To add comments or start new threads please go to the full version of: Can Moon Ice Provide Rocket Propulsion?

conklin
The simplicity of the basics of mechanical engineering and rocket propulsion
is untaught and rarely discerned in 2009.

On May 25, 1961, JFK told us to go to the Moon.
On July 20, 1969, we landed on the Moon.
The job took 9.16 years starting from scratch.

1961 TECHNOLOGY STATUS:
Jet aircraft were starting to come into commercial use.
In 1966, NBC became the only color TV network.
In 1969, there were no push-button phones, fax machines, integrated circuits, "chips", LCDs, personal computers, or hand calculators. Mechanical desk calculators could only add, subtract, multiply, and divide.
A room-size IBM computer used punch-card input and printed-paper output
and had the power of a 386.
Most engineering calculations were made with a slide rule which gave 3 significant figures and no decimal point. Engineering in the 1960's was simple.

ENGINEERING DIMINSIONS:
In all of mechanical engineering there are only 4 basic dimensions.
The 4 dimensions are Distance, Force, Time, and Temperature.

UNITS OF MEASUREMENT (Pardon my English units from the 60's):
The basic dimensions of Distance, Force, Time, and Temperature
need only to have units of Feet, Pounds, Seconds, and degrees F.

A conversion table may have 1,000 conversion factors, but every variable from "acres" to "watt-hours" can be expressed in units of Feet, Pounds, Seconds, and degrees F.
A thousand conversion factors are unnecessary.

There is nothing in mechanical engineering and rocket propulsion that cannot be expressed in units of Feet, Pounds, Seconds, and degrees F.
If these units (and only these units) are used, formulas and equations become simple to verify by dimensional analysis, and common error sources are eliminated.
Many variables would be expressed in decimal fractions, which are awkward in conversation, but not for computer calculations.

The above is true for the metric system, which needs only units of
Meters, Newtons, Seconds, and degrees C to measure anything.

Note: Mass is not a dimension. Mass does not need a name or a unique unit of measurement. Mass is simply the weight of something on Earth divided by the gravitational acceleration on Earth per Newton's equation F = ma.
Thus, m = W pounds / 32.2 foot/sec^2 = pound-sec^2 / foot.
Simply use Weight in pounds divided by 32.2 to get Mass.

ENERGY, HEAT, and WORK:
These all have units of Foot-Pounds. Work is Force applied over a Distance.
There are always energy losses when energy is changed from one form to another. Even without friction and heat losses, there is additional unavailable energy
when heat is converted into work.
The unavailable energy (entropy) of the universe always increases.

POWER:
Power is the rate of energy, heat, and work.
Power has units of foot-pounds / second.

CONSERVATION OF MECHANICAL ENERGY:
In a closed system, the total of all forms of mechanical energy remains constant. The mass within a closed system can contain heat energy due to temperature (F), potential energy due to elevation (Feet), and kinetic energy due to speed (Feet/Second). All the forms of energy can change from one form to another,
but the total energy remains constant.

CHEMICAL ENERGY AND ROCKET PROPELLANT:
Most rocket propellant contains chemical energy which provides the heat energy
to accelerate its own mass to a supersonic speed producing rocket thrust.

Monopropellant such as N2H4 disassociates into N2 and H2 plus heat.

Bipropellant such as cryogenic liquid H2 and O2 combine into H20 plus heat.
H2 is the fuel and O2 is the oxidizer.

Solid propellant such as (NH4)2S2O8 (oxidizer} held together with a plastic binder and aluminum fibers (fuel) combine to form products of combustion plus heat.

PRODUCTS OF COMBUSTION:
The molecular weights of H2 (2) and O2 (32) indicate that 2 pounds of H2 combine with 16 pounds of O2 to form 18 pounds of H2O. One pound of rocket fuel requires 8 pounds of oxidizer to form 9 pounds of high temperature propellant gas.

ROCKET THRUST:
Google rocket thrust and you may find a complicated mathematical definition.
Think about rocket thrust and it is simply the unbalanced rocket chamber pressure times the nozzle throat area... F pounds = (Pc pounds / foot^2)( At foot^2).
If a supersonic (divergent) nozzle is used to accelerate and expand the exhaust gas to the ambient static pressure, an additional 40% increase in thrust is achieved.
This is called the Thrust Coefficient, Cf. Thus, F = (Pc)(At)(Cf) pounds.

