Does Rocketry Work beyond Earth's atmosphere?

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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby kickstones on December 4th, 2017, 1:19 pm

More on solar radiation......

PREDICTING THE STRENGTH OF LEONID OUTBURSTS
https://leonid.arc.nasa.gov/MS033.pdf
LYYTINEN AND VAN FLANDERN

152
3.1. THE REGULAR RADIAL PRESSURE

What is usually called simply radiation pressure is here called “regular radial pressure”. It is a repulsive force, which is inversely
proportional to solar distance, effectively lowering the gravitational force. Other radiation pressure effects can be non-radial and can
have a different dependence on solar distance. Notably, variations in radiation force as a result of the particle's surface to mass ratio, rate
of rotation, etc., will lead to dispersion of particles,

The radiation force on a particle consists of three parts: due to absorption of solar radiation energy, due to re-radiation of the thermal energy, and due to reflection (scattering). The radiation pressure force on a totally absorbing particle of diameter d, neglecting the other two effects, at a distance r from the Sun is:

xxxxxxxxxxxxxx
(apologies due to formating problems I cannot post the formula in its entirety at present, interested readers should go to page 152 on the link below)
https://leonid.arc.nasa.gov/MS033.pdf

The constant S0 is the solar radiation constant at Earth’s distance and c is the light speed. In the ideal case where there is no absorption and all the energy would be reflected directly backwards (to the Sun) like a flat mirror put normal to the solar radius, the total effect would be twice that given by (1). Similarly, in the ideal case that all the energy would be re-radiated as thermal radiation directly backwards toward the Sun, the force by re-radiation would be the same as that of scattering. Hence, if the particle is non-rotating, spherical, non-conducting and homogenous on its surface, we can assume that the total force due to absorption, re-radiation, and scattering is directed away from the Sun and obeys an inverse square law.

Another scientific model can be found here...

https://ntrs.nasa.gov/archive/nasa/casi ... 004068.pdf
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
Technical Memorandum 33-494
Mathematical Model of the Solar Radiation Force and Torques Acting on the Components of a Spacecraft
R. M. Georgevi

Although based on forces acting on a spacecraft it may help determine what forces would act on a body of water to ice transformation in space.

ABSTRACT
Solar radiation pressure exerts a mechanical force upon the surface of a spacecraft which intercepts the stream of photons coming from the
Sun. For high-precision spacecraft attitude control and orbit determination, it is necessary to generate a precise mathematical model of the
solar radiation force and the moment of that force; such a model must be more accurate than the currently used "flat surfaceIt model, based
on the radiation force on the effective cross-section area of the irradiated body. Another advantage of the model is that it can be used for the
effects of the air drag, solar wind, etc.


And of interest is ....

https://www.the-cryosphere.net/10/2541/ ... 1-2016.pdf
Reflective properties of white sea ice and snow
Aleksey Malinka et al

Who inform that.....

There can be different contaminants in ice. The particles of sediments from the atmosphere, which could be both long-distance-transferred (as with Sahara dust) or local (pollutionfrom industrial centers), can affect the sea ice albedo drastically (see e.g., Light et al., 1998; Marks and King, 2014; Lamare et al., 2016). For example, clay, slit, and sand particles are found in the ice situated far from a coastline in the Beaufort Sea (Reimnitz et al., 1993) and in the central Arctic (Nürnberg et al., 1994)

This raises the question what would happen if water released from a rocket in space containing such sediments collided with space dust, such as from a comet?

Because as this paper puts forward ...

Space Dust Collisions as a Planetary Escape Mechanism

http://online.liebertpub.com/doi/abs/10 ... alCode=ast

Abstract
It is observed that hypervelocity space dust, which is continuously bombarding Earth, creates immense momentum flows in the atmosphere. Some of this fast space dust inevitably will interact with the atmospheric system, transferring energy and moving particles around, with various possible consequences. An interesting outcome of this collision scenario is that a variety of particles that contain telltale signs of Earth's organic story, including microbial life and life-essential molecules, may be “afloat” in Earth's atmosphere. The present study assesses the capability of this space dust collision mechanism to propel some of these biological constituents into space.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby kickstones on December 5th, 2017, 12:08 pm

Would using seawater in a rocket in space have any benifits?

