How do you see something at eye level that is really 15 miles lower than you?Standard answer: You can't! Your eyes lie to you.Basis for conclusion: Some "smart people" have worked it out, and tell us this.Reason to accept what they say: We can't trust our own perceptions, and aren't smart enough to figure it out ourselves. They have letters behind their names, and do lots of deep thinking.Reason for thinking this: Some "smart people" have worked it out, and their findings tell us what we see can't be trusted. This means that everything we perceive is suspect, and needs checking in with some "smart people" to see what is really gong on.Result: We stop believing anything we perceive on our own that involves the world we live in. Now we have been trained, and our trainers can tell us anything they want. They can tell us the moon is more than 200,000 miles away even though we can pick out details with the naked eye. They can tell us that stars are trillions of miles away even though we can focus in on them with a zoom camera. They can tell us that the sun is 93 million miles away, and yet, from a weather balloon at 20 miles up it looks like you could almost touch it. They can tell you that water always seeks it's own level, and it also conforms to the shape of a ball because of gravity? They can tell us anything now that we have been trained to disbelieve our own brains. They can tell us that earth is spinning 1000 mph, orbiting the sun at 66,600 mph, all of that spiralling in some direction at 200,000 mph, all of that rotating at 2 million mph around the galaxy, and we don't feel anything. And the north star stays continuously centered above the north pole through all that. And the constellations maintain a continuous rotating position around it through all of this? They can tell us that a mysterious force called "gravity" is responsible for orbiting bodies as well as for falling bodies. They can tell us the earth has a molten core a couple of thousand miles down, but have never dug any deeper than 8 miles.End result: In addition to being trained to depend completely on "smart folks" to tell us what to think, we have also been programmed to defend to the death, and to perceive as a personal attack any forays into thinking for one's self about these subjects. This is why there are so many ardent defenders of a model that is impossible to defend.I did bother to read those articles. I cannot verify those calculations. I either believe my own eyes, or I just push it back in my mind, and make excuses for it not jiving. If I am in a plane at 40,000 feet, when looking straight down it is seen to be a long ways down. It only follows that at the horizon 245 miles away where it is said to be 40,000 feet lower than directly beneath me, that it would appear to be a longer ways down than that. If you trust your own eyes, this is your expectation. By the formula for curvature that science has given us, the earth is not really that big. The size of the USA keeps changing though. (I know, nasa has a good explanation for this. They always do! They are completely trustworthy, and would never lie.)https://flatearthperspectives.wordpress.com/2016/03/01/official-nasa-so-called-photos-of-earth/It just seems that all of the science given to us by "smart folks" explains away many things that we perceive with our own senses that point to a fixed, motionless plane earth with sun, moon, stars, and wandering stars travelling above us.