PROPELLANT EFFECTIVENESS:
Propellant effectiveness is measured by its Specific Impulse (Isp).
Specific Impulse = (rocket thrust) / (pounds propellant / second).
Thus, Isp = (pounds) / (pounds / second) = seconds.

PROPELLANT IMPETUS:
Propellant Impetus is the measured Work that a pound of propellant can perform.
In 1252, Friar Roger Bacon of England wrote an essay describing the Chinese formula for gunpowder. By 1600, cannon were perfected to the point where few changes were made for 300 years. During that time, fixed fortifications realized
that it was necessary to test the impetus of their gunpowder in order to calculate
range vs. elevation for their cannon as follows...

A small vertical mortar was located beside a tall pole graduated in feet.
A measured weight of gunpowder propelled a measured weight of cannon ball
up along the pole. The person assigned to "keep your eye on the ball"
recorded the height of the ball (gunpowder Impetus) in feet.

But I digress.

Can Sub-Surface Moon Ice (-230C) Provide Rocket Propulsion?

I would like someone from from NASA to explain exactly how.

James T. Conklin, P.E.
RobDegraves
That was a long and rambling post for a simple question that you could have looked up yourself.

QUOTE
Can Sub-Surface Moon Ice (-230C) Provide Rocket Propulsion?

Ice = water

Water = H20

Liquid oxygen and liquid hydrogen are used in the space shuttle and various other rockets, particularly in the upper stages.

H = Hydrogen
0 = Oxygen

Do you really need someone from NASA to explain this?

light in the tunnel
I read this post once and just skipped it because I didn't have a clue.

Suddenly it occurs to me that just a couple months ago, people were discussing whether moon water would be abundant enough not to have to ship it at extreme cost from Earth.

Now you want to burn it as fuel? I don't know how much ice is projected to be available on the moon at this point, but my guess would be that it is still scarce enough that you'd really have to conserve it for basic living necessities like drinking and growing food.

Luckily someone came up with a way to shower using sound waves. Hmmm, wonder why I haven't heard anything about that since going green became popular?
conklin

THANK YOU RobDegraves! TOGETHER WE CAN DO THIS!

All that is needed to produce cryogenic liquid hydrogen fuel
plus 8-times its weight of cryogenic liquid oxygen oxidizer
ON THE MOON; to be used as exothermic rocket propellant
from dirty, sub-surface, polar Moon-Ice at -230C (-382F)...

Is my patented Mk 2 Mod 4 portable, compact, light-weight,
free-standing, catalytic, solid-phase-water disassociater;
plus the appropriate transfer pumps and liquid storage tanks.
RobDegraves
QUOTE
All that is needed to produce cryogenic liquid hydrogen fuel
plus 8-times its weight of cryogenic liquid oxygen oxidizer
ON THE MOON; to be used as exothermic rocket propellant
from dirty, sub-surface, polar Moon-Ice at -230C (-382F)...

Sheesh.. if it's hard it's impossible?

1. You pointed out it's cold on the Moon... so cryogenic won't be so tough to do.

2. Extracting largely depends on where it is and in what concentration. That remains to be seen.

3. You need water and you need energy. If you are willing to go nuclear it's not that hard.

To be honest, I don't see the point of all this. It's theoretically possible so it can be done. However, whether it will be done is subject to a thousand variables including cost, benefit and political desire.

Did you actually have a point?

conklin

CAN LIQUID HYDROGEN & LIQUID OXYGEN BE PRODUCED FROM MOON-ICE?

RobDegraves justifiably dismissed using the catalytic water disassociater.
Although the Mk 2 Mod 4 solid-phase water disassociater was a complete failure
during initial demonstration tests on neat water-ice at 0C, it is anticipated that
performance will be worse on ice crystals entrapped in Moon rocks at -230C.

RobDegraves advocates that we "go nuclear it's not that hard".
I assume that Degraves' approach is to fly a nuclear reactor to the Moon
to disassociate ice crystals into cryogenic liquid hydrogen and liquid oxygen
using "heat energy" as he stated above.

