December 21, 2010
Can we afford to return to the Moon?
Resource map of the north pole of the Moon (from Spudis and Lavoie, in press)
We are almost at the end of a year that has seen major changes in our space program. We have in hand a report from a “blue ribbon” Presidential committee that concluded that Project Constellation, the architecture NASA had chosen to implement the Vision for Space Exploration, was not affordable at current funding levels but might be accomplished with an increase in the agency’s budget, on the order of an additional $3 billion per year. The committee presented architectural alternatives to Project Constellation, one of which eliminated the Moon in favor of a “flexible path” that allowed human missions to other destinations (e.g., an L-point, an asteroid) beyond low Earth orbit.
I take issue with several points in the Augustine report and have commented on them at length in several previous posts of this blog. But now that the dust has settled and we have a “new direction” for our space program, its two principal deficiencies are evident. First, by discarding the clear strategic direction provided by the VSE, we have entered an era of uncertainty and aimlessness of purpose in our space program. This institutional drift is reflected in nearly daily stories about NASA – new missions studies, new launch vehicles, the endless personal backbiting amongst the space internet cognoscenti. Second, the assertion of the report that return to the Moon is “unaffordable” is simply wrong. How you go to the Moon and what your mission is there determines cost and all the committee looked at were cost models for the existing program and minor variants on it.
I have made both of these points here and elsewhere and many were quick to challenge me to show how we could go back to the Moon under the conditions and assumptions of the Augustine committee. Rather than shut up, I now put up. I have submitted a paper for publication in the Proceedings of Space Manufacturing 14, the conference in late October sponsored by the Space Studies Institute. My co-author Tony Lavoie and I have developed an architecture that returns America to the Moon with a specific mission in an affordable way. Our paper has now been accepted for publication, so I am posting a pre-print of it on my web site and will summarize our findings here.
One of the biggest problems with NASA’s implementation of the VSE was that they never understood why we were going to the Moon. I base this assertion on their own statements, actions and publications. Early workshops were held by the agency to develop a rationale for lunar return. The Exploration Directorate issued a poster showing six “themes” for lunar return, but no one at the agency could state their mission in one sentence. At a Congressional hearing in 2009, the acting administrator of NASA said the he did not understand what “return to the Moon” meant in terms of mission objectives and activities.
The agency took the position that they were merely transportation agents – that it was up to the various “user” communities to decide that activities were to be undertaken on the Moon. As a matter of fact, the Vision itself very specifically laid out what was to be done on the Moon and even how to approach it. The purpose of lunar return is to learn the skills and develop the technologies we need to live on another world. The Vision specifically mentions that one skill we need to acquire is the use of extraterrestrial resources to make both exploration and human presence permanent and sustainable.
NASA ignored this direction. There are many reasons why they did this, but I believe that the main one was they did not know how to create sustainable human presence on the Moon using its resources and were concerned that such a thing might not be possible. But building large rockets is certainly possible – history documented that. So the VSE morphed into a rocket-building program, an Apollo Redux because that’s what the agency (allegedly) knew how to do. The only problem was that we do not live in the Apollo era and the space program no longer gets 7% of the federal budget.
The approach we take in our new architecture is to: 1) define the mission clearly and directly; and 2) design an architecture that accomplishes the mission in small, incremental and cumulative steps. These last three adjectives are important: Steps must be small to be affordable, not only under existing budgetary constraints but also under possible lower budgets that could be necessitated by national economic conditions in the future. The steps should be incremental, meaning that each step adds some asset or capability and must work in tandem with previous equipment and operations. Finally, the steps must interlock such that the whole is greater than the sum of the parts. The architecture cumulatively increases features and capabilities with time.
We take as our mission the original Vision for Space Exploration. We go to the Moon to establish a permanent human presence there and a reusable, refuelable, and extensible transportation system to support such presence. Once established, we will have a space faring system that can not only routinely access the Moon, but all other points in cislunar space and beyond, including the L-points and near-Earth asteroids.
How do we accomplish all this? One of the principal advantages of the Moon as our first goal beyond LEO is that: 1) it has the material and energy resources we need; and 2) it is both close and accessible. This latter set of attributes is more important than you might think. The closeness of the Moon allows us to directly control and operate robots on the lunar surface; the time-lag between action on Earth and execution on the Moon is only a bit over one second. We can operate machines on the Moon in near real-time. Additionally, we can send space vehicles to the Moon at virtually any time. No other space destination is so easily and readily accessible.
The key to making all this work is the use of teleoperated robotic machines. We go to the Moon robotically first and later with people. These robots are controlled by people on the Earth. They prospect for resources, test techniques, evaluate product yields, set up processing plants, and begin harvesting lunar resources almost immediately. The extracted products are cached on the surface for future use. The entire lunar outpost is set-up and made operational by these robotic machines.
Our architecture is designed so that time is a free variable. We make constant, steady progress toward our goal; in fiscally lean times, we go slower, but we can accelerate the schedule if more money is available. Making individual steps small and incremental permits this approach – we are not waiting for the development or advent of some “magic carpet” piece of equipment to fill a major hole in our plan.
So what’s the bottom line? Our plan creates a fully functional, operating lunar resource outpost capable of manufacturing 150 metric tonnes of water per year. In addition, we develop a reusable space faring system, one fueled by lunar propellant and expandable to support missions to the planets and destinations throughout cislunar space. We do all of this under the budget guidelines provided to the Augustine committee by NASA; total aggregate funding for this program is less than $88 billion (real-year dollars), with peak funding of $7.1 B in Year 11. Although schedule is flexible, we achieve our primary mission goals by the end of year 16. We have had our assumptions, mass estimates and costing examined, reviewed and validated by a variety of space experts, including the Engineering Directorate Mission Analysis Group at NASA’s Marshall Space Flight Center. This program architecture does what Project Constellation did not: it returns America to the Moon with a legacy of real and permanent space faring infrastructure.
In contrast to the current drift of our space program, the original Vision for Space Exploration set a strategic direction and path that made sense, giving us an expanding sphere of human reach beyond low Earth orbit. The idea that America cannot afford space is ludicrous – we have the world’s largest economy and the amount we spend on space is now less than one-half of one percent of the federal budget. But whatever we spend on space, we should expect to get something in return. A lunar outpost and space transportation system gives us a return on our investment; a program of one-off, stunt missions does not.
The path forward into the future is still open to us.
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Pingback by Tweets that mention Can we afford to return to the Moon? | The Once and Future Moon -- Topsy.com — December 21, 2010 @ 10:59 am
Dr Spudis:
I agree with what you propose. Unlike most other schemes, it is coherent and actually makes sense.
Mike Griffin was tasked with too many objectives (keep the problematic shuttle flying, finish the ISS, perform amazing science missions… oh and by the way, design and test a new launch architecture that will allow NASA to fly to the ISS by 2015, and to the Moon by 2020, all with a shrinking budget. His decision to cancel the Lunar robotic missions was forced upon him by shuttle and ISS cost overruns, and the need to prioritize the most immediate milestone, ISS crew flights by 2015.
NASA needs someone like you at the helm, keeping it on course, rather than being distracted and detoured by unnecessary and destructive politics.
Comment by Nelson Bridwell — December 21, 2010 @ 1:48 pm
Nelson,
Part of the problem with the way NASA approached the VSE was that they never understood WHY they were tasked to go to the Moon, even though the Vision specified exactly why. This was pointed out to many in the agency repeatedly. If you understand what you’re trying to do, it influences the architectural choices you make.
Thanks for your continued readership.
Comment by Paul D. Spudis — December 21, 2010 @ 2:00 pm
I can’t wait to read your paper and take a look at your lunar architecture!
I’ve always liked the idea of robotically setting up a manned facility on the lunar surface before humans arrive there. I see no reason why NASA can’t utilize the launch resources of a company like the ULA in order to start deploying exploratory rovers, excavation machines, and even water processing plants on the lunar surface within the next 5 years.
Still, I have a preference for deploying large habitat modules (vertical can shaped structures perhaps 5 to 6 meters in diameter and maybe 3 to 6 meters high) on the lunar surface that can be interconnected with each other in order to create a spacious and more psychologically appealing environment for the astronauts. And I see no reason why such a facility couldn’t easily be appropriately shielded from galactic radiation (even deeply penetrating and potentially brain damaging heavy nuclei) within a surrounding ziggurat of simple regolith containing boxes or fences by using lunar regolith excavating robots.
Also, if it turns out that the Moon’s 1/6 hypogravity environment is deleterious to human health then habitat modules with 5 to 6 meter in diameter internal centrifuges could also be sent to the Moon to keep the astronauts healthy. But I strongly believe that a heavy lift vehicle will be needed to do that. So I hope such heavy lift vehicles, already commissioned by Congress and the President, will be ready by perhaps 2018 in order to begin deploying such large habitat modules.
But that does not mean that we can’t start utilizing robots to explore, excavate, and to start sintering the lunar surface in preparation for routine manned landings and, of course, start extracting water from the lunar surface at the poles and perhaps manufacturing and liquifying oxygen and hydrogen for rocket fuel. There’s no reason why we can’t use existing Atlas V and Delta IV heavy rockets to do that. I’m pretty sure Boeing, Lockheed, and the ULA would be extremely happy if the President and Congress moved in that direction$$$$
I also don’t see any reason why small video rovers can’t be deployed so that people all over the Earth can watch these base building activities on the internet along with unmanned and eventually manned landings on the Moon from the perspective of the lunar surface. The space pioneering of the Moon would be an excellent reality TV show, IMO!
