Author Topic: Impact of lunar free water on Exploration Architecture  (Read 31748 times)

Offline Robotbeat

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Re: Impact of lunar free water on Exploration Architecture
« Reply #20 on: 05/23/2016 05:03 AM »
Delta-v is not economics.
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Offline nadreck

Delta-v is not economics.

No but it is one of the inputs, I am pointing out that delivering the propellant to LEO only costs 2.8km/s of propulsive ΔV.  Now since the transports to EM-L2 from the lunar surface and LEO from EM-L2 need to return, it costs more than just the mass ratio implied by 2.8km/s, but definitely a lot less than the mass ratio needed for the full 11km/s round trip ΔV from lunar surface to LEO and back. So as I pointed out the economics are dictated by the ratio of water produced and propellant refined on the lunar surface to the amount supplied in LEO.
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline Robotbeat

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Re: Impact of lunar free water on Exploration Architecture
« Reply #22 on: 05/23/2016 06:26 AM »
You need a reusable rocket to do lunar propellant at any kind of sensible value. You will likely have to have this on Earth as well. What's easier, a rocket base on the Moon or on Earth?
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Offline Robotbeat

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Re: Impact of lunar free water on Exploration Architecture
« Reply #23 on: 05/23/2016 06:33 AM »
We have very few data points for cost of a lunar rocket. The Apollo lunar lander was incredibly expensive, perhaps about as much as a Saturn V, even though the Saturn V had FAR more payload and delta-v. I don't think delta-v is a very good metric for cost. If you held everything else equal, sure, higher delta-v means less payload and higher cost, but everything is MOST CERTAINLY NOT equal!

Heck, on the Earth, the oxidizer is (chemically) free in the air and the fuel is (chemically) free in the ground.
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Offline Steven Pietrobon

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Re: Impact of lunar free water on Exploration Architecture
« Reply #24 on: 05/23/2016 08:06 AM »
We have very few data points for cost of a lunar rocket. The Apollo lunar lander was incredibly expensive, perhaps about as much as a Saturn V, even though the Saturn V had FAR more payload and delta-v.

In 2010 dollars, total Saturn V (including engines) cost was $42.3B. The total LM cost was $14.4B, about 34% of the cost of the Saturn V.
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Offline Warren Platts

We have very few data points for cost of a lunar rocket. The Apollo lunar lander was incredibly expensive, perhaps about as much as a Saturn V, even though the Saturn V had FAR more payload and delta-v.

In 2010 dollars, total Saturn V (including engines) cost was $42.3B. The total LM cost was $14.4B, about 34% of the cost of the Saturn V.

A better data point would be the DC-X. Other than the fact that it landed vertically, it's not unlike what an ACES-style tanker-lander would be like: merely tanks and a few RL-10 rocket engines with no other payload. It was also reusable. From beginning to end, the program lasted 21 months, and cost around $100M in today's $$$.

Meanwhile, PSRs are theorized to contain 1-10% wt water in surface layer regolith - in areas that are identifiable from a combination of orbital observations. In a region where constantly solar powered operations could be possible, because of permanently sunlit peaks - and the feasibility of utilizing any of the lunar resources depends primarily on the available energy source required for processing, anyway.

Although certainly valuable and interesting, I don't see why should this shift the primary focus away from polar volatile research .

This possibility that water can be found 20-80 km down with luck is fascinating, but I'm with savopuro... if we are trying to decide how to bootstrap up, using polar volatiles first seems like it would be less effort than drilling a long ways into the crust, especially if poor understanding will lead to dry holes. That sounds like it would be hard to do in early days.

So why not exploit polar ice first? Use the water to in part power industrialization and exploration of the moon.  Over time the moon will be well enough mapped and understood and there will be enough facilities and materiel present that doing drilling will be less risk, since if it is a dry hole, we haven't lost nearly as much time and effort (and used up as much landed mass) proportionately....

