a short distance down, because the heat can’t flow well below that depth. Below that depth, the rock is eternally freezing cold, insulated by the dust and rock above it. The dust cools rapidly once the Sun sets. During a lunar eclipse, when the Moon is in the Earth’s shadow, the lunar temperature has been measured to drop very quickly. The dust gets as cold as the rock beneath it.
That coldness came back to haunt one astronaut. During an excursion, Apollo 16 astronaut John Young realized that the rocks they had collected were all rather small. He wanted one really big one to impress the scientists back home. He grabbed a rock weighing roughly a kilogram (two pounds), and placed it underneath the lander, in shadow, while he closed up shop to prepare for the return to Earth. When he was done, he put the rock on the LM and repressurized the module.
It was then that Young realized he needed to rearrange the rocks a bit to balance them in the LM, making sure that the spacecraft wouldn’t tilt dangerously during takeoff due to an imbalance in the mass distribution that the automatic controls couldn’t handle. He had already taken his gloves off, and when he grabbed the big rock, he got a surprise: the rock had been in the shadow long enough to dump its extra heat, and had become bitterly cold! Young was actually lucky not to get frostbite. When Young retold this story to Paul Lowman, a NASA geologist and lunar expert, Lowman exclaimed, “This is the only time I’ve ever heard somebody describe the actual temperature of the Moon as he actually felt it!”
Hoax-proponents also claim that the film carried by the astronauts would have melted in the tremendous lunar heat. In reality, the opposite problem is true: they didn’t have to worry about film melting; they had to insulate it to keep it from freezing.
Another common line of “proof” of a NASA conspiracy has to do with the play of light and shadows on the Moon. The most common of these claims concerns the blackness of the shadows. If the Sun is the only source of light, say the hoax-believers, then shadows should be absolutely black because there is no scattered sunlight from the air to fill them in. Without any light illuminating the ground in the shadow, it should be completely, utterly black.
On the Earth, we are accustomed to shadows that are not actually totally black. This is due primarily to our bright sky. The Sun itself casts a sharp shadow, but the light from the air in the sky illuminates the ground in our shadow, making us able to see objects there.
On the Moon, where the sky is black, conspiracy theorists claim the lunar surface inside the shadow should be completely black. If the Sun is the only source of light, they say, the shadows should be black as pitch. Yet, in the astronaut photographs we commonly see shadows filled in a bit, as if there were another source of light. Obviously, to the hoax-proponents, since the Apollo photographs were taken on a soundstage on Earth, the source of this light is the air inside the building, scattering the light from a spotlight.
However (stop me if you’ve heard this before), they’re wrong. There
Interestingly, sometimes the shadows falling on the lunar surface appear to be filled in as well. Ironically, the source of light is most likely the astronauts themselves. The spacesuits and the LM are brightly lit by the Sun and the lunar surface, and that light is reflected back onto the lunar surface, filling in the shadows a bit. This exact same technique is used by photographers and cameramen, who employ umbrella-like reflectors to fill in the shadows when photographing a scene.
However, if you look more closely at the photographs, the problem does get more complicated. In what has become the most famous picture taken on the Moon, Neil Armstrong snapped an image of Buzz Aldrin standing near the LM during the Apollo 11 mission. We see Buzz facing the camera, lit by the Sun from behind and to the right. Reflected in his helmet we can see Neil’s image as well as the lander leg and various shadows.
One of the most famous photographs from the Apollo missions, the “Man on the Moon” picture of Buzz Aldrin. Conspiracy theorists point to many clues that indicate the image was faked: the lack of stars, the filled-in shadows, and the apparent spotlight effect. However, all of this is in fact evidence that the picture is genuine. Note also Aldrin’s knees; they are covered with ash-gray lunar surface powder from the many times Buzz had to dip down to pick up a dropped tool or collect a rock sample. Despite what others might say, this image was indeed taken on the surface of an alien body, the Earth’s Moon.
This image is of paramount importance to the hoax-believers. It embodies two claims critical to their arguments: From the way the ground is illuminated Aldrin is clearly being lit by a spotlight aimed directly at him, and from shadows in his visor it looks as if that spotlight is nearby.
This picture is oddly lighted, but not because of any human trickery. Actually, the spot of light results from a peculiar property of the lunar surface: it tends to reflect light back in the direction from which it comes. This is called backscatter, and it is very strong on the Moon. If you were to shine a flashlight in front of you there, you’d see the light strongly reflected back to you. However, someone standing off to the side would see hardly any reflected light at all. Actually, you’ve almost certainly seen this effect on your own.
You might guess that the half-full Moon is half as bright as the full Moon, but that’s not correct. The full Moon is roughly
That’s why Aldrin appears to be in a spotlight. In the area where he’s standing, the light is reflected straight toward Armstrong’s camera. Farther away from Aldrin, though, the light gets reflected
The technical name for this glow is heiligenschein, which is German for “halo.” You can see it yourself on a dewy morning. Face away from the Sun so that the shadow of your head falls on some wet grass. You can see the glow of backscattered sunlight surrounding your shadow’s head, looking very much like a halo. You can also do this where the ground is dusty, such as in a baseball diamond infield. The effect can be very striking. This “spotlight” effect can be seen in many Apollo photographs, but only when the astronaut taking the picture had his back to the Sun, just as you’d expect. There’s no spotlight, just some odd — but natural — physics at work.
Incidentally, the opposite effect happens when you drive a car on a rainy night. Wet pavement reflects the light
The second claim about the photograph deals with the shadows. If you look in Aldrin’s visor, you’ll see that the shadows aren’t parallel. If the Sun is the source of light, all the shadows should be parallel. Instead, they point in different directions, which means the source of light must be close by. Ergo: it’s a spotlight.
Well, we’ve already seen it’s not a spotlight, so we know it must be the Sun. Actually, this claim is another ridiculously easy one to refute. We see the shadows reflected in a
However, there are also some images that are not visor reflections, but still seem to have shadows pointing in different directions. Again, if the Sun is the only source of light, shadows should be linear and parallel. Clearly, sometimes they are not parallel. To the conspiracy theorists, of course, this is more evidence that the images are fake.
