You never verify the shape of the floor by looking at the patterns on the ceiling.
Sometimes we can. For example, if the patterns in the ceiling are getting bigger, without the shape changing much, we can conclude that the level of the floor is rising.
This does not correspond to the Earth/sky situation, though. What we can conclude, though, is:
1. The stars must be very, very, far away compared to distances on the Earth, because otherwise the shapes, sizes, and relative positions of the constellations would look different viewed from different locations on the Earth, but they don't.
2. Since the stars are very distant compared to distances on the Earth, the starry sky would look exactly the same for all observers on the Earth who are looking at it simultaneosly, if the Earth were flat, but it doesn't. Hence, the Earth is not flat.
If I tell you the floor of my house is level, and you argue "No, the disco ball on the ceiling is spinning, therefore the floor must be a sphere," you’d be laughed out of any engineering firm.
Of course, because this doesn't follow. But the conclusions above do follow.
If the ground is flat for 1,000 miles, your "stellar parallax" math is just a spreadsheet for a broken machine.
If the ground would be flat for 1000 miles, all people on that flat plane watching the starry sky simultaneously would see the same thing. They don't.
The Ostrich Paradox:[/b][/color] You call us ostriches? Erland, an ostrich buries its head in the sand to hide from reality.
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I just wanted to use a simple word, but actually, it was misleading by me, because ostriches do not bury their heads in the ground to hide from something. That is a so called factoid.
You are burying your head in the stars to hide from the ground. You ignore the fact that water always finds its level.
It does, but that level is curved on the Earth.
You ignore the fact that there is no measurable drop-off over the horizon.
One day in June 2014, I was on a ferry between Hirtshals, Denmark and Kristiansand, Norway. I thought I would really see that the Earth is round. So I stood at the stern with a pair of binoculars and watched Hirtshals disappear further and further into the distance. I particularly looked at the Hirtshals lighthouse, which stands on a hill. At first it was slow, but gradually the lighthouse sank further and further below the horizon, before finally the top also disappeared. This fits perfectly with the fact that "the drop" is approximately proportional to the square of the distance. I also saw another ferry going from Hirtshals to another Norwegian city: Arendal. As this ferry and mine moved away from each other, I could see this one disappearing from the bottom up.
So I could observe "the drop". It really exists. These observations cannot be explained if the Earth is flat.
You ignore that pressurized gas requires a container.
You have no evidence for that. And it is well known that air pressure decreases by altitude.
I’ve seen those "arguments" a thousand times. They all boil down to: "I see things move in circles above me, therefore I must be on a spinning ball." No, Erland. That only proves Things Move In Circles Above You. It doesn't prove the ground is moving. In a geocentric, flat-earth system with a dome, the luminaries move exactly as we observe.
They don't, as the observations of the stars, sun, moon, etc. show. You may have heard the arguments a thousand times, but you have never successfully refuted them, because they are valid.
If you want to be a real scientist instead of a "recitation machine," stop linking forum posts and provide one thing: The physical measurement of Earth's curvature. Not an angle of a star, not a sunrise time—show me the Geometric Drop of the Earth’s surface. If you can't find it on the ground, your "astronomical arguments" are just fairy tales written in calculus.
These posts are written by myself and they are based on my own observations. These observations are real, not fairy talles. For the drop, see above.