so why do ships disappear over the horizon?

has this one been spun yet? not while I've been around, thats for sure...

Clicky.

if using a telescope, one should be able to see a ship long past a certain point, no? stars are visible over a great distance despite the "haze"

if using a telescope, one should be able to see a ship long past a certain point, no?

What "certain point" might that be?

stars are visible over a great distance despite the "haze"

Right.

Quote from: "BobDole"

if using a telescope, one should be able to see a ship long past a certain point, no?

What "certain point" might that be?

Quote

stars are visible over a great distance despite the "haze"

Right.

distance to the horizon at sea level is only a few miles

distance to the horizon at sea level is only a few miles

Right, atmospheric distortion blocks your line of sight past about thirty miles on a clear day.

Quote from: "BobDole"

distance to the horizon at sea level is only a few miles

Right, atmospheric distortion blocks your line of sight past about thirty miles on a clear day.

So what about stars visible on the horizon?

So what about stars visible on the horizon?

I have never seen any stars visible near the horizon.

How convenient.

Quote from: "Ambassadork"

So what about stars visible on the horizon?

I have never seen any stars visible near the horizon.

there are objects visible in the sky that are at a much greater distance than that point where a boat will disappear, whether the stars are on the horizon or not is not entirely important

there are objects visible in the sky that are at a much greater distance than that point where a boat will disappear, whether the stars are on the horizon or not is not entirely important

It is not the distance that matters, it is how much atmosphere you are looking through.

And where I live, you CAN NOT see stars near the horizon. I live near several cities, so the sky is much too bright for most stars to be visible, and it is not possible to see any near the horizon.

It is not the distance that matters, it is how much atmosphere you are looking through.

So you're saying that there's LESS atmosphere between you and space then there is between you and a boat you can't see?

Quite possilbly, yes.

Then why is it that when we stand on top of a 30 story building on the
seafront, we can see ships that aren't visible from the shoreline?

Surely climbing the 30 story building would only place more atmosphere
between myself and the ship on the horizon.

I've tried it, it works.

has this one been spun yet? not while I've been around, thats for sure...

Search...


Wanna play Russian Roulette? You go first.

Search...


Wanna play Russian Roulette? You go first.

*CLICK*

Your turn.

Then why is it that when we stand on top of a 30 story building on the
seafront, we can see ships that aren't visible from the shoreline?

Surely climbing the 30 story building would only place more atmosphere
between myself and the ship on the horizon.

I've tried it, it works.

Lets not avoid my question.... you Flat Earthers are good at that,
I'm not letting this one slide.

They'll just say that the atmosphere is thinner the higher you go, so there would be less "distortion" or somesuch BS...

Then why is it that when we stand on top of a 30 story building on the
seafront, we can see ships that aren't visible from the shoreline?

Surely climbing the 30 story building would only place more atmosphere
between myself and the ship on the horizon.

I've tried it, it works.

That is an example of the optical illusion that Flat Earthers use to explain the horizon.

Perhaps you could go into a bit more detail about this optical illusion for me?

Could I suggest a ray diagram? Do you know what that is?

Clicky.

I would like to point out that (once again) Mr. Rowbothman is selectively applying his reasoning only to the effect which he is trying to prove.  

I do not disagree with his first phenomenon:  details do disappear with distance.  That does nothing to explain a sinking ship, though, only that details are indistinguishable from the rest of the ship.  

Let me continue on to his second proposed phenomenon.  


This diagram is flawed.  He is assuming that when part of an object is no longer visible it is physically no longer there.  A ship would sink MUCH faster if it's hull were truly no longer there, but these ships sometimes come back.  If the object is at W then it is no longer at H, even though some detail of the object became indistinguishable at H.  Even though we can't see it, the lines of this detail must still extend to point W.  

fin

it is physically no longer there

I'm not sure what you mean by this. Would you mind clarifying?

I follow his argument, but I'm not convinced that

The smallest angle under which an object can be seen is upon an average, for different sights, the sixtieth part of a degree, or one minute in space

I'll have to verify this myself.

He also seems to have arbitrarilly chosen his angles as being between
the lines of sight and the direction parallel to the earths surface. He seems
to give no clear reason for doing this.

To put it another way...


His argument: anything visible within the angle q will disappear first as
the ship gets further out. Since we can't see anything within an angle less
than 1/60 degree



I ask: Why does the blue line have to be parallel to the earths surface.
If it was like this, the ship would disappear proportionately.

Maybe my understanding of persepctive is weak. Then again if I knew
everything, I wouldn't be posting this question.

Look at these facts:

1. Light travels at different speeds through different mediums (Scientists are reputed to have made light slow to almost a complete stop.).
2. Denser air sinks to the bottom.

