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Mining the moon for rocket fuel to get us to Mars



 
 
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  #1  
Old May 28th 17, 03:21 PM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,524
Default Mining the moon for rocket fuel to get us to Mars

First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF? So, to build mining
equipment on the moon, you're going to build an entire freaking factory,
from local materials?!?!? So, WTF are you going to use to mine the
materials to build the factory?!?!?!?


Don't get me wrong, I think *eventually* we'll be mining the moon for
water to turn into LOX and LH2 (or possibly methane) to supply a fuel
depot in lunar orbit. But, needless to say, I think the supporters of
this notion are daft if they think it's going to happen in the next 20
years or so by building a freaking factory on the moon that's capable of
building mining equipment that's not JPL class "toys" that wear out
faster than you can build them.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
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  #2  
Old May 29th 17, 08:35 PM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Mining the moon for rocket fuel to get us to Mars

On Monday, May 29, 2017 at 2:21:39 AM UTC+12, Jeff Findley wrote:
First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF? So, to build mining
equipment on the moon, you're going to build an entire freaking factory,
from local materials?!?!? So, WTF are you going to use to mine the
materials to build the factory?!?!?!?


Don't get me wrong, I think *eventually* we'll be mining the moon for
water to turn into LOX and LH2 (or possibly methane) to supply a fuel
depot in lunar orbit. But, needless to say, I think the supporters of
this notion are daft if they think it's going to happen in the next 20
years or so by building a freaking factory on the moon that's capable of
building mining equipment that's not JPL class "toys" that wear out
faster than you can build them.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.


Development is non-linear and results in a technological singularity. Growth is not

y = EXP(t), t=0 to infinity

it is

y = 1/(t-1), t = 0 to 1

Where one is the year 2035AD and 0 is now.

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

The singularity is generally thought of as a time when machines are smarter than people, and this is true, however, it involves more than that. Anything it is physically possible to do, will be doable after this date.

The Delta launcher took 30 years and $60 billion to develop. SpaceX took 15 years and $10 billion. RocketLab took 4 years and $100 million and its present capacity is the capacity of the original Delta space launcher was less than the Electron (RocketLab's launcher). The trend toward more capacity at less cost is obvious. The singularity approacheth.

The discovery of water ice on the poles of Mercury, have awakened many to the possibility that water is a lot more common on rocky planets than previously thought. It seems protons in the solar wind, interact with silicates in the rocky planet to create water and if a rocky planet or moon can hang on to it, that can be accumulated, and used as a propellant resource.

The use of Earth's moon and moons in general as resource bases is energetically very favourable. Not only around Earth, but around Mars. Deimos and Phobos are thought to have lots of water in them as well. Since they have very low densities.

So, finding water is the first step.

An abundance of power is the second step.

In the 1950s this was thought to be nuclear fission power. Today this is most popularly solar power. Tomorrow, it may be nuclear fusion power.

Advanced tooling is the third step.

Again, in the 1950s, specialty equipment was made to transform life on Earth, making all manner of expensive consumer items more cheaply than it had ever been made before.

This requires a lot of expensive tooling be designed fabricated and tested, and then transported. If lightweight enough, it really wasn't a burden for space applications. So, instead of making a million cans of soup a day, or V8 engine blocks, we build highly automated machinery, that's lightweight, operates with a mobile power source, and makes what small groups of individuals need, to make stuff from materials found around it without a lot of labour.

Many social scientists have pointed out that the wars that have been fought throughout the 20th century have really been a reflection of the social conflict between a ruling oligarchy and the vast majority of humanity they have exploited. That is the wars we fight are to keep the tremendous productive capacities from being used to eradicate poverty hunger and want, which is how the ruling elite maintain control. War provides a simple explanation of this, and conveniently absorbs the expanded productive capacities.

One of the benefits of space program of this nature, where the engineers and scientists that brought you everything from contact lenses to soda pop, now turn their considerable skills to producing small self sufficient communities that eke out a living on the moon or asteroids, would have been the advanced tooling to live on the moon, would have benefitted everyone on Earth too.

Vertical farms of today lean heavily on the studies of the 1950s through 1970s space colonies. Had these space colonies been funded at the time, we would likely have licked hunger and starvation as well as poverty, and already have an abundant world of plenty. This would have changed social structure, and even us genetically, without the constant threat of violence a radically new sort of existence opens before us.

https://www.youtube.com/watch?v=0jFGNQScRNY

Since high incomes in a population translate to low birth rates, particularly as women participate equally with men, overpopulation would have been licked by 2000 as well, and will be licked by 2050 in any case.

This was written about by the futurist Herman Kahn in the 1950s and 60s - and was commented upon seriously. Some feel this is why the aggressive space program of the Kennedy Administration was abandoned in favour of the War in Vietnam by the deep state and the ruling oligarchy that runs it. The funny thing is, had they adopted and embraced Kahn's vision of the future (apart from his willingness to engage in nuclear warfare) the oligarchy would have been 'first among equals' in the post singularity age. As it stands, they are growing ever more reviled, and will not likely make it through the singularity unchanged.

Today we have 3D printing, early versions of AI, and the possibility of 'clanking replicators' which reduce the overall cost of the process described above. This permits private companies to do what it took than entire societies to do in the 1950s. So, Elon Musk and others can today make a decision to develop off world colonies and seriously do so.