If this information posted on Wikipedia regarding water rockets is veryfiable then yes.

Image

A water rocket is a type of model rocket using water as its reaction mass. The water is forced out by a pressurized gas, typically compressed air.
The bottle is partly filled with water and sealed. The bottle is then pressurized with a gas, usually air compressed from a bicycle pump, air compressor, or cylinder up to 125 psi, but sometimes CO2 or nitrogen from a cylinder.

Image
Simplified animation of how a water rocket works. 1) A bubble of compressed air is added and pressurizes the contents of the bottle. 2) The bottle is released from the pump. 3) The water is pushed out through the nozzle by the compressed air. 4) The bottle moves away from the water because it follows Newton's Third Law.

Water and gas are used in combination, with the gas providing a means to store energy, as it is compressible, and the water increasing the propellant mass fraction and providing greater force when ejected from the rocket's nozzle. Sometimes additives are combined with the water to enhance performance in different ways. For example: salt can be added to increase the density of the reaction mass resulting in a higher specific impulse.

https://en.wikipedia.org/wiki/Water_rocket

Specific impulse

Specific impulse (usually abbreviated Isp) is a measure of how effectively a rocket uses propellant or jet engine uses fuel. By definition, it is the total impulse (or change in momentum) delivered per unit of propellant consumed and is dimensionally equivalent to the generated thrust divided by the propellant mass or weight flow rate. If mass (kilogram or slug) is used as the unit of propellant, then specific impulse has units of velocity. If weight (newton or pound) is used instead, then specific impulse has units of time (seconds). Multiplying flow rate by the standard gravity (g0) converts specific impulse from the mass basis to the weight basis.

A propulsion system with a higher specific impulse uses the mass of the propellant more effectively in creating forward thrust and, in the case of a rocket, less propellant needed for a given delta-v, per the Tsiolkovsky rocket equation.

Rocketry

In rocketry, where the only reaction mass is the propellant, an equivalent way of calculating the specific impulse in seconds is also frequently used. In this sense, specific impulse is defined as the thrust integrated over time per unit weight-on-Earth of the propellant:


Image

where

Image is the specific impulse measured in seconds
Image is the average exhaust speed along the axis of the engine (in ft/s or m/s),
Image is the standard gravity (in ft/s2 or m/s2).

In rockets, due to atmospheric effects, the specific impulse varies with altitude, reaching a maximum in a vacuum. This is because the exhaust velocity isn't simply a function of the chamber pressure, but is a function of the difference between the interior and exterior of the combustion chamber. It is therefore important to note whether the specific impulse refers to operation in a vacuum or at sea level.

https://en.wikipedia.org/wiki/Specific_impulse

Whether or not salt will have an effect on the states (e.g. freezing ) of the emitted seawater in space is another matter.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby patrix on December 5th, 2017, 2:52 pm

kickstones » December 5th, 2017, 12:08 pm wrote:Would using seawater in a rocket in space have any benifits?


I'm getting a bit puzzled by these posts about water rockets, and this one does it since it implies rockets goes to space, which this thread in its very first post demonstrates they cannot. I suggest another thread for this matter.

And a “water rocket” is a pretty bad idea since water is not very compressible and cannot effectively turn into high volume gas through expansion or chemical reaction. The toy water rockets work by recoil. Compressed air forces the water out and the rockets go up ten, twenty meters or so.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby Altair on December 5th, 2017, 6:34 pm

Anyway, I'm inclined to think that LEO sats (but no more than that) could be launched by just ballistic rockets, without need for them to work in the vacuum. I've been googling how it all began, with the Sputnik. If we have to believe Wikipedia, it was launched by a R-7 rocket, which was a missile launcher. Those could deliver some 5 tons to 12.000 km. Taking into account that Sputnik weighed only 45 kgs., maybe it was possible to get more height + momentum so that light objects could be put in LEO.

