Does Rocketry Work beyond Earth's atmosphere?

[simonshack]

My last post has disappeared. Does anyone know what might have happened, as I spent ages putting the diagrams together.

It was safely moved here, Sceppy - by Hoi. Please read his advice in his post below yours. Thanks - and sorry for the extra time / trouble this will cause you - but I agree with Hoi's move.

[Heiwa]

It is very simple! Rockets create thrust by expelling mass backwards in a high speed jet. Chemical rockets create thrust by reacting propellants within a combustion chamber into a very hot gas at high pressure, which is then expanded and accelerated by passage through a nozzle at the rear of the rocket. The amount of the resulting forward force, known as thrust, that is produced is the mass flow rate of the propellants multiplied by their exhaust velocity (relative to the rocket), as specified by Newton’s third law of motion. Thrust is therefore the equal and opposite reaction that accelerates (or decelerates) the rocket in vacuum.
One problem is, if you intend, e.g. round trips to the Moon as done by NASA 1969-1972, that you cannot carry the required amount of fuel (propellants) to fire the rocket engine. You get too heavy. Another problem is to direct the force correctly in 3-D space. If the force is applied in the wrong direction, you will go to hell.
Therefore all NASA Moon trips are fraud. It is not possible to go to the Moon. But the rocket works in vacuum.

[sceppy]

My last post has disappeared. Does anyone know what might have happened, as I spent ages putting the diagrams together.

It was safely moved here, Sceppy - by Hoi. Please read his advice in his post below yours. Thanks - and sorry for the extra time / trouble this will cause you - but I agree with Hoi's move.

Yes, I seen it. Cheers.
I'm fine with it all. I was just curious as to where it went to because I thought it may have been a glitch.
Advice heeded.

[simonshack]

Newton, you know!

I also like Newton, Heiwa. But NASA certainly do not like him, or else they would respect his good'ol laws of physics.


NASA and NEWTON

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.

[sceppy]

It is very simple! Rockets create thrust by expelling mass backwards in a high speed jet. Chemical rockets create thrust by reacting propellants within a combustion chamber into a very hot gas at high pressure, which is then expanded and accelerated by passage through a nozzle at the rear of the rocket. The amount of the resulting forward force, known as thrust, that is produced is the mass flow rate of the propellants multiplied by their exhaust velocity (relative to the rocket), as specified by Newton’s third law of motion. Thrust is therefore the equal and opposite reaction that accelerates (or decelerates) the rocket in vacuum.
One problem is, if you intend, e.g. round trips to the Moon as done by NASA 1969-1972, that you cannot carry the required amount of fuel (propellants) to fire the rocket engine. You get too heavy. Another problem is to direct the force correctly in 3-D space. If the force is applied in the wrong direction, you will go to hell.
Therefore all NASA Moon trips are fraud. It is not possible to go to the Moon. But the rocket works in vacuum.

A rockets hot gases, thrust into the dense atmosphere, makes the heat from them do an immediate about turn with the dense atmosphere under them, in hot pursuit as the hot gases slide up and down the entire rocket... all around it... which the dense atmosphere wants to equalize so it pushes the rocket up by friction.

It's like sitting in your bath tub with slippery hands and trying to grip the soap. Just think of the high pressure atmosphere as your hands and the hot low pressure atmosphere as the slippery wetness... and the soap as your rocket.

Now try and squeeze it. You can't squeeze it, because it keeps wanting to jump out of your hands. Well, imagine grabbing it with the other, and so on, one fist over the top, like one potato, two potato, three potato, four. That's how your burning fuel rocket works.

[Flabbergasted]

They often compare this with the recoil of a bullet being fired by a shotgun.

I think the conceptual difference between shotguns and rockets needs to be settled once and for all.

I am not the right person to do this, so I will limit my considerations to the following:

A: The recoil effect of a gun occurs because, for obvious reasons, the barrel is open to the outside at the time the gun powder is ignited. The recoil is simultaneous with the unobstructed forward motion of the bullet. If the cartridge were lodged in a closed chamber, the force of the explosion would be directed in many different directions, and would concentrate on the most fragile part of the structure. There would be a violent jolt, someone would lose an eye or a finger, but there would be no recoil as such.