Comment by Marcel F. Williams — December 21, 2010 @ 2:18 pm
@Nelson Bridwell
” NASA needs someone like you (Dr. Spudis) at the helm, keeping it on course, rather than being distracted and detoured by unnecessary and destructive politics.”
I strongly support that idea!!!
Comment by Marcel F. Williams — December 21, 2010 @ 2:22 pm
I never thought Constellation had any problems that couldn’t been fixed with a few tweets. But, having said that, the silver lining of the destruction of our human exploration program is that we can have a fresh look at the problem of returning people to the Moon. Here I think Paul and company performs brilliently. I may have a few nitpicks and reservations (mainly in the early reliance on fuel depots), but on the whole I like the plan. Bravo for a serious effort.
Comment by Mark R. Whittington — December 21, 2010 @ 2:48 pm
Marcel,
Thank you for your comments. I have no prejudice regarding hab sizing, except my intuition that putting them down on the Moon is more of a launch volume consideration than a mass issue. The temptation is to use inflatables, but with all their supporting and internal structures and complexity of deployment, they start to lose their appeal rather quickly.
Heavy lift is good for large volume structures and can carry additional cargo to boot. However, as we state in the paper, we use medium heavy lift in this architecture only for cost estimating purposes – we are happy to consider other LV approaches.
It’s all about the “mission” not the “means.”
Comment by Paul D. Spudis — December 21, 2010 @ 2:52 pm
Brilliant piece Paul! However I doubt that NASA will ever implement it due to the fact that it is (and has always been) a political organization.
It was birthed in the cold war and now serves the government for prestigious albeit frivolous reasons (i.e. ISS used more for international “cooperation” than helping us actually live off world).
I was thinking something more of the sort of robots utilized by the private sector (something the Google Lunar X-Prize could help jump start) as well as Bigelow Aerospace bases.
Anyways thanks for the paper! I’ll be pouring over it as going to the Moon is IMHO the only rational option for getting to the stars without going broke.
Comment by Darnell Clayton — December 21, 2010 @ 6:14 pm
Paul,
Excellent work! It’s a very well thought out and reasoned plan. I just read it through for the first time and intend to go back and re-read it later and perhaps post more specific comments.
Ideally, this should be done as a cooperative project with India, Canada, Australia, UK, ESA, Russia and China joining with the USA. As a percentage of world GDP, it’s microscopic in terms of cost, but with a long term payoff that’s enormous. If the USA goes it alone, though, I can see this generating massive profits in the long run when we charge other nations for refueling and other services. In fact, I think selling this to Congress as a for-profit enterprise might be a very good strategy.
Great work and thanks for a very inspiring Christmas present to end a bumpy year in space!
Comment by Bob Carver — December 22, 2010 @ 2:27 am
Darnell,
However I doubt that NASA will ever implement it due to the fact that it is (and has always been) a political organization.
This is certainly true enough, but we’ve always had “political” organizations throughout our history and given sufficient motivation and some imperative mission, they still are able to accomplish their assignment. This is one of my main points: know what you’re trying to do and why — THEN devise the approach you want to take to do it.
Comment by Paul D. Spudis — December 22, 2010 @ 4:03 am
Bob,
Ideally, this should be done as a cooperative project with India, Canada, Australia, UK, ESA, Russia and China joining with the USA
One of the great advantages of the small, incremental approach is that its structure lends itself well to both international and commercial participation. There are multiple and recurring opportunities for such participation; it doesn’t all have to be locked in up front.
Comment by Paul D. Spudis — December 22, 2010 @ 4:05 am
Sir, your subject is really interesting and inspiring for the generation to come. NASA has the best name and fame, everything, The Apollo missions are the living evidence and after that LRO is coming, with such a boon, what else the Government and its people would like to wish more than these. At the same time, “Return to the Moon” as the name and theme suggests, is an incarnation of human science for those who love to live in science in the history of mankind. I myself, as a research fellow, enjoy in my work, such a planetary studies are just unimaginable and extra-ordinary.
Comment by Guneshwar — December 22, 2010 @ 9:22 am
Mr. Spudis has hit the nail squarely on the head when he concludes that *infrastrucure* is badly needed in order to make space an affordable, and thus sustainable, venture.
I would take the premise a step further and point out that it is not in the mission statement of NASA (or any other government agency) to build space-borne infrastructure; they are an R&D organization. We must look to the commercial sector to lay foundations upon the beachheads secured by NASA.
Comment by J. Paul Douglas — December 22, 2010 @ 12:20 pm
Very interesting plan. The presumption that the lead-in work should be done telerobotically is excellent. That is, you can do ISRU demos as well as lunar outpost development without putting astronauts on the lunar surface. That makes the plan much more resilient to funding uncertainties. To the extent that people want to consider lunar exploration an international competition (e.g. with China), the competition becomes one of real lunar development, rather than who can be next to put bootprints down.
What are the next steps for having the agency consider such a proposed plan?
Comment by Herman — December 22, 2010 @ 12:58 pm
The gold and silver in the LCROSS plume has stirred up some noise. But, in my opinion, the most valuable lunar resource is water.
“Instead of the current design-build-launch-discard paradigm of space operations, we can build extensible, distributed space systems, with capabilities much greater than currently possible.”
This is what we need to shine the spotlight on. Hydrogen and oxygen in LEO and EML1 & 2 would be a profound game changer.
Of course this needs propellent depots. That’s why I like Zegler and the ULA boys. Taking their route, we will have lots of depot experience by the time lunar propellent comes online.
Comment by Hop David — December 22, 2010 @ 1:52 pm
Herman,
What are the next steps for having the agency consider such a proposed plan?
We are on the course we are on (i.e., doing nothing) for at least the next few years. However, at some point, the agency will be under new management. I suspect that at that point, the need for a shift in strategic direction will be even more obvious than it is now. Then we might see the advent of something productive.
Comment by Paul D. Spudis — December 22, 2010 @ 1:53 pm
Humans wouldn’t arrive until Mission 16? Preceding that would be robotic water mining and export? I am hoping this would be the case. But I wonder how much R & D it would take to make robots up to the task. If we did manage to develop robots this capable, it seems to me they would have many industrial and military applications right here on earth.
Comment by Hop David — December 22, 2010 @ 2:11 pm
Hop,
We schedule human missions late in the plan and do most of the outpost set-up and initial ISRU processing prior to their arrival via teleoperated robots. The produced water is not exported, but stored on the Moon for use by people when they arrive. The robotic technology we need to do this exists today.
Comment by Paul D. Spudis — December 22, 2010 @ 2:41 pm
In the ‘new and improved’ NASA plan, NASA will have an Exploration Robotic Missions Program (xPRM). However, there is not enough money appropriated to this program to do much more than studies. And, their focus seems to be on missions to near-earth asteroids. Though there is talk about xPRM missions to the Moon and Mars, there is no money for these to happen anytime soon. Unless things change in Congressional language and appropriations, we’ll have to be content with watching other countries explore the Moon, (something we once could do), or private companies having a try at the Google Lunar X-Prize. History has shown that the ones who get to the ‘New World’ first reap the most rewards from the natural resources and resulting commerce.
Comment by JohnG — December 22, 2010 @ 2:46 pm
@Paul:
“Mission 2″ concerns me. Are you suggesting that surface prospecting for adequate ice ore is a task we can expect to complete in a single go? If so, then either water is easy to find and exploit or we’re about to undergo a revolution in geological survey right here on Earth. If not, isn’t this increment exposed to exceptional risk for costs blowing up out of control?
Comment by Presley Cannady — December 22, 2010 @ 3:10 pm
“The robotic technology we need to do this exists today.”
I recall watching a YouTube video with you, J. S. Lewis, and some other folks on a space resources panel. There was a mining guy from Canada who thought telerobotic lunar mining was doable.
If the robotic technology already exists, it becomes a much more plausible proposal. Could you point to some of the existing robotic technology that will make this possible?
Comment by Hop David — December 22, 2010 @ 3:11 pm
@Paul:
Or is remote sensing just that much better at identifying promising prospects on an airless rock like the Moon?
Comment by Presley Cannady — December 22, 2010 @ 3:16 pm
@Hop:
This guy?
http://robotics.estec.esa.int/i-SAIRAS/isairas2008/Proceedings/POSTER%20SESSION/m057-Baiden.pdf
Comment by Presley Cannady — December 22, 2010 @ 3:18 pm
Presley,
Are you suggesting that surface prospecting for adequate ice ore is a task we can expect to complete in a single go?
More or less a “single go.” We put identical prospecting rovers at both poles and they survey the areas near the quasi-permanent sunlit zones. They operate continuously, recharging their batteries at the fixed landers when necessary, until we have thoroughly mapped their near field areas for water content. From the data they obtain, we select the mining prospects. This prospecting goes on for at least a year, maybe longer. We assume only 10% water to make our architecture work; I think that existing data support at least those concentration levels and probably much greater ones.
If we’re wrong and there’s not enough water at that locality, all we’ve spent is the money for those robotic missions and we can go back to the drawing boards to re-architect the plan.
Comment by Paul D. Spudis — December 22, 2010 @ 3:19 pm
@Paul:
Robotic alternatives don’t have to be more capable than existing extraction technologies and processes used on Earth for the plan to make sense (initially). They just have to be cheaper than applying the usual methods on the Moon.
Comment by Presley Cannady — December 22, 2010 @ 3:21 pm
Hop,
Could you point to some of the existing robotic technology that will make this possible?
We see some of it on current missions, such as the Mars rover, but telerobotics are in wide use in many hazardous or remote operations on Earth. The mining industry is just starting to get into this technology — most of it in current applications deals with nuclear power, deep sea exploration and telemedicine.
