Why Rocketry doesn't work in vaccum
My suspicion is that all rockets are ballistic, that is they go up and down based on Newtonian mechanics and that the idea that they can produce force outside of the atmosphere is a fantasy/dream.
A big problem with rockets in space continues to be
how does the gas expelled through the nozzle contribute any force to the system?
when:
1. Free Expansion says gas does no work entering the vacuum
2. The Laws of Gasses say gas can't exist in the vacuum
3. The Laws of Gasses say gas can't do any work in the vacuum
(note that 1., 2. and 3. above all agree with and support each other)
If the gas expelled from the ship in space produces no force how does the ship move?
1. In order for a rocket in space to move it must do work.
2. While a liquid fuel space rocket can generate energy there is no way for that energy to do work.
There are 4 major ideas on presented on the Internet, including NASA web sites, as to how rockets generate thrust in space
1. Newton’s 3rd Law : for every force there is an equal and opposite
2. Newtons’s 2nd Law : Force = Mass x Acceleration
3. Conservation of Momentum
4. The use of a specialized nozzle to accelerate the gas inside the ship, concentrate and aim the gas jet
1. Newton’s 3rd Law : for every force there is an equal and opposite
The problem with applying Newton’s 3rd is that the rocket’s propellant does not generate force in a vacuum according to the laws of physics and chemistry. If the force of the propellant is 0 then Newton’s 3rd states that
Force on Rocket=-Force of Gas.
If Force of Gas = 0 the rocket does not move.
Why doesn’t the propellant generate any force, it's expanding, right?
There is something known as “
Free Expansion” or the “
Joule-Thomson” effect, named after James Prescott Joule and J.J. Thompson two of the founders of the field of Physical Chemistry.
http://www.etomica.org/app/modules/site ... ound2.html
Free Expansion states that when a pressurized gas is exposed to a vacuum the gas expanding into the vacuum without any work being done. The gas is not “pulled” or “sucked” into the vacuum nor is it “pushed” out of the high-pressure container. In other words no work is done, no heat or energy is lost.
This result has been experimentally verified numerous times since its discovery in the 1850’s.
[for example a paper in the Journal of Physical Chemistry from 1902:
http://pubs.acs.org/doi/pdf/10.1021/j150043a002
As if Free Expansion wasn’t enough to invalidate the theory of rockets producing a force in a vacuum there is also a result from thermodynamics:
Work = Pressure x Change_in_Volume
that is easily found searching for “W=PV”
http://lsc.ucdavis.edu/~ahart/Alicia2B/Thermo.pdf
If the pressure of a system is 0 then the work done by the expanding gas into that system is 0. Gas expanding in a vacuum doing no work agrees with Free Expansion. This can also be understood as the gas meets no resistance as it exits into the vacuum and thus transfers neither heat nor energy to its surroundings. If the gas loses neither heat nor energy then it has done no work.
At this point we have a rocket with high-pressure gas generated from liquid fuel that can release the gas into a vacuum but has no way to produce a force while doing so. As soon as the nozzle is opened the gasses escape without doing any work.
Therefore the 3rd Law is rendered useless.
2. Newtons’s 2nd Law : Force = Mass x Acceleration
As it turns out NASA does not fall into the 3rd Law trap (nor does it go around correcting all the sites who do) instead claiming that thrust of a space rocket is generated using what I call The Wrong Formula, an egregious farce of Newton's 2nd law which I will address in a later next post.
NASA claims that by pressurizing gas and shooting really fast out of the back of a rocket they can create thrust in a vacuum.
Using only NASA web sites I can show that their equation for rocket thrust is bunkum.
First, the NASA rocket thrust equation (written in lay language)
Force = Mass x Velocity + (Pressure Difference between inside the rocket and the vacuum of space) x Nozzle Area
http://www.grc.nasa.gov/WWW/k-12/airplane/rockth.html
The first term says Force = Mass x Velocity whereas NASA web sites say that
Force = Mass x Acceleration (Newton’s 2nd law of motion)
NASA sites also say that Mass x Velocity = Momentum which is not a force. Momentum is potential energy. If you throw a rock it has momentum. If you throw it harder it has more momentum. No force is generated until the rock hits something. Gas shot out of the back of a rocket very fast does not create a force until it interacts with something, which it never does in the vacuum of space. It remains high momentum gas streaking endlessly through space looking to do work but never getting the chance.
The second term (Pressure Difference between inside the rocket and the vacuum of space) x Nozzle Area
violates the “free expansion” effect, part of the first law of thermodynamics by which pressurized gas moves into a vacuum without any work being done. It does not matter how highly pressured the gas is inside the rocket nor how fast it comes out. Because it is going into a vacuum the gas makes the trip “for free” and does not do any work, does not expend any energy and does not create any force or thrust.
The NASA space rocket equation has two terms the first of which is incorrect and so is the second. As Linus Pauling would say, “not even wrong”. How do rockets work in the vacuum space?
Free Expansion
http://er.jsc.nasa.gov/seh/f.html
Force = Mass x Acceleration
http://exploration.grc.nasa.gov/educati ... wtona2.htm
Momentum = Mass x Velocity
http://www.grc.nasa.gov/WWW/k-12/airplane/momntm.html
One of the unexpected things I found while doing research on space rockets was the effect called free expansion which states that a pressurized gas enters a vacuum without doing work. Rocket exhaust is pressurized gas therefore it does no work when it leaves the rocket.