The long term benefits remain the same, yet the scale of the enterprise is that of a corporate programme, rather than a national programme like a war, or a highway system, or a rail system, so today we see private companies announcing plans that were discussed as a social goals in the 1950s, and we also see the erosion of the power of governments.

Social scientists point out that the ruling oligarchy always used governments to fool people into believing they had power, when in reality they had owners and debt. With the arrival of the singularity in the next few years, this is no longer a tenable position. So, the oligarchy is appealing to direct power politics, to quote PNAC.

http://www.antiwar.com/orig/stockbauer1.html

So, look for corporations to dominate going forward, until the erosion of government has proceeded so far, that power politics itself begins to erode and we see corporate owners power erode as well. This is not the socialist or communist prediction of the rise of the proletariat. Government at that time will have long been discredited. It will be the rise of an emergent system that depends heavily on AI and the internet, and will be beyond the control of anyone or any group.

Tomorrow, post singularity, we will have advanced AI and utility fog. This will allow individuals to wish to do a thing, and if that thing is physically possible, and they have access, the utility fog will make it so. Access and how to get it will shape post singularity society every bit as much as money and how to get it shapes our society today.

In a rational society the transition would be a smooth one. Humans are rarely rational.

Vector Currency

https://www.youtube.com/watch?v=DOkCXiqnEDA

Utility Fog

https://www.youtube.com/watch?v=Q1CKRltKS7g
http://www.nanotech-now.com/utility-fog.htm

Moon bases as resupply for interplanetary travel

So, to recap, for moon bases to work, we need;

(1) Water on the moon we're going to use,
(2) An abundant low cost power source,
(3) The means to turn that resource into rocket fuel,

Of course, the argument has always been, if we have a lightweight portable nuclear fission power plant, or a solar pumped laser, or a fusion power plant, why not make a fission, laser, fusion rocket and dispense with chemical rockets altogether?

Well that's a good argument, however, we can imagine details - such as fission power is too dangerous, or solar power to bulky, and so forth - that says we need to have them at stationary bases making chemical fuels for chemical rockets.

Since actual decisions must await actual programmes that actually do something, one can argue interminably about what's better. Yet, to understand a thing its good to think it through, and give it real consideration.

So, let's do that now.

Deimos Water Company
http://www.spacefuture.com/archive/t..._company.shtml

According to this study, If you look at the energetics involved, Deimos - the outermost moon of Mars - is the best place to mine water to support an interplanetary transport system. The link above goes into detail and worth looking at since the details will also work with a water supply on the moon with some slight variation.

The discovery of water at the moon's poles also make it an interesting possibility.

http://www.space.com/27388-nasa-moon...ons-water.html

Practical Program that may be started today;

Now, the development of low cost solar panels, along with low cost MEMS based ion rockets that can use water efficiently as propellant, and efficient laser beaming of power, shape the sort of system that is suitable.

(1) Low-cost, highly reusable, chemical booster on Earth;
(2) Low-cost highly reusable laser ion booster is developed;
(3) Solar power satellite that beams power to where its needed, is developed;
(4) Launch three solar power satellites into GEO separated by 120 degrees of longitude;
(5) Launch five more solar power satellites into the Earth/Moon Lagrange Points;
(6) Launch five more solar power satellites into Sol/Earth Lagrange points
(7) Establish a space station in LEO to transfer people and materiel between Earth and Moon
(8) Use space station components and beamed power ion stage to create carrier craft
(9) Use beamed power ion stage to create freighter craft
(10) Develop deep space chemical powered lander
(11) Send a fleet of spacecraft forth first to the moon, then to Deimos, then to Mars
(12) Establish a reusable link to fly regularly throughout the Earth/Moon/Mars system

Mars has a source of carbon, which is the carbon dioxide in its atmosphere. So methane is a possible propellant there. The moon, and Deimos may not have such an easily tapped source. So, we may have to use hydrogen as a fuel in that case. In any even, multi-mode tankage, and multi-mode engines, are preferred over highly specialised single use types. At least ones that can be easily retuned.

Methane Rockets

http://www.dlr.de/Portaldata/55/Reso...5-0212prop.pdf

Methane Propellant

LNG: 422.5 kg/m3 density
112 K - BP
91 K - MP
309.6 seconds - Isp (with LOX, Sea Level)
368.9 seconds - Isp (with LOX, Vacuum)
3.21 - O/F Ratio
830 kg/m3 - bulk density with LOX

Hydrogen Propellant

LH2: 71.0 kg/m3 density
20 K - BP
14 K - MP
391.0 seconds - Isp (with LOX, Sea Level)
451.0 seconds - Isp (with LOX, Vacuum)
6.00 - O/F Ratio
280 kg/m3 - bulk density with LOX

Oxidiser

LOX: 1,140.0 kg/m3 density
90 K - BP
54 K - MP

The point of this is that for a given weight of oxygen, you need 1.86x as much LNG by weight, and 3.18x the volume of hydrogen as LNG.

Weight and Volume Comparison

kg density volume ratios

LOX/LH2
1000 71 14.1 2.676 - LH2
6000 1140 5.3 1.000 - LOX

LOX/LNG
1869 422.5 4.4 0.841 - LNG
6000 1140 5.3 1.000 - LOX

Common Core Interplanetary Module;

So, what pops out from this analysis is that we could have a common deep space module that is configured as a zero boil off tank for LH2, LNG, or LOX, and making use of the 'wet lab' concepts from the 1950s through 70s, from which Skylab was built, we make our tanks big enough to live in is the minimum. Making them spherical, with connections built between using a variant of the common berthing mechanism on the ISS.

