True (sadly). We need an argument using LEGO.
I’ve always been amused at those who reject evolution because “it’s only a theory” yet enthusiastically use electrons, which are only a theory as well.
Tolkien explored this idea. Arda was originally flat and anyone could sail from what is now Middle Earth to Númenor and westward to Arda, the Undying Lands, but mortals were forbidden to do so. When Ar-Pharazôn was inveigled by Sauron into invading the West, Ilúvatar destroyed his fleet, pushed Númenor under the sea (I’m imagining a giant thumb descending from the sky) and to ensure that the Undying Lands would never again be threatened by mortals, bent the earth. Thereafter, only Elven ships could follow the Straight Road to Arda; the ships of Men would follow the curved surface of the earth to circumnavigate the globe instead.
As an aside, one of my relativity textbooks included a map of Middle Earth with four cities marked on it, as well as the crow-flight distances between all of the cities, and then asked the reader to calculate therefrom the radius of Middle Earth.
Don’t keep us in suspense…
At which point, the hypothetical flat earther you’re trying to convince will object that all you’ve done is found a small, inconspicuous hill on an area that looks flat. Unlike with a body of water, there’s no particular reason to accept that any such area is “flat” until you’ve measured it.
You could, of course, try to respond by repeating the experiment in lots of different places or piecemeal over a larger area. At which point you’re essentially doing a geodetic survey. That’s a) getting complicated and b) getting sufficiently complicated that it’s unlikely to meet a flat earther’s usual standard of simple, everyday measurements.
I guess I kind of have an answer to the OP
but it is still amusing to peruse the gyrations of the FECTs.
I’m probably getting whooshed here, but I suspect that that site name is meant to be parsed as “a plane truth”, not “a planet Ruth”.
Hey, all the letters were jammed together, how could I tell?
Nope.
Not so.
There are competing definitions of “horizon”. The geometrical or geodesic horizon is where an absolutely straight line from the observer’s POV intersects the edge of the planet.
The astronomical horizon is what you see from the observer’s POV looking through the actual atmosphere. Which refracts everything you see at any appreciable distance. The refraction is negligible at zenith, and is maximal when looking towards the geodesic horizon.
The Sun subtends an angle (~1/2 degree) smaller than the typical amount of atmospheric refraction. The net effect is that during many sunsets the entire Sun has dipped below the geodesic horizon while still being fully visible, albeit probably distorted, just above the astronomical horizon.
A similar effect applies at sunrise. The sun often becomes fully visible before any of it clears the geodesic horizon.
I think you may be misunderstanding what I was proposing. The flatness or otherwise of the terrain doesn’t enter into the equation …although from a common-sense, practical, logistical point of view it would obviously be more sensible to do the experiment on a reasonably flat piece of terrain.
Y’all do know what a “water level” is, right ? It’s a flexible tube, filled with water, usually about 1/2" ID, , which can be of any length you choose, with two transparent vials at either end ; in use, the meniscus of the water at either end is marked at points 1 and 2, and subsequently at points 2 and 3, 3 and 4 … and so on. The fewer the number of datum points, the more accurate the survey is.
This one is provably wrong by anyone with high-school math skills. You only need seven numbers to predict where a satellite will appear. You can grab these numbers yourself and run them through the calculator (which can easily be inspected or programmed from scratch). As it happens, I’ve done all of this, starting with the TLE (orbital parameter set) of the ISS and ending with pointing an antenna at a nice bright speck where the ISS should be, and hearing relayed messages from Colorado.
Arbitrary curves need a lot more than seven numbers to describe them, but it’s easily seen that every object needs just those. There’s no room for a conspiracy; even if all satellites were placed in orbits that somehow corresponded to elliptical orbits around a round Earth, collisions, failures, and even non-artificial satellites would show things moving in a way that needed more than the seven numbers. But it never happens.
Let me stop you right there…
You can read about the math here. The equations may look daunting, but you don’t have to understand them, just verify that they do indeed produce a prediction based only on the TLE data. And they’re all composed of basic high-school math operations like sin/cos, square roots, and so on. There’s no mysterious place where a conspiracy could hide and fudge the math. It all comes out to a few dozen lines of code (which is also easy to verify).
Well, yeah. It’s a circle because the earth is a globe. If you can see the curve of the circle that is the horizon then you are seeing the curve of the earth.
They must be doing that with lasers or something. A searchlight kind of deal. They have those set up on mountain tops, moving in slow circles to make us think there are satellites up there. The NASA scam must be ridiculously elaborate.
How that eclipse business works, though, that is hard to explain.
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You miss my point. How much overlap do you think there would be between those who genuinely can’t understand that the earth is a globe and those that can do even relatively basic high school math?
Not much, is my guess.
With the mention of satellites and orbit predictions, a thought occurs to me.
Back in the day, I would travel around a bit, and set up satellite communications terminals. Because of the directional nature of the antennas, we would have to calculate the ‘look angle’ to the ‘bird’. Because we used geostationary satellites, it was a fairly straightforward thing to do with a full function calculator and the correct instructions (which I may have around here somewhere). It could also be done with a basic 4 function calculator and trig tables (hey, it was the dark ages of the 70’s and 80’s).
If you were to calculate the look angles for, say, 200 cities in N & S America, or Africa, then project where those cities would be on a flat earth to have the same look angle, I wonder what that map would look like.
Trying to picture it in my mind, the areas near the sub-satellite point would be minimaly distorted, sure. I think the edges would just be spread out to such a degree that the distance between, say, Santiago, Chile and Buenos Aries, Argentina would be tens of thousands of miles.
Dayum, I have things to do today. This is going to be stuck in my head all weekend.
This is just a way of generating a map projection, no? In fact, if the number of satellites is small, you could just carry around a chart for each one from which you could read the bearing and elevation, no trigonometric tables required.
“Eclipse business” is absolutely right. They have been gathering tithes and fees for millennia, going back at least to ancient Egypt and Babylon. There are some deep pockets there!
Big Eclipse (in collusion with Big Globe) is responsible for the mess we’re in. That’s why we should support Flat Earthers in their efforts to set things straight and make America great again!
I really have no idea. But my observation on all kinds of pseudoscience crap is that there’s not much relationship between educational attainment and belief in nonsense. If anything, belief in pseudoscience goes down at very low educational levels because they don’t think about this stuff in any capacity. But it’s possible to have just enough enough education to get into trouble.