The idea that these meniscus hollows (MHs), rimless pits (RPs), irregular mare patches (IMPs), pseudo-calderas (PCs), lunar maars (LMs), whatever-you-want-to-call-them (although I have to admit that Braden's "irregular mare patches" makes for the best acronym) could be likely places to prospect for economically recoverable volatiles is not original to me (e.g., cf. the Shultz et al. 2006 paper linked to in my previous post). I'm not saying we must forget about the poles, but that we shouldn't forget about these structures either. Also, I'm not proposing that we drill 20-80 km down. Somehow--if the outgassing hypothesis is correct--volatiles were delivered right to the surface, so a very shallow well, say 10 to 100 m, might be able to yield usable quantities of volatiles.

I try to think about it from the perspective of a petroleum geologist. To make a classic oil or gas reservoir, you need  three things: (1) a source rock; (2) a reservoir rock; (3) a cap rock.

Our source rock is the purported phreatic zone located at the bottom of the fracked zone. IMO, the fact that these structures are concentrated in the lunar maria region not because the maria basalts are somehow enriched in water, but because they provide impermeable stratigraphic traps that have prevented dewatering of ancient, juvenile water deposits. Note that Wieczorek et al.'s (2012) estimates of crustal porosity did not analyze the maria regions. I am not aware of any other GRAIL analysis of the maria, but I am guessing the porosity is lower than the surrounding highlands.

The reservoir rock is the megaregolith immediately underlying the main regolith blanket. This layer should be both highly porous and permeable. In addition, these structures seem to correlate with signs of local crustal weakness; such areas could provide faults that would allow movement of volatiles from deeper traps to surface traps.

Then there is the cap rock. I'm saying that the reason these structures tend to correlate with domes at least in some places is that the regolith itself provides the cap rock. How can unconsolidated regolith form an impermeable cap rock you ask? Whilst gas molecules can diffuse through the regolith, the diffusion is a slow process. As long as the pressure is low, H2O molecules can pass through in a vapor state; but if the pressure becomes too high, the H2O will start to freeze, forming a permafrost layer. Such a layer would have two main effects: (1) it would reduce permeability to about zero; (2) it would increase the tensile strength of the regolith allowing pressure buildups greater than the regolith overburden pressure (which is on the order of 1/2 an atmosphere). But if H2O is involved, and the pressure is at 1/2 atm, and the temperature is at 1 C, then the H2O will tend to condense into a liquid form. Since the basalt flows that form the maria cause a sort of horizontal stratigraphy, there could be layers that would collect such free water and keep it from sinking back down. 

@Nadrek: thanks for pointing my arithmetic error!  :D

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Offline Robotbeat

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Re: Impact of lunar free water on Exploration Architecture
« Reply #26 on: 05/23/2016 03:53 PM »
We have very few data points for cost of a lunar rocket. The Apollo lunar lander was incredibly expensive, perhaps about as much as a Saturn V, even though the Saturn V had FAR more payload and delta-v.

In 2010 dollars, total Saturn V (including engines) cost was $42.3B. The total LM cost was $14.4B, about 34% of the cost of the Saturn V.
Or $50m (then-costs) for the lander and $110m for the rocket. Same order of magnitude. My point still stands.
« Last Edit: 05/23/2016 03:56 PM by Robotbeat »
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Offline Lar

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Re: Impact of lunar free water on Exploration Architecture
« Reply #27 on: 05/23/2016 04:20 PM »
You need a reusable rocket to do lunar propellant at any kind of sensible value. You will likely have to have this on Earth as well. What's easier, a rocket base on the Moon or on Earth?
When? Today? Or when you have a large population of loonies and robust lunar manufacturing base?

I think the history of the colonization/settlement [1] of the North American continent is instructive. Time and again, organizations did things that would have longer term payoffs, and in some cases, lost a lot of money while waiting. It may not make pure economic sense for lunar propellant on day 1, but it will eventually. The companies that do it initially may not survive, though (where is the Astor Fur Company? The Hudson's Bay Company?  the Rock Island? the Milwaukee Road? Or even the Central Pacific?). Some will survive, some merge with others, some will morph (Hudson's Bay Company, once the largest landowner in NA, and a defacto government in many areas, is a department store chain now) and some will disappear.