B: As we have already seen, the combustion chamber of a rocket cannot be open to the outside, especially when "flying" in near-absolute vacuum since the fuel or gas would be lost in an infinitesimal fraction of a second. The gas resulting from the combustion is therefore not led into the environment through an unobstructed "barrel" but through a finely regulated nozzle/valve, in a perfectly continuous flow. In other words, if 100-ton rockets produce any recoil effect at all, it must be negligible.

[rusty]

I think we could put this discussion to rest once and for all if someone could conduct the following experiment:

Take a very small, pressurized bottle with a valve that can be triggered open automatically somehow. Lay it down on a skid or guide rail. Make sure the nozzle is unobstructed and far enough from any other object. Now open the valve and watch the bottle move along the rail until it comes to a halt. Try to put only as much pressure into the bottle that it is enough to move it. Now try this again in a near-vaccuum chamber. If Boethius is right, there should be a noticeable difference. If Heiwa is right, there should be no difference at all.

Anyone?

[sceppy]

I know I go on about atmospheric pressure but I feel the need to keep mentioning it as it honestly requires people to scrutinise it, to understand its important role in everything we do. From rockets to guns and so on.
The low pressure atmosphere versus high pressure is the key when we are talking about how rockets work, or even guns.

A gun barrel has close to 15 pounds per square inch of pressure inside it. Now when fired...the gun goes through 'two' recoils... but a person just feels one recoil due to the immense speed of the bullet.
The first recoil is obvious, which is the detonation of the bullet out of the shell casing and you get action and reaction of the ignited powder charge.
The second recoil happens, when the hot gases propel the bullet out of the end of the gun barrel. The bullet has expelled most of the 15 psi air inside of the barrel, so once it exits the barrel, the atmosphere immediately wants to equalise the pressure, so it forces its 15 pound psi pressure back inside, which produces the second and most telling recoil.

Now you would think that the pressure going back into the barrel...causing the recoil would make sense as to how the rocket works...but a rocket does not fire bullets.
A rocket BURNS its fuel. That's all it does.
It does not intermittently spit it out... creating a machine gun effect recoil...it simply burns under immense pressure.
Unlike a gun which creates a low pressure environment inside its barrel due to heat, which is immediately filled...a rocket creates 'continuous' heat...but under it...and heat does not like to be thrust downwards...it prefers up.

The thing is...the heat cannot go back up the rocket nozzle, because it's going back up against an even lower pressure, so it deflects around it and up the 'outside' of the rocket.
This is all happening in nano seconds or instantaneous.

Now, as the heat is going up the outer body of the rocket...it's cooling and compressing, due to the denser atmosphere attempting to equalise the pressure... and in doing so, it grips and pushes the rocket all the way up with a friction grip push.

I wish I could find a better way to explain it but I promise you, this is what happens.

[Flabbergasted]

I think we could put this discussion to rest once and for all if someone could conduct the following experiment:

Take a very small, pressurized bottle with a valve that can be triggered open automatically somehow. Lay it down on a skid or guide rail. Make sure the nozzle is unobstructed and far enough from any other object. Now open the valve and watch the bottle move along the rail until it comes to a halt. Try to put only as much pressure into the bottle that it is enough to move it. Now try this again in a near-vaccuum chamber. If Boethius is right, there should be a noticeable difference. If Heiwa is right, there should be no difference at all.

Anyone?

I don´t think it would make us much wiser.

- The air coming out of the bottle would interact with the wall of the vacuum chamber
- The vacuum would cease to be a vacuum
- The bottle would interact with the ground through the rail
- The vacuum chamber would not reproduce a space-like scenario of near-absolute weightlessness

[rusty]

- The air coming out of the bottle would interact with the wall of the vacuum chamber
- The vacuum would cease to be a vacuum
- The bottle would interact with the ground through the rail
- The vacuum chamber would not reproduce a space-like scenario of near-absolute weightlessness

All true, though weightlessness does not matter much here. But, if you keep the bottle very small relative to the size of the chamber, the interfering effects should be minor. I don't say the bottle won't move at all. Still the difference should be evident, if Boethius is correct. If Heiwa is correct, there should be almost no difference at all.