Comment by Paul D. Spudis — December 22, 2010 @ 3:24 pm
@Paul:
Is 1 rover a launch a hard upper limit off-the-shelf right now, or are there alternative payload, launch, and rendezvous configurations to expand coverage areas?
Comment by Presley Cannady — December 22, 2010 @ 3:26 pm
@ Cannady
Perhaps a prospector mission will be carried out sooner rather than later:
http://sites.nationalacademies.org/xpedio/groups/ssbsite/documents/webpage/ssb_059306.pdf
Sure hope they use the more expensive version that’s not limited to a 4.5 day battery
Yes, Greg Baiden’s the guy. Marcel had pointed me to this video:
http://www.ustream.tv/recorded/10752525
Comment by Hop David — December 22, 2010 @ 3:41 pm
Is 1 rover a launch a hard upper limit off-the-shelf right now, or are there alternative payload, launch, and rendezvous configurations to expand coverage areas?
No, you can send two rovers at a time – it all depends on the launch vehicle. As we say in the paper, we are open to many LV solutions.
Comment by Paul D. Spudis — December 22, 2010 @ 3:45 pm
@Paul:
Any come to mind? My impression this paper reasons an upper limit on an affordable lunar return strategy, particularly one that is most hospitable to certain interests in Congress.
Comment by Presley Cannady — December 22, 2010 @ 4:08 pm
Presley,
My impression this paper reasons an upper limit on an affordable lunar return strategy
Funny — I look upon it as a lower limit. This is the minimum of what you do on the Moon to give you a reusable, extensible space faring system. We can easily do less, but we won’t get the end state objective, which is: 1) permanent human presence on the Moon; and 2) a cislunar transportation infrastructure to support it, allow routine access to cislunar space, and lay the groundwork for planetary missions to follow.
If you are alluding to the Heavy Lift Vehicle in the architecture, as we explain the paper, this was only assumed for the purposes of estimating cost. It is not a critical part of the lunar return strategy.
Comment by Paul D. Spudis — December 22, 2010 @ 4:39 pm
@Paul:
I should say an upper limit within Augustine’s projected budget run-outs. Presumably you hope to revisit trades within each increment insofar as options permit to reduce cost even further.
Comment by Presley Cannady — December 22, 2010 @ 5:52 pm
@Presley;
I think the point that we are trying to make is that this architecture is “a” solution that closes for the funding that was defined to the Augustine Commission as being available. As well, the individual cost numbers are more of allocations such that Reserves are actually part of the allocation. That is to say, performance is reduced when issues arise that require more money than the initial estimate of Reserves for each mission. We have put some performance margin in the estimates, although not a whole lot, but if the budget is there, and we are reasonably diligent to hit the critical technical challenges with early development work, and we are able to adapt to what we find in the early robotic missions, this architecture or one like it has a good chance to succeed. It might eventually take a little longer if we have a bad decade in development, but the point is that schedule is flexible, funding is relatively fixed, and we make progress on a well thought-out path toward meeting a strategic objective, consistent with a known budget profile.
Comment by Tony Lavoie — December 22, 2010 @ 9:43 pm
This is very much doing something cause we CAN do it, without much thought for WHY?
Certainly we could use the resources of the Moon to live there if we really wanted, but we could also live under the Ocean if we really wanted, or dig down to the mantle and use those resources. Much of the Earth is not even inhabited by people and it has much more abundant and easy to access resources than the Moon.
If the purpose of going to the Moon is to do good science, teleoperated robots would do a much better job without risking lives for much cheaper and the only resource they require is power which they can easily get from the Sun.
If the purpose of going to the Moon is to spread life, then the Moon makes little sense. Mars is a much better candidate for that purpose. It has vastly more water and volatiles, an atmosphere, more gravity, 24 hour day/night cycle, most of the chemicals needed for life….etc etc etc
Maybe I am a little cynical, but I’ve seen the sun, moon and stars promised a million times when it comes to space. I’ve a hunch that using the Moon’s resources will end up being actually more expensive because of all the equipment and infrastructure that has to be managed. The Shuttle was “reusable”, but look how expensive that ended up being. So is the ISS. I’d like to be wrong about this!!!
Comment by Gregori — December 22, 2010 @ 11:29 pm
Dr. Spudis,
Thank you for your work. This approach is the right one. First teleoperated robots, harvesting lunar water ice, and preparation for a manned return…it’s the smartest way to go. Its very close to the Plan for Sustainable Space Development which I have been advocating for some time. I’ll comment more after going through your paper in detail.
Initially, my response is both excitement but also a bit of disappointment. The plan itself is very good. But at $88 billion over 16 years puts it at about 29% of NASAs budget. I was hoping for an approach which would cost considerably less and would yield H2/LOX at LEO. It seems to me that this means that you either have the Flexible Path or this new Plan – you canot have both, right? If so, then I think that its going to be quite an uphill battle to get this accepted as the new direction.
I really wish that this Plan had been out there a year ago while NASAs new direction was being considered. I expect that in three years there will be hand-wringing about cost overruns and delays in the development of the HLV. Unfortunately, instead of “losing” the money invested, Congress might “double down” and throw good money after bad and end up with the worst situation which is to tie up another generation or two with an unneeded HLV and maintaining a workforce to launch it on missions seeking to maintain America’s “leadership” by conducting really pointless missions.
I hope that there might be a way to accomplish your same goals but at less cost. But if this is the only way to develop space sustainably, then we need to spend the next two years building a strong coalition of advocates so that the next administration will be pressured to change our direction even at loss of investment to that point.
Comment by JohnHunt — December 22, 2010 @ 11:48 pm
Paul Spudis, you are a genius!! Yes, robotic prospecting expeditions at first. Once a new President of the U.S. gets inaugurated, come January 2013, the stage will be set for the new leader to restore the Orion-Altair spacecraft structure, and hence restore the manned Return-to-the-Moon mission.
Comment by Chris Castro — December 22, 2010 @ 11:50 pm
Gregori,
This is very much doing something cause we CAN do it, without much thought for WHY?
Did you actually read the paper we wrote? We specifically addressed the reason WHY — to create a permanent, cislunar space faring infrastructure based on the use of lunar resources. Once we have that, virtually any other mission you can imagine is possible. For immediate use, we create this system to routinely access not only the Moon, but all of cislunar space, where all of our satellite assets reside.
Comment by Paul D. Spudis — December 23, 2010 @ 3:24 am
John,
I was hoping for an approach which would cost considerably less and would yield H2/LOX at LEO. It seems to me that this means that you either have the Flexible Path or this new Plan – you cannot have both, right?
That’s right — we propose this plan in place of, not in addition to, the current “direction.” The difference between the two is that with this plan, you get something for the money.
If so, then I think that its going to be quite an uphill battle to get this accepted as the new direction.
Of course it will be — it has been for the last 30 years. We’ve gone down dead ends and wasted time and money in space before. But I happen to think it is worth fighting the battle. If I didn’t, I’d get out of the business.
As far as the “new direction” goes, that will probably last about as long as the current administration does. The new authorization bill for NASA specifically mentions the Moon and cislunar space so even officially, the Moon is still part of our “realm” in space.
Comment by Paul D. Spudis — December 23, 2010 @ 3:28 am
As I said before, this is an excellent plan, and one that makes a lot of sense with regard to sustainability. But one thing I worry about, policy-wise, is that human spaceflight doesn’t have a clear role to play in it for at least fifteen years. Is that going to be marketable for a plan that is aimed at long term human space flight?
That is, during these fifteen years, what is our human space flight program going to look like? Back and forth to ISS for fifteen years? Maybe a NEO visit? (Actually, I think the NEO visit is an unreasonable goal, both with regard to technology and rationale. I suspect it’s not going to happen for a LONG time.) The end objective here is permanent human presence on the Moon, but this plan doesn’t get people out of LEO for a long time.
Comment by Herman — December 23, 2010 @ 9:52 am
during these fifteen years, what is our human space flight program going to look like? Back and forth to ISS for fifteen years?
That’s pretty much the only option, isn’t it? Of course, the difference is that in our lunar return architecture, after 15 years we’ll be ready to go to the Moon. After 15 years in the current Program of Record, we’ll be ready to continue going into low Earth orbit. Perhaps we’ll be ready to do a stunt human mission to an asteroid, but I wouldn’t bet on it.
Comment by Paul D. Spudis — December 23, 2010 @ 10:01 am
@Gregori,
The real issue with Mars is its distance away, which directly relates to cost and risk. From an engineering perspective, the Delta V difference is substantial, and the cost difference is very large. Also, the time lag would be enough to be much more difficult if not impossible to execute interactive operations between the Martian surface and the operators on Earth; Science use of pre-stored command sequences doesn’t seem to be a good idea at this point due to the nature of the tasks performed in such an architecture. The Moon might not be so “ideal” compared to Mars resource and curiosity potential, but it is close enough to try approaches which investigate ISRU as a means of learning to live off-planet. Further, if we do a good job learning how to use local resources, then the rocket equation leads us to say that the Moon’s surface would be a better place (as opposed to Earth) to get fuel for the journey out. We honestly don’t know yet if that is viable. We also don’t know yet if the concept of local fuel production as part of a sustained human campaign to a planetary body is viable. The point is to investigate it locally (read, pick a place that is close so that you minimize cost and maximize chance for success while we are learning how to do it or even if it can be done). Overlaid on top of that is a desire on the part of many (no, not all) to go the Moon and “explore/exploit”, and you have the full rationale for the Lunar Architecture.
Comment by Tony Lavoie — December 23, 2010 @ 10:30 am
This sounds like an excellent baseline for a logical future space policy, and one in which commercial concerns could doubtless slot in appropriately.
