Thursday, 21 March 2013

Apollo 11 Moon landings.

It is claimed that on July 20th 1969 Neil Armstrong and then Buzz Aldrin were the first people in humanity to walk on the moon. If you type 'moon landings' into Google, 10 results leap up on the first page of search results, 7 of  which have some relation to the words fake or hoax. Lets be honest, lots of people believe the moon landings were faked and it's one conspiracy theory that seems coherent, there was every political motive to fake them. I decided to investigate the moon landings 'can of worms' and in order to make a reasonable decision about whether they were faked or not I had to go on a journey of physics myself. Also I had to find independent/third party evidence to attempt to prove that Apollo 11 went to the  moon.

 
My journey took me from Newtons laws of gravitation, to Einsteins theory of relativity, to Keplers work on planetary motion, with some great help from Stephen Hawking, in case you haven't read Stephen yet, he has a gift of explaining the complicated rather simply, for the older generations recommending his book 'A Brief History Of Time' may be an irritating cliche, but for those of you new to it, it's very good.

The Apollo 11 press kit released at the time from Nasa is also helpful, it contains exacting information about the whole moon landings topic - except it fails to brief you about the underpinning physics of how you get to the moon. After my research, my conclusion is yes, Nasa did go to the moon but let me explain how I got there...

So - how do you get to the moon and back in your Apollo spacecraft, well in order to navigate to the moon you need accurate data on planetary motion and orbits. We  know the moon is in orbit around the earth, and then we also know that the earth and moon are in another orbit around the sun. Incidentally, the sun is in orbit around the centre of the Milky Way galaxy we are in, the sun orbits the centre of the milky way because the gravitational pull is strongest there.

So when you calculate your navigation data to get to the moon and back you need to exactingly understand these orbits, otherwise you can get into the scary predicament whereby your Apollo spacecraft becomes a permanent satellite of the sun, not good. In order to navigate to the moon you need to work with celestial mechanics which is the study of how celestial objects ie planets and the sun move in motion with relation to their strongest influencing factor which is gravity. The primary determinate of celestial mechanics is Newtons laws of motion and gravity.  Johannes Kepler's three laws  help too by accurately describing the motion of the planets around the sun. Thanks to Kepler and Newton we do understand planetary motion and orbits and can navigate spacecraft extremly accurately in our solar system.

So you can navigate to the moon and back, but the next question is, how much energy do you need to get there? It sounds unbelievable doesn't it, that its possible to travel a quarter of a million miles each way, why doesn't this use up 10 000 rockets full of energy? The answer is a spacecraft requires much less energy for interplanetry travel and the explanation to this is provided by  Newtons laws of motion and gravity with a little help from Einsteins  theory of relativity.

Published in 1687, Sir Isaac Newton's 'Principia Mathmatica' explains in Newtons first law, the inertia of motion that if a body of matter (eg an Apollo spacecraft) is not exacted upon  by any force it will keep moving in a straight line at the same speed. Newtons first law also explains that the result of force exerted on a body is to change its speed rather than set it moving in the first place. Newtons second law of motion explains how the increase in speed of a body is relational to the amount of force deployed and the weight of the body. Newtons third law of motion says that for every action there is an equal and opposite reaction.

Newtons univeral law of gravitation which applies to objects everywhere universally ie on earth or in space says that any body attracts another body in exact proportion to the mass of each body, if the two bodies are the same weight, the attraction ratio is 1:1. The greater you move away from a body the lesser its gravitational force or more accurately the gravitational force between two bodys is inversely proportional to the square of the distance between the two objects. Newtons laws of motion and gravity make it possible to predict the planetary orbits, helped even further by Albert Einstein. Although almost perfect, Newtons law of gravity fails to factor in that space time bends when mass is exerted on it, Einstein in his theory of relativity showed how space time bends, a bit like putting a heavy bowling ball on a circus safety net, the circus net will sag and the sagging net illustrates how space time bends or sags under weight of mass. The bowling ball is your body of mass ie the sun and the circus safety net is space time. So now mathmeticians were able to calculate truly exact trajectories to other planets in our solar system, with thanks to Newton and Einstein and Kepler.

So the point of drilling down a little into gravity and motion is a bit of understanding of these naturally occuring forces explains why its possible to get to the moon with relatively little fuel. So as earth is a large body of gravity, the Apollo spacecraft used the largest amount of fuel to accerelate sufficiently to break the strong gravity of earth, burning all the fuel in two large Saturn rocket stages and releasing these two stages in to the Ocean.

Then, the Apollo 11 spacecraft is in orbit on earth, travelling at about 17.5 thousand miles per hour. Now we must refer back to Newtons first law of motion, once a body is travelling at a certain rate, its natural state is to keep travelling at that speed in a straight line unless any force of gravity or energy changes its speed. Another good way of thinking about this is the natural state of a body is not to be at rest. The Nasa spacecraft used a much smaller fuel burn from the stage three of the Saturn rocket to change the trajectory of Apollo 11 from an earth orbit, into a lunar course, this is called a slingshot technique, as you 'cash in' on your speed that you already have gained from accelerating to break earths gravity. Then during your orbit around the earth you slingshot into a lunar destination course.  So now your Apollo spacecraft is hurtling towards the moon at about 24 000 miles per hour, as there is some but very little gravity once you are out of earths immediate viscinity, its possible to accelerate a lot with little energy expended. According to Newtons laws, you just keep going at 24 000 mph towards the moon with almost no energy being used.
                                                                                 

(On the left you can see a NASA photo of the luna module section of the Apollo spacecraft descending towards the moon.)