The idea that these meniscus hollows (MHs), rimless pits (RPs), irregular mare patches (IMPs), pseudo-calderas (PCs), lunar maars (LMs), whatever-you-want-to-call-them (although I have to admit that Braden's "irregular mare patches" makes for the best acronym) could be likely places to prospect for economically recoverable volatiles is not original to me (e.g., cf. the Shultz et al. 2006 paper linked to in my previous post). I'm not saying we must forget about the poles, but that we shouldn't forget about these structures either. Also, I'm not proposing that we drill 20-80 km down. Somehow--if the outgassing hypothesis is correct--volatiles were delivered right to the surface, so a very shallow well, say 10 to 100 m, might be able to yield usable quantities of volatiles.

Thanks for clarifying. I'm going to draw another analogy from settling the West... the Michigan Copper Rush[2].  The surface metallic copper was scooped up first because it was easy, but the ores in the region ultimately yielded fare more copper.  People made a lot of money from nugget copper before it panned out, and that money helped build infrastructure... that infrastructure made subsurface mining possible.

My argument is, go where the water is easy to get and known for sure to be there first. Once some infrastructure has grown and money is being made and the surface water is getting played out? Drill baby drill...

1 - by westerners... the indigenous people were already there
2 - c/Michigan/California/* * and c/Copper/Gold/* * as well and the same point holds.
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Offline savuporo

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Re: Impact of lunar free water on Exploration Architecture
« Reply #28 on: 05/23/2016 04:38 PM »
A better data point would be the DC-X. Other than the fact that it landed vertically, it's not unlike what an ACES-style tanker-lander would be like: merely tanks and a few RL-10 rocket engines with no other payload...
And yet again, technology testbeds, launch vehicles and spacecraft are all very different things.
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Offline Kansan52

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Re: Impact of lunar free water on Exploration Architecture
« Reply #29 on: 05/23/2016 04:58 PM »
Well, for a lay person, all this makes my head hurt but is very interesting.

Inferring from the discussion, would mining lunar ice makes thing better for BLEO? Some of the items not in the discussion, robotic equipment, strip mining for water, and mag lev launch rails.

NASA spent some Constellation money with Caterpillar for Lunar robotic equipment. So that is some of the work already done for this type of effort.

There were some papers based on resource recovery with strip mining, including H2O (if memory serves). The Caterpillars would help that type of operation.

The e-launch (mag lev launch rails) could launch containers of ice. The containers could be formed from the mined lunar materials. A recovery vehicle could rendezvous with the container for final precise delivery.

This is a very limited outline. It leaves out the most important item, a Big A$$ Budget. But a robotic operation could reduce costs by limiting or eliminating the highest cost item, people to run this.

I even saw a notion that results of the strip mining would produce gold. Since most people do not hold gold, what they own is in a depository, selling gold shares and water may make it profitable.

Offline Warren Platts

A better data point would be the DC-X. Other than the fact that it landed vertically, it's not unlike what an ACES-style tanker-lander would be like: merely tanks and a few RL-10 rocket engines with no other payload...
And yet again, technology testbeds, launch vehicles and spacecraft are all very different things.

Good point, but most of the technology required for a true spacecraft tanker-lander has already been developed by ULA. They're at the point where they're saying they don't even need to do a technology demonstration in space for their reusable, refueable Centaur/ACES. They know it will work. All that would be required for surface operations is the landing kit. Not trivial, to be sure, but not measured in 10's of billions of USD either.
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Offline savuporo

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Re: Impact of lunar free water on Exploration Architecture
« Reply #31 on: 05/23/2016 06:40 PM »
..most so the technology required for a true spacecraft tanker-lander has already been developed by ULA. They're at the point where they're saying they don't even need to do a technology demonstration in space for their reusable, refueable Centaur/ACES...
If they keep saying this for another decade with stronger conviction, as they have been for the last, I'm sure the ghost of Gerard O'Neill will grant this wish
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Offline the_other_Doug