Consider then;

A sphere 5.24 meters (17.2 ft) in diameter, holds 86 tonnes of LOX, 5.36 tonnes of LH2, or 31.9 tonnes of LNG. It also has the same interior volume as the Harmony ISS module. 75.5 cubic meters.

Sphere packing
http://math.mit.edu/classes/18.095/2...lect_notes.pdf

Now, if we have 2 LH2 modules and 1 LOX module, we will only be able to use 74.7% of the LOX on board, which is actually okay, if you plan to breathe oxygen and can make use of it that way. You put in only what you need. As a habitation module, a 17.3 ft diameter floor, occupied on both sides, give a total of 464 square feet (43 sq m) living space, and life support and other hardware is attached through the berthing mechanism.

If we have 1 LOX modules for each 2 LNG modules we make use of 59.4% of the LOX for propellant, leaving spare oxygen if needed for breathing. Alternatively, we only fill the LNG tank up 84% capacity, or take extra if we have use for LNG at our destination.

Hydrogen and Oxygen can be used to produce chemical power on demand, using a fuel cell, if needed. Natural gas and Oxygen can be used likewise, with an appropriately configured fuel cell.

https://www.youtube.com/watch?v=xK3yxn69q8U

With MEMS based propulsive skin built into the exterior of each zero boil off tank the units are easily moved and can be configured into a wide range of uses.

The same module holds

86.00 tonnes of LOX,
5.36 tonnes of LH2, or
31.9 tonnes of LNG.

A subscale oxygen tank - 3.8 meters in diameter - holds 32.2 tons of LOX - is perfectly suited for the larger LH2 tank - provides an extra capacity of LOX for LNG operations - and a smaller habitable module, and smaller systems generally.

31.9 tonnes of LNG require 102.4 LOX - 16.4 more tonnes than is contained in the larger module. So, many configurations are possible with one or two systems such as these.

The spheres are built around dodecahedral frames and you may also put the smaller sphere inside the larger, which also has great utility.

28.2 tonnes of water based electrospray ion propellant may be stored in the smaller sphere. Electrospray ion engines with 15 km/sec exhaust speeds built into the propulsive skin of the spacecraft, allow a combined module to receive energy and communications via laser or maser beam from solar power stations, and carry people on board. Waste water properly processed may also be used as propellant for such engines.

Using LOX/LH2 on the moon, we have 4.4 km/sec exhaust speeds to carry out 3..2 km/sec delta vee from the lunar surface and back.

With an 11% structure fraction, this means we must expend 1384.6 kg of LH/LOX propellant for every 1,000 kg of payload.

On Deimos, there is no gravity well to speak of, and with the atmosphere on Mars, you can aerobrake, so things are must easier there.

However, there is another possibility. Namely, the ability to use an electromagnetic cannon to shoot material from the lunar surface into orbit.

https://ntrs.nasa.gov/archive/nasa/c...0110007073.pdf

So, the rocket based delivery system is used for people and other fragile cargo that cannot be transported easily by launcher.

So what would a mission look like once all the parts and pieces were in place?

You launch on a highly reusable multi-stage rocket into LEO from Earth. You wait at the space station for the arrival of a beam powered ion engine deep space ship. You transfer to that ship when it arrives. It flies to the moon and enters moon orbit. It is joined by a rocket supply ship, which you can take to the lunar surface, and propellant supply drones launched by electromagnetic launcher.

As you while away your time on the lunar colony, your interplanetary ship is joined by others. When the planets are aligned, its time to leave, you blast back to lunar orbit, and depart aboard your beam powered ion rocket craft.

Arriving at Mars you receive power from the Mars solar stations, and slow into Mars orbit, landing, though docking might be a better phrase, at Deimos.. There you take a local shuttle down to the Martian surface. Using chemical rockets to transfer to a re-entry altitude above Mars, and aerobrake to slow to a soft landing, which is accomplished again by chemical rockets. Chemical rockets boost you out of Mars' atmosphere. Though even here, due to the low density of the carbon dioxide atmosphere, electromagnetic launchers are used on Mars for resupply. Particularly at higher altitudes.

http://newmars.com/forums/viewtopic.php?id=2609

Still there is sufficient oxygen and nitrogen on Mars to pressurise domes made of plastic from materials extracted from water and carbon dioxide -to create Earth normal atmospheric conditions inside.

https://www.linkedin.com/pulse/20141...of-air-on-mars

On Mars people can return to the Moon and then to Earth. People can also choose to rove deeper into the solar system, to the asteroids and beyond. The asteroids have considerable water in them. Ceres has more fresh water than Earth! Self replicating machine systems will rebuild them into thousands of open air space colonies.

https://www.linkedin.com/pulse/how-f...o-william-mook

This is before we build photonic thrusters that accelerate us to near light speed using a large fraction of the sun's output.

https://vimeo.com/40197828
https://www.linkedin.com/pulse/20140...e-in-our-reach
https://www.linkedin.com/pulse/indus...s-william-mook

  #3  
Old May 30th 17, 11:59 AM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,524
Default Mining the moon for rocket fuel to get us to Mars

In article ,
says...
Don't get me wrong, I think *eventually* we'll be mining the moon for
water to turn into LOX and LH2 (or possibly methane) to supply a fuel
depot in lunar orbit. But, needless to say, I think the supporters of
this notion are daft if they think it's going to happen in the next 20
years or so by building a freaking factory on the moon that's capable of
building mining equipment that's not JPL class "toys" that wear out
faster than you can build them.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.


