NASA: STILL FROM 16MM AUTOMATIC MOTION PICTURE CAMERA. ANNOTATION ADDED BY UNKNOWN THIRD PARTY.

Note A: One astronaut casts a significantly longer shadow than the other. This could only happen if they were being lit by a nearby light source, or possibly from different light sources. Since the sun is the only significant source of light on the lunar surface, their shadows should be equally long. [David Percy]

We can reject the multiple light source theory without too much difficulty. Notice that the astronauts are closely in line with each other with respect to the light source. A light set to illuminate one could hardly avoid also illuminating the other. This would cause each astronaut to cast two shadows, one from each light source.

A very close light source would also cast shadows of different length, but not as shown. As the picture below shows, the longer shadow would be cast by the astronaut farthest from the light. In the photo in question, the near astronaut casts the longest shadow.

Much of conspiracist photographer/filmmaker David Percy's argument is based on lengths and directions of shadows cast in photographs. His argument in this case and many others presumes a flat level surface upon which to cast shadows. The foreground of the image is darker than the background, indicating that the terrain is not at all level. The ground slopes downhill away from the camera to roughly the center of the image, then begins to slope upward again and receives more direct sunlight.

CLAVIUS

CLAVIUS

With 3D graphics we can see the behavior of objects casting shadows onto variously sloping surfaces. In the rendering on the left the two cylinders are exactly the same height, but are on different sides of a shallow depression. The light source shines at a low angle from some distance away.

The rendering on the right is from directly overhead and shows clearly that the shadow cast by the cylinder on the "downhill" side is distinctly longer than the other shadow. Note also that the ground exhibits exactly the same kind of variable lighting that we see in the photograph, helping confirm that this (not some mysterious extra light source) is the phenomenon at work, although we note that the variation might also be caused by the astronauts churning up darker subsurface soil.

Other frames from the same film show the astronauts casting shadows of equal length as they move about. They are obviously moving toward and away from a large light source. [David Percy]

AULIS PUBLISHING, FROM NASA

Again Percy relies heavily on his presumption that the ground is essentially flat. The shadow of someone walking around on rough terrain would also lengthen or shorten. A low sun elevation would greatly amplify such differences in shadow length.

In this case, we look at the photo at the top of the page and consider that the astronaut on the right is standing atop a small rise and the astronaut on the right is at a lower elevation, casting his shadow on roughly level ground.

In the second photo we consider that one astronaut has stepped back while the other one has gone some distance away, probably to take photographs. He is no longer on the small rise and is now also casting a shadow onto relatively level ground.

Percy's argument that the shadow lengths are caused by variations in illumination angles due to a nearby (versus infinitely distant) light source would also require the shadows to diverge slightly in the second photgraph. But we observe the shadows to be virtually parallel, converging slightly due to the perspective we would expect from such a camera angle. But if Percy is correct, the distant astronaut's shadow should point farther away; the shadows should appear to diverge.

Photos of the area show it to be flat. [David Percy]

AULIS PUBLISHING, FROM NASA AS11-40-5905

Percy presents the photograph on the right. His argument appears to be, "It's flat because it looks flat to me." The horizon isn't flat, but that's anywhere from a hundred feet to five miles away from the area we're interested in. (Distances were very hard to judge on the moon, and are impossible to judge from single still photos.)

The question to ask is whether we'd see any evidence variation if it really were there. What would be sufficient evidence of terrain variation? We might expect to see variations in the lighting. Terrain less directly lit might appear darker, as we noted above. We might also look for hard-edged discontinuities that represent the crests of rises. We might also look for objects that disappear abruptly as if behind rises. We might also look for shadows that behave a bit differently than expected.

Observing some or all of these would suggest a variation in terrain. But would failing to observe them prove that the terrain was flat? No. In logic this is called the fallacy of inverse implication, encapsulated by the maxim, "Absence of evidence is not evidence of absence." Just because Percy fails to observe our expected indicators of slope doesn't mean no such slope exists. There are cases in which the slope exists without leaving indicators.

The general problem of contour extrapolation in these still photos is covered here. For this specific photo, we note little color variation, no hard-edged discontinuities. It's unclear whether the flag pole disappears behind a rise or simply into the soil.

NASA: AS11-40-5873

The shadow in the foreground is cast by the solar wind collector. As shown, the collector is simply a rectangular sheet of material hung on a pole to collect particles from the solar wind. The shadow shows it was correctly deployed facing the sun as directly as possible.

Correctly aligned, the rectangular top should cast a nearly-perfect rectangular shadow. But in Percy's proof photo we see the tip of the collector's shadow become gradually thinner, as if it were falling on a patch of ground sloping away from the camera.

The strongest evidence, however, of irregular terrain is the shadow of the flag and flagpole. They are mostly invisible in Percy's version of the photo, but we can examine it more closely in a larger image.

NASA: AS11-40-5873, ANNOTATIONS ADDED

The white line represents a theoretical straight line that would be the shadow cast by a perfectly straight flagpole. But it is plain that the shadow is not perfectly straight. Since Percy cannot argue that the object casting the shadow is curved, nor can this effect be produced by artificial light sources, we have no choice but to conclude that the surface onto which this shadow is being cast is not planar.

The evidence Percy presents to establish a planar surface is ironically the best evidence of a non-planar surface. A significant change in the angle of the lunar surface can be found in the area onto which the shadows in question are being cast. In fact, the flagpole shadow very closely resembles the theoretical model explored above in our computer renderings. When viewed from a high angle (e.g., the lunar module cockpit) shadows cast onto non-planar terrain vary in length, but not necessarily in shape. Linear objects cast linear shadows. But when viewed from a low angle, such shadows display a change in shape or direction, such as we see in the proof photo. Linear objects can cast curved or bent shadows.

The irregularity in the terrain corresponds exactly to the location in which the variations in shadow length are observed. We further note that the flagpole shadow cannot be produced by any of the hoax methods Percy has suggested, and in fact can only be produced by a lunar surface irregularity. This obvious irregularity has the shape and orientation that would produce the shadows observed in the photo in question.