the sun goes down and comes up, it doesn't disappear off into the distance and then get closer from someplace far away ships also disappear over the horizon, bottom first and mast last. Plenty of people have measured the curvature on land and sea. the same constellations in the S hemisphere are inverted. These are basic observations that are not explained by a flat-earth model, but are obvious on a globe. The force that holds everything onto the globe has been a problem of natural philosophers for thousands of years. Some of the first actual measurements are only happening in the last decade. https://www.livescience.com/physics-mathematics/record-br…