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Author Topic: thrust does not work in space  (Read 58262 times)

Offline Pmb

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Re: thrust does not work in space
« Reply #75 on: 17/09/2013 17:15:40 »
Quote from: dlorde
The experiment is demonstrated every time a rocket fires in space - which happens often. Satellites, probes, space labs - they all do it.
That’s enough to prove to anybody that this is in fact that case, except truthseeker67 since he doesn’t understand the concept in the first case.

If I haven't mentioned this before I’ll do so now; he just can’t grasp Newton's third law which states that wherever there is an action there is an equal and opposite reaction. See http://scienceworld.wolfram.com/physics/NewtonsThirdLaw.html

Note: There are exceptions to this law such as in electrodynamics, but not in this case.
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #76 on: 17/09/2013 18:12:16 »
Even if he did understand Newtonian physics, he still asserts that high orbits and free flight are the products of conspiracy and fakery, not real engineering achievements. He is clearly deluded. Any proper scientist knows that astronauts are borne aloft by noble thoughts and good fairies. I just wish he could convince my flight examiners, who always demand a very mundane demonstration of classical physics. 
 

Offline Pmb

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Re: thrust does not work in space
« Reply #77 on: 18/09/2013 02:02:11 »
Even if he did understand Newtonian physics, he still asserts that high orbits and free flight are the products of conspiracy and fakery, not real engineering achievements. He is clearly deluded. Any proper scientist knows that astronauts are borne aloft by noble thoughts and good fairies. I just wish he could convince my flight examiners, who always demand a very mundane demonstration of classical physics. 
Forgive me for not paying close attention (LOL!) but I haven't been following him in detail. Where did he make such claims?
 

lean bean

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Re: thrust does not work in space
« Reply #78 on: 20/09/2013 19:40:59 »
Forgive me for not paying close attention (LOL!) but I haven't been following him in detail. Where did he make such claims?
Stay awake boy 

Look have you ever asked yourself why all the satalites and space station included are all only in orbit, there is not one item of any sort further than orbit because they cant get there. they call something a space station but in fact it is not in true space it is still in the earths boundarys which we call orbit and guess what thrust works there and guess why?
My bold
 

Offline CliffordK

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Re: thrust does not work in space
« Reply #79 on: 21/09/2013 01:03:44 »
Look have you ever asked yourself why all the satalites and space station included are all only in orbit, there is not one item of any sort further than orbit because they cant get there. they call something a space station but in fact it is not in true space it is still in the earths boundarys which we call orbit and guess what thrust works there and guess why?
My bold
Not one item that isn't in orbit?

Voyager 1
Voyager 2
Pioneer 1
Pioneer 2

That adds up to at least 4.  And, I think there are a few more, not counting those probes that have been sent to other planets such as mars, either landing on the planet, getting destroyed in the atmosphere, or inserted into orbit around another planet. 

The International Space Station is in "orbit", rather than a non orbital trajectory because it was assembled in parts in space, and it is hard to get volunteers for Pluto flybys, especially when they turn the space heaters down to about 4K.
 

Offline dlorde

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Re: thrust does not work in space
« Reply #80 on: 21/09/2013 01:17:20 »
Not one item that isn't in orbit?

Voyager 1
Voyager 2
Pioneer 1
Pioneer 2

That adds up to at least 4.  And, I think there are a few more, not counting those probes that have been sent to other planets such as mars, either landing on the planet, getting destroyed in the atmosphere, or inserted into orbit around another planet. 
I did put up a link to a nice poster of missions earlier.
 

Offline Supercryptid

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Re: thrust does not work in space
« Reply #81 on: 21/09/2013 02:23:47 »
Look have you ever asked yourself why all the satalites and space station included are all only in orbit, there is not one item of any sort further than orbit because they cant get there. they call something a space station but in fact it is not in true space it is still in the earths boundarys which we call orbit and guess what thrust works there and guess why?
My bold
Not one item that isn't in orbit?

Voyager 1
Voyager 2
Pioneer 1
Pioneer 2

That adds up to at least 4.  And, I think there are a few more, not counting those probes that have been sent to other planets such as mars, either landing on the planet, getting destroyed in the atmosphere, or inserted into orbit around another planet. 

The International Space Station is in "orbit", rather than a non orbital trajectory because it was assembled in parts in space, and it is hard to get volunteers for Pluto flybys, especially when they turn the space heaters down to about 4K.