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Re: Impact of lunar free water on Exploration Architecture
« Reply #32 on: 05/23/2016 07:15 PM »
..most so the technology required for a true spacecraft tanker-lander has already been developed by ULA. They're at the point where they're saying they don't even need to do a technology demonstration in space for their reusable, refueable Centaur/ACES...
If they keep saying this for another decade with stronger conviction, as they have been for the last, I'm sure the ghost of Gerard O'Neill will grant this wish

And I've got to say, ULA has been saying this about ACES since they announced it.  I'm really, really wary of people peddling paper spacecraft and insisting that they will be able to build them quickly, and are absolutely convinced there doesn't need to be any kind of testing program or any check-out flights.  That's not confidence -- it's arrogance.

And you know what they say, pride always cometh before the fall...   :-\
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Offline gbaikie

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Re: Impact of lunar free water on Exploration Architecture
« Reply #33 on: 05/24/2016 08:59 AM »
The best place to mine anything on the Moon is the polar regions.
One has the peaks of eternal light. Plus by connecting solar farms in different regions
one can get continuous electrical power. So with one area of peaks of eternal light one can get
80% or more of time with sunlight. Or 50% of time elsewhere on Moon has 2 weeks of darkness.

Plus one has areas where temperature is very cold, allowing low temperatures with passive cooling.
Such cooler areas are not limited to dark craters- with level ground the sun strikes at low angle. Though
a surface near vertical can warm up as much surfaces in equatorial regions.
A main problem in a vacuum in terms of any activity using energy, is getting rid of the heat- and so generally a cooler environment is more helpful rather than making it more difficult.
The lunar surface is covered with a layer of fine dust- which acts like insulation in terms of heat transfers.
Therefore a person is spacesuit in a cold crater will not get cold. Whereas things which are not generating heat, will eventually get cold. So polar regions is not like Earth's polar regions in terms of things getting colder
[or much colder] unless something isn't generating heat and/or heat can't distributed evenly.
Or a sealed can of water is not going to cold as fast as it would in Earth's cold arctic- but if given enough time eventually it will get much colder. Or in cold regions on Earth with vehicle if you turn it off and give enough time it gets to too cold to start it again. With polar region one leave the vehicle off for longer time to reach the same degree of it being cold.
But on the Moon, one can't afford parking vehicles- you want them running constantly- because of those vehicle are very expensive.
Now on the Moon one can control your immediate environment much easier than you can on Earth. One could heat with reflected light, a 10 by 10 foot area on flat ground to 1000 C and within 1 foot beyond it have it 0 C. Our atmosphere doesn't allow one to do this on Earth. Or roughly if a cold ground is somehow a problem, one warm can up- and that not as crazy as it would be on Earth.
So you do need to design things to operate within a vacuum and deal with the dust, but a "cold vacuum" doesn't add much- if any - complexity- and as I said has aspects which one take advantage of. 

The largest basic problems with mining lunar water is: lack of needed exploration, and two lack of demand of lunar water [or more water you "have to mine" the worst the problem of lack of demand becomes].
So we want to start out with a relatively low amount of water mined. Or the advantage of picking the Moon rather than asteroids, is one could start out "needing" the least amount of water mined per year.
The other main advantage of the Moon vs Space rock, is one has domestic consumption vs solely needing to export. So with Moon one starts with domestic consumption and expand the market by export. And you have a lock on the domestic consumption. Space rock require you to move the water [or whatever] to a marketplace- or it by itself doesn't have domestic marketplace. Or other people aren't going to your rock- whereas people who not doing water mining will be going to the Moon and need your water. One party can convert your water into rocket fuel, others may just want the water for another reason, such as shipped to be sold for Mars missions. You the water miner will want to buy rocket fuel at low lunar orbit [to expand and maintain your operation], you also want electrical power or chemical power for your operations. You also may want things made of iron/steel and that could made on the Moon. Etc.
« Last Edit: 05/24/2016 09:14 AM by gbaikie »

Offline Warren Platts

Heck, on the Earth, the oxidizer is (chemically) free in the air and the fuel is (chemically) free in the ground.