Development is non-linear and results in a technological singularity.
Growth is not

y = EXP(t), t=0 to infinity

it is

y = 1/(t-1), t = 0 to 1

Where one is the year 2035AD and 0 is now.

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

The singularity is generally thought of as a time when machines are
smarter than people, and this is true, however, it involves more
than that. Anything it is physically possible to do, will be doable
after this date.


Yes, this b.s.: "hypothesis that the invention of artificial
superintelligence will abruptly trigger runaway technological growth,
resulting in unfathomable changes to human civilization".

This is a theory and it's not generally accepted because you can't prove
that it will happen, until it happens. For example, Steven Pinker
stated in 2008:

There is not the slightest reason to believe in a coming singularity.
The fact that you can visualize a future in your imagination is not
evidence that it is likely or even possible. Look at domed cities,
jet-pack commuting, underwater cities, mile-high buildings, and
nuclear-powered automobiles?all staples of futuristic fantasies when
I was a child that have never arrived. Sheer processing power is not
a pixie dust that magically solves all your problems. (...)

That and we're decades away from "real" artificial intelligence.
Anything approaching that today has as its input many man-years of
software development done by people like me. Hell, we're years away
from making all software products multi-threaded yet desktop machines
today rarely have less than 4 physical cores (8 with hyper-threading).

Software is falling well behind the hardware, because the hardware is
hitting a roadblock in terms of processing speed. Hardware is moving
towards multiple cores capable of parallel processing, yet there is
precious little software written from the ground up that actually takes
advantage of that.

So called artificial intelligence is the latest in a long string of
"silver bullet" solutions that sounds great, on paper, yet in practice
has yet to be demonstrated in a meaningful way. We're a long, long way
from true artificial intelligence that can learn on its own. What we
have now are man years of (unacknowledged) human effort leading up to
tiny demonstrations of "machine learning" that are extremely constrained
to the task at hand. In other words, demos and vaporware.

The Delta launcher took 30 years and $60 billion to develop. SpaceX
took 15 years and $10 billion. RocketLab took 4 years and $100
million and its present capacity is the capacity of the original
Delta space launcher was less than the Electron (RocketLab's
launcher). The trend toward more capacity at less cost is obvious.


You're distorting the facts greatly. Which Delta are you talking about?
As for Falcon 9, its development cost was a hell of a lot less than $10
billion. And Rocket Lab has yet to demonstrate it can get to orbit, so
they're quite simply not done expending development money. This is all
money paid to people (engineers, machinists, and the like) not to
artificial intelligences.

The singularity approacheth.


Bull****. The above paragraph written by you is you distorting the
facts to fit your world view, which is not a given. It's greatly in
dispute.

The discovery of water ice on the poles of Mercury, have awakened
many to the possibility that water is a lot more common on rocky
planets than previously thought. It seems protons in the solar
wind, interact with silicates in the rocky planet to create water
and if a rocky planet or moon can hang on to it, that can be
accumulated, and used as a propellant resource.


Yes, possibilities. But mining and refining water on Mercury, or any
other planetary body in the solar system, hasn't even been demonstrated
yet. Making methane on Mars from hydrogen brought from earth and CO2
from the atmosphere looks to be about the simplest case possible, and we
haven't even done that yet.

The use of Earth's moon and moons in general as resource bases is
energetically very favourable.


This is where I call bull****. The delta-V looks favorable, but I do
not believe for a single minute that the aerospace engineers have a
freaking clue how hard it will be to mine lunar ice and then process the
rocks and muck into pure H2 and O2 to use as "rocket fuel".

Again, I watched a documentary not long ago talking about the next JPL
built Mars rover and the engineer they interviewed was testing new
ALUMINUM wheel designs for the rover, because the light weight was the
most important metric, of course. You simply cannot build mining
equipment worth a damn with that approach.

Not only around Earth, but around Mars. Deimos and Phobos are
thought to have lots of water in them as well. Since they have
very low densities.


Again, we have not demonstrated mining of off planet rocks to make H2
and O2. The engineers have no idea how hard that will be because
they're freaking aerospace engineers. I have that degree and I know how
blinded they are to the realities they'll face.

So, finding water is the first step.


And it's not worth a damn if you can't mine and process it in mass
quantities. We're a long damn way away from that.

An abundance of power is the second step.


Yeah, and the engineers have a decent handle on that part of the
problem. We know how to scale existing systems that work.

Advanced tooling is the third step.


And here again is another area where the aerospace engineers pushing
this vision are being overly optimistic. 3D printers only work on earth
because the feed stock provided to them is extremely pure and uniform
(whether that's metal powder in a mix to form a specific alloy or
whether that's a spool of plastic with very specific properties).
Getting that quality of feed stock from local materials will be
extremely challenging and cannot be hand-waved away.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #4  
Old May 31st 17, 05:09 AM posted to sci.space.policy
David Spain
external usenet poster
 
Posts: 2,484
Default Mining the moon for rocket fuel to get us to Mars

On 5/28/2017 10:21 AM, Jeff Findley wrote:
First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF?