I t should be noted that the initial testing using the Chernobyl nuclear reactor
resulted in the conversion of the neat water reactor coolant into high-pressure
super-heated steam which exploded the containment vessel and resulted in
the catastrophic melt-down of the nuclear reactor core.

It became obvious at that time that water cannot be disassociated with
"heat energy" from a nuclear reactor.

From an engineering standpoint, the answer to the question is: NO!

RobDegraves
So... science.. have you ever heard of it?

The first principle is... you can't just make stuff up.

QUOTE
Mk 2 Mod 4 solid-phase water disassociater

Didn't Marvin the Martian have something like that?

Other than that.. I have no idea what you are talking about.

QUOTE (->
 QUOTE Mk 2 Mod 4 solid-phase water disassociater

Didn't Marvin the Martian have something like that?

Other than that.. I have no idea what you are talking about.

I assume that Degraves' approach is to fly a nuclear reactor to the Moon
to disassociate ice crystals into cryogenic liquid hydrogen and liquid oxygen
using "heat energy" as he stated above.

Sigh...

Nuclear reaction produces heat. Heat makes ice water, then steam. Steam makes electricity. Water from ice gets split using electricity.

Really really basic stuff.

QUOTE
I t should be noted that the initial testing using the Chernobyl nuclear reactor
resulted in the conversion of the neat water reactor coolant into high-pressure
super-heated steam which exploded the containment vessel and resulted in
the catastrophic melt-down of the nuclear reactor core.

You do realize that there are thousands of nuclear reactors that operate just fine right?

QUOTE (->
 QUOTE I t should be noted that the initial testing using the Chernobyl nuclear reactorresulted in the conversion of the neat water reactor coolant into high-pressuresuper-heated steam which exploded the containment vessel and resulted inthe catastrophic melt-down of the nuclear reactor core.

You do realize that there are thousands of nuclear reactors that operate just fine right?

From an engineering standpoint, the answer to the question is: NO!

Do you have any idea what you are talking about? NO!

Capracus
QUOTE (RobDegraves+Oct 30 2009, 10:11 PM)
Sigh...

Nuclear reaction produces heat.  Heat makes ice water, then steam.  Steam makes electricity.  Water from ice gets split using electricity.

Really really basic stuff.

You do realize that there are thousands of nuclear reactors that operate just fine right?

Do you have any idea what you are talking about?  NO!

Maybe it would help if you replied in crayon .

To further complicate the discussion for conklin:

Uranium Found on the Moon
http://www.space.com/scienceastronomy/0906...anium-moon.html

conklin

Stay on the topic of the Post, which should remain the topic of discussion:

CAN LIQUID HYDROGEN & LIQUID OXYGEN BE PRODUCED BY MEN
AND MACHINERY FROM SUB-SURFACE ICE CRYSTALS ENTRAPPED
IN MOON ROCKS LOCATED IN THE POLAR REGIONS OF THE MOON
WHERE THE MOON SURFACE TEMPERATURE IS -230C (-382F)?

RobDegraves wrote:
"Nuclear reaction produces heat.
Heat makes ice water, then steam.
Steam makes electricity.
Water from ice gets split using electricity."

After several helpful and constructive replies, she has finally mentioned
the word "electricity". The word that I was attempting to bring into the
topic of discussion (using some satirical humor) was the word "electrolysis".

So let's get started with the details of doing some electrolysis on the Moon.

First, We need a light-weight integrated portable nuclear-electric-power plant.
The components would include a nuclear reactor, working-fluid heat-exchanger,
a closed-system steam turbine, a steam condensing unit, an electric generator,
electric transmission lines, transformers, a means for reactor cooling,
a means for excess electric power energy dissipation,
and all the associated instrumentation, monitoring, and control equipment.

Second, We need to remove the electric power plant from the surface
of planet Earth and retro it, undamaged, onto the surface of the Moon.

Third, We need to excavate polar ice-crystal-bearing Moon-rock at an
ambient Moon surface temperature of -230C (in the dark), crush the rock,
separate out the ice, and transport the product to the electrolysis unit.