If you put these two facts together and presume that the air which sinks to the bottom allows light to travel through it slower this means that light will curve downwards slightly. Now on a small scale this wont have much of an effect but on a much larger scale such as across the Earth it would explain the sinking ship effect.

Quote from: "CharlesJohnson"

Then why is it that when we stand on top of a 30 story building on the
seafront, we can see ships that aren't visible from the shoreline?

Surely climbing the 30 story building would only place more atmosphere
between myself and the ship on the horizon.

I've tried it, it works.

Lets not avoid my question.... you Flat Earthers are good at that,
I'm not letting this one slide.

It would place less atmosphere between you and the horizon.

There, you happy now?

Look at these facts:

1. Light travels at different speeds through different mediums (Scientists are reputed to have made light slow to almost a complete stop.).
2. Denser air sinks to the bottom.

If you put these two facts together and presume that the air which sinks to the bottom allows light to travel through it slower this means that light will curve downwards slightly. Now on a small scale this wont have much of an effect but on a much larger scale such as across the Earth it would explain the sinking ship effect.

I am aware of both of these facts, but as a correction on 2, the air close
to the earths surface is denser because the pressure is greater. I didnt
somehow get denser and then sink.

Apart from that, the difference in air pressure over the height of a 30
story building is miniscule, and couldn't account for reduced visibillity in
the region of a few kilometers.

It would place less atmosphere between you and the horizon.

And your reason for saying this is...?

Quote from: "EvilToothpaste"

it is physically no longer there

I'm not sure what you mean by this. Would you mind clarifying?

He's applying two different perspectives to one object.  By having point H and W represent different parts of a single object he is saying it is physically torn apart.  Namely, that the hull of the ship is at H while the mast is at W.  Thus because the hull is no longer there (invisible and at point H) the ship appears to sink.

He's applying two different perspectives to one object.  By having point H and W represent different parts of a single object he is saying it is physically torn apart.  Namely, that the hull of the ship is at H while the mast is at W.  Thus because the hull is no longer
there (invisible and at point H) the ship appears to sink.

I don't think so, he is using two separate cases. He is saying that when
the whole ship is at H, only everything above the Hull is visible. But when the ship is at W, the entire thing disappears. I don't see where he implies
that H and W represent different parts of the ship.

I may be wrong... feel free to correct me if I am  :?:

So Toms argument is invalid because refraction would only serve to cause the ship to appear more elevated than it really is.
My original question was:

Then why is it that when we stand on top of a 30 story building on the
seafront, we can see ships that aren't visible from the shoreline?

Surely climbing the 30 story building would only place more atmosphere
between myself and the ship on the horizon.

I've tried it, it works.

So I'm still looking for a Flat Earther to give me a scientific reason for this
phenomenon. If you do follow Rowbothams reasoning, then could you
answer the question posed above with the two diagrams? Thanks - CJ

Quote from: "BobDole"

there are objects visible in the sky that are at a much greater distance than that point where a boat will disappear, whether the stars are on the horizon or not is not entirely important

It is not the distance that matters, it is how much atmosphere you are looking through.

And where I live, you CAN NOT see stars near the horizon. I live near several cities, so the sky is much too bright for most stars to be visible, and it is not possible to see any near the horizon.

ever been into the countryside? you can see stars on the horizon.

I don't think so, he is using two separate cases. He is saying that when
the whole ship is at H, only everything above the Hull is visible. But when the ship is at W, the entire thing disappears. I don't see where he implies
that H and W represent different parts of the ship.

I am having a hard time explaining myself with this one, dangit.  

He's applying two different perspectives to one object.  By having point H and W represent different parts of a single object he is saying it is physically torn apart.  Namely, that the hull of the ship is at H while the mast is at W.  Thus because the hull is no longer there (invisible and at point H) the ship appears to sink.

He's not saying it, but his diagram represents it that way because there is no line from C to W.  When the ship is between H and W something funny happens:  

It's clear from this diagram that the dimensions are not proportionally preserved as distance increases (to the right).  The bottom of the object is physically gone in this diagram.  

He is assuming with this diagram that an object will be infinitely small when it disappears, contrary to his assertion that there is a finite minimum size humans can see.  Therefor, the size of the detail at H will get smaller and smaller only to a certain point: the point at which it fades from our ability to see it.  

This one would be more accurate to what he is saying (though not to scale):

Notice the white triangle on the bottom right.  Due to the limits of human vision the detail would fade away at point H, and the rest before point W (because point W should really be an asymptote, the point of infitite distance as seen from the perspective of the diagram).  

But because we can not see the height of that triangle due to the limits of our vision, how could the ship appear to sink?  It wouldn't appear to change at all because we can't see it.  That detail would merely blur in with the surroundings.