There is quite a lot of "exercise for the student" type problems here.
There is a lot of work & study needed about lunar industrialization for
sure including mining.

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up
that has limited capacity for manufacture of the "heavy gear". Heavy
feed stock ( steel, etc) would then be sent
up subsequently for lunar manufacture. Enabling a heavy mfg. capability
via bootstrapping. At this point my conjecture
is pretty much a total hand wave, but I could at least see it as a
possibility. Would need some math to determine if
this would be preferable to just shipping up the heavy equipment
directly. I suppose if the scale is massive enough
the bootstrap approach might be the only really feasible one. Further
study needed....

But no, we'll do it all with SLS. Why waste money on studies?

Dave

  #5  
Old May 31st 17, 07:08 AM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Mining the moon for rocket fuel to get us to Mars

On Wednesday, May 31, 2017 at 4:09:40 PM UTC+12, David Spain wrote:
On 5/28/2017 10:21 AM, Jeff Findley wrote:
First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF?


There is quite a lot of "exercise for the student" type problems here.
There is a lot of work & study needed about lunar industrialization for
sure including mining.

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up
that has limited capacity for manufacture of the "heavy gear". Heavy
feed stock ( steel, etc) would then be sent
up subsequently for lunar manufacture. Enabling a heavy mfg. capability
via bootstrapping. At this point my conjecture
is pretty much a total hand wave, but I could at least see it as a
possibility. Would need some math to determine if
this would be preferable to just shipping up the heavy equipment
directly. I suppose if the scale is massive enough
the bootstrap approach might be the only really feasible one. Further
study needed....

But no, we'll do it all with SLS. Why waste money on studies?

Dave


Composite Tank Studies

http://www.compositesworld.com/artic...-scores-firsts

Aerospike Engine Studies

https://www.youtube.com/watch?v=-0Y0FS8Z1Qk

If the studies are a pre-amble to doing a thing! They're essential to develop efficient tooling and procedures.

Electron facts:
• Lift off mass: 12,550kg
• Propellant mass: 11,300kg
• Propellants: Liquid oxygen and kerosene
• Length: 17m
• Diameter: 1.2m
• Top speed: 27,500kph
• First stage engines thrust (s.l./vac) : 153.5 / 184.6 kN (9 engines)
• Second stage engine thrust (vac) : 22.2 kN
• Nominal orbit: 500km circular sun synchronous
• Isp 353 sec
• Ve 3.46 km/sec.

12,396.69 kg Take Off Weight

9,959.04 kg propellant - First Stage
7,161,56 kg LOX
2,787.48 kg Kerosene

1,074.01 kg - Stage 1 Structure Weight

1,363.63 kg Total Stage 2 Weight

1,095.49 kg Propellant Weight
787.77 kg - LOX
307.72 kg - Kerosene

118.14 kg - Stage 2 Structure

150.00 kg - Payload

Using two First Stage Boosters as Liquid Strap-On Boosters, increases payload to 645 kg to the same orbits as the single unit.

Using four First Stage Boosters as Liquid Strap-On Boosters, increases payload to 1,625 kg to the same orbits as the previous launchers.

* * *

Increasing from 1.2 m diameter system to a 5.5 m diameter system and from 17 m length to 77.92 m length, increases launch weight from 12,400 kg to 1,194,000 kg and payload weight from 150 kg to 14,440 kg.

1,193,576.39 kg Take Off Weight
958,874.91 kg Propellant Weight
689,528.02 kg - LOX
269,346.88 kg - Kerosene
103,408.08 kg - Structure Stage 1

131,292.40 kg - Stage Two Total Weight
105,476.24 kg - Propellant Weight
75,848.08 kg - LOX
29,628.16 kg - Kerosene
11,375.89 kg - Structure Stage 2

14,442.27 kg - Payload

A three element common core booster of this size using these propellants lifts 62,100 kg into LEO.

A seven element common core booster of this size using these propellants lifts 156,450 kg into LEO.

A cost of $2,000 per kg for structure translates to $2.4 million for each of the smaller vehicles. Another $1.1 million to run each campaign, $3.5 million total out of pocket costs. Insurance and other costs add to this.

The larger vehicle costs $187 million to build, and $3.0 million to run each campaign.

* * *

Reusable systems, similar to SpaceX approach, using inflatable wings and tow planes, rather than floating launch platforms, to bring parts and pieces back to the launch center, and allowing them to land vertically like the tail sitter aircraft of the 1950s.

Highly reusable with 1,900 uses per airframe, a CAPEX of $100,000 per flight for the larger vehicle, $1,260 per flight for the smaller vehicle. Fast turn around with 100 flights per year, a 19 year life span for the vehicle. Total costs run $1.5 million for 150 kg - $10,000/kg and $3.1 million for 14,400 kg - $215/kg

The larger clustered vehicles are $3.3 million and $3.7 million respectively. This reduces cost to $53/kg and $24/kg respectively.

For the smaller clusterd vehicles prices are $2,500 per kg and 1,120 per kg respectively.

156.45 tonnes at 22 MW per tonne launches a power satellite capable of producing 3.44 GW continuously on orbit.