That fact alone should be enough to stop people from considering liquid fuel space rockets.
Even if free expansion didn't exist, the exhausted gasses don't accelerate in the vacuum of space and if there is no acceleration there is no work. Force = Mass x Acceleration.
Moving gas into a vacuum, such as from inside a rocket in space to outside, is not a process that requires work. This is because free expansion allows enters a vacuum "for free", no work is needed or done. The gas does not push outward from inside the rocket and is not pulled in by the vacuum of space. Natures seeks to being the two sides, high pressure and zero pressure, into equilibrium and does so for "no charge". Although this is a well-known result in Physical Chemistry and Thermodynamics you almost never hear of it in the context of space rocketry because it wreaks havoc on the NASA-led theories of thrust.
The problems comes from NASA's equation for rocket thrust
http://www.grc.nasa.gov/WWW/k-12/airplane/rockth.html
Newton's 2nd Law states: Force = Mass x Acceleration
NASA's rocket formula states incorrectly that: Force = Mass x Velocity whereas in reality Momentum = Mass x Velocity
NASA cannot claim that momentum helps moves a rocket because momentum is not a force.
Momentum is a property, like mass.
Force is a push or a pull on an object.
They are different things.
While is seems like something moving very fast should push very hard it is only when the fast moving object meets another object that a force is generated (like a rock hitting a window generates force when the rock is slowed by the glass).
For those who say "the gas interacts with the ship, pushes on it", I say, no it does not via free expansion and in any case NASA does not even attempt to provide a term in their equation relating to the gas pushing against the ship.
Welcome to the world of scientific sleight of hand.
A ship that escapes into deep space, free of the earth's gravity, will not accelerate (change velocity) or change direction via rockets. Without a gravitational field accelerating the rocket its changing mass (due to lost fuel) will generate no force. Changing its mass would only change it's momentum.
3. Conservation of Momentum
Closed Systems
1. Even though the combustion chamber generates force there is no way for that force to be turned into useful work (e.g. moving the ship). This is because the ship is a closed system, like a battery or a thermos.
2. Every way we have of moving mass (objects) requires the object being moved to be connected to either gravity, an atmosphere or a solid at the initial point (when motion starts).
3. You can throw a ship into space, sure, but you can't change it's motion once it's up there using rockets because the ship isn't connected to anything and has no way to turn the force of combustion into motion.
2. Objects don't accelerate unless they exchange energy with some other object/field. There are no objects or fields in space (I regard them to be so small/weak as to be virtually non-existent)
[Space, for the purposes of this posting and all subsequent ones unless otherwise specified, is an environment without gravity or atmosphere. It is completely devoid of molecules or forces. Nothing acts on an object in space nor does any object act on space.]
If a space ship converts liquid fuel (potential energy) to accelerating gasses (kinetic energy) and then to a pressure imbalance against the combustion chamber (potential energy again) all it has done is moved energy around in a circle without doing any work.
In physics work is done only when energy leaves the boundary of a system. Since the rocket in this example has no place to deliver it's energy, (nothing borders the rocket: no atmosphere, no ground, no water, no gravitational field), then the energy stays within the rocker forever, doing no work and hence the rocket does not move.
So, looking at two models of rocket thrust
1. If we open the exhaust to let out gas free expansion takes over and no work is done. (NASA model)
2. If we create an imbalance inside the ship's combustion chamber we are in a closed system and no work is done.
Take a charged battery as an example. It is possible for the battery to exert a force without energy leaving the battery?
As per the equation Work = Force x Distance a battery does no work, generates no force until it's energy is passed to some object outside of the battery.
Perhaps it was unclear that I was referring to a closed system in my previous post. A closed system is one where no energy is exchanged with any object outside of itself. A ship in space represents a closed system as it does not interact with space and space does not interact with it nor does a ship in space interact with any field or force. If a ship cannot transfer energy to some object or entity outside of itself, how does it use its energy, potential or kinetic, to do work?
Here is what happens to a NASA style rocket powered by liquid propellant when it turns on it's engines in the vacuum of space:
1) The gasses inside the rocket do not to produce a force as they exit
In the vacuum of space the accelerated gasses inside the ship's nozzle are no longer pushed out of the ship. They enter the vacuum via the principle of free expansion (without performing work) and thus do work neither against the rocket itself nor the vacuum of space.
=>No work done by gasses inside of the ship
2) The gasses that leave the rocket do not produce a force once they have exited
In the vacuum of space the gasses that exit the rocket do not accelerate, they move at a constant velocity forever. If an object (including a molecule of gas) travels without accelerating it cannot produce a force. Hence the rocket produces no force.
=>No work done by gasses outside of the ship
I do not see where the force comes from that moves a NASA space rocket.
The issue is that the ship is a closed system much like a charged battery. There is nowhere for the energy to go, no way for it to do any work until it is connected to something external. The ship is perfectly insulated by space.
