Almost 50 years after U.S. astronaut Neil Armstrong became the first human to set foot on the moon, many conspiracy theorists still insist the Apollo 11 moon landing was an elaborate hoax.
Examine the evidence, and find out why experts say the most common claims simply don't hold water.
1. THE SOIL DOESN’T MOVE
You can tell Apollo 11 was faked because: the module is shown sitting on relatively flat, undisturbed soil. According to sceptics, the lander's descent should have been accompanied by a large dust cloud and would have formed a noticeable crater.
This truth is: the Apollo 11 lander's engines were throttled back just before landing, and it did not hover long enough to form a crater or kick up much dust, the Smithsonian spaceflight historian Roger Launius said.
"Science fiction movies depict this big jet of fire coming out as [spacecraft] land, but that's not how they did it on the moon," he added. "That's not the way they would do it now or anytime in the future."
2. THE FLAPPING FLAG
You can tell Apollo 11 was faked because: the American flag appears to be flapping as if "in a breeze" in videos and photographs supposedly taken from the airless lunar surface.
This truth is: "the video you see where the flag's moving is because the astronaut just placed it there, and the inertia from when they let go kept it moving," said Launius.
The astronauts also accidentally bent the horizontal rods holding the flag in place several times, creating the appearance of a rippling flag in photographs
3. PHOTOGRAPHS BUT NO CAMERAS
You can tell Apollo 11 was faked because: only two astronauts walked on the moon at a time, yet in photographs such as this one where both are visible, there is no sign of a camera. So who took the picture?
This truth is: the cameras were mounted to the astronauts' chests, said astronomer Phil Plait, author of the award-winning blog Bad Astronomy and president of the James Randi Educational Foundation.
Plait notes, "you can see [Neil's] arms are sort of at his chest. That's where the camera is. He wasn't holding it up to his visor."
4. STRANGE SHADOWS
You can tell Apollo 11 was faked because: Aldrin is seen in the shadow of the lander, yet he is clearly visible. Hoax subscribers say that many shadows look strange in Apollo 11 pictures. Some shadows don't appear to be parallel with each other, and some objects in shadow appear well lit, hinting that light was coming from multiple sources—suspiciously like studio cameras.
This truth is: there were multiple light sources, Launius said. "You've got the sun, the Earth's reflected light, light reflecting off the lunar module, the spacesuits, and also the lunar surface."
It's also important to note that the lunar surface is not flat, he added. "If an object is in a dip, you're going to get a different shadow compared to an object next to it that is on a level surface."
5. CLEAR PRINTS
You can tell Apollo 11 was faked because: the astronauts' prints are a bit too clear for being made on a bone-dry world. Prints that well defined could only have been made in wet sand.
This truth is: that's nonsense, said Bad Astronomy's Plait. Moondust, or regolith, is "like a finely ground powder. When you look at it under a microscope, it almost looks like volcanic ash. So when you step on it, it can compress very easily into the shape of a boot." And those shapes could stay pristine for a long while thanks to the airless vacuum on the moon.
You can tell Apollo 11 was faked because: those mysterious reflections come from studio lights on a production set.
This truth is: it’s highly unlikely NASA would make such an obvious blunder if they had spent millions of dollars to fake the Apollo 11 moon landing, Plait said.
"Okay, let's take a step back. NASA's going to release a picture showing studio lights? Hello!" The odd lights in the picture are simply lens flares," he said. "There's a big fat pentagonal one right in the middle that is from the aperture of the camera itself."