  #6  
Old May 31st 17, 09:47 AM posted to sci.space.policy
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,545
Default Mining the moon for rocket fuel to get us to Mars

William Mook wrote:

On Wednesday, May 31, 2017 at 4:09:40 PM UTC+12, David Spain wrote:
On 5/28/2017 10:21 AM, Jeff Findley wrote:
First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF?


There is quite a lot of "exercise for the student" type problems here.
There is a lot of work & study needed about lunar industrialization for
sure including mining.

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up
that has limited capacity for manufacture of the "heavy gear". Heavy
feed stock ( steel, etc) would then be sent
up subsequently for lunar manufacture. Enabling a heavy mfg. capability
via bootstrapping. At this point my conjecture
is pretty much a total hand wave, but I could at least see it as a
possibility. Would need some math to determine if
this would be preferable to just shipping up the heavy equipment
directly. I suppose if the scale is massive enough
the bootstrap approach might be the only really feasible one. Further
study needed....

But no, we'll do it all with SLS. Why waste money on studies?


Composite Tank Studies


Another thread MookJacked...

snip MookSpew


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine
  #7  
Old May 31st 17, 11:57 AM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,524
Default Mining the moon for rocket fuel to get us to Mars

In article , says...
There is quite a lot of "exercise for the student" type problems here.
There is a lot of work & study needed about lunar industrialization for
sure including mining.

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up
that has limited capacity for manufacture of the "heavy gear". Heavy
feed stock ( steel, etc) would then be sent
up subsequently for lunar manufacture. Enabling a heavy mfg. capability
via bootstrapping. At this point my conjecture
is pretty much a total hand wave, but I could at least see it as a
possibility. Would need some math to determine if
this would be preferable to just shipping up the heavy equipment
directly. I suppose if the scale is massive enough
the bootstrap approach might be the only really feasible one. Further
study needed....


I think the "further study needed" is the key here. Researchers don't
really know how they'd do this, so they're fishing for funding. Don't
get me wrong, this is certainly worth doing some work on, but this is
not a next 10 or 20 year solution. It's more like a next 25 to 100 year
solution.

But no, we'll do it all with SLS. Why waste money on studies?


Flags and footprints. We couldn't possibly do anything differently than
Apollo now could we? :-(

The reality is there is so much between the SLS approach and the "living
completely off the land" approach. I don't see "living off the land"
becoming viable until you can start launching heavier bits like machine
tools without resorting to making them out of aluminum, titanium, and
unobtainium. Shaving every last gram off of payloads due to high launch
costs is freaking expensive! It results in one-off payloads that might
work, or they might not.

To build a colony, we need to get to the point where we're buying
machine tools "off the shelf" and simply shipping them to the moon and
Mars. Run them in pressurized environments so astronauts can service
them in "shirt sleeves". By then, astronauts will be selected for their
skill at fixing machine tools, not for their ability to fly a fighter
jet in combat or because they have the most college degrees.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #8  
Old May 31st 17, 10:24 PM posted to sci.space.policy
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,545
Default Mining the moon for rocket fuel to get us to Mars

JF Mezei wrote:

On 2017-05-31 00:09, David Spain wrote:

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up


There is a problem with that. It is quite possible that the hardware
needed to produce the steel and then build the mining truck is heavier
than the mining truck. So you might has well ship the truck.


That's not a 'problem' unless you only ever need the one truck.


When you look at North America, France initially shipped all goods to
its new territory (and saw it as export market for its own businesses).


France wasn't interested in colonization.


It wasn't until the colony was large enough that it started to build its
own stuff and ceased to be dependant on France. (big difference is that
there was plenty of raw materials like wood here).


So you think France was shipping prefab houses?


The only material available in large quantities easily in Mars is sand.


That's rather like saying that the only material available in large
quantities on Earth is dirt.


So it is far more likely that the first stuff produced on Mars will be
something like concrete and structures more likely to look like homes on
Tatooine than some pre-fab Fibreglass shiny structures.


Well, since EVER building the latter would be sort of insane given the
surface radiation environment, yeah, structures are unlikely to look
like that EVER.


Linings (to make walls airtight) and windows would have to come from
earth for a very long time before they can be manufactured locally.


What the hell do you need either of those things for? You think given
'Marscrete' and power that achieving something airtight is difficult?


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
  #9  
Old June 1st 17, 01:10 AM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Mining the moon for rocket fuel to get us to Mars

On Tuesday, May 30, 2017 at 10:59:10 PM UTC+12, Jeff Findley wrote:
In article ,
says...
Don't get me wrong, I think *eventually* we'll be mining the moon for
water to turn into LOX and LH2 (or possibly methane) to supply a fuel
depot in lunar orbit. But, needless to say, I think the supporters of
this notion are daft if they think it's going to happen in the next 20
years or so by building a freaking factory on the moon that's capable of
building mining equipment that's not JPL class "toys" that wear out
faster than you can build them.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.


Development is non-linear and results in a technological singularity.
Growth is not

y = EXP(t), t=0 to infinity

it is

y = 1/(t-1), t = 0 to 1

Where one is the year 2035AD and 0 is now.

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

The singularity is generally thought of as a time when machines are
smarter than people, and this is true, however, it involves more
than that. Anything it is physically possible to do, will be doable
after this date.


Yes, this b.s.: "hypothesis that the invention of artificial
superintelligence will abruptly trigger runaway technological growth,
resulting in unfathomable changes to human civilization".

