The Earth is mostly spherical.

And yes, I did not produce the number of pictures I intended to. Maybe this time will there will be more. Distances SightedThe opponent puts all his eggs in one basket here, agreeing that he must prove the skyline to be probably a real physical object, rather than an image. He argues that under a "mock-mirage" the image will be inverted. I'm guessing he misread the quote he himself referenced. "Don't confuse image inversion (i. e. , something appearing upside down -- the common property of all mirages) with thermal inversion. "As the source I referenced explains, a "mock-mirage" is a product of thermal inversion, not image inversion. I suppose the opponent saw "mirage" in "mock-mirage" and assumed it would be classified as a mirage. Note that "mock-mirage" means "fake-mirage", or more generally speaking, "not an actual mirage". The provided source explains why tall objects that should be obscured by the curvature of the Earth can be seen as a result of thermal inversion. The gradient caused by the introduction of a large body of water creates the perfect condition for a "mock-mirage" to occur. As it stands, the opponent hasn't actually demonstrated that the image is a real object. He furthermore hasn't shown that it is unlikely a mock-mirage, since his response concerned "real mirages" as opposed to "mock-mirages". As such, this point flows to me. Reflections over waterThe opponent provided a photo of a sunset, a photo of a light on a slick surface and is trying to argue that said evidence sufficiently proves. .. well, anything. My admittedly rudimentary drawing shows how light travels. In this drawing, the sun is overhead. Allow me to post another one explaining what happens at sunset. I provided a zoomed in picture, since the pad I use doesn't save in HD. There are a few things to notice:Blue Dot - This is the observer. The top of him are his eyes, the bottom of him is where he touches the earth. Red Line - This is Blue's line of sight when looking directly at the horizon. Note that the sun is passing through this, giving Blue the apparent view of a sunset. Purple Line - This is the line tangent to Blue's position. In other words, if the Earth became flat right where blue is standing, this purple line would represent the surface of the earth. Note that the sun is entirely below the purple line, indicating that it is below blue's feet from his frame of reference. Zoomed in - The portion of the sun that is above the red line will hit the water and reflect into blue's eyes. This is represented by the gold lines. The part of the sun touching or below the red line will not reflect off the surface of the earth blue can see, since it is below the horizon line. Blue would here be seeing a portion of the sun. Hopefully this simple image makes clear how light travels and reflects from the earth into the viewer's eyes, even when the sun is below the observer's feet from his frame of reference. Notably, the taller the observer, the greater difference in slope between the positional tangent (purple line) and the horizon line of sight (red line). A very short object would be unable to see much of the sun as it passed "under their feet". A very tall object would be able to see more of the sun. This is why in Dubai, you can watch the sunset on the ground, right up to the top of the huge building, then watch the sunset again. Flight PathsThe opponent let this one go. Goody for me. GyroscopesThe precession "wobble" is definitely a thing, no doubt -- but the opponent seems to miss how it is relevant to airplane gyro's, which is our discussion point. A precession "wobble" will occur when a force is applied unevenly to some portion of the outer rotating disc. The precession will continue until an equal force is (at the correct time) presented to the opposite side of the disc. With gravity, the force is being constantly applied to all parts of the gyroscope. If we consider a non rotating disc locked into a gyro that has its center of mass down, angling the disc will cause it to try and "fall" back into its normal, level position. When rotating, the gyro will not attempt to fall back into its level position, but instead begin to "precess" into a perpendicular position. Here's the important part: The precession wobble will quickly be reduced, since gravity will continuosly try and bring the "higher" portion of the disc toward the "level position". In other words, gravity is constantly acting on a gyroscope, meaning that the precession wobble will constantly be moved toward a smaller wobble. The gravitational vector slowly changes as one moves across the earth, meaning the induced precesssion is always small and is quickly made nill by the continuous force of gravity. So yes, a precession wobble does occur and it would keep occuring if gravity was a "one time force". However, it is constant, meaning the wobble quickly diminishes until it comes