Now, this leaves open the question of orbital adjustments and of course, transfer to higher orbits (particularly geostationary), which undoubtely require rocket propulsion in a vacuum.

And of course, no way that something as heavy as the space shuttle can make its way above some 20 km or so...
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby FervidGus on December 5th, 2017, 8:17 pm

PART 1

This will be my first contribution, although I have something in the pipeline for ‘The Rise & fall of ISIS’ too.

What follows will be an evaluation of the arguments for why rocketry will not work in a vacuum, as well as looking into misassumptions into the characteristics of the void of outer space as well. It will be made into 4 main parts, this being part 1. Even if rockets work in space, as I believe, this is does not by default lend credence to the warped images we encounter dressed as fact by NASA or whoever else.

I shall start with the first post of this topic, by Boethius:

“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 aas jet”


Part 1 looks at the first point here, concerning Newton’s first law.

“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.”


[The logic here would be consistent, assuming that the force of the gas is indeed zero, although such is not the case]

“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.
(…)
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: (…)”


Again, this is a good set of points that present a fair argument at first glance. But this is where the science stops, as it is incorrectly applied to the behavior of a rocket.

To start with, a rocket is a projectile that propels itself by ‘chucking’ its combustible load from its exhaust in order to move in the opposite direction of the ‘chucking’. If the exhaust may be manipulated, then the rocket is able to move in accordance to the shape of the exhaust manipulation. This is securely known to work for all missiles that work within the atmosphere.

So what about outer space? Wouldn’t free expansion halt the movement of particles as stated by Boethius? Not quite.

Remaining within the context of Newton’s third law, free expansion, and the non-existent push-pull action within a low gravity vacuum, the following explanation is given. All substances have a triple point, where there is a specific temperature and pressure wherein all three phases (solid, liquid, and gas) may exist at the same time. For water, it may sublimate (depending on the atmospheric conditions) or evaporate into a vapor between the temperatures of -50* C and about 350* C under a pressure curve. Depending on what the temperature of the water is, a certain pressure will result in the vapor phase.

Image
URL:http://cubeupload.com/im/Winterabstract/725pxPhasediagramofw.png

In general, gases are highly excited particles that may bounce around the walls of a vessel if a gas is to be contained- it is this very intensity of collisions which determines the pressure of a gas within a vessel. The more particles there are per unit volume, the higher the pressure. Now if you have liquid oxygen in space, it will most probably evaporate into a gas from liquid phases along certain temperatures and pressures. In the case of rockets purportedly used by NASA, liquid oxygen in kept in very cool conditions i.e. -182.7* C.

Now assume that you have an uninsulated, hollow sphere with 1 very small opening, so far sealed up. Inside this sphere is ordinary water, or liquid oxygen, and this sphere materializes into outer space. According to the laws of pressure, the liquid fluid inside will change phase into a gas due to the huge reduction in pressure. And the gas inside this sphere is now at a much higher pressure because it occupies all of the volume within the sphere; the energetic particles are colliding with the walls. Does low gravity affect the Brownian motion? Not at all (relatively)! The gas particles have too much energy to “link” with each other, and it’s unlikely that at the current temperature and pressure that the particles will settle.

So at this point the small hole is opened. The major point of contention is that free expansion will somehow negate the work done by the propellant exhaust of a rocket. According to Wolfram Alpha;

“In 1843, Joule did this simple experiment to show that the internal energy of a gas is a function of temperature, independent of pressure or volume. When the gas in the left sphere initially flows without resistance into the vacuum of the right sphere, no work is performed and no heat is transferred. Thus the temperature remains constant. It is now understood that this result is accurate only for an ideal gas.”


