41SHOT

Preface

I wrote most of the article below some years ago when the Moon landing conspiracy theory was still circulating more widely. As an engineer, it was one of those things that really bothered me because so many people were willing to write off such an enormous technological achievement as an elaborate hoax - based on flawed arguments presented by a handful of people who did not have the expertise to make such claims.

These days, it doesn’t bother me as much and people appear to have largely moved on to new conspiracy theories. If someone does happen to bring it up, I’ll simply give them a link to the article and get on with my day.

The following is a slightly edited revision of the original article, which I hope will still be helpful or interesting to some people.

An XKCD cartoon satirising conspiracy theories (click here for full size)

Introduction

If you’re reading this, I’m going to assume that you saw the Fox TV show that claims that the Moon Landings were faked, or are familiar with the opinions presented during the show. While I would like to convince those that were swayed by the opinions that twelve men have walked on the Moon since 1969^[a], I understand beliefs can be extremely difficult to change by logical reasoning alone. What I do intend to achieve, is to demonstrate that the Moon Landing conspiracy theory is based on incorrect assertions and pseudoscience.

To this end, I will provide explanations for the lack of validity of most of the claims commonly cited by the conspiracy theorists. These explanations are backed-up by real science that the reader can verify by using the cited sources or performing their own research.

There are no stars in the photos

This is almost always the first argument put forward by the conspiracy theorists. Probably because it invokes a strong reaction of surprise in the intended victim, “Hey, that’s really obvious now that you’ve pointed that out to me, I wonder why I didn’t notice that before. You may be on to something”. It also seems be a legitimate point, because we can see stars when we look up at the moon at night.

Unfortunately for the conspiracy theorist, this is also one of the easiest to debunk.

Point #1: Cameras do not work the same as our eyes. Human eyes have a dynamic range that is well beyond the capabilities of any modern film or digital camera^[1],[2]. This means that our eyes can perceive much greater ranges of light intensity in the same scene than cameras can.

Point #2: Star-light is several orders of magnitude less intense than sunlight reflected off the lunar surface. For example, a full Moon is around 30,000 times brighter than the brightest star (except for the Sun), as seen from Earth^[3]. Subjectively, this difference is not as exaggerated because our eyes have a power-law response to light intensity^[4]. Film and camera sensors have a much more linear response to light, so relative magnitudes are important.

Put simply, there is not enough light from distant stars to show up in a photograph where the camera has been set to properly expose details of the lunar landscape on film. The astronauts could have taken a photo with stars in the background, but the foreground would have appeared completely white with no visible detail. If overexposed photos such as this existed, they are unlikely to have been published.

Don’t take my word for it though. Pick-up any camera with manual exposure controls and set it to correctly expose a full Moon at night (i.e. details on the Moon’s surface are visible in shades of grey). In my experience this is approximately 1000^th of a second at F/5.6 with ISO-200 sensitivity. Now take a photo of the Moon and look at the resulting image. You will not see any stars in the photo.

Another way to simulate this is to take your camera to a beach on a bright, sunny day. Take a correctly exposed photograph of the sand and record the exposure settings. Wait until dark and take a photo of the night sky with the same settings. Again, there will be no stars visible in the recorded image.

Take a look at any photograph from any space mission where the foreground object (space shuttle, satellite, astronaut, space station, etc.) is lit directly by the Sun and notice how the background appears completely black. There are no stars. Surely these are not all fakes too?

The irony is that if stars were in fact visible in the photos, then there would be a genuine reason to doubt their authenticity.

NASA photo of ISS above Earth shows no stars

The flag is waving

Yes it is, but only during the time that an astronaut is in physical contact with the flag or flag-pole, and for several seconds afterward. Other than those occasions, the flags are all completely still at any time that they are visible in the many hours of video footage taken over the course of the six missions. A lot of this footage is freely available on the Internet; feel free to have a look for yourself.