He thinks that the Moon landings are a hoax and that NASA can't be trusted. He probably thinks that each and every one of those missions are faked and that there is a world-wide conspiracy in place to keep anyone from learning that.
 

lean bean

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Re: thrust does not work in space
« Reply #82 on: 21/09/2013 16:33:27 »
Can anyone find anything about the natural jets on comets affecting the comet in some way?
 I understand there must be some sort of cavern in which the contents quickly become gaseous in a confined space, resulting in pressure on all surfaces within the cavern, until one part 'gives'.
I could only find this...
Quote
Dr A'Hearn mentioned that if the comet "spins up" (i.e the jets increase the rotation rate), there is a possbility of it fragmenting (like C/2007 Q3). Will ground based scopes or the spacecraft continue to track 103P and for how long to see if this increase in spin rate occurs?
From NASA http://www.nasa.gov/connect/chat/hartley_chat.html

« Last Edit: 21/09/2013 16:43:19 by lean bean »
 

truthseeker67

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Re: thrust does not work in space
« Reply #83 on: 23/09/2013 11:09:25 »
There is also a philosophical reason why NASA space rocketry is impossible: gas, via rocket engine exhaust or otherwise, has no effect, does no work, in a vacuum and cannot be used to move objects through space.

In 1852 scientist James Prescott Joule, for whom the unit of energy Joule is named, discovered that gas does no work in a vacuum http://www.etomica.org/app/modules/site ... ound2.html

If gas has an effect on objects in a vacuum I would expect to find an example in nature. All forces that man has access to exist in nature (including fission, fusion, chemical reactions, steam, etc...). We do not create forces we only discover them. In ancient times people thought a comet's tail was a gas jet pushing it along. Today I cannot find an example of an object moving through space via gas/jet propulsion although streams of gas and particles shooting into space exist. Saturn's moon Enceladus, for example, shoots a jet of water ice 500 KM into space. The diameter of the moon itself is only 500 KM. Does this jet have any effect? No. The jet as tall as the moon is wide goes harmlessly off into space. http://en.wikipedia.org/wiki/Enceladus_%28moon%29
 

Offline dlorde

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Re: thrust does not work in space
« Reply #84 on: 23/09/2013 12:26:20 »
There is also a philosophical reason why NASA space rocketry is impossible: gas, via rocket engine exhaust or otherwise, has no effect, does no work, in a vacuum and cannot be used to move objects through space.
That's not a philosophical reason. It's an explicitly physical reason - and, of course, it's nonsense. Posting broken links won't make it less so.
« Last Edit: 23/09/2013 12:27:51 by dlorde »
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #85 on: 23/09/2013 15:27:22 »
Quote
In 1852 scientist James Prescott Joule, for whom the unit of energy Joule is named, discovered that gas does no work in a vacuum

But a rocket in a vacuum is not a vaccum. The gas does work on the rocket, which is why it moves. Exactly as Newton stated, and as everyone who has ever designed, used or seen a rocket or jet engine, fired a gun, or even farted on an ice rink,  knows perfectly well.

Philosophy? Get a life.   
« Last Edit: 23/09/2013 15:28:58 by alancalverd »
 

lean bean

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Re: thrust does not work in space
« Reply #86 on: 23/09/2013 20:42:08 »
Today I cannot find an example of an object moving through space via gas/jet propulsion  although streams of gas and particles shooting into space exist. Saturn's moon Enceladus, for example, shoots a jet of water ice 500 KM into space.

The jets on Enceladus were discovered by the interplanetary spaceprobe Cassini. How did Cassini get to Saturn and its moon Enceladus, if thrust doesn't work in space?

Quote
The plumes of water vapour were discovered by Cassini in 2005 and seemed to be related to the tiger stripes, but their precise source was unknown until now.
From http://www.newscientist.com/article/dn12770-source-of-saturn-moons-mysterious-jets-pinpointed.html
« Last Edit: 23/09/2013 21:00:59 by lean bean »
 

Offline dlorde

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Re: thrust does not work in space
« Reply #87 on: 23/09/2013 21:53:49 »
The jets on Enceladus were discovered by the interplanetary spaceprobe Cassini. How did Cassini get to Saturn and its moon Enceladus, if thrust doesn't work in space?
Ah, hoist by his own petard, methinks! :)
 

truthseeker67

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Re: thrust does not work in space
« Reply #88 on: 23/09/2013 22:14:44 »
Gas does no work in a vacuum. It is only a passive participant and not an active force in space. We cannot use it as the basis for space travel. Bottling up gas and shooting it out of a tiny nozzle won't change its basic physical properties inside a vacuum, won't suddenly invalidate the laws of thermodynamics.