Image
URL:http://cubeupload.com/im/Winterabstract/FreeExpansion.jpg

Now a few things taken from this are that this works best for an ideal gas, Independent of pressure and volume. This snippet can be applied to our sphere: after a period of time, the gas molecules will flow from the sphere via the small hole into the vacuum. There is a difference of pressure to be noted here- the vacuum has very low pressure, whereas the sphere has a much higher one.

So does this apply to the propellant exhaust of a rocket? Let’s see. First let us consider what a rocket does to produce the exhaust propellant. Through the mixing of liquid oxygen and rocket fuel, an explosive chemical reaction occurs to produce products. Now these exhaust products, usually gases, have a significant kinetic energy to them in contrast to the reaction products, which were fed through pipes using pumps etc. Where did this energy originate from? From the enthalpy change of combustion of course! The exothermic reaction, that was combustion, led to the products’ chemical bonds containing less bond enthalpy thus resulting to energy being lost to the system (the environment within the combustion chamber). Under the conservation of energy, this lost energy has to go somewhere. And so much of this energy is transferred to the products via kinetic energy, whereas a lot of also lost through heat, sound, light energy etc.

We have previously seen that Brownian motion of gas particles is not affected by low gravity, nor a vacuum; a vacuum neither pushes nor pulls. So this also applies to a rocket’s exhaust propellant. This high temperature, energetic exhaust is kept at high pressure by forcing it through a narrow pipe until it reaches the nozzle. Here it bursts out, pushing against the rocket. According to the third law of motion, as it pushes against the rocket, the rocket pushes back, and so the rocket is propelled. Free expansion plays no part here because this is a situation where the gas has a velocity component; it (the exhaust) is not isolated within a vessel with a small hole to pass through, rather it has been formed via a violent reaction and is being channeled to exit the rocket. I can find no scientific basis for other comments on free expansion that were mentioned in the first post of the topic. There is little difference between the process here taking place on earth, or in space.

So in summary, as the exhaust gases exert an upwards force on the rocket, an equal but opposite force downwards is exerted by the rocket body, thus resulting in the desired upwards motion. Neither free expansion nor an atmosphere plays a major role in this key model.

As long as the key points in part 1 are understood and stand without error, then I will progress to the successive parts relating to points 2, 3, and 4.

I will create the following parts soon, and in the meanwhile gladly anticipate debate on this.

(EDIT: Note for the admins: I have used cubeupload for the images, and used the share link URL...which after posting seems to have failed)
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby Flabbergasted on December 5th, 2017, 8:49 pm

FervidGus wrote: ...it (the exhaust) is not isolated within a vessel with a small hole to pass through, rather it has been formed via a violent reaction and is being channeled to exit the rocket...

Not easy to picture.

Does your explanation differ from or coincide with NASA´s? If the first, in what regards?
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby FervidGus on December 5th, 2017, 9:13 pm

Good point. That sentence was a bit too vague.

I will use this V2 rocket cross section as it is quite simple to see the combustion chamber. Now unlike the free expansion diagram I provided, within the V2 the exhaust propellant is exiting via the combustion chamber, which itself has tubes leading to it from the pumps and fuel tanks.

Image
URL:http://cubeupload.com/im/Winterabstract/v2rocket.jpg

Hence the combustion chamber is not an isolated space to demonstrate Joule Expansion under ideal conditions for an ideal gas. The shape is engineered for the optimum transfer of “pushing energy” between the exhaust and rocket by the time it leaves the nozzle at the bottom.

The fact that the chamber is open to the vacuum hardly affects Newton’s Third Law. The vacuum most visibly affects the exhaust shape, and this is something that will be discussed later on.

Does it differ from NASA's explanation? Hmm. This scant summary I've provided, of quite an exciting field of engineering, is within the public domain. I believe nobody as such can alter the bare facts of which I've tried to present in a clear order within these posts. My reading into rocketry is quite conventional- through online .edu resources and classes I remember from college. So if it does coincide with NASA's explanation or appears to have elements missing, it may be the case that they gloss over certain concepts- maybe just for brevity of time as they try to present themselves as communicators of science and engineering.

