Cameras with a fisheye lens are used in the ISS, high-altitude balloons, rocket bodies, and other purposes. The reason is that fisheye lenses have several advantages over rectilinear lenses.
Flat-Earthers claim there is an evil intention behind the usage of fisheye lenses. In reality, the use of fisheye lenses is not unreasonable. If it is desired to have a rectilinear image output, then it is not hard to defish fisheye images to rectilinear ones..
Continue reading “Why Fisheye Lenses Are Used”
Many misinformation within flat-Earth communities is present only because of their lack of understanding on how forces work on an object.
Continue reading “Force Vectors”
High-altitude balloon footage is often abused by flat-Earthers to show us that the Earth is flat when seen from a high altitude.
We analyzed more than two dozens of footage taken from high-altitude balloons on YouTube, and we can easily conclude the curvature is there and usually easy to spot, including in the cases where flat-Earthers use the video as ‘proof’ of a flat Earth.
Continue reading “Curvature of the Horizon in High-Altitude Balloon Footage”
A hot air balloon rises because it has buoyancy. Buoyancy is the upward force that is exerted on the trapped hot air because its density is lower than the surrounding air. If buoyancy is greater than the force of gravity — or the weight of the balloon—, then the balloon will rise.
The basic physics escape most flat-Earthers. To them, the fact that a hot-air balloon rises is an ‘evidence’ that gravity does not exist. They believe things go up or down because of density. They are wrong.
Continue reading “Hot Air Balloon and the Force of Gravity”
Little Piggy is the nickname of a helium balloon launched by IndianaCaver. It reached the altitude of almost 37 km before it finally ruptured and fell to the Earth. Before that, it took several hours of video, and IndianaCaver made these video available on YouTube.
Then, some flat-Earthers cherry-picked bits of the video where the horizon looked flat and presented it as ‘proof’ of flat-Earth. These are widely circulated in various memes and forms, even years after the originals were published.
But, can we use these videos as ‘proof’ of flat-Earth?
Continue reading “The Little Piggy Balloon Footage Proves Earth is a Sphere, not Flat”