The theory of space travel based on gas jets and/or liquid propellants is a science fiction from the 1800's (Jules Verne et. al.) similar to the philosopher's stone and other magical, mystical pursuits we now look down upon. There is also the matter of the faked/fraudulent results of rocket pioneers such as Goddard which I will get to later.

If you ask why this is hoax is still going on it is because science has become a religion and NASA it's church. Specifically space travel is one of the Holiest of Holies. Try debunking a religion/cult and see how far you get. Once someone has been indoctrinated, invested themselves in its beliefs, it is nearly impossible for them to divest. For years I believed that space travel was the pinnacle of man's achievement. Now I have to wonder if any rocket has ever been past as far as we can throw it up from the ground.
« Last Edit: 23/09/2013 22:28:53 by truthseeker67 »
 

Offline dlorde

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Re: thrust does not work in space
« Reply #89 on: 23/09/2013 22:36:41 »
... Once someone has been indoctrinated, invested themselves in its beliefs, it is nearly impossible for them to divest.
You've certainly convinced me of that !

I blame Newton, with his stupid 3rd Law.

But what about the jets from Enceladus discovered by Cassini? How did Cassini get there to discover them?
« Last Edit: 23/09/2013 22:41:45 by dlorde »
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #90 on: 23/09/2013 23:01:24 »
Gas does no work in a vacuum.

There's little point in carrying on this discussion if you don't read the replies.  See #85 above.
 

Offline Supercryptid

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Re: thrust does not work in space
« Reply #91 on: 24/09/2013 04:07:09 »
I still want to see him directly address the cube argument that lean bean posted earlier. I find it kind of funny how he just brushed it off by saying "I can see what you mean with the cube" and leaving it at that. What? Can't find a good way to argue against it?
 

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Re: thrust does not work in space
« Reply #92 on: 24/09/2013 04:13:16 »
Look have you ever asked yourself why all the satalites and space station included are all only in orbit, there is not one item of any sort further than orbit because they cant get there. they call something a space station but in fact it is not in true space it is still in the earths boundarys which we call orbit and guess what thrust works there and guess why?
My bold
Good Lord! The man doesn't even know what it means to be in space or in orbit
 

Offline Pmb

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Re: thrust does not work in space
« Reply #93 on: 24/09/2013 04:14:28 »
Look have you ever asked yourself why all the satalites and space station included are all only in orbit, there is not one item of any sort further than orbit because they cant get there. they call something a space station but in fact it is not in true space it is still in the earths boundarys which we call orbit and guess what thrust works there and guess why?
My bold
Not one item that isn't in orbit?

Voyager 1
Voyager 2
Pioneer 1
Pioneer 2

That adds up to at least 4.  And, I think there are a few more, not counting those probes that have been sent to other planets such as mars, either landing on the planet, getting destroyed in the atmosphere, or inserted into orbit around another planet. 

The International Space Station is in "orbit", rather than a non orbital trajectory because it was assembled in parts in space, and it is hard to get volunteers for Pluto flybys, especially when they turn the space heaters down to about 4K.

Don't forget the many many satellites which are in geosyncrhonous orbit around the earth
 

Offline Pmb

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Re: thrust does not work in space
« Reply #94 on: 24/09/2013 04:16:14 »
There is also a philosophical reason ...
You've lost all credibility now that you've demonstrated a complete lack of understanding of nearly all areas of physics. You have nothing to share that I want to know and I'm certain everyone else feels the same way.
 

Offline bizerl

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Re: thrust does not work in space
« Reply #95 on: 24/09/2013 05:21:36 »
Gas does no work in a vacuum. It is only a passive participant and not an active force in space. We cannot use it as the basis for space travel. Bottling up gas and shooting it out of a tiny nozzle won't change its basic physical properties inside a vacuum, won't suddenly invalidate the laws of thermodynamics.