Yes, the ship can deform, bend, crinkle, etc... but this will not generate work. Much in the same way that while you cannot lift yourself off the floor by the scruff of your neck, because you and the floor are a closed system under influence of gravity and friction. Still, you can pull out your teeth, poke out your eyes, etc... (you can twist and deform your body but you cannot generate force enough to leave the floor).
Note that you can jump off the floor when you add potential energy by flexing your knees. This amounts to opening the system (interacting with gravity to create more force).
No amount of combustion or pressure inside the space ship can move the ship until that combustive force or pressure is exchanged with some object, entity, or field outside of the ship (a space ship is a closed system).
In every system that does work there is a transfer of energy from the object containing the engine/power to some other object/entity. In space there is no other object to receive the energy transfer energy. The vacuum of space neither receives nor delivers energy, it is an insulator.
Did you know that a thermos works because it contains a vacuum? The vacuum prevents heat transfer. It...insulates!
The only way heat can travel through a vacuum is via radiation. A vacuum is an insulator. Not a perfect insulator but, still an insulator, and one you use every day!
Does a NASA rocket produce/use radiation? Is a NASA rocket not insulated by space?
Free Expansion
1. is an effect that occurs when a high pressure gas enters a vacuum. It is not something to be concerned about inside a closed container like a combustion chamber.
2. operates at the nozzle and not in the combustion chamber. There has been confusion about where free expansion applies because some simplified models of a rocket engine have the combustion chamber venting directly into space whereas in reality the gas is released via a nozzle.
3. if it does not exist then the rocket exhaust will push against space. The high pressure gas, in this case, will do work against the vacuum when it exits the nozzle. This, in fact, is part of NASA's model. I disagree with the NASA model.
4. agrees with the equation for work done by a gas (Work = Pressure x Change_in_Volume). When pressure is 0 (space) gas does no work when it expands (enters the vacuum).
4. The use of a specialized nozzle to accelerate the gas inside the ship, concentrate and aim the gas jet
Also remember that the only work that can possibly be done on the ship is due to the expansion of the gasses as there is no gravity or other force available to accelerate it. If the gas in the ship is not allowed to do any work (prohibited by free expansion) the ship has no source of thrust.
From the experiments I have read about when gas exits via free expansion it does not generate heat, that is the gas molecules do not "fight to get out", they don't bump into each other or push each other out of the way. It is an orderly exit which makes sense if no work is done. Therefore the balloon should collapse without motion.
The gasses of a rocket are not propelled outwards into the vacuum of space. The enter space by means of free expansion, without doing any work without the application of any force. This is not some fantasy of mine. NASA admits free expansion exists although they keep it buried deep in the sand, as far away from their "rocket theory" as possible.
Solids do work in a vacuum, when they collide with other solids for example. Solids can have work done on them; you can throw a rock in space. Gas in a vacuum, on the other hand, seems to be incapable of either acting on an object or having an object act on it. For example, you can punch someone in a vacuum but can you "blow them over"?
"Nozzle Overexpansion & Underexpansion"
http://www.aerospaceweb.org/question/pr ... 0220.shtml
You may wish to read the above-linked article. Here's the basic problem illustrated by their 3-step diagram:
Now, wouldn't this be the logical progression of the above phenomena?
In other words, wouldn't the rocket plume eventually expand so much as to simply nebulize in all directions, thus ceasing to provide the necessary thrust/force to counter the pull of gravity? (This, of course, unless you believe that beyond a 'certain altitude', gravity ceases to be a force - and the spaceship gets 'flung' by its sheer momentum into 'free-fall' orbit...)
Lastly, you may ask, what type of rocket nozzle is used on modern spacecraft? Amazingly, it seems that the old De Laval design (1888 !) is still very much the (fixed)rocket nozzle widely used today... so much for technical innovation, NASA!
"Very nearly all modern rocket engines that employ hot gas combustion use de Laval nozzles."
http://en.wikipedia.org/wiki/De_Laval_nozzle
Links for reference:
"Rocket Nozzle Design: Optimizing Expansion for Maximum Thrust"
http://www.braeunig.us/space/sup1.htm
"ROCKET PROPULSION":
http://www.braeunig.us/space/propuls.htm
"Rocket engine nozzle"
http://en.wikipedia.org/wiki/Rocket_engine_nozzle
"Rocket engine"
http://en.wikipedia.org/wiki/Rocket_engine
When a rocket's combustion chamber is filled with accelerated gas opening the nozzle to expel the gasses into the vacuum of space does not generate a force against the ship. This is due to the principle of free expansion.
first of all it is my understanding that liquid can't exist inside a vacuum. Any liquid exposed to a vacuum is immediately converted to gas and any gas is immediately spread out into the void. So any combustion would have to take place in a sealed container and hence not in a vacuum in the strict sense.
Secondly, you mention the possibility of opening one side of a container, exposing it to the vacuum, while combusting gasses inside the container. In this case we have to consider that combustion can't occur anywhere near the opening because any liquids in that area are being instantly converted to gas by the vacuum and spread out into the void via free expansion. When combustion occurs at the far side of the container the force is going to push the remaining liquid out before it can be combusted. This seems like a terribly inefficient use of fuel as the combustion itself is forcing unspent fuel into space.
