https://news.yahoo.com/flat-earthers-being-serious-135841693.html?
Of all the conspiracy theories that litter the Internet, the flat Earth conspiracy is quite possibly the most curious. After all, the ancient Greeks figured out the planet's shape (and even its circumference) in the third century B.C.
But a fringe society founded in the 1950s, dedicated to insisting that the Earth is flat, has given rise to a modern ground of flat Earth adherents. These believers claim that the Earth is a flat disc, and that evidence that it is round — say, pictures taken from space — are an elaborate hoax involving multiple governments. Opinions differ on exactly how the flat Earth works, with believers concocting elaborate versions of physics and creative interpretations of the solar system to make their theories work.
No one knows how many flat Earth believers are out there. According to Smithsonian Magazine, membership in the Flat Earth Society, founded in 1956, once reached 3,500 people. Today, the society claims more than 500 members on its roster. But some believers want nothing to do with the Flat Earth Society, according to a 2019 CNN article, with some attendees of the Flat Earth International Conference in Dallas that year telling the news agency that the organization is a government-sponsored front designed to make Flat Earthers look bad. (The Flat Earth Society responded to this by telling CNN, “We are not a government-controlled body. We're an organization of Flat Earth theorists that long predates most of the FEIC newcomers to the scene.”)