Two Italian brothers claimed to have recorded dying Soviet cosmonauts that Moscow erased from history

The Lost Cosmonauts theory alleges that the Soviet Union launched humans into space before Yuri Gagarin's 1961 flight — and that the cosmonauts onboard died. The strongest piece of supposed evidence came from Italian brothers Achille and Giovanni Battista Judica-Cordiglia, amateur radio operators in Turin who claimed to have intercepted transmissions from doomed Soviet spacecraft between 1960 and 1964.

In the 1980s, American journalist James Oberg researched space-related disasters in the Soviet Union but "found no evidence of these Lost Cosmonauts." After the fall of the Soviet Union, much restricted information was released, including the real cover-up: Valentin Bondarenko, a would-be cosmonaut whose death during a training fire on Earth was hushed up. The actual Soviet secrets turned out to be less dramatic than the conspiracy — cosmonauts were airbrushed from photographs not because they died in space, but because they'd been expelled from the program for misbehavior or killed themselves.

One alleged lost cosmonaut, "Ivan Istochnikov," turned out to be a complete fabrication — a "modern art exercise" by Joan Fontcuberta that included falsified mission artifacts and digitally manipulated images. Mexico's Luna Cornea magazine ran it as fact.