BUT WAIT! THERE IS A MAJOR PROBLEM WITH THE
NUCLEAR ELECTRIC POWER PLANT ON THE MOON!

On Earth, nuclear electric power plants must be located on rivers where there is
an unlimited supply of ambient cooling water. Huge amounts of cooling water
are required to cool the reactor, condense the prime mover steam,
remove unavailable heat, and dissipate unused electrical power.

On the Moon, there is no water for convective heat transfer.
On the Moon, there is no air for convective heat transfer.
On the Moon, there is only inefficient radiant heat transfer into space.

I invite all PhysForum members to help SOLVE the lunar nuclear reactor
cooling problem before I describe the really MAJOR MAJOR PROBLEM,
which I will post as a separate topic.

RobDegraves
Wow... that was ridiculous.

QUOTE
she has finally mentioned

She?

Where do you get that I am a woman? The name Rob? Maybe it means something else where you are from.

QUOTE (->
 QUOTE she has finally mentioned

She?

Where do you get that I am a woman? The name Rob? Maybe it means something else where you are from.

First, We need a light-weight integrated portable nuclear-electric-power plant.

It doesn't have to be lightweight specifically. It just needs to be possible to bring it there.

However, it seems it's being done anyway...

Moon Generator

QUOTE
I invite all PhysForum members to help SOLVE the lunar nuclear reactor
cooling problem before I describe the really MAJOR MAJOR PROBLEM,
which I will post as a separate topic.

The MAJOR MAJOR PROBLEM... is that you don't have any idea of what you are talking about or any knowledge of the subject matter.

You just think you do... which is even worse.

Here's the NASA page on it if you want to actually learn something real.

Nasa page on generator

conklin

RobDegraves: I asked you politely to contribute to the topic,
but you could not resist casting a few more insults as you have in the
majority of your hundreds of replies on PhysForum, which I reviewed.

It is obvious why you do not use or reveal your true full name.
It is apparent that you are a liberal academic snob who has the luxury
of never having to engineer, design, and produce a working product.
Do you hold any patents? I hold three. Have you produced any
beneficial hardware innovations? I have a dozen plus.
Have you presented technical papers at industry conferences? Show me.

To the point... You gave a NASA website to prove something, which only said:

"Our goal is to build a technology demonstration unit with all the major
components of a fission surface power system and conduct non-nuclear,
integrated system testing in a ground-based space simulation facility,"

"Our long-term goal is to demonstrate technical readiness early in the
next decade... "

The NASA lunar nuclear power system DOES NOT EXIST;
The NASA long-term goal is to "demonstrate technical readiness".
The NASA long-term goal is not to design, build, and demonstrate
a practical lunar nuclear reactor electrical power generating system.

I can remember when President Nixon announced that government
funding would be provided in whatever amount it took to cure cancer.

I can remember when President G. H. W. Bush
announced his plan to send men to Mars.

I can remember when Vice-President Dan Quayle, who was
chairman of the National Space Council, announced:

"Mars is essentially in the same orbit [as Earth]....Mars is somewhat
the same distance from the Sun, which is very important.
We have seen pictures where there are canals, we believe, and water.
If there is water, that means there is oxygen.
If oxygen, that means we can breathe."

Confused2
Re:keeping the cold end cold:-
http://en.wikipedia.org/wiki/Black_body#St...93Boltzmann_law

Assuming (arbitrarily) a cold end temperature of 300K .. given that you're radiating into close to 0K I get that you radiate about 500W/m^2 .. not too impractical for (say) a 12kW generator.

-C2.
RobDegraves
QUOTE
Do you hold any patents? I hold three.

Which ones?

QUOTE (->
 QUOTE Do you hold any patents? I hold three.

Which ones?

Have you produced any
beneficial hardware innovations? I have a dozen plus.

Which ones?

QUOTE
Have you presented technical papers at industry conferences?

Have you? Which ones?

QUOTE (->
 QUOTE Have you presented technical papers at industry conferences?

Have you? Which ones?

The NASA lunar nuclear power system DOES NOT EXIST;

That's why they are building it.

QUOTE
The NASA long-term goal is not to design, build, and demonstrate
a practical lunar nuclear reactor electrical power generating system.