This is a theory and it's not generally accepted because you can't prove
that it will happen, until it happens. For example, Steven Pinker
stated in 2008:

There is not the slightest reason to believe in a coming singularity.
The fact that you can visualize a future in your imagination is not
evidence that it is likely or even possible. Look at domed cities,
jet-pack commuting, underwater cities, mile-high buildings, and
nuclear-powered automobiles?all staples of futuristic fantasies when
I was a child that have never arrived. Sheer processing power is not
a pixie dust that magically solves all your problems. (...)

That and we're decades away from "real" artificial intelligence.
Anything approaching that today has as its input many man-years of
software development done by people like me. Hell, we're years away
from making all software products multi-threaded yet desktop machines


today rarely have less than 4 physical cores (8 with hyper-threading).


AI is a solved problem. You don't get that.

https://www.youtube.com/watch?v=7Pq-S557XQU

Steven Pinker does! That's because Steven in 2016 says something substantially different than he did ten years ago!

He knows he lost the argument over machines ever being able to think, so he had refined his argument to the area he knows best, human psychology.

In 2016 Steven isn't arguing that machines cannot think any longer. Rather, he is arguing that when they do think, we will put safeguards in the software to protect us.

http://bigthink.com/videos/steven-pi...nce-apocalypse

This is distinctly different than his position 10 years earlier! He makes some good point though, which are well founded in human psychology;

(1) there is a tendency for alpha males to fear AI, and that is at root irrational as racism is,
(2) there is a tendency to rely on AI to solve our all problems post singularity, this is irrational is religion is,

I tend to think these impulses are likely to shape the post-singularity political and religious landscape. Of course at that time, Pinker will be the 'grand old man' and his arguments will morph into important insights into the human condition at that time!

I'm reminded of John Manyard Keynes, the famous economist, statement, "When the facts change, I change my mind. What do you do, sir?" That's what all intelligent people do, and that's what Pinker had done.

haha..


Software is falling well behind the hardware, because the hardware is
hitting a roadblock in terms of processing speed. Hardware is moving
towards multiple cores capable of parallel processing, yet there is
precious little software written from the ground up that actually takes
advantage of that.


That is changing too. What you are saying may have been current and accurate 24 months ago - but not so today.

https://qz.com/985808/your-it-job-is...-for-a-living/

The proper reading of the situation 24 months ago is that the difficulty of software development, maintenance, and support, have pressured the industry to AUTOMATE IT. Which has borne fruit!

Here's a proper analysis of the same situation in the same timeframe

https://insidehpc.com/2015/06/why-ha...ftware-behind/

And IBM four years ago predicted its AI will be used to write software for this very reason

https://www.wired.com/insights/2013/...e-development/

So, as per usual, you've got it bass ackwards.


So called artificial intelligence is the latest in a long string of
"silver bullet" solutions that sounds great, on paper, yet in practice
has yet to be demonstrated in a meaningful way.


Liar!

We're a long, long way
from true artificial intelligence that can learn on its own.


Nortorious provaricator!

What we
have now are man years of (unacknowledged) human effort leading up to
tiny demonstrations of "machine learning" that are extremely constrained
to the task at hand. In other words, demos and vaporware.


Perjurer!

The Delta launcher took 30 years and $60 billion to develop. SpaceX
took 15 years and $10 billion. RocketLab took 4 years and $100
million and its present capacity is the capacity of the original
Delta space launcher was less than the Electron (RocketLab's
launcher). The trend toward more capacity at less cost is obvious.


You're distorting the facts greatly.


No I'm not. You are.

Which Delta are you talking about?


yawn You have to ask?

As for Falcon 9, its development cost was a hell of a lot less than $10
billion.


SpaceX has spent $10 billion since its inception, and the Falcon 9 could not have been built without everything that came before it. You don't get that.

https://qz.com/281619/what-it-took-f...space-company/


And Rocket Lab has yet to demonstrate it can get to orbit, so
they're quite simply not done expending development money. This is all
money paid to people (engineers, machinists, and the like) not to
artificial intelligences.

The singularity approacheth.


Bull****.


You haven't a clue and are spouting nonsense.

https://www.youtube.com/watch?v=1uIzS1uCOcE

The above paragraph written by you is you distorting the
facts


No, you're the liar here.

to fit your world view,


Liar.

which is not a given. It's greatly in
dispute.


Nope.

The discovery of water ice on the poles of Mercury, have awakened
many to the possibility that water is a lot more common on rocky
planets than previously thought. It seems protons in the solar
wind, interact with silicates in the rocky planet to create water
and if a rocky planet or moon can hang on to it, that can be
accumulated, and used as a propellant resource.


Yes, possibilities.


Good of you to admit that.

But mining and refining water on Mercury, or any
other planetary body in the solar system, hasn't even been demonstrated
yet.


My friend Robert Zubrin, whom I've collaborated with, and whom I've met at the White House during the Bush administration, has demonstrated processes that do just that.

Making methane on Mars from hydrogen brought from earth and CO2
from the atmosphere looks to be about the simplest case possible, and we
haven't even done that yet.


You read 15 year old books and think its current state of the art. lol.

