As Fox Mulder often said on The X-Files, when it comes to space aliens “the truth is out there.” But in each one of these cases, the “truth” wasn’t.

The Great Moon Hoax (1835)

A writer for a The New York Sun claimed to have spotted strange creatures running around on the moon, and detailed his findings in a series of six articles. To lend further credence to these bizarre claims, he said that astronomer Sir John Herschel had used a powerful telescope to observe unicorns, beavers, bison and bat-like humanoids running around on the lunar service. The hoax helped boost the paper’s circulation and, while they never printed a retraction, many staff members later said that the articles were intended as satire (even though a group of scientists from Yale were among those who were duped). Herschel himself found the articles amusing…at first. After a few years of being routinely asked about the moon’s supposed residents, he admitted that he was really sick of getting bugged about them.

The Maury Island Incident (1947)

That June, two harbor patrolmen named Fred Crisman and Harold Dahl were cruising the waters of Puget Sound outside Seattle when they supposedly spotted six “doughnut shaped” UFOs in the skies over Maury Island. [According to the duo, one of the UFOs dropped a strange black substance onto their boat that broke one of their colleague’s arms and killed a dog on board. If this story couldn’t get any weirder, Dahl claimed that he was later contacted by a government agent dressed in a black suit who told him to never talk about what happened. While the incident helped give rise to all of the urban legends surrounding “Men in Black,” Dhal confessed years later that the whole thing was a hoax.

The Little Blue Man Hoax (1958)

In early 1958, motorists in rural Michigan began reporting sightings of a glowing alien running amok. Several people pulled over to look for the alien only to discover that it had disappeared without a trace. Local police launched an investigation that led them to three young men named Jerry Sprague, Don Weiss, and LeRoy Schultz. The trio admitted that they were pranksters and showed the authorities the alien costume they had made out of long underwear, gloves, combat boots, a sheet and a football helmet with some blinking lights attached to it. They confessed to staging the stunt no less than eight times and the cops let them go with a warning.