to rest in its lowest energy state. The opponent's question was a good one -- and I'm glad he allowed me the opportunity to explain this to the voters. It's not initially clear why there is not a precession wobble constantly occuring on an earth gyro. SatellitesTracking SitesThe opponent is confused regarding the word "fake". Yes, tracking sites do not always "really know" the position of the ISS, since they are not continuously fed data from NASA. Instead, they rely on a mathematical formula to derive the position of the ISS. Notably, if the voter wanted to test out whether this actually worked, they could get the next passover from a tracking site and see that yes, the ISS actually does pass over. These sites work, so it's hardly apt to call them fake. As for the photos and videos of the ISS close up, these are literally everywhere. However, the opponent has claimed that the space agency commonly produces hoaxed images and videos -- meaning if I did present these, the opponent would just say they're fake. You can't complain that there dont' exist photos and videos, then say that we're not allowed to consider photos and videos from a governmental space agency. Obviously the only people capable of getting a "close shot" of the ISS are space agency astronauts who are physically close to the ISS. U2 PlanesI suppose I have to admit -- it's "possible" that the ISS is a hologram being projected underneath a plane. .. . a plane with an infinite amount of fuel that moves at bewildering speeds. The ISS is constantly seen by the public, meaning the plane would need to be in the air at all times. Another plane could not come in and take its place, since the hologram would "die" for a time and someone would notice it. I suppose the plane could be constantly refueled though, so let's consider speed. The ISS is claimed to move at about 5 miles per second. A closer object wouldn't need to move that fast in order to match the apparent speed. It would be close though:Circumference of 250 m orbit = PI*diameter = PI*(8000miles + 2*250 miles) = PI*8500 milesCircumference of 7 mile "orbit" = PI*d = PI*(8000 + 14) = PI*8014 miles. So a U2 plane projecting a hologram would need to move at (PI*8014) / (PI*8500) times the speed. This is: (5 miles / sec) * [ (PI*8014) / (PI*8500) ] = (5 miles / sec) * (8014/8500) = (5 miles / sec) * .94 = 4.7 miles / sec. Simply put, we don't have planes that fly anywhere near that fast. In fact, a plane could not fly that fast without being ripped to shreds by the frictional forces of the atmosphere. So holograms == not a possibility. ISS too far to seeThe opponent's argument seems to be "this particular camera can't see that far", which ignores my entire argument. Again, the ISS is bright, allowing the light to be seen at long distances. Just as you can see a tiny light on a plane that's 7 miles up, you can see the giant light reflected from the ISS 250 miles up, just as you can see Polaris, which is over 400 light years away. Light continues to travel, despite the distance between the viewer and the light source. If there is enough light travelling, the human eyes will see it. RadiatorsAs I said, the atmosphere is very thin. The particles in this atmosphere are very hot, but also very sparse. The particles in a solid space craft are very compact. This is why a solid radiator can "vent" heat into the thin, hot atmosphere. Heat transfer can be thought of as happening to balance the "heat / unit^3" of two objects. In other words, a radiator will continue venting heat until the amount of heat in a one cubic centimeter of radiator is equal to the amount of heat in one cubic centimeter of "outside air". Let's be generous and say that the thin atmosphere has 1 hot particle / u^3 and a radiator has 10 hot particles / u^3. Let's say "hot" is 1000K. The atmosphere would have 1000K worth of heat / u^3 while a radiator has 10000K worth of heat / u^3. The radiator would continue venting in this case, since it contains much more heat than the atmosphere around it. This is a common misinterpretation in science. The amount of heat a collection of particles has is different from the particle's temperature. A 1x1x1 solid with a particle temperature of 1K contains much more heat than a 1x1x1 thin gas with a particle temperature of 1000k. This is why radiators work in the thin thermosphere. In fact, this is why they work pariticularly well in the thermosphere. Sat phonesThe opponent presents a picture that seals the deal on my argument. Clearly sat phones work over large swaths of the ocean where no cell towers are present. Note that you get coverage over almost the entire span of the Atlantic ocean from NY to London. ConclusionI've demonstrated that sats exist. I've demonstrated that sats only work on a globe, indicating that the earth is round. I've also shown the opponent has not proven the earth is flat in any measure. As such, I have won today's debate.