Another problem is that gas enters a vacuum at an average speed of about 2,000 meters a second. A 25 meter long Saturn 5 stage 2 fuel tank with over 1,000,000 liters of fuel would have it's contents drained in about 1/100 of a second if exposed to the vacuum of space.
The problem with a rocket engine is the interface between the accelerated gasses in the nozzle and the vacuum of space. From what I can tell, as soon as we open the nozzle to space even if for a a little while, to let out some accelerated gasses, those gasses are captured by the vacuum of space via free expansion and leave without doing work. Thus, we have burned fuel yet done no work. Eventually the ship runs out of fuel without ever moving under its own power.
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One issue is that there are no zero-gravity vacuums here on earth so it will be difficult to find an experiment that replicates the conditions in space. Also, you are not going to find scientists openly challenging NASA. Science, as you may have noticed, is a toe-the-line endeavor. Anyone who goes against accepted science is called a kook, denied funding and ostracized. The idea of a "maverick scientist challenging the status quo" is a fiction.
As such I have to build my case from scattered pieces of science and theory. This kind of investigation is always difficult for others to follow along.
I agree it's strange that they do these zero-gravity demos with water and other substances that you probably wouldn't want to expose to a billion dollars worth of equipment.
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Goddard's flawed test of the theory of rockets in a vacuum.
Physicist Robert Goddard (for whom the Goddard Space Center is named) was one of the first to claim that rockets would work in the vacuum of space.
The New York times mocked his ideas in a 1920 editorial.
http://en.wikisource.org/wiki/The_New_Y ... rt_Goddard
In response Goddard set up the following experiment to prove the NYT wrong:
Inside a vacuum tube he attached a .22 caliber revolver, loaded with a blank cartridge, to a rod that turns .
There is no film of the experiment but first hand reports claim that when he fired the gun it spun around four times. Thus Goddard declared his theory experimentally proven.
http://www.clarku.edu/research/archives/goddard/faq.cfm
I claim that his experiment was not a test of rocket thrust in a vacuum for the following reasons:
1. A
blank cartridge expels a plug of paper called a wad. The wad is expelled with enough force to kill a person. If a gun propels an object conservation of momentum applies and the gun will recoil. Rockets in space do not shoot bullets, wads or any such solids. They only expel gas.
http://en.wikipedia.org/wiki/Blank_%28cartridge%29
http://io9.com/5972313/why-a-gun-loaded ... l-kill-you
2.
The gun was attached to a rod which was attached to the top (or side) of the vacuum tube. This is not state of a rocket in space which is totally insulated from any other object. Because the gun is attached to a rod it is
not a closed system. The gun pushes against the rod (exchanges energy) when fired. In a proper setup the gun would be suspended in zero-gravity or some simulation thereof.
3. Even if he had arranged to fire a gun without expelling a wad, even if he had managed to simulate a gun in zero gravity and not used one attached to a rod, he still had the issue
that gas fired from the gun was interacting with the sides of his vacuum tube. If gas fired from the gun pressed against the sides it would create turbulence which means that the gasses leaving to gun barrel wouldn't have a chance to experience
free expansion. Space doesn't have "sides" that gas bounces off of. Every molecule goes flying off into the void without interacting with any other. Another way to think about this is that once the area in front of the gun muzzle is no longer a vacuum, free expansion stops.
(The loop at the bottom is so that it doesn't bounce off the bottom but what about preventing the gas from interacting with the sides?)
Goddard's experiment is critically flawed and cannot be used as evidence that a rocket will work in a vacuum yet it was used as the basis for continued funding, research and belief in space rockets.
Goddard's Vacuum Tube
(source
http://commons.wikimedia.org/wiki/File: ... 001338.jpg)
pushing apart the crimped metal is work (finally something we agree on). The work done to open the crimping is transferred to the gun, as energy. This work is then also transferred to the spindle and hence the gun revolves in Goddard's test.
Why does the gas do work in this case?
1. Because there is no vacuum inside of the ignited blank cartridge. The ignited blank cartridge is full of hot, expanding gasses. The vacuum is outside in the barrel of the gun and the chamber surrounding it. Therefore the gasses inside the cartridge can do work, such as blowing apart the crimped metal, without violating the principle of gas not doing work in a vacuum.
A rocket ship ignites fuel, filling a combustion chamber, and then releases that fuel into space. The combustion chamber does not explode while it is being filled. A blank cartridge is not a model of a rocket engine. Another failure on Goddard's part to simulate a space rocket in his laboratory.
I am 100% with you on your analysis of blank cartridges. I think Goddard's use of them was lazy and sloppy. Rather than design a system that isolated energies and forces he went with something cheap, fast and showy. The man had a PhD in physics and a gun on a spindle was the best he could do?
to clarify potential misunderstandings about my current beliefs:
1. when gas is contained it may do work. That includes in an atmosphere, like Earth, in a strong gravitational field, like the Sun, or in the combustion chamber of a space ship.
2. the movement of gas into a vacuum from a pressurized container does no work via the principle of free expansion. Being a principle, one must see whether it applies to a situation. I apply it to the rocket case because the pressurized gasses are first expanded in a combustion chamber and then released through a nozzle. This may not be the case for other examples we look at (such as the blank cartridge).
