Photograph by A. T. Willett / Alamy

Since 1969, when an estimated six hundred million people around the world watched two astronauts walk on the surface of the moon, a significant number of people have doubted that the event ever took place. A major line of conspiracy theory insists that the footage was faked (and directed by Stanley Kubrick, some have said) in an elaborate hoax engineered by NASA. In 1976, a book called “We Never Went to the Moon” was self-published by a man named Bill Kaysing, a former technical writer at Rocketdyne who claimed to have seen secret government documents. It attracted little notice, but Kaysing continued to make media appearances and fuel doubters into this century. Andrew Marantz, who has written on conspiracy theories for The New Yorker, notes that the moon landing always had skeptics, but the Internet and social media gave them platforms to advance even their most far-fetched views. Marantz sees links between the moon hoax and political conspiracy theories like QAnon. Though skepticism toward government claims may be justified, conspiracy theories that dispute the most basic accounts of truth erode the functioning of a democracy, Marantz thinks; they lead to a totalitarian state where, in the words of Hannah Arendt, “everything was possible and . . . nothing was true.”