There is no valid reason to think that a flag cannot wave in vacuum. Any kinetic energy applied to the flag or flag-pole will cause the flag to oscillate until the energy has dissipated. On Earth, this oscillation would be damped very quickly by the air around the flag and the flag would stop waving within a couple of seconds after the energy source had been removed (assuming the air is still). On the Moon, there is no air to dampen the oscillation, so the flag takes a few more seconds to stop waving.

For an excellent visual comparison of a flag waving in air and in a vacuum, see the Myth Busters video clip where this is demonstrated inside a vacuum chamber^[5].

There are no flames visible when the lunar module lifts off from the surface

This statement is correct, but does not imply that the footage was faked.

The rockets on both the ascent and descent stages of the Apollo Lunar Module used an Aerozine 50 fuel and dinitrogen tetroxide (N₂O₄) as an oxidiser^[6]. Aerozine 50 is a 50:50 mix of hydrazine and unsymmetrical dimethylhydrazine. It was developed in the late 1950s as a fuel for ICBM rocket motors and is still used today for spacecraft propulsion^[7].

When Aerozine and N₂O₄ react, they produce no visible flame. This is in contrast to the Apollo launches from Earth where RP-1 fuel was used in the first stage of the Saturn V rocket, which did produce visible flames and smoke.

The blast crater isn’t big enough

I can’t really improve on Phil Plait’s explanation of this (other than adding some metric unit conversions), so I’ll quote him here:

“When someone driving a car pulls into a parking spot, do they do it at 100 kilometers per hour? Of course not. They slow down first, easing off the accelerator. The astronauts did the same thing. Sure, the rocket on the lander was capable of 10,000 pounds[44 000 N] of thrust, but they had a throttle. They fired the rocket hard to deorbit and slow enough to land on the Moon, but they didn't need to thrust that hard as they approached the lunar surface; they throttled down to about 3000 pounds [3 000 N]of thrust.

Now here comes a little bit of math: the engine nozzle was about 54 inches across (from the Encyclopaedia Astronautica), which means it had an area of 2300 square inches [1.5 m²]. That in turn means that the thrust generated a pressure of only about 1.5 pounds per square inch [10 kPa]! That's not a lot of pressure. Moreover, in a vacuum, the exhaust from a rocket spreads out very rapidly. On Earth, the air in our atmosphere constrains the thrust of a rocket into a narrow column, which is why you get long flames and columns of smoke from the back of a rocket. In a vacuum, no air means the exhaust spreads out even more, lowering the pressure. That's why there's no blast crater! Three thousand pounds of thrust sounds like a lot, but it was so spread out it was actually rather gentle.”^[8]

I recommend visiting Phil’s “Bad Astronomy” website for his many other explanations of claims made by Moon landing conspiracy theorists.

Radiation from the Van Allen belt would have killed the astronauts

The people making this claim are never cosmic radiation specialists, but the Soviet and American scientists involved in the Sputnik 3, Explorer 4, Pioneer 3, and Luna 1 missions were. These were unmanned probes and satellites, launched in 1958 and 1959 (10 years before Apollo 11), specifically designed to study and measure the radiation present in the Van Allen belt^[9].

Based on the data from these missions, both the Soviets and the Americans concluded that the Van Allen belt would not be significantly hazardous to humans travelling beyond Earth’s orbit (provided that they passed through it reasonably quickly). The Van Allen belt is made up of energetic charged particles that are help in place by the Earth’s magnetic field. These do have a strong ionising effect, but have very low penetration through matter (most are absorbed by the skin of a spacecraft) at the energy levels present in the radiation belt^[10]. This can be contrast to other types of ionizing radiation such as x-rays and gamma rays, which can pass through a more significant amount of matter.

If the American government had lied about the measurements they had taken from the Van Allen belt in order to support their hoax, then surely the Soviet government would have exposed the truth?

This claim has no validity other than it was a risk that was thoroughly assessed by both nations involved in the space-race, long before the first manned mission outside of low Earth orbit.