The moon has 1/6 of the gravity of Earth. As Apollo 11 approached the moon it needed to burn some fuel to slow the spacecraft down, and of course after your moon escapades you need some fuel to get back up with your lunar module and rejoin the command and service module sections of Apollo 11 which were awaiting the lunar modules return in a lunar orbit piloted by Michael Collins. Once the lunar module had rejoined Armstrong and Aldrin with the Command module in lunar orbit, Apollo 11 ejected the lunar module  and burnt  some more fuel  to launch itself on a path back to earth, it requires  much less fuel leaving the moon to build up to speed as less energy or escape velocity is required to break away from the moons smaller gravity. As Apollo 11 travelled back to earth again at many thousands of miles per hour the Astronauts can make minor course corrections by doing a very small fuel 'burn' to ensure they are at exactly the right angle to safely re enter the earths atmosphere and splash down in the sea, in the command module. The exact figures you need of how much fuel burnt and at what stages, are in the 1969 Nasa Apollo 11 press release here should you want to read more.

A chief objection cited by moon landing conspicary theorists is that the Van Allen radiation belts would have fried the Apollo astronauts to death. I have researched this and there are 3 radiation belts surrounding earth that capture harmful radiation from the sun and protect us on earth. However if you pass through the Van Allen belts at speed, in a insulated spacecraft the dosage of radiation the Astronauts receieved would have been similair to that of going for an X ray. So yes, the Van Allen radiation belts are potentially deadly and dangerous but the Apollo astronauts exposure to them was extremely small indeed. Also even Mr Van Allen himself refutes the idea that the belts would have killed the astronauts along with many reliable science sources.

As for evidence to support the Apollo moon landings? Well there are some photos of the Apollo moon landing sites that a Nasa space probe  has taken more recently, these photos aren't bad and appear to corroborate the moon landings but the photos are inconclusive as they are not clear. Second there is strong third party evidence to agree that retroflectors are left on the moon. These retroflectors are reflectors that you can bounce a signal off from earth to the moon and back and the data back from the relectors indicate that a retroreflector is there at that point on the moon and not just moon terrain. There are also many examples of moon rocks bought back from the moon, geologists agree these moon rocks are not of this world.

Some of the objections that moon landing conspicary theorists throw up like the flag waving or discrepencies in foot prints feel somewhat specious and I don't feel they dignify a response personally. However people do justifiably question the computer that navigated Apollo to the moon. This computer was very small in processing power, 0.043 mhz of processing power with 64kb of memory. This MIT built Apollo 11 computer was no more powerful than a pocket calculator of todays standards. You had to type in basic nouns and verbs to program the Apollo guidance computer to navigate the spacecraft and this was all backed up by much bigger computers navigating back at mission control in houston. The Apollo guidance computer was basic but did useful work. Neil Armstrong famously over ruled the computer on his descent down to the moon and landed the Lunar Module by manual flying as the Apollo Guidance Computer was taking them down into a large crater. Neil kept his cool and landed successfully with 30 seconds of fuel left.

The strongest evidence to support the moon landings is that, at the time in 1969, independant from Nasa  telescope and radar observatories watched the signal from the Apollo 11 spacecraft go to the moon and back, on exactly the trajectory and times Nasa Published. The Soviet Union tracked Apollo 11 all the way to the moon and back at their  Space Transmissions Corps, which was fully equipped with the latest intelligence-gathering and surveillance equipment. Other independent radar in various locations around earth watched Apollo go to the moon and back also.

It looks very likely that the Americans did go to the moon, Nasa were operating at the absolute cutting of edge of science and technology to do it, really pushing it and it was clearly politically risky for the USA government. However the USA threw a ton of talent and money at the the moon landings and seem to have delivered.



The Americans are planning to return to the moon by 2020 and are planning to employ similair technology and science to the Apollo missions. The Americans plan to leave a moon base up there made up from several moon trips worth of discarded lunar modules.


So, the last question is, did Neil Armstrong prescript the lines  'One small step for man, One giant leap for mankind' or make them up on the spot as he claimed with a cheeky smile in interviews. Perhaps this is the only real moon landing conspiracy we may never know the answer too...





© Copyright James Bickle 2013.

 Bibliography

1) http://www.computerweekly.com/feature/Apollo-11-The-computers-that-put-man-on-the-moon
2) http://history.nasa.gov/alsj/a11/A11_PressKit.pdf
3) A Brief History Of Time, Stephen Hawking.
4) http://www.scientificamerican.com/article.cfm?id=third-van-allen-radiation-belt-makes-appearance-around-earth
5) http://www.independent.co.uk/news/science/the-apollo-hoax-theories-1730408.html?action=gallery&ino=3
6) Scott, David; Leonov, Alexei (2004). Two Sides of the Moon. St. Martin's Press. pp. 247. ISBN 0-312-30865-5.
7) Hansen, James R. (2005). First Man: The Life of Neil A. Armstrong. Simon & Schuster. p. 636.
8) http://www.space.com/17411-apollo-11-moon-landing-explained-infographic.html
9) http://www.youtube.com/watch?v=keoF8YmTjWg
10) http://www.space.com/15099-apollo-moon-rocket-engine-recovery-infographic.html
11) http://www.newscientist.com/article/dn10520-space-elevators-first-floor-deadly-radiation.html
12) http://www.encyclopedia.com/topic/celestial_mechanics.aspx#2
13) http://www.encyclopedia.com/topic/celestial_mechanics.aspx#1
14) http://www.popularmechanics.com/science/space/moon-mars/4317016



2 comments:

  1. I really hope it isn't just a conspiracy! Talk about ruining my childhood...

    ReplyDelete