If there is backing for this kind of multi-year program, US-led space exploration would start to make sense for the first time in many years.
Bravo.
Comment by David Jefferis — December 23, 2010 @ 11:17 am
Bravo, Paul! I heartily approve of your teleoperation-first approach.
Comment by Ron Menich — December 23, 2010 @ 3:29 pm
I just got done reading through the article. I appreciate the solid work that both of you have done on it. There’s a lot there to chew on!
As an idea, maybe instead of waiting until the next administration, maybe NASA, et al could be eased into this new Plan. As you have pointed out so well, the numerous small, bite-size steps are good for commercial and varible funding situations. BUT, it might also be good for a free-standing and/or prize approaches.
I have been amazed at the degree to which NASA continues awarding money for various lunar-related activities (regolith extractor, lander, data). If they have been given a new direction, why do they seem to still be interested in the Moon? Specifically, the Northrop Grumman Lunar Lander Challenge was for what specific purpose? Is this a lead-up to a prospecting mission?
So, are there components of this new Plan which could be prized-out in the near-term (e.g. 2-3 yrs). Solar-powered water electrolysis and/or solar-powered maintenance of cryogenic fuel would be my first choice. Separation of water from icy regolith simulant would be another great one. Demonstration of teleoperations would be another of my choices. None of these would be terribly expensive if done on Earth. In fact, just how much of these lunar operations could be demonstrated at a lunar replica environment on Earth? The more we keep this Plan in the news, the greater the cry to switch to new Plan as the current plan starts to wander.
And it doesn’t necessarily have to be NASA to put up the money for the challenges. Any step that we make towards this Plan strengthens the argument that we can and should proceed along the path. Also, as the HLV starts running into delays and budget overruns (notice how I just presume these things), then any inexpensive, pay-for-achievement, accomplishments for this Plan would make it seem as though this Plan will be much more cost-effective than business as usual.
Comment by JohnHunt — December 23, 2010 @ 11:28 pm
@Gregori:
We’re (hopefully) returning to the Moon for the same reason Columbus set out to find a western route to India: to get rich. The Moon is a reasonable point to start expanding into the solar system because it’s the most immediately accessible source of stuff we need for permanent settlement off world. From the Moon, you can reach a wealth of destinations far easier to reach and exploit (and far more readily abundant) than Mars. Volatiles? You’ve got comets and carbonaceous asteroids.
And once you’re out of the 8 km/s trap that is Earth (and eventually beyond the Moon’s 1-1/3 km/s well), why doom yourself to Martian gravity? Once you’ve licked living and moving about the Earth sphere, you’ve got access to all the material you need to house several orders of magnitude more people than currently live on Earth in habitats designed to make life as comfortable as you could imagine.
Comment by Presley Cannady — December 24, 2010 @ 12:15 am
Gregori had written “Mars is a much better candidate for that purpose. It has vastly more water and volatiles, an atmosphere, more gravity, 24 hour day/night cycle, most of the chemicals needed for life….etc etc etc”
And North America has vastly more resources than England. Would that justify Europe skipping England and going straight for the Americas?
The are substantial CHON deposits at the moon, enough to support many people as well as to supply cislunar space with propellent for centuries (if not millennia) to come.
If the largest quantities of CHON is the deciding criteria, Jupiter would be the obvious choice.
Comment by Hop David — December 24, 2010 @ 12:30 pm
I was not in favor of going back to the moon until water, and more water was discovered. I am a colonization proponent and believe in the survival imperative, planetary protection, etc.
I became interested in space after reading “project orion” by Dyson several years ago. Since then I have been reading up on space exploration and have come to some conclusions.
But nobody else seems to agree with me. Paul and Tony, I would be interested in any comments.
1. The heavy nuclei component of galactic cosmic radiation means hundreds of tons of shielding will be required for any long duration human spaceflight missions beyond earth orbit. Dr. Eugen Parker wrote an article in SA magazine about this and specified a water shield of 5 meters of water, which works out to about 400 metric tons for a small capsule. Unlike everyone else, I accept this and am not dancing around it. Along with the radiation problem is zero G debilitation. So I also accept the requirement for artificial gravity. What results is a 500+ ton water filled ball with an air filled compartment in it. The simplest way to create gravity is with 500+ tons at the other end of a tether and the two masses spinning.This is the “Minimum Spaceship.”
2. The only viable propulsion system for a one thousand ton spaceship is atomic bomb propulsion. We certainly have enough bomb material and the shuttle side mount vehicle with a Launch Abort System (LAS) attached to a fissionables package could safely transport the devices into orbit. We have the propulsion and the protection required to fly in deep space.
3. This “Minimum Spaceship” design is what we need to be building and bringing up the water from earth is not very practical compared to bringing it up from the much shallower gravity well of the moon.
Thank you for your time.
Gary Church
Comment by GaryChurch — December 26, 2010 @ 6:26 pm
Gary,
Your idea is very imaginative, but I think that you are putting the cart before the horse.
Right now, even if we could built your spaceship, where would go and for what purpose? You describe a vehicle capable of very long-duration, deep space travel, but if you were to build it, what good would it be?
Our most pressing needs in space are closer by, here in “greater Earth” or cislunar space. Right now, we can just barely get into low Earth orbit (LEO). Yet our space “workhorse” — the satellite fleet that provides our communications, weather, remote sensing, science and national security — is largely inaccessible because they are largely in orbits beyond LEO. What we need is a space transportation system that can routinely access all of cislunar space, where these satellites reside. Going to the Moon to mine water to fuel such a system is the goal of our architecture.
In regard to you specific design points, there are alternatives to 400 mT of water shielding and atom bomb propulsion. I suspect the development of such a vehicle is not likely for a variety of fiscal, legal and technical reasons.
Thanks for your comment.
Comment by Paul D. Spudis — December 27, 2010 @ 4:10 am
@Gary
If you replace the water shielding with slush hydrogen, you could reduce the mass needed for cosmic ray shielding by 2 to 3.5 times. Therefore, a ship requiring 500 tonnes of mass shielding in the form of water would only require 143 tonnes of slush hydrogen (a form of hydrogen which would have a much lower rate of leakage). Sun shades, of course, could further reduce gaseous hydrogen leakage.
As far as interplanetary propulsion is concerned, I believe that light sails could do the job– especially if they’re launched from the Lagrange points and only have to travel to high Mars orbit which would significantly reduce the delta-v requirements. Once in Mars orbit, chemical powered crew exploratory vehicles could transport humans to the Martian moons or to low Mars orbit. But don’t be surprised if you find Spudis and Lavoie water depot and cryo-fuel production facilities already on the surface of Phobos and Deimos thanks to previous efforts on the Earth’s moon:-)
A square 10 kilometer on each side light sail (100 square kilometers in surface area)could achieve the delta-v requirements for Mars transfer orbit in less than 5 weeks carrying up to 1800 tonnes in mass– if launched from Earth-Moon L1. Because of the reduced sunlight and the slightly higher delta-v requirements, it would take longer than 5 weeks for the sail to achieve Mars capture orbit.
The latest carbon nanotube materials could reduce the total mass of such an aluminized sail to less than 100 tonnes. So such sails should be able to transport over 1500 tonnes of payload to Mars orbit in less than a year. That’s more than enough payload mass to provide astronauts with the appropriate amount of mass for radiation shielding.
The Moon would be an excellent source for slush hydrogen shielding for interplanetary journeys. In the long run, it might also turn out to be a lot cheaper to manufacture light sail material from factories on the Moon and transfer them to L1 than from Earth since there is plenty of aluminum in the lunar regolith and there are indications that there might also be sources of carbon at the lunar poles.
Comment by Marcel F. Williams — December 27, 2010 @ 9:51 pm
@Marcel
I think we discussed before; Hydrogen is very difficult to keep liquid and even harder to keep in slush form. The stuff is always going to be generating impurities exothermally from the radiation, exfiltrating (hydrogen seeps out of almost anything not welded) and has no utility at all compared to water. Water is easy to transfer, can be used in a life support system, is easy to purify, and as Dr. Spudis points out- is fairly easy to refine from lunar ice or regolith. Hydrogen is a better shield, but the difficulties and non-utility make water the ideal solution.
But….not to be a naysayer Marcel, liquid hydrogen is good stuff for superconductor applications. If there was another use for the hydrogen in an electric propulsion system as a coolant it might make the difference. But Diaz’ VASMIR is heavy, super complicated, and needs reactor output that is extremely high. In connection with this I had high hopes for Winglee’s plasma sail but have not heard anything about this concept- probably because coupling the sail cloud to the vehicle is not going to work out. The many-kilometer plasma cloud might have applications as a radiation shield and this might be play into a liquid hydrogen scheme. But that is alot of mights and I am talking about doing right now.
As for solar sails; not enough thrust. As is the case with most propulsion systems, there seems to be two poles; hi Isp low thrust and lo Isp high thrust. Diaz is trying to address this problem. My opinion is that the problem was solved by Stan Ulam in 1945 when he conceived atomic bomb propulsion. It is ideal for deep space propulsion (outside the magnetosphere). There is nothing else. Your solar sail technology does have application as an atomic bomb engine; the Medusa concept (from a scientist named Solem if I recall) uses a huge parachute/sail type device instead of the more conventional pusher plate in Nuclear Pulse Propulsion.
It seems to me the many ideas floating around- propellant transfer depots and solar sails etc. are applicable to the two technologies that are the only really viable near future paths to BEO HSF. Massive water shields and atomic bomb propulsion. With a Shuttle Derived Sidemount Heavy lift Vehicle to loft components and Lunar water to fill up the radiation shield, we could have true space ships on their way to the asteroid belt and outer planets in Ten years. Kind of like the moon program.
