It is perhaps the most iconic image of the 20th century: man landing on the moon, planting an American flag and saying those famous words: "…one small step for man; one giant leap for mankind."
It was an incredible feat. So incredible that many found it hard to believe at the time.
Val Germann, president of the Central Missouri Astronomical Association, said his own grandmother was a skeptic.
"It didn't resonate with her or mean that much to her. She said, 'I don't think that really happened."
"I said, 'Oh they did [walk on the moon]. I know it's hard to believe but they did.'"
Germann, 59, has spent a lifetime studying space: He taught astronomy for more than 20 years at Missouri's Columbia College before retiring. For years he has fielded questions about moon landing conspiracies from curious students, but an online poll conducted earlier this month by Britain's Engineering and Technology magazine was the last straw.
"That is what really made me angry. I'm going, 'This stuff is still going around?'"
The poll claimed that 25 percent of British people "don't believe the Apollo 11 moon landing." Germann decided to prepare a PowerPoint presentation debunking the theories of the moonwalk naysayers and present it on Monday, the 40th anniversary of the Apollo 11 moon landing. He's expecting more than 100 people to show up.
"What's going to seal it is the new lunar reconnaissance mission," Germann said. Click HERE to learn more about the images Apollo left behind.
For the majority of people in the U.S., there's no doubt that the moon landing happened. Just six percent of Americans think the government staged the Apollo moon landings according to a 1999 Gallup poll, the most recent data available. A similar poll by Time/CNN, conducted in 1995, also revealed that six percent believe the moon landings were faked.
Moonwalk conspiracy theories still live on, in large part thanks to the Internet. As the 40th anniversary of the moon landing approaches, the phrase "apollo moon landing hoax" is one of the top 10 hottest searches on Google, perhaps aided by NASA's recent announcement that they accidentally erased the original moon landing footage.
NASA's mistake also caught the attention of Nashville filmmaker Bart Sibrel, one of today's most vocal skeptics decrying government-sponsored moon fakery. He claims the tapes weren't accidentally erased because "they long ago disassembled the machine that could play or record them" and is currently working on a book based on his 2002 documentary, "A Funny Thing Happened on the Way to the Moon."
Sibrel is perhaps best known for a 2002 incident where Buzz Aldrin punched him on camera after Sibrel called Aldrin a thief and a liar during an interview for Sibrel's film. At the time Sibrel had asked Aldrin to swear on a Bible that he had walked on the moon.
Several years ago NASA responded to the public's conspiracy fascination by asking Jim Oberg, a former space engineer and the author of 10 books about space flight, to write a book for teachers, challenging the "evidence" presented by moonwalk skeptics who claim NASA faked all six manned lunar landings. But the project was cancelled in 2002 due to political pressure. Opponents suggested the money spent to hire Oberg would be a waste, and the project would end up acknowledging, and therefore lending some degree of credibility, to a small group of conspiracy theorists.