3. when gas is freely moving about the vacuum of space, outside of a container, atmosphere or gravitational field it does no work. This is important because when the gas leaves the nozzle of a rocket in the atmosphere it does work (the gas accelerates over a distance). In space this effect does not exist.
Solids are not subject to free expansion.
Free expansion only comes into play once you have gasses contained, under pressure, ready to be released. This condition is never satisfied by a blank cartridge and hence there is no free expansion.
he never measured the force generated nor compared it to the force of a gun under the same conditions in an atmosphere. Goddard was a sloppy scientist at best and a charlatan at worst.
Here's some more info on the pioneering experiments of the good Doctor Robert Goddard, one of the founders of rocketry:
March 16, 1926 Goddard conducts the first successful flight of a liquid fueled rocket. The only problem is that he didn't film it. Even though he brought along a film crew. The excuse is that they ran out of film before the rocket took off.
Goddard was head of the Clark University Physics Department, head of their Physics Laboratories and sponsored by the Smithsonian. And he didn't have enough film in the camera to film a 3 second flight? What were they there to film?
I went to youtube to see if I could find film of any of his flights and there is a 2 hour video of Goddard's greatest moments and as far as I can see in that incredibly boring 2+hour video that I haven't watched to the end none of his rockets ever flew.
No wonder he said rockets would work better in space. His rockets worked terribly on earth.
http://www.todayifoundout.com/index.php ... ed-rocket/
[youtube]Pq7WmrTbi-Q&feature=player_embedded[/youtube]
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And I've learned that if we actually want a decent sized vacuum chamber, the greatest two publicly known are both owned by NASA. And the largest is only a couple hundred feet on a side. The second largest is half the volume.
So while these might be large enough to test a small model rocket, if they are real, how is anyone going to have NASA cooperate with an experiment that might disprove their videos? Actually, someone we know with the ability to set up such an experiment through University or other government connections just figuring out a way to propose the experiment would be an interesting test of NASA's confidence in their vacuum-traversing rockets.
I guess a number of scheduling and paperwork 'mishaps' might occur before the experiment could go through, if the rocket wouldn't work in their vacuum.
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This is the absurd subversion of Newton's laws which NASA has sold to the public for decades:
"The rocket fuel (Force A) pushes against its own, vaporized self( Force B ). This force alone is what enables our rockets to attain the required 27.000km/h escape velocity which places them in orbit - and out of reach of Earth's gravity pull. Thereafter, no more fuel is needed and the rockets can be switched off - as the spacecraft is now safely free-falling, a bit like the moon orbiting our planet yet never falling down on us, you see?"
I'd say that burning that fuel will certainly expel it from its tank - but it wouldn't make any heavy rocket / spacecraft move upwards at any significant rate once the outside pressure reaches zero - or thereabouts.
THE MAGDEBURG HEMISPHERES experiment (1654)
Back in 1654, Otto Von Guericke, the inventor of the air pump (to simulate vacuum on Earth) performed a spectacular experiment. He had 16 horses trying to pull apart (in vain) two empty hemispheres held together only by the force of vacuum:
from a scientific CERN article:
"By this experiment he demonstrated that it is impossible to pull the two halves apart against the air pressure, even by using 2 X 8 horses (the counter-pressure by air in the interior of the sphere is missing). During this time, it became clear that we are living on the bottom of a huge ocean of air and that the mass of the atmosphere corresponds to a pressure of about 1kg per cm² or 10 tons on an area of 1m². The reason why we don’t feel anything of this tremendous pressure is simply that there is the same pressure inside our body."
http://www.cientificosaficionados.com/l ... 1-CERN.pdf
Indeed, folks: we are living on the bottom of a huge ocean of air - and that is something we all tend to forget. Imagine that: "10 tons on an area of 1m²". Pretty heavy stuff, huh?
fyi gas enters a vacuum at about 2,000 m/s (depends on the gas of course). So, as you point out, you're not going to get much thrust in space out of the 12 meter nozzle of an F1 engine in a Saturn 5 rocket. A molecule of gas that enters the nozzle is off into space in thousandths of a second.
http://adsabs.harvard.edu/full/1953ZA.....33..251K
I've been thinking about the pressure issue regarding space travel. As it turns out boats, planes and rockets (in the atmosphere), the 3 miracle machines of the modern age, all count on air pressure.
Metal boats float because of buoyancy, the pressure of the water below the hull is greater than the air pressure inside.
Planes fly because of lift, the pressure under the wing is greater than above.
All rockets equations have a thrust component which measures the pressure of the expelled gas.
Take away pressure (e.g. in the vacuum of space) and none of these three machines will work. Taking away pressure is like dividing by 0 in a math proof. Once you do it your answers are invalid even if you follow all the rules the rest of the way.
Rockets have to push against (or pull on) something. Just like everything else that moves.
A rocket pushing itself through the vacuum of space, totally isolated, touching nothing, being touched by nothing, is a fantasy born of hope and dreams, ignoring fundamental results in chemistry and physics.
Friction is the frenemy (friend + enemy). We need friction to start moving but then we want it to go away so we can keep moving. Space has no friction so we can't start moving in space (nor can we change direction, accelerate, etc...)