(Edit: Spelling)
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby Flabbergasted on December 5th, 2017, 9:42 pm

FervidGus wrote:I will use this V2 rocket cross section as it is quite simple to see the combustion chamber.

The V2 (if it ever really worked) was engineered to fly in the atmosphere, pushing against the air. So, either it´s a bad example, or you are saying the exact same technology would work in the vacuum of space, at near-zero gravity.

FervidGus wrote:The fact that the chamber is open to the vacuum...

The possibility of having a combustion chamber open to the vacuum was dismissed further back in this thread. If you think it was wrongly dismissed, please explain why.

I would still appreciate an answer to the question in my previous post. It would help understand your argument.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby FervidGus on December 5th, 2017, 10:15 pm

This reply may unintentionally dip into content meant for the later parts, but this shouldn't be too much of a problem.

Is the V2 a bad example? Used as a model, no. Ignoring its alleged wartime career successes and losses, given enough fuel to facilitate thrust, a missile/rocket is able to reach space. How you may ask? The answer is that air in the atmosphere plays an inconsequential part in the flight of a rocket or missile. The primary means of propulsion for a rocket (in context of part 1) is through application of Newton's Third Law; the faster the rate of 'chucking' exhaust propellant, the greater the velocity of the rocket as the 'pushing' forces are greater.

Air is needed for propulsion where air itself is pushed against. A propeller utilizing vehicle comes to mind, such as a boat (which pushes against water) or light propeller plane.

I can find no evidence to support the idea that rockets or missiles must be used within an atmosphere containing air. So by extension, yes, theoretically the V2 may work at low pressures where there is little air- again, the absence of air and low pressure serves little importance in propelling a rocket.

As for the having such a chamber open to the vacuum, this too is not much of a problem. On Earth, as soon as the pumps activate in transporting reactants to the reaction chamber, then there might be some loss of reactants as they exit via the nozzle due to gravity. This counts as wastage and wastage ceases as soon as combustion is initiated, because reactant materials are being used positively.

Assuming a rocket is started in space, it is possible that similar wastage may occur in a low gravity environment. But considering how a vacuum in space does not pull or push unsecured fluids, then wastage is certainly not going to occur because the reactants or products were somehow "dissipated" into space. A chemical reaction such as combustion is unaffected by low gravity or a vacuum assuming all the needed products are present.

The case against the open chamber cited the action of free expansion. This is a concept that is not strictly relevant to rocketry in space. Why? Because combustion is the primary source of energy for propelling the rocket due to Newton's Third Law, whereas Joule expansion describes the behavior of an ideal gas to spread into a vacuum assuming temperature does not change. It is a process relating to entropy and as so far as to link it to rocketry, the only similarity I can admit to is that a rocket simulates extreme entropy by creating more disorder; the products may be "more" in number than the reactants.

I apologize for the earlier incomplete message. I amended it as soon as I reread your original reply.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby rusty on December 6th, 2017, 9:39 am

After watching the following video I've been thinking about the theoretical possibility of rockets in a (supposed) vacuum again, and my conclusions are somewhat in line with the explanations of FervidGus, I guess.


full link: http://www.youtube.com/watch?v=76JM03a6WH4

I try to put this a little bit more graphical:
Image
Consider the scenario of a confined bomb, carrying all the ingredients needed for explosion, in a vacuum. Ignore for a moment that the fuse would not ignite without air, it may be replaced by some detonator within the confined space of the bomb. What do you think will happen?

a) Nothing. If the bombshell cracks open at all, the gases are sucked out into the vacuum immediately
b) The bombshell will explode and the fragments are thrown into the vast endlessness of outer space, but there is not enough push to even move the passenger. Maybe he'll get some splinters up his ass.
c) The bombshell will explode and push the bombshell fragments and the passenger further into the void at full throttle

If you think that a) will happen, go watch A bomb that can't explode or pursue some other pastime of your liking.

