"My God, it's full of stars!" Arthur C. Clarke's 2001
character Dave Bowman famously exclaimed when faced with the vastness of space.
You can tell Apollo was faked because ...
the astronauts made no such exclamation while on the moon, and the black backgrounds of their photographs are curiously devoid of stars. (See more iconic space pictures
The fact of the matter is ...
the moon's surface reflects sunlight, and that glare would have made stars difficult to see. Also, the astronauts photographed their lunar adventures using fast exposure settings, which would have limited incoming background light.
"They were taking pictures at 1/150th or 1/250th of a second," Bad Astronomy's Plait said. "In that amount of time, stars just don't show up."
(Related: Hear a 1969 audio history of the space age
, including the Apollo 11 moon landing.)
Photograph courtesy NASA