Well, with what I suppose would be somewhat basic physics, it would be possible to determine just how much air---intended to be blown into the vacuum---would be required to produce the distances and rates of travel proposed to us by NASA.
A chamber of gas relative to the size of say, Dublin, would fit the bill, no? On that note: bollocks.
Gas can't exist in a boundless, low-pressure, low-gravity vacuum like interstellar space. So it can't be used to move a rocket.
Gas only exists under pressure; in an atmosphere, in a container, in an extremely strong gravitational field, etc... Without pressure individual gas molecules fly away distancing themselves from each other at thousands of meters a second (depending on the specific heat) and no force is exerted in the process (no work done).
Using gas in space is like using ice cubes on the surface of the sun.
gas is only defined as existing within an area where it exerts pressure. Without pressure Boyle's law makes no sense: PV=k is an absurdity if pressure is 0. The Ideal gas law also makes no sense and so on. Gas not under pressure is like a solid without mass. It's nonsensical. You can't have one without the other.
There is no gas in outer space only scattered molecules without relation to one another. NASA and their aligned scientists group these molecules together as "gas" to make it seem like rocket gas can exist in the vacuum. Again, since these molecules do not exert any pressure they do not satisfy the condition of being a gas. But what does NASA care about science? They pick and choose the laws, theories and results to display to the public in order to make their picture of space travel seem plausible. It's starting to seem like there is barely any real science involved in space travel, the majority of the story being fantasy, imagination and trickery.
NB: Low gravity means that there is not much gravity, such as when you are far away from the nearest massive object. A vacuum is exactly what you think it is. Put those two together and you have the conditions of interstellar space through which a rocket must travel.
Space rockets are designed to work only in fantasies presented to us by production companies like NASA and Disney.
Science is against rockets working in space:
1. Gas can't push a rocket through space because:
i. Releasing gas into space does no work, creates no force.
ii. Gas ceases to exist once it enters the nozzle of a rocket in space and is exposed to the vacuum. Without pressure gas becomes only unrelated molecules swiftly dispersing into the void.
iii. A rocket can't push against something that doesn't exist nor can it use scattered, unrelated molecules as a propulsive force.
2. A rocket in space can only transfer energy from engine to hull and back again. No motion is generated. It is a giant battery connected to nothing.
3. Everything that moves must make an energy exchange with an object apart from itself (via a push or a pull). This is why a 90kg man can't pull himself off the floor and into the air but he can lift a 90kg weight off the same floor. A rocket cannot "push against itself" anymore than you can "lift yourself off the floor".
Rockets, like cars, boats and airplanes only function on the earth and in its atmosphere. Imaging them working anywhere else is science fiction.
As you well know, NASA's most extraordinary claim concerning propulsion physics is that their powerful rockets "do not push on air" when rising up to the skies. Air, they say, has absolutely nothing to do with propelling their spaceships - at all. We are told (again and again and ad nauseam) that it all has to do - exclusively - with Newton's laws, "for every action there is an equal and opposite reaction - so just get used to it, folks!" Now, a favorite NASA analogy is that of the RECOIL of a shotgun when firing a bullet. They'll say that the flame shot out from the rocket nozzle is just like a bullet exiting a shotgun, causing an equal and opposite recoil reaction and so pushing the rocket forwards. Therefore, NASA claims, rockets work fine both in the atmosphere and in a vacuum - since ALL OF their propulsive power comes from this equal action/reaction physics rule.
Well, as it turns out, this action/reaction isn't equal at all :
Misconceptions about recoil
Although energy must be conserved, this does not mean that the kinetic energy of the bullet must be equal to the recoil energy of the gun: in fact, it is many times greater. For example, a bullet fired from an M16 rifle has approximately 1763 Joules of kinetic energy as it leaves the muzzle, but the recoil energy of the gun is less than 7 Joules.
http://en.wikipedia.org/wiki/Recoil
The reason for the recoil's kinetic energy being
about 250 times weaker than the bullet's has to do with mass:
Physics of firearms - Kinetic Energy
However, the smaller mass of the bullet, compared to that of the gun-shooter system, allows significantly more kinetic energy to be imparted to the bullet than to the shooter. The ratio of the kinetic energies is the same as the ratio of the masses (and is independent of velocity). Since the mass of the bullet is much less than that of the shooter there is more kinetic energy transferred to the bullet than to the shooter.
http://en.wikipedia.org/wiki/Physics_of_firearms
[Physics buffs! Please go to the link and check out the relevant formulas and equations.]
So am I denying that rockets can fly? Not at all. Here's how I can see them working - in the atmosphere:
Simple, really: In order to vanquish force G - (Gravity and Drag) - the rocket causes an Action/Reaction (as of Newton's 3d law) between force A (rocket flame) and force R (the air/atmosphere). Force A will also add to the equation an extra recoil effect "r". The sum of R and "r" will provide (as of Newton's 2nd law)the needed acceleration to vanquish force G.
(Note that the kinetic energy of the recoil is but a marginal force here, given Mass M(rocket) and Mass m(rocket flame).