Now attach the bomb to the end of a rocket. That's basically what has been demonstrated in the video above to work in a vacuum chamber:
Image
So, if you'd succeed in firing a series of explosions at the tail of rocket, yes, I think this would propel the rocket into space. The question is: Is this the way rocket motors are supposed to work? Is it necessary for the valve to close between the explosions within the combustion chamber?

This does not take away from my thinking that probably a real vaccuum does not exist and there is no such thing as "outer space". Even if it exists, no one ever got there. The "slow" rockets launched from Kennedy Space Center and elsewhere are probably vertical take-off blimps (airships) with attached rocket or jet engines.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby Altair on December 6th, 2017, 1:11 pm

Anyway, I think it could be much, much simpler than that. Forget about Joule-Thomson, Newton's third law & so on. It's more than enough with the 2nd law.
If we want to accelerate a solid body, we must apply a force upon it. Period.
In a rocket, the only places where we can do that are the nozzles, and to a lesser extent, the combustion chamber. And the only way a gas can exert a force upon a solid body is by means of its PRESSURE. We can give a hoot about temperature and energy of exhaust gases, because all that matters is the gas pressure in the nozzle and combustion chamber. More precisely, its longitudinal component, because the horizontal forces get neutralized between themselves. So the question boils down to: "Is it possible to maintain a sufficient gas pressure for propulsion in the nozzle under vacuum conditions?"

I'll elaborate on this later, as now I'm writing in my tablet and this is slow as molasses, but I hope I've expressed at least the stub of the idea.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby kickstones on December 6th, 2017, 1:43 pm

patrix » December 5th, 2017, 2:52 pm wrote:
kickstones » December 5th, 2017, 12:08 pm wrote:Would using seawater in a rocket in space have any benifits?


I'm getting a bit puzzled by these posts about water rockets, and this one does it since it implies rockets goes to space, which this thread in its very first post demonstrates they cannot. I suggest another thread for this matter.

And a “water rocket” is a pretty bad idea since water is not very compressible and cannot effectively turn into high volume gas through expansion or chemical reaction. The toy water rockets work by recoil. Compressed air forces the water out and the rockets go up ten, twenty meters or so.


Patrix, the title of the thread is 'Does Rocketry Work beyond Earth's atmosphere?' it does not specify what type of propellent a rocket has to use to get it to work in space. I asked the question would a water emitting rocket work in space? based on laboratory experimental data namely that water freezes in a vacuum.

http://www.youtube.com/watch?v=UG7nsZkVZc0

full link: http://www.youtube.com/watch?v=UG7nsZkVZc0

And if replicated by a rocket emitting water in the so-called vacuum in space would this result in the same resulting water to ice transformation thus giving mass for following saltwater emitted to react against, along with solar radiation / wind and dust particles from past comet distribution.

We know comets exist because people have witnessed them long before NASA came along and NASA informs us that the ice surrounding the comet re-acts much the same way as that of rocket boosters.

Therefore suggesting if ice is formed by the water emitting rocket and a similar took place it would help maintain momentum of the rocket in the vacuum of space whereby it is stated 'In rockets, due to atmospheric effects, the specific impulse varies with altitude, reaching a maximum in a vacuum.'

Now I am sure that a mere layman on Cluesforum such as me is not the only person to consider these thoughts, especially if as been suggested in this thread that gases emitted by conventional rockets will not work in the void of space and even if they did it still might be worth looking at other models such as the idea of water based rockets beyond the earths atmosphere for they could be more efficient than present models, seawater would be monetary efficient at the very least.

From Quora.....

https://www.quora.com/How-much-does-NAS ... ocket-fuel

Stats for the space shuttle according to a 2001 NASA fact sheet:

NASA bought hydrogen at 98 cents per gallon. A gallon of liquid hydrogen weighs 0.2679 kg, so they paid $3.66 per kg for liquid hydrogen.

NASA bought oxygen at 67 cents per gallon. A gallon of liquid oxygen weighs 4.322 kg, so they paid $0.16 per kg for liquid oxygen.

