The visible curvature seen in [url=http://www.defensemedianetwork.com/wp-content/uploads/2014/03/U-2-Dragon-Lady1.jpg]the above picture[/url] DOES NOT demonstrate that earth is round. These pictures taken from the cockpit of high altitude aircraft (pictures from NASA space craft are fake) represent the extreme upper limit of man's ability to travel so far. Here is why they do NOT reinforce the ball model of the earth: Vanishing Point + Atmosphere = distance obscured. It is the same principle at work when ships disappear or reappear on the horizon. Let me unpack this a bit... [url=https://en.wikipedia.org/wiki/Vanishing_point]Vanishing Point[/url] is a principle of perspective used in art. [url=http://www.sacred-texts.com/earth/za/img/fig75.jpg]But as this image illustrates[/url], the limitations of human perception cause vanishing point to occur at a finite distance from the observer. [url=http://www.sacred-texts.com/earth/za/img/fig83.jpg]Here is an illustration of how it works with ships on the horizon.[/url] Simply put: humans cant see outward forever. Our senses are limited both by our anatomy [i]and[/i] natural factors such as the density of the atmosphere. [b]So how does this apply to high altitude pictures of the horizon where atmosphere is almost non existent?[/b] Great question. But remember: just because you are [i]above[/i] the atmosphere, does not mean that there is not still a great deal of atmosphere below you. When you look out from the cockpit of a high flying plane, [i]the curvature you see is the curvature of the disk of the earth[/i]. [b]But the visible curve IS NOT THE ACTUAL EDGE[/b]. The earth is still physically stretching out beneath you for great distances, but the density of the atmosphere [b][u]below you[/u][/b] as well as the effects of [b][u]vanishing point[/u][/b] obscure the rest of the disk of the earth from view. [i]Note the hazy glare at the edge of earth in every one of these pictures: that's a huge part of the effect I'm talking about.[/i] [b]ATMOSPHERE + VANISHING POINT = DISTANCE OBSCURED TO THE VIEWER[/b] Tl;dr Although high altitude pictures of the earth are true, the visible curve is not the curvature of a spherical earth: it is caused by the atmosphere and principles of perception obscuring the rest of the disk from view. Edit: Thanks for the good responses. I am busy with school, but I'll try to respond to all of you as I find the time... Thanks for discussing!