Comment by GaryChurch — December 28, 2010 @ 3:00 pm
Paul:
One thing we need to be cautious about is promising too much. Dan Goldin went before Congress and promised miracle cures and wonder materials as a result of ISS research.
Your proposal is much more realistic and concrete. ISRU looks very promising. However, we don’t yet have a detailed picture of exactly what we will find at the poles. Even if we were to learn that it was impractical, there will be serious benifits from a more detailed understanding of the composition and origins of the Moon. I therefore feel that the initial objective should be:
(1) Lunar Science, and
(2) to determine if ISRU of lunar resources would be both practical and benificial.
Thanks again,
Nelson
Comment by Nelson Bridwell — December 28, 2010 @ 4:53 pm
Nelson,
I agree and in fact, one of the advantages of a “small step” program is that you can modify the plan and direction if your understanding changes or your approach is shown to be infeasible. However, I still think that assessment of the viability of resource utilization is our top priority on the Moon. I’m not against doing lunar science “in the margins” along the way, but the issues and difficulty of water production have to be the principal “mission” on the Moon. If we can make that work, we’ll get all the other things as a matter of course.
Comment by Paul D. Spudis — December 28, 2010 @ 5:56 pm
I agree. That makes sense.
(1) ISRU.
(2) Lunar Science
And if, for any reason, we are are unable to make #1 happen, we will still want to pursue #2.
Comment by Nelson Bridwell — December 28, 2010 @ 7:35 pm
@GaryChurch
Water is obviously easier to sustain as mass protection against cosmic radiation than water is. But the weight penalty of water relative to hydrogen is significant when we’re talking about interplanetary travel. Water could double or triple the mass of a vehicle relative to liquid or slush hydrogen. Water shielding, IMO, is best suited for human occupied structures that are in a permanent orbit rather than for interplanetary travel– unless you’re using one of Buzz Aldrin’s interplanetary swing station orbits.
Liquid hydrogen leaks at a rate of 0.127% per day, 3.81% per month. Slush hydrogen leaks at a rate that is about 20 to 30 % slower than liquid hydrogen. Hydrogen leakage rate is also effected by proximity of the container to the sun. So the leakage rate would be significantly lower at Mars orbit relative to cis-lunar space. While sun shades and other passive mechanism could probably reduce leakage further, I believe that re-liquifying the ullage gases and pumping them back into the shield containers would the best way to mitigate and possibly even eliminate the leakage of hydrogen for radiation shields. Photovoltaics could provide the power for such cryogenic refrigeration units. You’d probably only need enough power to refrigerate a few tonnes of ullage hydrogen per day.
The speed and the ability of a light sail to move significant amounts of mass depends on the size of the sail and the mass of the sail and its proximity to the sun. But, unlike a rocket engine, a light sail is constantly accelerating for weeks and for months or for years. So a light sail can potentially travel much faster than any rocket which is why there is so much discussion about using light sails for interstellar travel.
The Japanese light sail, IKAROS, that is currently headed for Venus has a reflective surface area of about 200 square meters. The sails, I’m talking about would have reflective surface areas of about 100 square kilometers yet could still weigh less than 100 tonnes. So they could be deployed to L1 with only a couple of heavy lift launches from Earth. Such sails should be able to transport well over 1500 tonnes to Mars orbit in less than a year if the delta-v requirements are limited to moving between Earth-Moon L1 and high Mars orbit (~1.64 km/s in total delta-v).
Comment by Marcel F. Williams — December 28, 2010 @ 9:53 pm
If the first small prospecting mission failed to find water in high concentrations, a repeat mission at a different location might cost only about $100 million. This is only about 1/10th of the overall budget. Given the different lines of evidence for hydrogen & water, I don’t think we are overpromising an in-space source of rocket fuel in adequate concentrations.
Although it seems a bit off topic, let me weigh in on the shielding issue. The strongest superconducting magnet produces a 45 Teska magnetic field. This is 900,000 times that of the Earth’s field. Might this be a solution?
Comment by JohnHunt — December 28, 2010 @ 10:06 pm
In 1985 there were 9 shuttle launches. With the most maintenance intensive part of the system gone (the orbiter) that flight rate should be maintainable using a side mount cargo version. With a J2 EDS, that is nine multi-ton lunar polar missions a year for approximately what the orbiter LEO missions cost. With later blocks using 5 segment SRB’s and possibly RS-68′s, the payloads increase.
I would imagine this is the program the U.S. should be funding under the guise of planetary protection- with support from the nuclear industry. The LFTR concept is a great fit for the moon, which is rich in thorium
deposits.
Send the robots to get a water refinery and base set up. Then send crews and tunneling machines for mining and building underground facilities. Finally, send the space ships and empty reactors to lunar orbit to get water for radiation shields and thorium fuel for reactors.
The nuclear pulse propulsion goes along with the planetary protection mission; those pulse units can be used to deflect impact threats as well as push a spaceship around.
This is doable with an HLV, but I cannot see it happening with only the inferior lift vehicles available if no HLV is quickly put into service. And Shannon’s sidemount is the only HLV design that can happen well inside of a decade. Indeed, money makes things happen quick, as proven by Apollo.
With true spaceships the one hundred or so other moons in this solar system can also be developed.
So in response to Dr. Spudis, I would say the “minimum spaceship” is not really very imaginative- just logical. And it is not a case of putting the cart before the horse, but rather building the cart and harnessing the horse. Thought “not likely for a variety of fiscal, legal and technical reasons”, the concept is simple and uses existing technology. Fiscally, the DOD has all the cash, legally, the lawyers can amend, and technically, it is the only available combination likely to be practical for a very long time to come.
Thank you for the opportunity to express my views.
Gary Church
Comment by GaryChurch — December 28, 2010 @ 10:22 pm
Gary,
Thought “not likely for a variety of fiscal, legal and technical reasons”, the concept is simple and uses existing technology.
Simple conceptually, but not practically. Orion-style atom bomb propulsion is not “existing technology.” There is also the little problem of expending a-bombs every time you want to go somewhere at several hundred million dollars per bomb.
Fiscally, the DOD has all the cash,
And they have plenty on their plate already to spend it on.
legally, the lawyers can amend,
You do have a rare sense of humor.
and technically, it is the only available combination likely to be practical for a very long time to come.
Hardly, but no matter — we’re not going anywhere in the next decade or so. So your paper rocket is just as good as anyone else’s
Comment by Paul D. Spudis — December 29, 2010 @ 8:37 am
“Rovers must be capable of surviving and functioning in extreme environments, including cold zones with temperatures as low as 25 K.”
This sounds like a formidable engineering challenge.
Comment by Hop David — December 29, 2010 @ 10:33 am
This sounds like a formidable engineering challenge.
It is, but we’ve designed equipment to survive extreme thermal environments in space before. It’s much less power intensive to keep warm in space than it is to keep cool — all of the equipment generates heat. Usually, we design to get rid of as much waste heat as possible. In this case, we seek to retain and use it. The most massive items on the rovers are the batteries, which must power the rover for hundreds of hours in deep cold and generate enough motor power to traverse steep slopes and negotiate 20 cm rocks. All doable, but as you put it, “challenging.”
Comment by Paul D. Spudis — December 29, 2010 @ 11:53 am
Orion-style atom bomb propulsion is not “existing technology.”
Nuclear weapons exist. Vast treasure was expended and is expended on black star wars devices like casaba howitzer that focus energy. So I must respectfully disagree with you Dr. Spudis. Creating a stream of plasma and directing it at a plate or other device is childs play compared to making something like VASMIR work. There is no other Hi Isp Hi thrust technology- nothing else will work. But I understand your reaction; you have to be a true believer like me I guess.
The DOD may have a plate full but it definitely needs to change it’s diet. Consider General Atomic, whose big DOD item is killer drones- they also make supercritical water oxidation units for life support systems. In my opinion those millions should be redirected. Along with many billions of other DOD dollars being spent on death machines.
Thanks for the rare humor compliment.
Comment by GaryChurch — December 29, 2010 @ 2:57 pm
@Hop David,
One more note to Paul’s response on the thermal challenge…. Our thought for the WIE rover (as point of departure now) and possibly for the EH rover is for an RTG or SRG or whatever it is now called (radioisotope decay devices for power generation). These have plenty of waste heat that can be used to keep sensitive parts warm. However, even with that, we recognize that there are challenges. Please refer to Table 4 in the back of the paper to see the list of what we consider to be the challenges that we know we will have to investigate should NASA adopt this or similar architecture. You will note that we already list challenges that deal with mechanisms and rotating machinery in an extreme environment.
Comment by Tony Lavoie — December 29, 2010 @ 5:34 pm
@Gary:
Why do you need high thrust?
Comment by Presley Cannady — December 29, 2010 @ 7:17 pm
At Johnhunt and Marcel;
I know you are a solar sail advocate Marcel- you are a true believer in that path. I am a nuclear pulse propulsion advocate. As I wrote previously, these two technologies do come together in the Medusa Concept. But otherwise they are pretty opposite approaches to propulsion. And the M2P2 plasma sail concept, which promised so much, still has application as a radiation shield. But the technology is not here and now like water and bombs. And the water is on the moon which is why I am posting here on Dr. Spudis site.
