The US was in a space race with the Soviet Union during the Cold War and could not hand a win to the communists. As a last resort they reached for fabrication, the disbelievers say.

As evidence, a favourite of the doubters is the waving flag that Armstrong and Aldrin planted in the moon's surface. How was it waving if there is no air on the moon? In actuality, the flag was equipped with a bar to keep it extended rather than hanging limp and the ripples in the cloth were due to its folding in the packaging.

Additionally, a shot of the flag actually moving was caused by an astronaut letting go of the cloth.

Then there is the issue of missing stars. Why were there no stars visible in the television pictures? The National Aeronautics and Space Administration (NASA) has responded that starlight is too weak to appear in photos under normal lighting conditions on the moon -- a phenomenon also well known to every photographer on Earth.

As for the 'false shadows' in NASA pictures, objects and people appeared to cast shadows in different directions rather than in parallel directions. Because the sun is the only light source on the moon, sceptics have used this as evidence that it was all filmed in a Hollywood studio with multiple lights. The experts' answer: The moon is not flat, meaning there is no 100 percent 'correct' shadow. This can even happen on Earth.

Launius calls the theories 'silly', but admits they aren't going away any time soon.

'It would be the coolest thing on Earth to go back to the moon - just to prove that we have been there before,' he said.