The Earth is Flat

The earth is not flat, I have multiple arguments to prove this. Pictures from orbit Ever since 1946 (1), we have been able to photograph the earth from space. Every single one of these photographs show a roughly spherical earth and there have been no real photographs of a flat earth. This proves beyond reasonable doubt that the earth is not flat. Horizons If one was to be placed in the middle of a becalmed ocean on a flat earth, the observer should be able to see the coastline through a telescope even if it was 1000 miles away. This is because there would be no obstruction to the light reflecting off the coastline and into the observer's eyes. However, in reality this is not the case. No matter how good my telescope is I cannot see the coastline if I am placed in the middle of, say, the Pacific Ocean. Therefore there must be an obstruction that prevents the light reflected off the coastline from reaching my eyes. As we do not see a ridge of water in the ocean, what then is the obstruction? If the earth was flat then the obstruction could only be a hill or ridge, but such forms cannot be formed by water. Therefore, the earth cannot be flat. The Moon We know that the moon is circular, as we have observed full moons. However, we also observe that the moon can appear to have a crescent shape. This change in shape is not caused by the moon being diminished in mass, because we can see a very faint outline of a circular moon even when only the crescent part is illuminated. This suggests that the change in apparent shape is caused by a change in the way that the moon is illuminated - it goes from being fully illuminated to being partially illuminated. We know that the moon is illuminated by the sun (2), and that the sun's light is constant (3), so any lack of illumination is caused by a shadow. As the earth is the closest large celestial object to the moon, it is reasonable to suppose that this shadow comes from the earth. In order to move from illuminating a circle to illuminating a crescent, the shadow must be circular (4). As this shadow is caused by the earth, the earth must be circular in order to cast this shadow and so the earth is round. Time Zones The existence of time-zones (5) logically entails that the sun is observable at different times at different points on the earth. If the earth was flat, then the sun would be observable and non-observable at the same time everywhere in the world. As this is not the case, the earth cannot be flat. I will now respond to my opponent's argument. I agree that it does not feel like you are going up/down a hill when you walk for hundreds of miles, but this does not prove that the earth is not round. The only reason that people 'feel' an incline is not due to an actual change in orientation but a change in the angle between one's posture and the source of gravity. Therefore, on a hill the incline is felt because there is a change in the angle between one's upright posture and the source of gravity (the core of the earth), whereas the incline is not felt when walking round the earth because one is always standing upright in relation to the earth's gravity. Therefore, the earth is not flat. (1) http://www.universetoday.com... (2) http://www.universetoday.com... (3) http://space-facts.com... (4) http://en.wikipedia.org... (5) http://www.timeanddate.com...