I understand solar sails are feasible but according to many people so are space elevators. While some people roll their eyes at atom bombs pushing space ships around I roll my eyes at space elevators.
on to John
No matter how much we dance around the subject addressing other radiation hazards, the heavy cosmic nuclei component of galactic cosmic radiation (GCR) still remains the show stopper for long duration human deep space missions. I find that people just seem to have an off switch concerning this inconvenient truth. State that the only solution guaranteed to work anytime soon for radiation is mass and distance on the order of over ten feet and hundreds of tons and the switch goes to off every time. No magnetic field scheme to stop this stuff, if even possible, is going to be any better than a massive water shield due to trade-offs concerning power generation, reliability, etc.
This is the same case with atomic bomb propulsion- try to keep a high power electric propulsion system using supercooled superconductors going for months and even years on end; compare that to lighting off bombs. KISS.
Regards, Gary Church
Comment by GaryChurch — December 29, 2010 @ 8:28 pm
Hi Drs Spudis & Lavoie,
Can you elaborate more about your cost calculations? Using figures that I know better (i.e. $/kg for Falcon 9 Heavies), I estimate that the mass equivalent could be lifted for about $4.5 billion. The development figure is harder to estimate. Even if each piece of equipment cost an average of $1 billion to develop, one would still be very far from $88 billion.
Also, could you make any comment about how much it might cost to scale up the production of producing fuel from lunar water ice. 150 metric tonnes might seem a small amount given the amount invested, but I would think that after the development is done, scaling up would be nowhere as costly.
Comment by JohnHunt — December 29, 2010 @ 11:21 pm
John,
Let’s see, we did not consider the price of a Falcon 9 Heavy, since it has not even flown yet. Should NASA adopt an architecture similar to ours, and the Falcon 9 Heavy becomes a proven option, i’m certain NASA would try to take advantage of it. All the better we say! That should reduce the cost of the robotic launches. What we used is the historical cost of launches (one for a simple mission and one for a complex mission from a LV perspective) and interpolated for both the Atlas 401 and 551. This is no slight on Delta’s part, because i did not have access to historical flight data. Again, at the time, assuming NASA would adopt this, NASA would try to get the best price from a reliable supplier. Hopefully, we have Over-estimated luanch costs.
Regarding the Development cost, our approach was to estimate the Mission cost (including NASA Project Management, SE&I, and Integration) in addition to the non-recurring engineering costs associated with a given development. One cannot use mass as the only variable in such an analysis to get a reasonable approximation of true cost. Most cost models have various knobs to turn, like complexity, percentage of new technology, number of interfaces, similarity to historical missions, etc. Also factored in is the second and subsequent unit cost, calculated by iteslf. Some of the costing of the components were derived from previous studies, and some were simply estimated compared to similar elements with like functions. Also factored in the cost is the NASA launch cost for the Moderately Heavy Lift, whereby we used methodology similar to what is now being planned for the new initiative on Heavy Lift defined in the 2011 Authorization Bill (signed in the fall sometime). As well, we estimated the Ops cost required to operate this architecture, including EVA development and training. Also factored in is Reserve, that pool of money that is estimated for that group of things that constitute “unknown-unknowns”. That covers mistakes, failures, and things that we really can’t predict but we know something will bite us in development, so we budget for it. All projects at NASA estimate this in a project’s budget submit. Finally, we estimated a rough cost/kg of water to be delivered by commercial entities to the LEO Fuel Station.
Concerning the cost of scaling up, yes, it would hopefully be a relatively flat cost vs production curve, but we did not hypothesize that far ahead; first it is important to start with something achievable, and nothing has yet been proven. We would like to see (assuming everything is what we think it is) the next phase develop a reusable water ferry from LLO to L1 should we put something there, to gradually start expanding the reach of the lunar products, but we haven’t run the numbers and i don’t know that we will yet. Best to wait until after the first 2 robotic missions play out and see where we are. We’d also like to examine use of lunar regolith for building materials, and in particular a habitation “dwelling” where the structure (again with the modularity concept) is produced on the lunar surface and the softgoods, avionics, and life support hardware is brought from the Earth, but we haven’t gotten far enough to examine its feasability.
And by the way, i am an engineer, not a scientist, so it is simply Mr Lavoie.
Comment by Tony Lavoie — December 30, 2010 @ 10:54 am
@Tony Lavoie and Dr. Spudis
Thanks for writing your excellent article on utilizing lunar polar resources.
Could you and Dr. Spudis elaborate a little more on the challenges of working in shadowed polar lunar environments. How would it be more difficult than having machines working during the 14 days of lunar night in other areas of the Moon?
Since it would probably take a rover less than a day (maybe less than a few hours) to travel out of the shadows to a sunlit area at the poles, it would seem like an easier environment to work in than at the lunar equator.
Comment by Marcel F. Williams — December 30, 2010 @ 11:38 am
Marcel,
The equatorial regions experience a wide temperature swing. The problem is not so much each extreme but the swing. Also, during the day (say, local noon), the sun is overhead in the equatorial region. Assuming that one would need radiator viewing deep space to dump waste heat, there is no easy way to do it at the equatorial region. If you point the radiator toward the horizon (unit normal is horizontal to the ground), the thermal IR of the regolith prevents efficient use of a radiator. Now flip 14 days at the equator and the hardware needs to be buttoned up tightly to prevent any heat loss. Well, if you do that, then during the equatorial day, you would fry the equipment, so a clever and complicated thermal control approach is required, with radiator sizing larger than theoretically necessary because of an inefficient view factor.
At the pole, the sun is never overhead but traverses the horizon, so firstly the radiator can look straight up (possible dust obscuration not withstanding). Secondly, it doesn’t get quite as hot, and if you have freedom to design a single face to the sun and just rotate as the days go by, it can be an easier design job. That being said, the Excavators/Haulers that we propose also need to go into craters which are REALLY cold (as low as 25-35K) and also be able to crawl back out and not overheat when they unload the ice ore. Still not easy, but we think managable. Note that the relaible long life of the Excavators/Haulers is in Table 4, one of our challenge areas.
In terms of how long a traverse takes, i’m still waiting for Paul (!) to provide respective distances between >80% solar illumination and 10% concentrations of ice! WE also don’t know for sure what the terrain is, but we can assume that the elevation will probably be significant, and this will slow the traverse significantly (incidentally, that is one reason why telerobotic presense is felt to be extremely helpful and valuable). Therefore, due to the mass and thermal time constant of the EH, it is not going to be the case of simply “running in and running out” of the Permanently Shadowed Region. We will have to assume that the EH comes to thermal equilibrium (or close to it) in the cold, and then again in the 80% illumination location. However, we can try to cold-bias the path and location where the EH empties its load and possibly recharges after it has completed a daily foray. All would be investigated should a similar architecture go forward and get approved by NASA. Hope that helps.
Comment by Tony Lavoie — December 30, 2010 @ 1:32 pm
In terms of how long a traverse takes, I’m still waiting for Paul (!) to provide respective distances between >80% solar illumination and 10% concentrations of ice!
You’ll have to continue to wait because we are still collecting (and analyzing) a wide variety of polar data from LRO! But that said, I can say with some confidence that we must be able to travel several kilometers (i.e., < 10) each way to and from a fixed lander based in the quasi-permanent sunlight. I can also say with some confidence that slopes will likely be on the order of 5-15 degrees (larger slopes occur but are rare); large blocks are avoidable and we can drive around them. Elevation changes will be on the order of hundreds (not thousands) of meters. Sunlight conditions for the rovers will be highly variable, but the Sun is always near (both above and below) the horizon. Thus, we must be prepared to provide our own illumination to drive and operate, if necessary. That’s why our rover instrument payload includes both visible and thermal IR cameras and imaging lidar (image creation by laser ranging).
Comment by Paul D. Spudis — December 30, 2010 @ 2:25 pm
There is no other Hi Isp Hi thrust technology-
“Why do you need high thrust?”
Presley, space travel is not only a distance problem, it is a time- distance problem. If you have a system that can reach a tremendous velocity but it takes decades to reach that velocity then it is of little practical use for human space flight.
In addition to this a hi thrust system allows the space ship to accelerate to cruising speed in a short period of operation and then shut down until needed again. Lower thrust systems must function continuously and flawlessly for months and even years. A few dud bombs in a pulse propulsion system would not doom the crew on a multi-year mission.
And finally, moving very large masses of over a thousand tons- as will be required due to the weight of radiation and zero G debilitation solutions, automatically presents a time-distance problem requiring relatively hi thrust.
Water and bombs are the only way to fly in deep space anytime soon (in my own humble, though well read opinion).
Water for shielding and life support and bombs for the high thrust and high isp required to get anywhere interesting within the few years that are the psychological limits of the crew.
The asteroid belt, which has Ceres and Vesta (Ceres has possibly more fresh water than earth), the moons of the outer planets- almost one hundred of a size suitable for human bases, are waiting. And our moon is where we can get the water to take the first steps. So exciting!
Comment by GaryChurch — December 30, 2010 @ 4:41 pm
Regarding questions about the operation of a rover at temperatures approaching absolute zero, a few observations:
(1) Both Soviet lunar rovers operated successfully on the lunar surface for periods of several months, enduring exposure to ~30 degree K nights with the aid of radioisotope heaters, like NASA’s MERs.
(2) Because the Moon has no atmosphere, there will be no convective heat loss. Conductive heat losses throught the wheels will probably not be very large. The most significant factor will be the loss of black body IR ratiation, which can be reduced by wrapping the rover in reflective foil. In a sense, the rover will be operating inside a thermos bottle.
(3) If properly designed, near-absolute temperatures can actually be benificial for some rover components, such as sensors (less thermal noise) and electronics. What tends to be harmful are the mechanical stresses resuling from cycyling the temperature of the rover several hundred degrees, many, many times… especially at mechanical interconnects such as electronic connectors.
