Republished July 20, 2009--Forty 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 photographic evidence, and find out why experts say some of the most common claims simply don't hold water.

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.

The fact of the matter 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 spaceflight historian Roger Launius, of the Smithsonian's National Air and Space Museum in Washington D.C.

The astronauts also accidentally bent the horizontal rods holding the flag in place several times, creating the appearance of a rippling flag in photographs (Apollo 11 moon-landing pictures).

--Ker Than