The same is true of the Moon. Nobody is talking about extracting water from apatite, if that's what you're implying the plan is. Indeed, there may be free H2 available at locations such as the Ina D-pseudo caldera.

Quote from: gbaike
One has the peaks of eternal light. Plus by connecting solar farms in different regions
one can get continuous electrical power. So with one area of peaks of eternal light one can get
80% or more of time with sunlight. Or 50% of time elsewhere on Moon has 2 weeks of darkness.

The only real advantage of the polar location per se (that is, other than its proximity to permanently shaded craters) is the relatively mild and constant temperature profile. The constant solar is nice, but the problem is it's coming in at 90 degrees, so you can't just lay your panels on the ground; you need to put them on masts, and then you'll have the problem of your panels shading each other. Also, most people vastly underestimate the power requirements of an industrial fuel production plant producing fuel in truly game-changing quantities. This is a long winded way of saying you'd probably want to use space-based solar power.

Drilling for volatiles trapped at  shallow levels would require VASTLY less infrastructure. A single 20 mT lander could deliver a drilling rig capable of drilling down 100 m or more.

Quote from: Doug
And I've got to say, ULA has been saying this about ACES since they announced it.  I'm really, really wary of people peddling paper spacecraft and insisting that they will be able to build them quickly, and are absolutely convinced there doesn't need to be any kind of testing program or any check-out flights.  That's not confidence -- it's arrogance.

Arrogance aside, the idea that a tanker-lander (about the simplest lunar lander imaginable) would cost in Apollo LM ballpark figures is total hyperbole.
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Offline Warren Platts

OK, I took the two databases (Stooke 2013; Braden 2014), and consolidated them into a single spreadsheet. Where there were obvious duplications, I consolidated the data into a single line. Also, although both papers use a "wraparound" method for longitude, I looked up the "selenological coordinate system in the Wikipedia. They say it's supposed to be just like Earth, and Google Earth doesn't recognize longitudes > 180, so I converted all west longitudes to the ordinary form (so that 350 = 10W = -10).

I wound up with 98 total meniscus hollows, the largest single list I know of so far (although I suspect Phil is sitting a few more! ;) ). Haven't plotted them all yet, but an obvious pattern is they are confined to maria in a latitudinal band extending from 38N to 25S.
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Offline gbaikie

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Re: Impact of lunar free water on Exploration Architecture
« Reply #36 on: 05/24/2016 07:44 PM »
Heck, on the Earth, the oxidizer is (chemically) free in the air and the fuel is (chemically) free in the ground.

The same is true of the Moon. Nobody is talking about extracting water from apatite, if that's what you're implying the plan is. Indeed, there may be free H2 available at locations such as the Ina D-pseudo caldera.

Quote from: gbaike
One has the peaks of eternal light. Plus by connecting solar farms in different regions
one can get continuous electrical power. So with one area of peaks of eternal light one can get
80% or more of time with sunlight. Or 50% of time elsewhere on Moon has 2 weeks of darkness.

The only real advantage of the polar location per se (that is, other than its proximity to permanently shaded craters) is the relatively mild and constant temperature profile. The constant solar is nice, but the problem is it's coming in at 90 degrees, so you can't just lay your panels on the ground; you need to put them on masts, and then you'll have the problem of your panels shading each other. Also, most people vastly underestimate the power requirements of an industrial fuel production plant producing fuel in truly game-changing quantities. This is a long winded way of saying you'd probably want to use space-based solar power.

Drilling for volatiles trapped at  shallow levels would require VASTLY less infrastructure. A single 20 mT lander could deliver a drilling rig capable of drilling down 100 m or more.