Comment by Nelson Bridwell — December 30, 2010 @ 6:08 pm
Nelson,
Thanks for the good comments…
(1) yes, if we did not do RTG’s, i assume that NASA would use the radioisotope decay thermal devices to keep things warm. We thought that was getting into too much detail in the paper, but nonetheless that would be the strategy. I am surprized at the temps on the Soviet rovers. Our analysis shows that the regolith doesn’t seem to get that cold at night, but that is just my recolllection. It may be that an element on the the surface doesn’t get enough IR radiation to keep the temp from dropping so much when exposed to deep space.
(2) Correct. That is why the challenge is going to be more how to handle the hot case (where the sun is) when designing for the cold case.
(3) Precisely. The challenge is in the thermal swings, not the extremes in and of themselves. WE also need to be careful for CTE compatibilities (and incompatibilities) in our material selections. NASA has spent some technology money in the past on low temp sensors, and hopefully we would be able to take advantage of that work.
Happy New Year to all! Let’s hope that the decisionmakers think through the long term benefit and ramfications of the decisions that they make in 2011.
Comment by Tony Lavoie — December 31, 2010 @ 1:42 pm
“we’re not going anywhere in the next decade or so. So your paper rocket is just as good as anyone else’s”
That prediction has a very high probability of coming to pass Dr. Spudis. Very High. But…
No one predicted Saudi Wahabi Kamikaze’s bringing down those towers. And a black president?
I am a “gear geek”, so I like to imagine what can be done with the technology at hand or at least near at hand. Bush signed into law authorization to research small nukes- “bunker busters.” I do not know if the new treaty rescinds that authorization. If not, then then one of the legal issues to developing Nuclear Pulse Propulsion has been removed. There is in fact, a good chance that such devices, in the guise of fusion energy research or star wars, are available now. Much of the same physics concerning fusion apply to fission. Small, efficient, directed energy devices are the key to utilizing pulses of plasma in propulsion systems. Especially Medusa concepts that use a large woven alloy/carbon parachute to generate thrust.
What emerges, and as an engineer I am sure Tony is very interested in this, is a Jetson spaceship that folds up in a small package. In inflatable crew sphere full of water with an air filled inner sphere, a hard “bus” that holds the miniature thorium reactors, tethers, inertia reels and bombs, and the parachute.
Fill it up with moon water in Lunar orbit, deploy the chute and start lighting off bombs! The minimum spaceship. After cruising speed is attained, fold up the chute, start the reactor(s), and with the bus on one end of a tether and the water sphere on the other, spin up the artificial gravity.
Could such a space ship be carried into space on Sidemount vehicles within the decade? Possibly. Two key points are the Launch Abort System (LAS) developed for Ares and the hundreds of tons of water from the moon. The LAS and human-rated sidemount hardware can safely transport the fissionables into space. The moon can provide the water for the radiation shield and much later the thorium reactor fuel. And perhaps down the road even the bombs.
I imagine the only possible scenario in which this might happen would be a near miss by an asteroid or comet. A very near miss. In that case a new space race might develop. Do we need the moon for these first planetary defense space ships? Perhaps the first ship might have a multi-ton plastic crew compartment but this would provide inferior shielding and life support and lofting this much shielding, even as a kind of wet workshop, using the plastic as staging, would be prohibitive.
So it could happen and Dr. Spudis’ prediction would prove false. I am not sure if want this scenario to come about or not. It reminds one of the old adage, “be careful what you wish for.”
The water is critical. The moon and it’s resources are the key to opening the solar system to exploration- and defending the earth from impacts.
Happy new year
Comment by GaryChurch — December 31, 2010 @ 5:13 pm
Gary:
What people overlook is that although nuclear pulse detonation propulsion of humans is very problematic for a number of reasons (high-g acceleration, radiation sickness, molecular integrity of the spaceship structures after intense bombardment by neutrons and gamma rays…)
it is precisely those limitations that would make nuclear pulse detonation the ideal method for deflecting massive NEOs where we do not have decades of advanced warning.
So this technology will be with us in the not-so-distant future, but perhaps not employed exactly the way that you anticipate.
But let us not stray to far afrield from the Moon, the focus of Paul’s provacative and worthwhile essays.
Cheers,
Nelson
Comment by Nelson Bridwell — January 2, 2011 @ 3:25 pm
“But let us not stray to far afrield from the Moon”
Let us not stray from the facts Nelson. The “high-G acceleration” of a nuclear pulse propulsion system is why there is shock absorbing system that brings the forces down to 2 to 4 G’s. Radiation sickness is a problem in the original design mainly due to secondary radiation from the atmospheric launch phase. As for the “intense bombardment”, the pulse propellent soaks up the majority of the radiation as it is converted into plasma some distance from the engine. Most the possible problems are found in a ground launch vehicle. There will be no ground launched NPP. It will be a deep space system. Please do not confuse these two different designs.
In a deep space system the distance between the vehicle and the pulse is much farther away, decreasing the radiation by an order of magnitude. And since the purpose of using the system is to push a massive water shield around, the radiation is the least problem. The shock absorbing system can also be engineered to stroke several times farther in a space system.
I suggest you read some of the sources available and get back to me. The popular bible for NPP is “Project Orion” by George Dyson, and Dr. Paul Bonometti has also published several papers on NPP. There are also old PDF’s with NASA summaries and work done by Solem on the Medusa concept.
I also do not understand your comment “-those limitations that would make nuclear pulse detonation the ideal method-”.
Please cite your sources Nelson. Thanks.
As for straying- I am talking about the water on the moon as a prerequisite to any deep space human missions due to the need for a practical radiation shield. The mass of this shield makes Nuclear Pulse Propulsion the only “off the shelf technology” available to propel such a massive spaceship.
Plastic shielding like RFX1 would also provide the right hydrogen rich shielding but is not practical to lift in the hundreds of tons necessary for full protection from the heavy nuclei in GCR.
So the water on the moon is where it all must start. I am not straying.
Cheers.
Comment by Gary Church — January 3, 2011 @ 3:41 pm
Correction: Dr. Joe Bonometti. Apologies Joe.
Mr. Lavoie might be interested in his You Tube presentation on Liquid Fluoride Thorium Reactor from 2008. Extremely interesting and there is mention of the Thorium deposits on the moon. The LFTR concept as explained requires gravity to be fail safe but artificial gravity would suffice and the beauty of LFTR is that it can be shut down and started back up far more easily than than a conventional uranium pellet reactor. Dr. Bonometti is the only current authority on Nuclear Pulse that I have corresponded with.
While Helium 3 on the moon is considered a farce by many, Thorium is no joke. It is easy to detect, easier to refine than uranium, and after water, may be the second most valuable lunar resource.
Comment by GaryChurch — January 3, 2011 @ 8:02 pm
Gary,
We should always encourage new thinking with innovative solutions. I personally have little data on the technical engineering for nuclear pulse propulsion, although as a good engineer i am naturally curious. Using lunar Thorium is also an interesting discussion. At some point on a similar note, if NASA ever decided to adopt an architecture similar to the one we outlined, one of the trades that should be done is the cost-effectiveness of a small nuclear reactor in lieu of the multiple solar arrays. Like the launch vehicle selection, i don’t think we care as long as we get power to the loads that we have for a certain cost that we have budgeted. Our gut feel (or at least mine) is that SA’s that fly with the payloads are cheap and we don’t have to worry about robotic cabling from a common power source, but someone should look to see if that intuition is valid.
I assume that you have written or will write about your ideas for nuclear pulse propulsion or even thorium reactors in more detail so that you can benefit from a more detailed review.
Relative to this posting, it might be more beneficial to engage the conversation back a little toward what Paul identified at the start, that being the affordability of the space program for returning to the Moon; that includes a critique of our architectural approach or even our rationale for why this is a good idea. thanks,
tony
Comment by Tony Lavoie — January 4, 2011 @ 6:35 pm
Thank you for the reply Mr. Lavoie, I will try and step back toward the architecture being discussed. Being on fire for a certain approach can be a handicap.
Regards, Gary Church
Comment by GaryChurch — January 5, 2011 @ 3:14 pm
I really do not want to be stereotyped as a nuke nut. In fact, I am not an advocate of nuclear power on earth; I am against commercial nuclear power and favor covering the deserts in solar energy farms to meet the planet’s needs. That said, I find it interesting that nuclear weapons perhaps have actually prevented major conflicts between the superpowers- though doing so through the threat of mutually assured destruction is the prime example of an extreme solution. I also find it interesting that “fast fission” and fusion devices hold the most immediate solution to solving the problem of human spaceflight. Unfortunately there is so much resistance to nuclear technology being used in space it is hard to get a couple pounds of plutonium up due to protests, as in the case of Cassini. Nuclear energy to the space age is like steam was to the industrial age; we must use it to advance.
Don’t worry, this is leading up to something, stay with me.
On the matter of constructing a lunar base- I would propose sending a drilling rig in pieces to be set up robotically, digging a hole a couple thousand feet down, and exploding an H-bomb to create a sports arena sized cavern. H-bombs are actually fairly clean and without the need to weaponize, an even cleaner explosive device could be built. Wait a couple months and then open it up and robotically remove the radio-active debri and presto- home sweet home. Then just pour the water down the hole to partially fill up the cavern, use a focusing mirror to shine a sunbeam down the shaft onto the lake, and habitat created.
