Below: The 10 Wildest Theories Against the Moon Landings

And what prize did they bring back from this momentous journey? Well … they have a bunch of black and white photos of unidentifiable persons in bulky white spacemen costumes in a field of gravel (but curiously without any stars in the black sky) -- and several bags of gray, dusty rocks.

Put that way, the story of the Apollo program can sound pretty far-fetched.

But why should we believe the stories? What evidence is there, really, that the Apollo program landed men on the Moon and brought them back?

Phil Plait, an astronomer at Sonoma University in California, and the Web master of BadAstronomy.com, has his reasons.

"If I were trying to fake this, I would put stars in the image," he said referring to the complaint made by hoax proponents that the Apollo photos lack stars. If this had been an oversight, he said, it's an amazingly stupid thing to have forgotten, considering the scope of the "hoax."

Not to mention that with the way cameras work, photographing stars under those conditions would have been nearly impossible.

"If you do know about physics and photographs, you can see these arguments are all ridiculous," Plait said.

So why do people even give an idea like this a second thought?

"I'm not exactly sure," said Plait, "Michael Shermer is a renowned skeptic… and he has a list of reasons (such as) we have an innate thing inside of our brain, we have a need to believe."

"But one thing he leaves off, is that some of these things are just believable. If you don't know much physics, these arguments might sound convincing."

Besides, Plait says the political realities of the time would have made a fraud of that scale almost impossible to pull off.

"We went to the moon to beat the Soviets. If the Soviets had suspected that we faked these missions in any way, they would have been screaming at the top of their lungs."

The Claim: The American flag appears to wave in the lunar wind.

The Science:  If you look closely, you will notice the flag's edges are pulled taught. This effect, which was done purposely as to not allow the flag to just hang flat, it was created by inserting a stiff wire into the fabric. The "flutter" was created as the astronauts worked to erect the flag. As the wire was adjusted, "Old Glory" appeared to wave.

The Claim: If the astronauts had left the safety of the Van Allen Belt the radiation would have killed them.

The Science: The Van Allen Belts are created by Earth's magnetic field, and protect the planet from dangerous solar radiation. The belts collects this radiation, and traps it in a layer surrounding the Earth. But unless you deliberately caused your spaceship to hover within this layer, for many hours or days, the radiation exposure is well below dangerous levels. The Apollo astronauts passed through the Belts in less than four hours total for the trip. "It's not much more serious than getting a chest x-ray," said Plait.

Outside the belt, the radiation drops to low levels that are only dangerous over extremely long periods of time.

The Claim: Multiple-angle shadows in the Moon photos prove there was more than one source of light, like a large studio lamp. 

The Science: The astronauts were taking their photos on a hilly, brightly-lit landscape while the Sun was close to the horizon. Imagine taking a photograph of someone on a rolling, uneven field of snow during a full, low-hanging Moon. The contours of the ground would produce shadows of many different lengths.

7. Fried Film

The Claim: In the Sun, the Moon's temperature is toasty 280 degrees F. The film (among other things) would have melted.

The Science: No one was leaving bare film out on the hot lunar surface. All material was contained in protective canisters. In addition, at the time the Apollo missions landed, they were either at lunar dawn or dusk. As a result, the temperature was more easily manageable.

The Claim: To leave a footprint requires moisture in the soil, doesn't it?

The Science: Not always. If you take some dry fine-grained dust such as talcum powder and dump it out, it's easy to make tracks in it that hold their shape. The particles hold their positions due to the friction between them.

The Claim: Space is filled with super-fast micro meteors that would punch through the ship and kill the astronauts.

The Science: Space is really amazingly big. While there are indeed an uncountable number of tiny pieces of debris travelling through the Solar System at speeds in the neighborhood of 120,000MPH, the volume of space keeps the density low. The chance of any given cubic yard of space having a micro-meteor passing through it is incredibly close to zero. Additionally, the astronauts suits included a layer of kevlar to protect them from any tiny fragment they might encounter.

The Claim: When the Lunar Excursion Module (LEM) landed, its powerful engine didn't burrow a deep crater in the "dusty surface."

The Science: Beneath the layer of dust, the Moon is made of fairly densely-packed rock. What dust and loose dirt there was though, was "kicked up" as referenced by the astronauts and captured in their landing films.

The Claim: How come in that one video of the LEM leaving the surface, the camera follows it up into the sky? Who was running that camera?

The Science: Though we are sure the photographer, Ed Fendell, would have loved to have been on the lunar surface instead of at his seat in Mission Control, he indeed was in Houston remotely controlling a television camera on the lunar rover (which was left on the surface).

The Claim: There's no way that big moon buggy they were driving could have fit into that little landing module!

The Science: The rover was very cleverly constructed to be made out of very light materials, and designed to fold up to about the size of a large suitcase.

The Claim: Space is littered with little points of lights (stars). Why then are they missing from the photographs?

The Science: If you've ever taken a photograph outside at night, you'll notice that faint distant objects don't show up. That's not because the air blocks them -- it's because the brightness of the nearby objects washes out the film. In fact if you were standing on the day side of the Moon, you'd have to somehow block the landscape out in order for your eyes to adapt enough to pick out the stars.