The theory of space travel based on gas jets and/or liquid propellants is a science fiction from the 1800's (Jules Verne et. al.) similar to the philosopher's stone and other magical, mystical pursuits we now look down upon. There is also the matter of the faked/fraudulent results of rocket pioneers such as Goddard which I will get to later.

If you ask why this is hoax is still going on it is because science has become a religion and NASA it's church. Specifically space travel is one of the Holiest of Holies. Try debunking a religion/cult and see how far you get. Once someone has been indoctrinated, invested themselves in its beliefs, it is nearly impossible for them to divest. For years I believed that space travel was the pinnacle of man's achievement. Now I have to wonder if any rocket has ever been past as far as we can throw it up from the ground.

I realise I'm trying to enlighten a dead horse here but surely the gas itself is of little importance in the thrust of a spaceship. It is the explosion inside the ship (and therefore not even in a vacuum if it matters - which it doesn't) which drives the gas out through the jet on one side of the ship, but doesn't drive the gas out of any other wall in the engine and therefore the ship has no choice but to move in the direction that the gas is not leaking out of. This was the beautiful cube example from earlier.

You can't see that you've indoctrinated yourself to believe this fallacy about thrust in space blindly, without analysing the evidence around you and providing alternate theorys to explain the observations.
 

Offline Pmb

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Re: thrust does not work in space
« Reply #96 on: 24/09/2013 07:32:29 »
Quote from: bizerl
You can't see that you've indoctrinated yourself to believe this fallacy about thrust in space blindly, without analysing the evidence around you and providing alternate theorys to explain the observations.
We've all accepted that as a given at this point.
 

Offline CitronBleu

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Re: thrust does not work in space
« Reply #97 on: 24/06/2014 13:59:36 »
Hello TNS forum members,

I am interested in the problematic posed by this thread and wish to continue the discussion.

... it's down to words not just pictures. :)

Indeed, dear Beany.

Imagine a hollow cube in interstellar space, at the centre of this cube there is an explosion. Each inner wall of the cube will receive an equal pressure (push) from the expanding gasses of that explosion, and so the cube does not move in any direction.

Take away one wall of that cube, and repeat the central explosion.

Again, the gaseous particles hit all walls with equal pressure except the missing wall. The pressure on the wall opposite that missing wall is not countered, and so the cube moves in the direction opposite to the missing wall.
Thrust in interstellar space.

Beany,

You assume time and space have no affect on the pressure produced against the wall opposite the missing wall by the explosion.

EDIT for clarity and grammar
« Last Edit: 24/06/2014 14:13:38 by CitronBleu »
 

Offline PmbPhy

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Re: thrust does not work in space
« Reply #98 on: 24/06/2014 17:27:13 »
Quote from: CitronBleu
You assume time and space have no affect on the pressure produced against the wall opposite the missing wall by the explosion.
That's more than a mere assumption; it's an empirical fact and conforms to the laws of physics. Beany is describing the implications of Newton’s third law – where there is an action there is always an equal and opposite reaction. See
http://scienceworld.wolfram.com/physics/NewtonsThirdLaw.html

The box in Beany’ s example is a simplified form of a combustion chamber. Here’s an even simpler example; if you through a ball against a wall the ball will bounce off the wall. That happens because the ball exerts a force on the wall. In response to the force exerted on the ball by the wall, according to Newton’s third law, the ball exerts an equal and opposite force on the wall. That’s one of the most well accepted facts in all of physics. This has been a well-established empirical fact for well over 300 years now. A great deal of what happens in nature is based on this fact.

The topic of this thread is how thrust affects a rocket. The opening post was off off about all of this. We (or at least I) corrected him. It should have been obvious to him that if he were right then all the rockets we've used to explore space would never have worked. The space shuttle wouldn’t have been able to do all the things that we know that it did, we'd never have been able to send probes to Mars and most of the other planets in the solar system and we’d never have a Global Positioning System (GPS) that many people use nowadays. Very simply put, thrust works be bouncing material off of a one of the rear combustion chambers wall. This exerts a force on that wall which is then transmitted by the structure of the rocket to the rest of the rocket. Nasa has a web page online on this subject at
http://exploration.grc.nasa.gov/education/rocket/rktth1.html



Then we were insulted for our efforts with the claim that all cranks use, i.e. that we're all brain washed and can't think for ourselves, which is utter nonsense. Part of a physicists training is lab work where we experimentally explore what we learn in class. So we aren’t merely told these things but are expected to observe them in the laboratory for ourselves. The person who created this thread based all of his claims with the assumption that is all based on the following assertion
Quote
thrust equals = weight in order to have weight we need gravity….thrust=0 because without gravity there is no weight behind the thrust to cause a reaction so no movement would take place.
which is quite wrong for the reason stated above. I have to say that it’s quite irritating when people with essentially zero formal training in physics comes here to claim that all the physicists in the world during the last 300+ years are all wrong and only he is right. That’s arrogance taken to the extreme.

