your own words, what my premise is that you consider to be flawed?

Because it appears from your response that you have no idea what my entire premise is.

Multiple responders have all jumped to the reply that the earth has been measured by other means.

Did you even read the original question?

?

#### ER22

• 393
##### Re: The Earth is flat ... ish?
« Reply #28 on: February 14, 2018, 03:27:19 PM »
[snipped irrelevance]
Having a spot of bother with reading comprehension? Jumping in with stock responses, regardless of what the question is?

Maybe go back and read the one-syllable word version.

Oh my, you have cut me to the quick!
How shall I ever recover?

Your first point was that attempting to prove curvature in a localized area etc.
My response was why do ships disappear over if not the horizon?
Terrible typing mistake should have been:
Why do ships disappear if not over the horizon?

Your next point was that multiple points should be used etc.
My response was So, kinda like cell towers.

Your final point was why is this proof so ubiquitous.
My response was simply that if a ship disappears as it sails away
Eventually you can't see it even with the biggest telescope.  Why?

And of course you don't offer an answer.
Just platitudes and bullshit.
Typical.

Show me a Flat Earth map that works.

?

#### smokified

• 386
##### Re: The Earth is flat ... ish?
« Reply #29 on: February 19, 2018, 11:38:23 AM »

The problem here, is that your entire premise is completely flawed.

The entire earth has been measured already and we know for a fact that the curvature of the earth is approximately 8 inches per mile squared.

Since you seem to be having the same problem as ER22, why don't you clarify your response by telling me, in your own words, what my premise is that you consider to be flawed?

Because it appears from your response that you have no idea what my entire premise is.

Multiple responders have all jumped to the reply that the earth has been measured by other means.

Did you even read the original question?

Yes, your original question is not worth asking because the entire earth has been fully measured using multiple different methods over hundreds of years.

Whereas you are attempting to sound smart, you are really just being a complete fool.  Go ahead and waste your time measuring buildings and landmarks.