Contour chart showing normal proton flux for energy ≥ 100 keV

They didn’t have the necessary technology to go to the Moon in 1969

Again, this assertion is usually put forward by non-experts. The question to ask is, “do you know of any specific technical requirement of the Apollo 11 mission that was not able to be met in the 1960s?”

The conspiracy theorists are usually referring to computational technology when they mention this one, so let’s focus in on that.

The Apollo Guidance Computer (AGC) was the first computer to employ Integrated Circuits (ICs). The earliest version contained 4100 ICs, which were manufactured by Fairchild Semiconductor^[11]. It used an accumulator-based architecture, which is still used in modern microcontrollers (e.g. PICmicro)^[12]. It ran on a 2 MHz crystal clock, and had 4KB of memory.

That may not be much compared to our high-powered computers of today, but there’s nothing to suggest that it wasn’t up to the task. In fact, this computer was used for the experimental fly-by-wire system in the F8 Crusader^[13], so it couldn’t have been that bad!

There wasn’t enough time to gain the expertise needed for the 1969 landing

This sort of goes hand-in-hand with the technology argument, but deserves its own section. Even someone who doesn’t dispute the landings would probably agree that going from the start of the space-race in 1957 to a manned Moon landing in 1969 would surely have been close to impossible.

Although it an extremely challenging task, there were no “giant leaps” in knowledge that occurred for the convenience of a hoax. Incremental steps were taken to address each challenge, right from determining whether humans could even survive in a zero-gravity environment, up to successfully performing EVAs, rendezvous, docking, orbital transfers and lander module maneuvering.

The Discovery Channel has a good TV series called “When we left Earth”, that covers the Mercury and Gemini projects that led up to the Apollo programme, and the pre-landing Apollo missions that paved the way for Apollo 11. They go through each of the major challenges that were identified and how they were overcome, with a lot of nice video footage. The series then follows on from the Moon landings to SkyLab, then on to the Space Shuttle era. It becomes clear how all the pieces of the puzzle fit together. If the moon landings were faked because knowledge gaps existed that prevented real landings, then further space exploration would probably not have been possible until much later due to those same gaps.

First Earth-rise to be witnessed by mankind, during Apollo 8 mission

There were various photographic ‘abnormalities’

The ones that seem to be commonly cited are: The shadows aren’t dark enough, there appear to be multiple light sources, part of the camera cross-hairs are missing, the background is identical on shots taken in different locations, the pictures are too perfect, etc.

A few points to address these issues:

The Moon is an effective light source^[14] due to its highly reflective surface. Look up at a full Moon (even in the daytime) and see for yourself. Photographers often use reflected light to soften shadowed areas and the same thing happens on the Moon (even if it was not the intention of the person taking the photograph). And don’t forget that reflected light can also create its own shadows. In summary, there are multiple light sources (there’s nothing wrong with that) and the shadows do not have to be pure black.

When taking photos in high-contrast conditions (e.g. under direct sunlight), you will often find that some areas (especially white surfaces) are over-exposed when attempting to preserve detail in darker areas of the scene. In extreme cases, this leads to highlighted areas ‘bleeding’ into adjacent areas of the photograph. This occurs in digital and film photography, and is caused by an overflow of charge into neighbouring photodetectors^[15] (digital) or AgBr grains^[16] (film). That is why the camera cross-hairs sometimes appear to be ‘behind’ objects in the photo. They are not behind anything, they have been blown out by over-exposed highlights. Look carefully at the photos mentioned, and you will see in all cases where part of the cross-hair is not visible, the object it falls over is pure white with no visible detail (a clear sign of over-exposure). Although sunlight is not as harsh on Earth as it is on the Moon (thanks to our atmosphere), this anomaly can still be demonstrated fairly easily with almost any camera.

