Seeing the Curve: Evidence, Geometry, and Earth's Shape

Is the Earth actually a globe? This course builds the case from scratch using observational evidence, human eye physiology, and the real geometry of horizon curvature. You will learn why you cannot see the curve from the ground, what altitude you need and why, how atmospheric refraction affects the apparent horizon, and how to work through the maths yourself. Finish with an interactive simulation and a quiz.