Now, here's what NASA claims:
To be sure, what NASA will tell you is that there simply is NO force "R"! "Air? Hohoho - no way, we need no air to push our rockets against! All we need is Newton's third law! Have you ever fired a gun in your life, sonny? Ever heard of recoil? "
In any case, here's the stuff they'll keep repeating - until your ears fall off:
"Goddard proved that a rocket will work in a vacuum, that it needs no air to push against"
"The truth is that the rocket does have something to push against: namely, its own fuel".
1. If the recoil of a gun absorbed as much energy as the bullet, it would be pretty lethal to fire a gun, and the bullet would lose the momentum required to fulfill its purpose.
2. The continuous stream of gas expelled through a rocket nozzle is not like a bullet fired from a gun. If it were, rockets would launch from the ground in awkward jerks, not smoothly, and would topple over in a matter of seconds. Imagine the destructive effect of a violent recoil on a 100-ton rocket standing upright on a launch pad! It would take more than one "wonderbolt" to keep the pieces together!
100,000 miles away from the earth the influence of it's gravity is .4% of what it is on the surface and that's not even halfway to the moon. Remember gravity is affected by the masses of the two objects involved. If one is tiny like a spaceship it's got to be close to the large object (e.g. planet) to feel a pull. Two really big objects can be farther apart and still pull on each other because of their combined masses are so great.
NASA is science education for a large segment of the population. Even though many people are aware of Newton and his laws they only know them in practice via NASA's explanations/demonstrations. They don't realize that Newton was working with solid bodies and not gasses. The folks working with gasses like Boyle and Joule are ignored by NASA because their results disagree with the official story.
Many people want to be a part of the exciting world of scientific discovery, the development of new technologies, the opening of new frontiers. The vast majority don't have the tools or the training to participate at a meaningful level so they just follow along looking at the pretty pictures, gasping at the bold exploits of space travelers and sitting at the feet of the wise scientists while pearls of wisdom drop from their lips.
See, NASA says that, in order to reach Earth Orbit their rockets need to accelerate to approx 8km/s. That's pretty damn fast, if you ask me - it's about 28.800km/h :
Rocketing into Orbit
"To reach Earth orbit, a rocket must accelerate to about 8 kilometers per second
—about 25 times faster than the cruising speed of a passenger jet."
http://howthingsfly.si.edu/propulsion/rocket-propulsion
I'm afraid I'll have to cite Newton's Third Law once again. Sorry, folks - I know... you've heard this one before!
"When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction to that of the first body."
Perhaps Newton's third law should have specified (and highlighted the importance of) the relative
masses of the two bodies involved. The bodies need to be of
equal mass in order for the "equal in magnitude" part of this law to be true. Or perhaps Newton DID specify that - but NASA has simply decided to ignore this crucial part and are happy to use the above, less-than-accurate phrase in the hope of getting away with their stratospheric lies. But let's get on.
Now, NASA denies that their rockets' propulsion has anything to do with any sort of interaction between their rockets' exhaust-thrust and air/atmosphere. Instead, they appeal to Newton's third law, saying that the exhausts of their rockets push on their own fuel/tank itself - and THAT is where and how the action/reaction occurs. They often compare this with the recoil of a bullet being fired by a shotgun. Of course, this is nonsense. A bullet has very little mass in comparison to a rifle and the man holding the rifle. For example, a bullet fired from an M16 rifle has approx
1763 Joules of kinetic energy as it leaves the muzzle, but the recoil energy exerted on the gun is less than
7 Joules. We may intuitively - and without resorting to complex equations - imagine that "recoil power" alone would not allow a given mass of rocket exhaust to lift a 100.000kg vessel from the ground - let alone propel it at supersonic speeds.
To attain the so-called escape velocity of 8km/s
with "recoil power" only, this is what NASA's rockets would have to do: they'd have to shoot out from behind their rockets, all at once (like a bullet from a gun) a mass equal to the mass of the vessel itself - at a velocity of 8km/s. This means that, if this were to be the case (that rockets move due to "recoil action/reaction")- more than half of any rocket's fuel mass would have to be ejected at that speed - as illustrated in this gif diagram:
Of course, this is not the case - and would be quite impossible to do. Yet, this is basically how NASA 'explains' how their spacecrafts are propelled through air and vacuum. Please note that I have respectfully observed Newton's Third Law in my above diagram. I think our poor friend Isaac is rolling and howling in his grave - seeing how NASA is abusing / distorting his laws in order to fool the world. Sadly, most people seem to keep buying into their shameless skullduggery.
Sometimes I look around the web to see how people are defusing the "do rockets really work in space?" question. It's generally pretty easy to debunk examples of how rockets work in space, that is after I filter out the ad hominem attacks.
Take this example from The Straight Dope
The Straight Dope wrote:Wearing ice skates on a slippery ice rink would be good, or maybe your office has a chair that rolls really well on a hard surface. Next, you'll need a medicine ball. You are the rocket and the medicine ball is your fuel. Toss the medicine ball. You'll notice that as you shove the medicine ball forwards, you yourself lurch backwards. Ta-da, the miracle of physics!
http://www.straightdope.com/columns/rea ... m-of-space
A test you can do at home to check their results:
Grab the medicine ball and jump into the air. Right when you hit the apex of your jump push the medicine ball away, just like you did when sitting on the chair. How far backwards do you lurch?