Here’s how he argued it
Quote
look when water comes out of a hosepipe with high pressure it is simply chucking out
weight, and thrust is weight why do you think rocket engines are said to create pounds of thrust,
This statement proves that he doesn’t know what he’s talking about. Recall that NASA used rocket sleds to train astronauts. The sled had a rocket engine on it and when ignited the rocket engine exerted a force on the sled accelerating it down the track. The only weight operating here is the force exerted by gravity in the vertical direction. But the force on the rocket sled exerted a force in the horizontal direction which means according to him it wouldn’t work. Also he thinks that the term pounds of thrust refers to weight which is quite false and actually a quite ignorant assumption. In the context in which he used it the term pound refers to a unit of force. See http://en.wikipedia.org/wiki/Weight and scroll down to where it says Pound and other non-SI units
Quote
In United States customary units, the pound can be either a unit of force or a unit of mass
We would have explained this to him but he didn’t come here to learn. He came here to spread his “theory” which we explained to him was wrong and why it was wrong. He wasn’t receptive to learning though.
 

Offline CitronBleu

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Re: thrust does not work in space
« Reply #99 on: 25/06/2014 05:23:43 »
Quote from: CitronBleu
You assume time and space have no affect on the pressure produced against the wall opposite the missing wall by the explosion.
That's more than a mere assumption; it's an empirical fact and conforms to the laws of physics. Beany is describing the implications of Newton’s third law – where there is an action there is always an equal and opposite reaction.

Hi PmbPhy,

To what empirical fact are you referring ? To what laws of physics does this fact conform ? My assumption, shared by others, is that man has never achieved flight beyond a hypothetical 80-120 Km altitude.

This empirical fact must have been discovered early in the years which led to the formulation and then to the development of the space conquest narrative (Which I will call SCN for short.).

Quote
The box in Beany’ s example is a simplified form of a combustion chamber. Here’s an even simpler example; if you through a ball against a wall the ball will bounce off the wall. That happens because the ball exerts a force on the wall. In response to the force exerted on the ball by the wall, according to Newton’s third law, the ball exerts an equal and opposite force on the wall. That’s one of the most well accepted facts in all of physics. This has been a well-established empirical fact for well over 300 years now. A great deal of what happens in nature is based on this fact.

Three hundred years ? That is it ? You are right, humanity has never been known to be wrong for 300 years. Has sir Isaac Newton visited outer space perhaps to test the validity of his theories on classical mechanics ?

Quote
The topic of this thread is how thrust affects a rocket. The opening post was off off about all of this. We (or at least I) corrected him.

And right you did.

Quote
It should have been obvious to him that if he were right then all the rockets we've used to explore space would never have worked. The space shuttle wouldn’t have been able to do all the things that we know that it did, we'd never have been able to send probes to Mars and most of the other planets in the solar system and we’d never have a Global Positioning System (GPS) that many people use nowadays.

These postulates are all part of my assumption.

The SCN presents all the major components of what can be defined as religion. Man lives among the gods (Jupiter, Pluto, etc.), human colonization of other planets will guide mankind to salvation, satellites will save us, etc.

Quote
Then we were insulted for our efforts with the claim that all cranks use, i.e. that we're all brain washed and can't think for ourselves, which is utter nonsense.

I thoroughly agree with your statement. You are among some of the brightest and most stimulating human beings on the planet, and true heirs to Thales of Militus.

Quote
Part of a physicists training is lab work where we experimentally explore what we learn in class. So we aren’t merely told these things but are expected to observe them in the laboratory for ourselves.

PmbPhy , are you familiar with Aesop's fable The astronomer who fell in a well ?

The ending concludes as below :

"Hark ye, old fellow, why, in striving to pry into what is in heaven, do you not manage to see what is on earth ?"
 

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Re: thrust does not work in space
« Reply #99 on: 25/06/2014 05:23:43 »

 

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