Sigh... learn to read.

QUOTE (->
 QUOTE The NASA long-term goal is not to design, build, and demonstratea practical lunar nuclear reactor electrical power generating system.

Sigh... learn to read.

After a one year design and analysis phase, a single contractor will be selected to build and test a prototype power conversion unit. When complete, the power conversion unit will be integrated with the other technology demonstration unit's major components.

Personally, I think you are uninformed and possibly unbalanced.

Lastly....

QUOTE
It is obvious why you do not use or reveal your true full name.
It is apparent that you are a liberal academic snob who has the luxury
of never having to engineer, design, and produce a working product.

Let's be clear. I don't give a fig for your opinion of me. My posts speak for themselves and are judged by others for what they are. What you think of them or me is irrelevant. My academic or professional qualifications are not yours to estimate nor does your opinion mean anything to me as it cannot affect me in any way... either here nor elsewhere.

It's obvious you have no idea what you are talking about and you have yet to demonstrate that I am wrong.

Capracus
QUOTE (conklin+Oct 31 2009, 10:07 PM)

The NASA lunar nuclear power system DOES NOT EXIST;
The NASA long-term goal is to "demonstrate technical readiness".
The NASA long-term goal is not to design, build, and demonstrate
a practical lunar nuclear reactor electrical power generating system.
A NASA lunar transport system does not exist either, do you see that as a technical obstacle to putting man and material back on the Moon? In the case of transport and power generation, the technology, and to some extent, the hardware already exist. It's all a matter of adaptation and will.
http://www.hyperionpowergeneration.com/

http://nextbigfuture.com/2008/11/large-sca...-power-for.html

Humans likely won't be back on the Moon for another 10-20 years, but in that time, there is no reason to doubt that a practical nuclear power generation system will be sufficiently developed for use on the Moon.
conklin

Some Things Go Unlearned:

1.... At the start of the Apollo Program in 1961, everything was known about
solid rocket motor design, liquid rocket engine design, rocket propulsion performance,
rocket propellant chemistry and internal ballistics that is known today.

2.... The Laws of Motion, Thermodynamics, and Chemistry;
and the Laws of Conservation of Energy, Momentum, and Mass
will not change in time, even for the liberal idealists.

3.... This one cost ME several tens of thousands of dollars. I offer it up for free:
"Understand EVERYTHING about a problem BEFORE starting to work on a solution to the problem."

Number 3 includes manufacturing rocket fuel and oxidizer from non-existent water on the Moon;
by means of electrolysis using electricity generated with heat from a nuclear reactor on the Moon,
where no heat-transfer cooling medium exists on the Moon.
One should start by studying the NASA/Rocketdyne liquid H2/LOX propellant specs.

But, I am just a caveman engineer who was frozen in the ice, dug up, thawed out,
and put to work (with a slide rule) in the aerospace industry in 1962.
adoucette
A Lunar Nuclear Reactor
Tests prove the feasibility of using nuclear reactors to provide electricity on the moon and Mars

http://www.technologyreview.com/energy/23247/

A "significant amount" of frozen water has been found on the moon, the US space agency said Friday heralding a major leap forward in space exploration and boosting hopes of a permanent lunar base.

http://news.yahoo.com/s/afp/20091113/ts_af...encespaceusmoon

Arthur
light in the tunnel
There's nowhere on the surface of the moon that sunlight is always accessible? The polar regions of Earth are more difficult to harness solar energy because sunlight has to pass through a longer distance of atmosphere, which filters out more of the light and therefore energy. But on the moon, without atmosphere, sunlight should be just as strong and energetic in the polar regions as around the equator, right? So shouldn't it be possible to harvest 40kw of photovoltaic electricity all the time there despite the moon's slow rotation?
flyingbuttressman
QUOTE (light in the tunnel+Nov 13 2009, 05:28 PM)
There's nowhere on the surface of the moon that sunlight is always accessible? The polar regions of Earth are more difficult to harness solar energy because sunlight has to pass through a longer distance of atmosphere, which filters out more of the light and therefore energy. But on the moon, without atmosphere, sunlight should be just as strong and energetic in the polar regions as around the equator, right? So shouldn't it be possible to harvest 40kw of photovoltaic electricity all the time there despite the moon's slow rotation?

