Well no, Tradman has got a point. There's an angle of resolution, if you look at a far away object which is relatively flat, it will be harder to make out with increasing distance. There's a point where you won't see it from a low angle of resolution, but will see it from a high angle.

I made a little demo for how the field of view changes with height. The ball is the viewer, the red object is being looked at. You're exposed to much more of the object when you get higher.

However, this does not prove the Earth is flat. It was just about angle of resolution. If you take a telescope, your angle of resolution will not be a problem anymore. And in practice you don't see across the complete Earth, because the far away parts of the world are always disappearing below the horizon. You can't see the skyscrapers of Manhattan from, say, Lisbon, across the Atlantic in Europe, with a telescope that can resolve details of far away celestial bodies. That makes you think

Cool video, but we're not talking about how much of a flat object you can see from various angles. Trad said you can see objects better if you are higher off the ground. We are speaking of things that are fairly vertical, or that we are not trying to see the tops of, such as ships or skyscrapers. I submit that Trad's claim is false, that it is not more difficult to see objects at a distance, in general, when one's point of view is near the ground than when it is higher up.

These people who defend globe earth don't even know their own "scientific facts" about the earth's curvature.    On the one hand, they say the "earth is too big" to notice the curve;  on the other hand, using their own calculations, such curvature isn't seen in experiments.  It's quite the con game.

I said that an object moving off to the side is too close to see it appear to tilt away from you. That's a different thing from having the horizon come between you and a distant object.

Cool video, but we're not talking about how much of a flat object you can see from various angles. Trad said you can see objects better if you are higher off the ground. We are speaking of things that are fairly vertical, or that we are not trying to see the tops of, such as ships or skyscrapers. I submit that Trad's claim is false, that it is not more difficult to see objects at a distance, in general, when one's point of view is near the ground than when it is higher up.

If meditating on it doesn't help, go experiment. 

The ship disappears because of the limits of the human eyeball, which is designed to see colors/shapes and has limitations on depth and distance.

I don't know about that Pax, I remember a few different times when I was looking through the telescope at a ship disappear under the horizon, the telescope was definitely more than powerful enough to see well past the 100 miles or however far away the ships were. Which to me means that it seems if we have a FE, then from where I was, I should have easily been able to see well past those ships and see Europe or Africa or some other major land mass, or some evidence, even hazy evidence of some other land on the other side of the Atlantic ocean from Melbourne Beach, Florida - no?  

Heck, from where we were to the Bahamas is what, only about 300 or 400 miles away, but we couldn't even see them with a telescope, which seems like we should have been able to with FE.

I can field that one, even though I've only watched a few videos.

There IS water vapor in the atmosphere, especially when you're over water. Your view will "blur out" before you can ever hope to see that far away. It's the cuмulative effect of all the water droplets in the air.

Interesting you bring up telescope; usually these horizon tests are done with a Nikon or other high-zoom camera. I wonder what the difference is. Maybe a telescope isn't made for the 30-100 mile range? I'm not a telescope guy; you tell me.

I don't know much about telescopes either, but like everything my millionaire boss had, it was definitely a high end telescope, it was a spectacular thing to see when he zoomed it into the sun and moon, it would even automatically move with them, otherwise they would rotate right out of view and you'd have to keep moving the telescope. 

When he aimed it at a ship way, way out there, I really would not have guessed a ship was even out there with the naked eye, it more looked like a dot or a bird or something on the horizon, but with the telescope on a clear day, you could make out the name on the ship.  

I just thought of another problem with the FE theory, how do you explain comets that have a predictable appearance. 

On a spherical earth the visual range of a sailor is limited due to the curvature of the water. On a flat earth, the water is plane, and the visual range of the sailor is not geometrically limited.




Therefore, a crow's nest is useful on a spherical earth, and useless on a flat earth.

Let's quantify the usefulness on a spherical earth:


R: radius of the earth 6371km
h: height of the sailor above water
d: visual range

We have a right-angled triangle given by the tree points:
- center of the sphere
- crow's nest
- limit of visual range

(R + h)² = d² + R²
<=>
d = √((R + h)² - R²)
<=>
d = √(R² + 2Rh + h² - R²)
<=>
d = √(2Rh + h²)

Here some example values:

h = 2m  => d = 5.05km
h = 5m  => d = 7.98km
h = 10m => d = 11.29km
h = 20m => d = 15.96km

Let's assume, the deck of the caravel of Columbus is 5 meters above the water, while the crow's nest is 20 meters above the water. Let the speed of the vessel be 4 knots, or 7.4km/h. Then the shore is visible more than one hour earlier from the crow's nest than from the deck.


Arrival of Christopher Columbus in Santo Domingo.

Pax, this doesn’t make any sense. How come you can still see the top of the ship then? How come you can still see the moon and the stars? Even on the FE model, the moon and the stars must be many miles away, they have to be way farther than the ship.

There's more water vapor/humidity right over the ocean (plus waves) vs land, that can obscure long-distances.