[Boethius]

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

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).

[Heiwa]

The Straight Dope example is debunked without even mentioning that gas (rocket exhaust) is not a solid (medicine ball).

It doesn't matter if a mass m is solid, fluid or a gas. As long as a force is applied on it - solid, fluid or gas - the mass will accelerate. Ever heard about a hurricane? It is force applied on air. Vacuum is evidently not solid, fluid or gas as it is empty nothing with no mass so I agree it is difficult to apply a force on vacuum. But vacuum is full of particles like photons, gravitons, etc, with no mass, so vacuum is actually full of things with no mass. Vacuum space is also full of planets, stars and other objects ... so it is not really empty. Some people suggest that vacuum space is also full of DARK ENERGY that cannot be seen ... and maybe it is the reason why rocketry actually works in the vacuum? What do you think? That Newton is wrong?

[Boethius]

The Straight Dope example is debunked without even mentioning that gas (rocket exhaust) is not a solid (medicine ball).

It doesn't matter if a mass m is solid, fluid or a gas.

It matters because gasses can't exist without being under pressure. Same goes for liquids. There is no gas floating around in outer space.

This is something the NASA apologists never talk about.

Newton, by the way, doesn't apply to imaginary objects such as gases in space.

The first step towards believing in space rockets is to ignore basic chemistry.

[Boethius]

Heiwa, I decided to address the remainder of the points made in your previous post.

Vacuum is evidently not solid, fluid or gas as it is empty nothing with no mass so I agree it is difficult to apply a force on vacuum.

Difficult? How would you propose one can apply force on a vacuum?

But vacuum is full of particles like photons, gravitons, etc, with no mass, so vacuum is actually full of things with no mass.

These massless particles exert no pressure and do not obey Newton's laws, or the Ideal Gas Law, etc.... So what do they have to do with rocket propulsion?

Vacuum space is also full of planets, stars and other objects ... so it is not really empty.

Space is defined as the area between these planets, stars and other objects. But I'm sure you already knew that. The universe is not empty but, space, by definition is. Wow. You sound more and more like a NASA shill every day.

Some people suggest that vacuum space is also full of DARK ENERGY that cannot be seen ... and maybe it is the reason why rocketry actually works in the vacuum?

I see. There is some imaginary, unseen force propelling rockets through space...but NASA is hiding it from us? Perhaps it's the same force that keeps Santa's reindeer aloft.

What do you think? That Newton is wrong?

No. I think that NASA shills and apologists use the word Newton as if it held some magic power such that once uttered all scientific analysis and logical reasoning must cease and whatever the speaker wants to be true is automatically so without further investigation. When all fails, the shills call on Newton the solid body physicist who never considered gasses or liquids.

[hoi.polloi]

Okay Boethius, I am going to make a slightly unorthodox request here and say, 'ease up' on our Heiwa.

I'm not saying you're wrong about Heiwa's argumentation style. But if you've caught this fellow on him trying to catch you on semantics, the argument is about words and not science, anymore. You have clearly made your point with aplomb. Let's not call Heiwa a shill because he may be mistaken about engineering principles and he's trying to point out where he thinks you might be disingenuous. As long as he sticks to Earth and ocean sciences, he has been quite a good asset to the forum.

Let's give this topic a rest for a while until new information comes to light. We all know the kinds of experiments we'd like to see to prove or disprove free expansion's limitations on rocketry. When that information arrives, let's unlock the topic and address it then. For now, we'll make the thread sticky so everyone can catch up on the debate.

At the very least, it is safe to say everyone seems to agree that NASA/ESA/JAXA/CNSA rocketry stories are fishy and likely totally bogus. Since this incredible information throws into doubt the entire imagery pool claimed to have been achieved from satellites, probes and rockets, the question of the exact quantities of weakness in an impotent technology is temporarily moot.