The polar regions might work, except that the moon's orbit is more eccentric than the Earth's, and the polar regions might be without direct sunlight if the angle was off. I'm not very familiar with the moon's orbital patterns, but I would check this out.

Any solar array on the poles would have to stand on-end to collect the maximum amount of light. This array would then have to rotate 360 degrees over the course of a month to stay in alignment with the sun.
light in the tunnel
QUOTE (flyingbuttressman+Nov 13 2009, 09:39 PM)
The polar regions might work, except that the moon's orbit is more eccentric than the Earth's, and the polar regions might be without direct sunlight if the angle was off. I'm not very familiar with the moon's orbital patterns, but I would check this out.

I read the wiki page on lunar orbit and was more perplexed than I expected. The moon's orbit is not in the same plane as the Earth's around the sun, and the rotational dynamics confused me too. Luckily, there was a nice time-lapse film of the moon as it goes through its phases, and I would dare to say that the polar regions seemed to glow a little bit more than the rest during new moon, but this could be wishful thinking influencing my vision:)

I wish some lunar expert would see this question and have an exact working model of the moon that they could use to directly examine the shortest duration of darkness at any location. That would solve this question a lot more easily.

I think solar panels would be a much more efficient option than nuclear for generating electricity on the moon. After all, you can put up as many solar "sails" as you want and they can be very big with relatively weak support considering the low gravity. Plus it's not like there's wind or precipitation to knock them down.
flyingbuttressman
QUOTE (light in the tunnel+Nov 13 2009, 06:04 PM)
I wish some lunar expert would see this question and have an exact working model of the moon that they could use to directly examine the shortest duration of darkness at any location. That would solve this question a lot more easily.

NASA: Your tax dollars at work. I'm sure someone over there has already figured it out.
QUOTE
I think solar panels would be a much more efficient option than nuclear for generating electricity on the moon.  After all, you can put up as many solar "sails" as you want and they can be very big with relatively weak support considering the low gravity.  Plus it's not like there's wind or precipitation to knock them down.

Please explain why you are using the word "sail" instead of "panel." Solar sails are based on an entirely different concept.
light in the tunnel
QUOTE (flyingbuttressman+Nov 13 2009, 10:11 PM)
NASA: Your tax dollars at work. I'm sure someone over there has already figured it out.

I think I read somewhere that NASA is completely privately funded at this point. Judging from the cost I paid for shiny magnetic rocks for my son, the whole operation is funded by the gift shop.

QUOTE
Please explain why you are using the word "sail" instead of "panel." Solar sails are based on an entirely different concept.

Good question. I just said "sails" because I was thinking about large flexible sheets instead of rigid "panels." I guess the flexible ones can be called "panels" too, but I tend to think of panels as having rigid glass.

I thought that solar "sails" were just panels used to collect energy for space propulsion. Is there actually a type of "solar sail" that gets pushed directly by the impact of solar wind? In that case I would agree that I abused the term.
flyingbuttressman
QUOTE (light in the tunnel+Nov 13 2009, 07:14 PM)
I think I read somewhere that NASA is completely privately funded at this point. Judging from the cost I paid for shiny magnetic rocks for my son, the whole operation is funded by the gift shop.

Uhh, no. Unless some other entity besides the Federal Government can foot the \$17 Billion per year bill, it's going to be federally funded for the foreseeable future. Gift shops price gouge because they know suckers will buy stuff for their kids.
QUOTE
I thought that solar "sails" were just panels used to collect energy for space propulsion.  Is there actually a type of "solar sail" that gets pushed directly by the impact of solar wind?  In that case I would agree that I abused the term.

Solar Sail
PhysOrg scientific forums are totally dedicated to science, physics, and technology. Besides topical forums such as nanotechnology, quantum physics, silicon and III-V technology, applied physics, materials, space and others, you can also join our news and publications discussions. We also provide an off-topic forum category. If you need specific help on a scientific problem or have a question related to physics or technology, visit the PhysOrg Forums. Here you’ll find experts from various fields online every day.
To quit out of "lo-fi" mode and return to the regular forums, please click here.