Total amounts for those interested:

384,071 gallons of liquid hydrogen in the external tank of the shuttle, for a cost of $376,389.58. ~141,750 gallons of liquid oxygen for a cost of $94,972.50. The total cost of all propellant for "rocket fuel" is $1,380,000. These numbers exclude the hydrogen and oxygen used for cooling, etc.

Sources:
http://www.uigi.com/o2_conv.html
http://www.uigi.com/h2_conv.html
http://www.google.com/url?sa=t&r...

This begs the question why did not NASA carry out their Project High Water at higher altitudes than the two at 105 km (SA-2) and 165 km (8A-3)?

An Analysis of the Second Project High Water Data
https://ntrs.nasa.gov/archive/nasa/casi ... 078055.pdf

Image

Why not carry out the release of water at outer limits of the thermosphere or wherever the void of space is, surely more valuable information would have been obtained than to the official explanation 'what would happen to an aborted rocket payload.'

And if this was the real reason for the experimental data why was regular rocket fuel not used?

Could it be as Boethius pointed out on the first page.....

"Yes, Simon. Tom Wolfe's book "The Right Stuff" documents high altitude flight tests with rocket powered aircraft that would invariably fail in the thin air and plummet back to earth. Chuck Yeager almost died in a NF-104A rocket plane failure while attempting to set a height record. These planes were liquid fuel rockets and not air-fed jets.

Why would NASA claim to be able to send rockets into space when the USAF couldn't get the same technology into even the upper atmosphere?

Why did Chuck Yeager not join the space program? Did he know it was a hoax?"


Did NASA carry out the High Water experiments because it wanted to see if the rocket water to ice momentum scenario would work however the environmental conditions were not favourable and it failed and the official explanations for them taking place were a guise because they were hardly likely to tell the public the real reason behind the experiments.

Which, if so, leads me to postulate that, yes, rockery can work beyond the earths atmosphere it's just we cannot, as yet, get there.

Anyway Patrix I must correct you on the statement..

Compressed air forces the water out and the rockets go up ten, twenty meters or so.


Class A Single Stage Altitude Record

Ascension III Launching to a new world record altitude. Image
Ascension III Water Rocket launching to a new world record altitude.
Stuart Swan - UCT
Ascension III
2723 Feet. (830m)
August 26, 2015


Class C Flight Duration Record

The rocket that holds the flight duration world record. Image
[D&P]Rockets*
Project 1.5
1.47 min

http://wra2.org/WRA2_Standings.php

I wonder what the duration would be in the void of space and less gravitational pull?
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby simonshack on December 6th, 2017, 2:06 pm

Dear FervidGus, you wrote:

FervidGus wrote:The answer is that air in the atmosphere plays an inconsequential part in the flight of a rocket or missile.


Next time you submit such radical opinions of yours, please type "In my opinion..." in front of your sentence. You see, kids may be reading this forum - and we do not wish to contribute to the Nutwork's ongoing 'dumbing-down' programme. Btw, what is inconsequential to me is the above opinion of yours - since it is, quite frankly, absurd.

FervidGus wrote:The primary means of propulsion for a rocket (in context of part 1) is through application of Newton's Third Law; the faster the rate of 'chucking' exhaust propellant, the greater the velocity of the rocket as the 'pushing' forces are greater.


Yes, we have heard that one before - a million times, in fact - thank you very much. You know, this is precisely what NASA (et al) keep telling us. They also say that their rockets all expend their fuel within 3 minutes (or less) of being launched. Now, in your (best) opinion, what exactly will the rocket be 'chucking out' - once it runs out of fuel? A payload of medicine balls, perhaps? It is my (best) opinion that a rocket will plummet back to Earth - as soon as its fuel is exhausted. Does this opinion of mine sound wacky to you?