When you're sitting, it's the wheels, which do an excellent/efficient job of translating energy (from your push) into work, that cause you to roll across the floor. Rockets don't have wheels. Rockets don't roll across space.
If you jump into the air you lose this efficiency and basically you go nowhere. When you throw the ball you absorb most of the force inside your body and you just shake a little bit. So much for being able to say the magic word Newton and rockets suddenly work in space.
The Straight Dope example is debunked without even mentioning that gas (rocket exhaust) is not a solid (medicine ball).
below Lee De Forest interview. It is interesting to note that De Forest, inventor of the Audion (a vacuum tube that takes relatively weak electrical signals and amplifies them) was a space travel skeptic while, on the other hand, firmly believed that transoceanic television would be possible with "the skillful location of relay stations" and by taking advantage of the waves reflected by the ionosphere. In other words - without the need for launching costly telecommunication satellites into orbit...
http://news.google.com/newspapers?id=KX ... %2C6595098
(Perhaps unsurprisingly, for all his achievements and in spite of being considered in his time as "the father of radio and television", De Forest never rose to international fame and died relatively poor, with just $1,250 in his bank account. Here's just how important his vacuum tube invention was:
http://heinonline.org/HOL/LandingPage?c ... &id=&page=
Cold-Welding: a phenomenon relating to metals when they are in vacuum:
Vacuum Welds
Drawing Bead On Space Peril
Boston Globe (1960-1979) - Boston, Mass.
Author: DONALD WHITE
Date: Sep 12, 1965
Start Page: A_44
Pages: 1
Text Word Count: 264
One of the hazards of space travel is a phenomenon known as cold welding. The vacuum of space causes metal to stick together, a tendency that could be catastrophic in a space craft.
http://pqasb.pqarchiver.com/boston/acce ... atl=google
How do you lubricate anything supposed to work in the void, empty universe or on a moon?
2. Newton's 3rd Law only applies if an external force is present because
A system cannot "bootstrap" itself into motion with purely internal forces - to achieve a net force and an acceleration, it must interact with an object external to itself.
http://hyperphysics.phy-astr.gsu.edu/hbase/newt.html
A rocket in space is a single system without an external force.
A rocket in space cannot interact with the vacuum.
I say gas ceases to exist because just about every formula, property and function of gas requires you to know the pressure it is under. When that pressure is 0, all those laws, formulas and properties are invalid.
The mechanics of the process is that without pressure every molecule in the gas sprints off into infinity in it's own, unique direction without anything to stop it or slow it down. Gas molecules have a lot of energy, are always moving around, which is why gas expands, etc...
Shooting gas into the vacuum of space is like shooting ice cubes into the sun.
Newton's 3rd Law: action/reaction only works if you have two separate objects. More specifically these two objects have to be external to each other.
The reason you can't pull yourself off of the floor by your belt is that you are one object even though you are made of many parts: internal organs, muscles, arms, legs, clothes, etc...
You can pull a weight off the floor that weighs as much as you because it is external to you.
The combustion chamber of a rocket in space is internal to the ship. They are one object just like your arms are internal to your body and are one object when it comes to Newton's 3rd Law.
If you want to lift yourself by your arms you have to pull or push on something external to your body, like the floor or a rope, etc...
The rocket has to do the same thing if it wants to move. It has to push or to pull on something external to the ship. There is nothing in space to push against or to pull on.
You can exert as much energy as you want trying to lift yourself off the floor but if you don't connect to an external system you're not going to move. You may shake but you won't rise off the floor.
Same goes for a ship in space. You can combust all the gasses you want. If you don't generate an external force you're not going anywhere. People say "the ship is pressing on the gasses" but the gasses don't exist outside the ship. Gas doesn't exist in the vacuum. So the ship is left pressing against itself. A space ship is like a car with an engine but no wheels.
Every machine that moves is mechanical: relies on friction, pressure, exchanging energy with objects external to it. Everything except space rockets, that is. NASA might as well scrap rockets and go straight to saying we can teleport to the moon and other planets.
http://hyperphysics.phy-astr.gsu.edu/hbase/newt.html
As far as I can see nobody, not even NASA, has ever run a serious space rocket experiment. Where are the zero-gravity vacuum chambers big enough to fly rockets? There's a 17-mile long supercollider but the largest vacuum chamber is 120 feet.
Space science is like a cult run by ancient priests who speak to the Gods in private. We're not supposed to think for ourselves. We only wait until the NASA oracle tells us the great truths divulged only to them. This is not how science, nor modern, information-based, educated society is supposed to function. The goal of education is for us to learn how to figure things out for ourselves; to examine, to evaluate and to reason with the facts and data. What good is that training if, in the end, we can only shut up and believe what we are told with no proof, no solid theory behind it and no way to check the results or repeat their experiments ourselves?
Rocketry is not unique in this regard. Pretty much all the big results in science follow this pattern. Anyone who challenges the status quo is labeled an "idiot" or a "religious nut" which is ironic because science is behaving more and more like a religion based on faith and less and less of a method based on observation.
