The youtube user, Immortalsouls, argues that the "fact" that the horizon never falls as altitude is gained is proof of a flat Earth. Here is the link to the video in which he argues this: He claims that the horizon never falling is ONLY possible on a Flat Earth. Ps. I'm new to these forums and I know this post doesn't have a whole lot to debunk. Please be patient with me. Flat earth theory is a disease rapidly spreading across the internet. I was shocked to discover that there are actually people who still believe in this.