Image < (NASA's favorite 'explanation' for how rocketry works)

See, what we are actually discussing here is the feasibility of launching a rocket beyond 100 km of altitude (the so-called "Karman line") and keep it hurtling across space at hypersonic speeds for days, months, years - or even decades (as we are told most satellites and Space Stations do). Thus, unless you have - for some reason - elevated in your mind Newtons's cannonball thought experiment to some sort of real-world physical possibility, your hitherto-submitted opinions on this matter are, you may admit, no more than thin air. The problem is: a thought experiment is no more than a thought experiment. What we are being told (as fact) is that thousands of man-made machines are currently revolving at hypersonic speeds around Earth - solely by virtue of their initial 3-minute "push" into space. I think that our readers are more interested in your opinion about this outlandish "fact" (peddled by NASA et al) - rather than any disquisitions about how 'chucking out matter out of a rocket' could theoretically propel the same, by virtue of recoil forces only, without the need to push against air (which is, of course, the primary force that propels any man-made rockets / or fireworks within our atmosphere).
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby patrix on December 6th, 2017, 2:50 pm

Important things deserve to be repeated and I feel a responsibility since I opposed the idea of rockets not working in vacuum not long ago, before I was able to mentally grasp the basic physics involved. Let me try to explain this in some new ways, but also PLEASE go back to the beginning of this thread and start reading, researching and thinking. All you really need are in those very first posts by Boethius et. Al.

Think of the atmosphere as a sea. In a sea, we have a sea bottom where the pressure is high because all the water above and we have the shallows where the pressure is low. Then there is the water surface where the water ends and another element begins that we call air. This element actually contains a lot of water also but in gas form and there is less water the higher we get.

So if we view the atmosphere as a “sea of air”, then we call the waterline of that sea the Karman line. That is where the shallows of our air sea ends and where another element begins. It was previously called the Ether but then Einstein and other gods of science saw it fit that this element should not have a word, so today we refer to it as the vacuum of space, which can be argued wrong since vacuum strictly means something entirely void of matter, but for practical reasons I use that word.

With this in mind we go to the laws of physics. Newtons laws of motion and fluid dynamics in particular. Fluid dynamics is about how fluids and things in fluids behave and gas is also a fluid here.

A boat and a fish moves by moving the surrounding water. And if we lift them out of the water they will not move anymore because their way of creating motion through their interaction with the surrounding molecules is not something that works when they are in gas form.

A bird, a plane and a rocket, moves by moving the surrounding air. And if we lift them out of the surrounding air they will not move anymore because their way of creating motion through their interaction with the surrounding molecules is not something that works if those molecules are not present.

Newton need not apply here since the first law stipulates that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force.

In the case of rocketry it might be a bit harder to understand how that external force is created since they don’t have a propeller or flap their wings but you can think of it this way – When we throw a rock into water we get an “up burst” in lack of a better word. This is because the rock moves the water to the sides and then the water rushes back creating a pressure wave. This is also how rockets gets their thrust in the air. The hot gasses from the rocket pushes away the air and when it rushes back it propels the rocket forward.

It might be the case that rockets are more efficient in thin air compared to jet engines because of their different way of creating thrust, but its clear that they have no way of working without air entirely.
Last edited by patrix on December 6th, 2017, 4:03 pm, edited 3 times in total.
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Re: Does Rocketry Work beyond Earth's atmosphere?

Postby Flabbergasted on December 6th, 2017, 3:27 pm

FervidGus wrote:...given enough fuel to facilitate thrust, a missile/rocket is able to reach space...
...air in the atmosphere plays an inconsequential part in the flight of a rocket or missile...
...a chemical reaction such as combustion is unaffected by low gravity or a vacuum...

Simply saying something does not make it so. Have you at all read Simon´s analysis of NASA´s claim that rockets do not push against anything, even when they are hovering over the launch pad?

FervidGus wrote:...combustion is the primary source of energy for propelling the rocket due to Newton's Third Law...

Of course combustion is the primary source of energy for propelling a rocket, but that doesn´t tell us how or whether Newton´s laws can be applied to rocket propulsion in space.

Your reasoning is circular and the conclusions are not supported by the premises.
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