From Florida to Texas to California and lots of places in between, people from secretaries to rocket scientists worked to fulfill President John F. Kennedy's challenge to put Americans on the moon by the end of the 1960s.

Mission accomplished came on July 20, 1969, with a massive worldwide audience watching as Neil Armstrong and Buzz Aldrin descended form the lunar module and Armstrong, the first man to step on the moon's surface, proclaimed, "One small step for man, one giant leap for mankind."

Yet half a century later, despite other moon landings, moon rocks and firsthand accounts from countless members of the 400,000-strong workforce who helped achieve JFK's goal, some still believe the moon landings were staged in a Hollywood studio. The deniers claim the government and CIA are behind the cover-up to deceive Americans.

In fact, a poll conducted by Ipsos on behalf of C-SPAN in June 2019 revealed that 6% of Americans believe the moon landing was staged – and even more respondents,15%, said they don’t know if it was real or fake.

In the running for most famous of the deniers might be Bart Sibrel, a 55-year-old Tennessee resident notorious for having been punched in the face by Buzz Aldrin in 2002 after Sibrel confronted Aldrin in person, calling him a liar, coward and thief.

Aldrin was not prosecuted as police determined he'd been provoked, and that punch earned him accolades from many fed up with the conspirators.

"I went from being the biggest fan of the 'moon missions' to being their biggest critic," said Sibrel in emails to Florida Today in early July.

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Stating the moon landing was a "Cold War CIA and Nixon administration deception," Sibrel said he has a compilation of "riveting" and "compelling" evidence that reveals the entire space program to be a hoax. Sibrel said his evidence consists of "recordings, photographic analysis, and high-profile interviews with those involved in the space program."

"Not a single critic has ever explained, in this federal government's alleged picture from the moon, how two shadows in sunlight, from objects 5 feet apart from one another, can intersect at 90 degrees," Sibrel wrote.

"Go outside yourself and see if this can take place in sunlight. It is completely impossible."

Sibrel, like many other moon landing conspiracy theorists, is referencing a picture in which an astronaut is seen taking a moon stroll. The deniers say no way can the astronaut's shadow not be parallel to the moon rocks.

In an effort to put the uproar of denial to rest, MythBusters – a TV show that puts myths and urban legends to the test – recreated a lunar photo shoot in 2008. After they constructed a moon-landing scene to scale and adjusted the topography to mimic the moons, they discovered the sun-like lamp shining on the uneven surface did indeed cast non-parallel shadows on the mini-astronaut and imitation moon rocks.

"I get so exasperated when I talk to people who are so convinced that the moon landing was faked," said NASA historian, Bill Barry to Florida Today in September of 2018.

"The moon landing had people working on the project from all over the world, not just in the U.S. – 400,000 people in America were working on that project, how could you have possibly kept a secret like that?"

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Yet the conspiracy persists. A 1976 book "We Never Went to the Moon" written by the late Bill Kaysing, an early moon-landing doubter, is still quoted today.

Even NBA player Stephen Curry, point guard for the Golden State Warriors, has chimed in on the topic. In a December 2018 interview on a podcast called “Winging It," Curry said he doesn't believe that humans actually landed on the moon. His comment resulted in NASA, Boeing and others reaching out via Twitter to welcome Curry to to their facilities to show that humankind did indeed do just that. Boeing tweeted: "Hey @StephenCurry30, while you’re down visiting @NASA_Johnson, we’ll teach you how to fly the #Starliner to the @Space_Station. Wonder how much vert you can get in zero gravity?"

Curry later said he was joking.

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Sibrel also claims there was no independent press coverage of Apollo 11.

"The only evidence submitted to support it was entirely controlled and provided by those perpetrating the fraud," said Sibrel.

While NASA was the only entity capturing footage and photos of the moon landing via the Westinghouse slow-scan lunar camera, they had help from additional teams. A satellite in the Northern Hemisphere (California) and a satellite in the southern hemisphere (Australia) were needed to capture signals from the surface camera to relay pictures and video back to mission control in Houston in order for the moon landing to be broadcast live to 650 million global TV viewers.

In his email to Florida Today, Sibrel expressed concern about his words being included in a "pop culture" article on "doubters," saying he was saddened that the American population refuses to "be a part of changing the world by exposing "deplorable corruption.'"

"I am not the story, the fake moon landings are the story," he said.

Follow Olivia McKelvey on Twitter: @olivia_mckelvey