On Earth, our brains can judge how far away a landscape feature is, based on our familiarity with that type of feature (or objects near it) and the atmospheric hazing effect (distant features lose contrast and sharpness). On the Moon, we lose this ability because the landscape is unfamiliar and there is no atmosphere. Therefore, we can easily mistake a large mountain 10km away for small hill 100m away (especially in a photo). The mountain shown in two of the photos that the conspiracy theorists attempt to trick us with is Mons Hadley Delta^[17], which is 3.5km high (the highest mountain in New Zealand is 3.7km by comparison^[18]) and 11km SSE of the Apollo 15 LM (featured in the foreground); not a small nearby hill as they would have us believe^[b]. I’ll explain in the following paragraph why this matters.

If you take a photo that is composed of some subject matter in the foreground, and a mountain some significant distance away, and you take another photo from a short distance away (say, 200m) from the first location (but facing the same mountain), the backgrounds in the photos will look almost identical even though the foregrounds have completely changed. This is called parallax^[19], which is trigonometry, not trickery. So yes, there are some photos with very similar backgrounds, but there’s no reason for NASA to apologise for this and certainly not a justification for suggesting that they were faked.

Finally, take a look at any publication that features photos of an historic event. Do see you nasty, blurred photos taken at an odd angle, where the subject is partially cut-off from the frame? Not usually I would imagine. That is because only the best of a collection of photos are published, and this usually represents a very small proportion of the total photos taken. Nobody wants to look at hundreds of crappy photos. Even though the astronauts were thoroughly trained in the use of their suit-mounted cameras, there were probably plenty of photographs that went straight into the bin. If you take the time to view some of the more ‘boring’ video clips of Apollo missions, you will see the astronauts posing many times for the same shot, trying different angles, etc. The photos look good because we’ve only ever seen the good ones!

There are other claims that the conspiracy theorists make about ‘abnormalities’ in the photographs, but these are explained much better when compared to studio mock-ups of the scenes in question. There are some who have gone to the trouble of doing this, most notably Ian Williams Goddard of Goddard’s Journal^[20], as well as Jamie Hyneman and Adam Savage of MythBusters^[21]. I suggest having a look at their work if you are still interested in the photographic aspects of the conspiracy theory.

Final thoughts

Finally, let’s look at how this all got started. Although this conspiracy theory has been around for several decades, it seems to have achieved most of its recent popularity as a result of a FOX TV show, aired in 2001^[22]. The show was written and directed by John Moffet. You probably don’t know who John Moffet is (neither did I), so I’ll fill you in on his other achievements. A year earlier, he wrote a TV show called “World’s Scariest Ghosts: Caught on Tape”. In 2002 (and what must surely have been a low-point of his career), he directed a show called “Rods!”, in which he collected some footage of insects flying past video cameras operating at low shutter speeds and tried to convince us that they were giant UFOs, flying at extremely high speeds and invisible to the naked eye^[23]. More recently he co-produced the shows, “Destroyed in Seconds” and “The Superstars”^[24].

The “expert” interviewed in this show was William Kaysing, a former employee of a company that developed rocket engines for NASA. He was employed as a writer and librarian in the Technical Publications department from 1957 to 1963^[25]. His academic qualifications consisted of a Bachelor of Arts in English, from the University of Southern California. He was not an engineer and certainly not in a position to know NASA’s innermost secrets. In 1974 he self-published a book in which he claimed that the Moon landings were faked. In 1997, he attempted to sue a former astronaut for calling his ideas “wacky”.

So, here we have a writer/director/producer with a track-record for creating sensationalist TV shows and a writer/librarian trying to sell more copies of his book. Is it reasonable to believe that the approximately 400 000 people^[25] who worked on the Apollo missions are all lying, and that these two guys are telling the truth? The answer seems quite obvious to me, but I’ll leave you to decide.

Apollo 11 mission insignia

Footnotes

(a) Astronauts that have walked on the moon

20 Jul 1969	Neil Armstrong, Edwin "Buzz" Aldrin
19 Nov 1969	Charles (Pete) Conrad, Alan Bean
05 Feb 1971	Alan Shepard, Edgar Mitchell
30 Jul 1971	James Irwin, David Scott
21-23 Apr 1972	Charles Duke, John Young
11-13 Dec 1972	Harrison Schmitt, Eugene Cernan