Making methane from carbon dioxide and water had been demonstrated.

https://ntrs.nasa.gov/archive/nasa/c...0120016419.pdf

Solar or nuclear energy is used to break down water into hydrogen and oxygen

4 H2O + energy -- 4 H2 + 2 O2 (1)

Hydrogen is then used to react with CO2

4 H2 + CO2 -- CH4 + 2 H2O (2)

Process water is combined with fresh water ice to supply 4 H2O at step (1)

In this way

NET REACTION:

2 H2O + CO2 -- CH4 + 2 O2 (3)

MASS BALANCE

2*18 + 44 = 16 + 2*32 amu
36 44 16 64 amu
1 litre 1.22 kg = 0.44 kg + 1.78 kg

Using 15.74 MJ of energy one litre of water is converted into 440 grams of methane and 1.78 kg of oxygen.

In practical systems, 22.5 MJ are used for each litre of water processed.

The use of Earth's moon and moons in general as resource bases is
energetically very favourable.


This is where I call bull****.


HAHA - you imagine what you say means something? Only if it comports to reality.

The delta-V looks favorable,


Delta V requires energy!

but I do
not believe for a single minute that the aerospace engineers have a
freaking clue how hard it will be to mine lunar ice and then process the
rocks and muck into pure H2 and O2 to use as "rocket fuel".


Your belief is wrong.

Again, I watched a documentary not long ago talking about the next JPL
built Mars rover and the engineer they interviewed was testing new
ALUMINUM wheel designs for the rover, because the light weight was the
most important metric, of course. You simply cannot build mining
equipment worth a damn with that approach.


Liar

http://www.zdnet.com/article/deep-sp...teroid-mining/

https://www.crcpress.com/Microroboti.../9781420061956


Not only around Earth, but around Mars. Deimos and Phobos are
thought to have lots of water in them as well. Since they have
very low densities.


Again, we have not demonstrated mining of off planet rocks to make H2
and O2.


Liar - Pioneer Astronautics and a host of NASA contractors have demonstrated precisely how to process water and carbon dioxide into methane and LOX.

The engineers have no idea how hard that will be because
they're freaking aerospace engineers.


You live in a bizarro world that is opposite to the real world! Aerospace engineers now precisely how hard that will be because they're aerospace engineers.

I have that degree and I know how
blinded they are to the realities they'll face.


You should have your degree taken away then. You're a freaking liar and an idiot besides.

So, finding water is the first step.


And it's not worth a damn if you can't mine and process it in mass
quantities. We're a long damn way away from that.


Liar.


An abundance of power is the second step.


Yeah, and the engineers have a decent handle on that part of the
problem. We know how to scale existing systems that work.


I'm glad you agree. You are correct.

Advanced tooling is the third step.


And here again is another area where the aerospace engineers pushing
this vision are being overly optimistic.


Liar

3D printers only work on earth
because the feed stock provided to them is extremely pure and uniform
(whether that's metal powder in a mix to form a specific alloy or
whether that's a spool of plastic with very specific properties).
Getting that quality of feed stock from local materials will be
extremely challenging and cannot be hand-waved away.


Liar

http://www.popsci.com/feed-your-3-d-...cycled-plastic

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.


All opinions posted by Jeff are apparently lies derived from deep seated ignorance of reality and motivated by general hatred of humanity, particularly those humans better schooled, better educated, and generally smarter than he.

  #10  
Old June 1st 17, 01:14 AM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Mining the moon for rocket fuel to get us to Mars

Nonsense

On Wednesday, May 31, 2017 at 8:47:24 PM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Wednesday, May 31, 2017 at 4:09:40 PM UTC+12, David Spain wrote:
On 5/28/2017 10:21 AM, Jeff Findley wrote:
First, this isn't my "subject", it's the title of this article:

Mining the moon for rocket fuel to get us to Mars
May 14, 2017 8.04pm EDT ?Updated May 18, 2017 9.01am EDT
http://theconversation.com/mining-th...-to-get-us-to-
mars-76123

I saw this article (or a variation of it from another online
publication) on Twitter. I replied something to the effect that this
article glosses over all of the hard stuff, like the fact that the lunar
soil and rock is horribly abrasive and that mining equipment isn't
anything like the lightweight rovers that NASA/JPL has flown in the
past. For crying out loud, JPL keeps using ALUMINUM for the rover
wheels to keep them light, even though they're wearing holes in the
things after less than 100 miles. Mining equipment can't be that weak!
Anyway, I replied that mining equipment is *really heavy* because it's
made of steel and hardened steel.

The response by one Twitter follower was along the lines of, "That's why
the mining equipment will be built on the moon from local materials".


At that point, "I couldn't even". I mean WTF?

There is quite a lot of "exercise for the student" type problems here.
There is a lot of work & study needed about lunar industrialization for
sure including mining.

One factor that may get some consideration down the road is the idea of
what I'd call incremental industrial "densification". The idea being
that lightweight gear is first sent up
that has limited capacity for manufacture of the "heavy gear". Heavy
feed stock ( steel, etc) would then be sent
up subsequently for lunar manufacture. Enabling a heavy mfg. capability
via bootstrapping. At this point my conjecture
is pretty much a total hand wave, but I could at least see it as a
possibility. Would need some math to determine if
this would be preferable to just shipping up the heavy equipment
directly. I suppose if the scale is massive enough
the bootstrap approach might be the only really feasible one. Further
study needed....

But no, we'll do it all with SLS. Why waste money on studies?


Composite Tank Studies


Another thread MookJacked...

snip MookSpew


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine


 




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