You can disprove globe earth with basic math, too. Circumference around equator = ~24,100 miles Extent of viewing distance at 36,000 feet = ~211 miles Formula for circumference of circle = C = 2πr Formula for radius can be derrived = r = C / 2π Radius of Earth given aforementioned circumference = r = 24,100 / 2π = ~3836 miles You can see a mountain 200 miles away from 36,000 feet (curising altitude of most commercial airliners) 200 miles is ~0.83% of the circumference of the Earth If you travel half the circumference of a cirlc,e you've traveled the entire radius Thus, 200 miles, or ~0.83% of the circumference would be ~1.66% of the radius 3836 Miles * 1.66% = ~63 Miles Therefore, the mountain you're looking at that is 200 miles away is, allegedly, 63 Miles DOWN the curve of the earth. Now I wait for the response about "but muh light bending correlois effect!" You can see a ship sail "down the curve" and watch is descend into the horizon. Makes sense with globe earth theory, but one can take a telescope, or a powerful camera like a P900, and zoom in from the same viewpoint, and see the ship again. How can that be if the light has *already bent* along the curve of the earth before the photons have collided with your retinas? The telescope/camera is receiving the exact same photons of light, then magnifying a small subsection of it. How would that magnification, *post-bending*, affect the light bending along the curve of the earth? ... You can ban me now.