The only reason we don't already have commercial lunar water mining is because the lunar poles [or moon generally] has not been explored to find minable sites.

It possible that there is water 100 meter below the surface of the Moon- somewhere at the surface, but this seems like a more difficult thing to explore in order to find. Plus, once you find it by drilling for it, you are mining it.

My idea is to do what Congress has already passed into law- explore the Moon and then explore Mars.
What I think would allow NASA to start this, is a cheap, quick and low cost lunar exploration which determines if and where there is sites which are potentially commercially minable.

So tomorrow or anytime in future, NASA could get approval for lunar exploration mission which will have it's
total program cost of 40 billion and to be finished within 10 year of the start of program.
The program includes:
Developing orbit depots to an operational status- a depot only capable of storing and delivering LOX, is adequate.
Lunar robotic exploration program which explores Moon.
Finish lunar exploration program by landing crews in regions previously robotically explored, to do a more thorough exploration of region, and returning lunar sample to Earth for further analysis.
And then, Start Mars program.
And to start the Mars program, NASA can't spending billions per year on ISS nor doing things costing billions on the Moon.
So Lunar exploration will occur at same time as ISS program- and ISS program has to do something with ISS
by the time of the start of Mars program- and I would not suggest NASA de-orbiting ISS, but find some other way.
So if NASA explores the Moon, and finds minable areas on the Moon, then commercial lunar water mining can occur while NASA explores Mars.
If NASA can't find minable lunar water on poles or even if they do, perhaps if [cost is low enough] NASA or some other party can search for water under the surface of the Moon. Or if commercial lunar were to begin it's possible one will have commercial lunar exploration of the Moon which could find minable water below the surface. Or most exploration for mining is done commercially on Earth- and commercial lunar mining is having success, this would help towards funding of further exploration which is not required to be done by NASA.

As for making masts for solar power, we were making sailing masts centuries ago, and on the Moon there is no wind and one has 1/6th gravity. Put panel high enough and one can operate under the bottom section panels- or you don't have to have long cables to bring power to split the water. So you focus on having a vertical solar panel array, which can be hundred or more feet high.
And ultimately one wants a widely space grid network which has constant power available for the network of solar arrays. And I suppose that at bottom of mast one can increase the voltage for transmission over longer distances.
« Last Edit: 05/24/2016 08:05 PM by gbaikie »

Offline Robotbeat

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Re: Impact of lunar free water on Exploration Architecture
« Reply #37 on: 05/24/2016 08:11 PM »
Heck, on the Earth, the oxidizer is (chemically) free in the air and the fuel is (chemically) free in the ground.

The same is true of the Moon. Nobody is talking about extracting water from apatite, if that's what you're implying the plan is. Indeed, there may be free H2 available at locations such as the Ina D-pseudo caldera.

No, it's not. There are not vast quantities of easily accessible oxygen and fuel (hydrogen or methane) on the Moon. I'm talking stuff that isn't in trace quantities and stuff that doesn't require electrolysis (or similar) to acquire.
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Offline savuporo

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Re: Impact of lunar free water on Exploration Architecture
« Reply #38 on: 05/24/2016 08:48 PM »
There are not vast quantities of easily accessible oxygen and fuel (hydrogen or methane) on the Moon...
Did I miss something? There is new data or interpretation of existing data that would have conclusively disproven the more extreme hypothesis of exposed water ice in PSRs?
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Offline savuporo

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Re: Impact of lunar free water on Exploration Architecture
« Reply #39 on: 05/24/2016 09:47 PM »
And what is extreme about water ice being stable at 30 K?!?
Its extreme in the context of full range of current hypotheses to explain the existing data about composition of surface materials in PSRs. Ice rinks at the crater floors continue to be possible, but unlikely. The reality will likely be something more modest.

EDIT: the point of my post was, that we currently cant tell what exactly is there with high certainty, and we definitely cannot tell how easily accessible or usable any of the materials are. Further data needed.
« Last Edit: 05/24/2016 09:50 PM by savuporo »
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