Four facts that prove we put men on the Moon

Moon conspiracy theories have existed since pretty much the day after humanity first landed on the Moon. The origins are hard to trace (I recommend this Forbes article Where did the moon landing conspiracy theory come from?) but needless to say, working in the space industry, the most common question I get asked is:

How can you be sure we went to the Moon?

Well science teaches us to be skeptical so of course it is difficult to be 100% sure of anything. However, what I can be sure of is that the arguments for the Moon landings occurring are much more stronger than the arguments against them.

There are countless sections of the conspiracy to choose from but here are 4 of my favourite reasons which prove that we did in fact go the Moon in July of 1969.

A mirror left on the Moon's surface during Apollo 11. Credit: NASA.

1. There's a mirror on the Moon

The Apollo 11 astronauts, Buzz Aldrin and Neil Armstrong, left a small mirror on the Moon (pictured). It's possible, with a very powerful laser, like that of the McDonald Laser ranging station at Fort Davis in Texas, to bounce a signal off this mirror from Earth. In fact, this was routinely done for the 40 years this experiment was on-going until it was ultimately cancelled in 2009.

For those who know basic physics, distance = speed x time. We know the speed of light, and we can measure the time taken to send and receive a laser signal from this mirror. This gives the expected distance to the moon - around 385,000km which matches with our expectations form orbital mechanics.

2. You can SEE the evidence

The image below was captured by the Lunar Reconnaissance Orbiter (LRO), which has been orbiting the Moon since 2009.

Apollo 17 landing site captured by the Lunar Reconnaissance Orbiter (LRO). Credit: NASA.

The image, released in 2011 by NASA, clearly shows evidence of human activity on the lunar surface. They say "you have to see it to believe it". Unfortunately, conspiracy theorists tend to reject this motto and claim that no satellites exist in lunar orbit and that these photos are all the product of CGI (computer generated image) technologies.

3. The physics of dust

This is my favourite proof as it such an elegant and simple proof, which cannot have been faked in the Apollo era. You can also perform this proof and see for yourself.

So how can a bit of dust prove we went to the Moon? Read on!

It is possible to use a computer to analyse videos of the Lunar Roving Vehicle, pictured below, to track the lunar dust being kicked up off the surface.

'The last man on the moon', Eugene Cernan, Commander of Apollo 17 drives the Lunar Roving Vehicle, 1972. Credit: NASA.

If you track the packets of dust as they float back down the surface of the Moon you can figure out two fundamental things pretty easily.

1. The dust is traces a perfect parabola.

So what? Well, basic Newtonian mechanics say that this can only happen in the absence of friction - meaning there is no atmosphere wherever these dust particles are being filmed. For a brush-up on projectile motion visit here.

This means if this video was created in a studio it would have to have been done inside a giant vacuum chamber. The largest vacuum chamber in the world, which was actually built in 1969, is NASA’s Space Power Facility which is an impressive 30m cylinder standing 37m tall - but that’s not large enough to fake the Apollo landings with its large rolling hills, continuous long shots and the range of the LRV. Besides, the logistics of filming the world’s biggest hoax in a vacuum chamber would have been horrifically complicated - perhaps going to the Moon for real is just as difficult.

2. From dust you can calculate gravity.

This second, and more interesting piece of data you can gain from this analysis of dusty parabolas is the estimated gravitational force experienced by the particles. You can do this yourself, here’s the first one I pulled off the Google: The Acceleration of Moon Dust.

Now, from the known scale and velocity of the rover you can fit an acceleration co-efficient (this is high school level physics, any serious Apollo conspiracy theorist can do this if they so wish). If you want definitive proof you should do it yourself and you’ll find you’ll get something very close to the accepted value of acceleration on the Moon: 1.625 m/s^2.

This is impossible to fake.

Ok, not impossible, but the only ways you could fake this are:

a. with CGI, which was infeasible in the 1969–72 era,

b. by doctoring the speed of the video, but as the quoted article points out, the camera shake is huge. You’re telling me NASA already pumped the air out of the studio and made fully operational spacesuits for this but they didn’t bother to invest in a camera stabilizer? That’s just sloppy hoax work.

c. by doctoring the scale of the rover and make it appear larger by employing tiny humans (they'd have to be less than 0.5m tall for the maths to work out) in order to reduce the perceived gravitational acceleration from Earth's value of 9.81m/s² to the Moon's measly 1.62 m/s².

Otherwise, to truly experience this gravitational force you are either on the moon or in a giant dusty orbiting laboratory that looks like the Moon which is being accurately spun at an appropriate rate so as to create artificial lunar gravity - the former being far more plausible than the latter here.

This is unshakable, definitive proof that the Apollo landings could not have been faked even if NASA had wanted too.

4. Russia

I’ve neglected the million other myriad reasons that are just as convincing but less technical. My favourite being this: the US was in a cold war space race with the USSR, and they were really trying to “one-up” each other for many years. If there was any clue, any clue at all, that the US faked it, why did the Russians not call BS? The idea of Russia and America partnering to cover up an Apollo hoax is more laughable than the conspiracy theories themselves.

Cold war propaganda. Credit: CNN.

And there you have it, four great reasons that prove we did indeed go to the Moon! If I missed any great Apollo conspiracy theories then please leave a comment and don't forget to subscribe for more awesome space posts. If you liked this article then please share on your favourite site!