I suspect that the lesser gravity will be a problem though; I am of the opinion that 1G is required to maintain health. On lesser gravity bodies this may be the obstacle to long duration tours for humans. My best idea to solve this is to bore a circular tunnel a couple thousand feet in diameter and have a train speeding through it to generate gravity for crew quarters- sleeper cabins and gyms. So to go to work the crew members would jump off the train and then do their shift and recreate and then return for exercise and sleep to prevent lo-G debilitation. I like this idea because it will also work on any asteroid or comet more than a few miles in diameter- of which there are plenty of course. So I am of the humble opinion that tunneling machines should be a priority versus building on the surface. There may possible be some natural lava tube systems that offer subsurface habitation out of the radiation. Is there earth penetrating (moon penetrating) radar capable of finding these formations?
I hope this may generate some new ideas for you, Dr. Spudis and Mr. Lavoie.
Regards, Gary Church
Comment by GaryChurch — January 5, 2011 @ 5:31 pm
“I assume that you have written or will write about your ideas for nuclear pulse propulsion or even thorium reactors in more detail so that you can benefit from a more detailed review.”
I have posted alot on Space Politics and The Space Review but am now banned from those sites for getting upset at being called an idiot and a moron. Returning such compliments does not work with good ole boy clubs it seems. Dr. Spudis spouse manages to post there without getting upset but I do not know how she does it. I am currently an “older student” in an art college learning to be an industrial designer. Concepts like Bernal Spheres when applied to the 70,000 icy bodies in the Kuiper belt fascinate me. I was born to “think outside the box” and perfectly good ideas like NPP also naturally excite me.
I have no education in higher mathematics so my speculations are not worth much review I am afraid. But after troubleshooting autopilots for so many years I think I have a feel for what does what. I want to see the U.S. back in space and in deep space on journeys to the outer planets- and beyond. Posting on blogs is so far the only way I have to contribute.
Thanks for your time Mr. Lavoie
Regards, Gary Church
Comment by GaryChurch — January 6, 2011 @ 12:24 am
[...] a lunar geologist, has suggested a plan to return to the Moon, which features, among other things, robotic resource extraction and the deployment of space-based fuel depots using lunar water even before the first human [...]
Pingback by The Prospects For Lunar Mining | JetLib News — January 17, 2011 @ 7:27 pm
[...] a lunar geologist, has suggested a plan to return to the Moon, which features, among other things, robotic resource extraction and the deployment of space-based fuel depots using lunar water even before the first human [...]
Pingback by Android OS news » The Prospects For Lunar Mining — January 17, 2011 @ 10:31 pm
Dr. Spudis and Mr. Lavoie,
Please correct me if I’m mistaken, but there might be applications on Earth for the robotic prospectors and construction gear you describe.
I’d be very surprised if energy companies were unwilling to use the robotic prospectors to explore Siberia, Alaska, or the Canadian tundra for oil and natural gas. In the same manner, exploration of Antarctica would become less dangerous to humans if the prospector/searcher robot were used. For that matter, vulcanologists may use them to gather data about active volcanic events.
Assuming the prospector finds oil, the excavator/hauler rover robot could be useful in remote locations as well. Setting up a base camp for human geologists to use while they evaluate the site might be much easier if the camp’s foundations were already in place. Alternatively, digging to a particular depth could take place around the clock, getting the scientists there faster. For that matter, the excavator may be able to play a role in mine rescue operations, tirelessly digging away until a rescue tunnel is complete.
Returning to the active volcano scenario, the excavator could dig new channels that guide lava and pyroclastic flows away from humans. In some cases (Montserrat, Hawaii) it might even be possible to direct the flow out to sea to generate more land area.
I’ve ignored defense applications of both the prospector and the excavator/hauler, but I can imagine several uses in that arena as well. Using a prospector as a demining platform is an obvious choice. Using an excavator to set up a temporary base camp is another. (The base camp wouldn’t get a Human Habitat, but air-dropping several prefabricated shelters made from converted cargo containers should be possible.)
I concede that none of these scenarios have direct applications to your proposed trip back to the moon, but there are several benefits:
1. Lower cost of manufacturing since many more are being constructed
2. Gain valuable information about how the robots work while we can still get to them easily
3. Create control systems and software for robots based on moon
4. Experiments in hostile environments have applications in space, particularly exploring volcanos above Arctic Circle (rapid temperature swings)
Anyway, just wanted to get your opinion.
Thanks!
Comment by mbear — January 18, 2011 @ 3:22 pm
Robots and robotic telepresence is already used on Earth in a wide variety of applications — one of the most notable recent uses was the capping of the BP oil well in the Gulf of Mexico last year. The Canadians are using robotic equipment in nickel mines in Sudbury (which coincidentally happens to be an ancient impact basin). So our proposed technology is just a minor extension of technology already used for purposes similar to what we envision.
Comment by Paul D. Spudis — January 18, 2011 @ 3:44 pm
[...] This post was mentioned on Twitter by Stafford Masie, pavlos stefanos. pavlos stefanos said: Can we afford to return to the Moon? http://t.co/HpUUYPE via @AirSpaceMag [...]
Pingback by Tweets that mention Can we afford to return to the Moon? | The Once and Future Moon -- Topsy.com — January 19, 2011 @ 5:14 am
I’m not a big fan of robotics (even though I’m an automatic control systems engineer) or expendable HLVs, but I’ll wait until I’ve read your “…Affordable Lunar Return” paper before I comment on it. In the meantime, I refer to my posts on your “NASA Lost It’s Way” post – #42 and on – for my approach to an affordable lunar/Mars program. I also just ordered a copy of your new book, and am anxious to see some of my posts in print.
Comment by Dick Morris — January 20, 2011 @ 11:29 pm
Definitely it is a good idea to develop a Plan as a for-profit long-term enterprise.
This idea is consistent with a potentially lucrative medium-term commercial project of “remote lunar tourism”.
Really, perhaps the only lunar resource that is inaccessible on Earth and is able now to attract considerable interest of a great number of people, this is unique cosmic landscapes and views of that really extraterrestrial world. But while even a simple flyby around the Moon remains too expensive, real lunar tourism remains beyond the horizon.
The remote lunar tourism with the rovers, that moves on the moon surface(like “Lunokhod” or up-to-date rovers from the teams of Google Lunar X PRIZE ), combined with “on-Earth” real time “rover simulators”, gives us a chance to get all (or nearly all) the thrill of lunar tourism in the not-so-distant future. Rovers are equipped with 3-D cameras and sensors. Ground-based simulators reproduce all the movements of the rovers and the 3-D views. So, tourists in these “bus-simulator” get all the sensations (except for low gravity), the same as if they were traveling on the lunar surface.
Little bit about the commercial features of the project.
Assuming that the lunar rover keep functionality over 10 lunar days (as it was for “Lunokhod-1”), total time of useful operation of such complex will account for about 3000 hours. Number of participants of one tour, which is determined by the capacity of “bus-simulator”, may be from 20 to 30 persons. Simulators are located in different time zones with an interval of 4 – 6 hours to ensure continuous operation with a lunar rover for a lunar day. For the duration of the tour for about 1 hour for 3000 business hours of a complex from 60 to 90 thousand persons can become participants of tours.
Payload delivered by “Proton” carrier to the surface of the Moon in missions “Luna-17”, “Luna-21” ( “Lunokhod-1,-2”) was about 800 kg. Mass of modern lunar rovers will be 50 - 80 kg, and carrier in a similar configuration can deliver for one launch 10 lunar rovers on the surface of the Moon. Thus, the total number of operating systems will be 10, and the total number of participants of lunar tours can be from 600 to 900 thousand persons over the time of active operation of rovers.
Ticket price for a 1-hour tour at $1000 seems real (compare with the price of $200,000 for 10-minute suborbital flight) and, thus, the total revenue during the operation of vehicles will range from $600M to $900M.
We can also consider the possibility of lease rover + “bus-simulator” for family tours and other options.
Preliminary calculations give us a project costs not exceeding $500M, so we can expect to gain from $100M to $400M from this project.
Of course, the rovers can carry some scientific instruments and perform drive-by measurements.
Comment by Victor Serge — January 22, 2011 @ 5:54 am
While it may take 5 meters of water to stop all cosmic rays, and secondaries, we don’t have to do that. The GCR flux is too small to cause any acute effects – it’s more of a career limiting factor. Airline pilots receive a significant radiation dose from cosmic rays over the course of a career, but we don’t shut down the airlines because of it. For that matter, the people in Denver receive a greater dose than people who live in Seattle, but we don’t evacuate Denver.
Zubrin has calculated that the crew of one of his Mars Direct round trip flights would receive a total dose from
GCRs and SPEs of approx. 50 REMs. That’s not even enough to cause radiation sickness even if received all at once. That assumes a reasonably well shielded “storm shelter”, with the shielding consisting largely of existing life support consumables. So we don’t need hundreds of tons of shielding mass.
Comment by Dick Morris — January 24, 2011 @ 10:07 pm
I absolutely agree that setting up a propellant plant on the Moon must be the first order of business for a lunar base program if it is to be affordable. Some authors have assumed that such an “advanced” capability would not be established – probably for some decades – until the traffic built up enough to “justify” the cost. The problem with that approach is that the traffic never builds up because each flight costs so much, and all the money will have to come from the public treasury. The ability to refuel spacecraft on the Moon will not only substantially reduce the amount of mass that needs to be launched from Earth, it will allow us to develop a fully-reusable transportation system between LEO and the lunar surface. Those two factors will enable a substantial reduction in the cost of each flight, and it is only a major reduction in the cost per flight which will enable the flight rate to build up for such profitable applications as exporting LOX, or other lunar produced material to cis-lunar space, and, eventually, for lunar tourism.
And it would be quite beneficial if such a capability was available from the beginning of manned operations in order to reduce crew rotation costs. For the foreseeable future we will need to establish a reasonable limit – months rather than years – on the duration of tours of duty at the base, and heavy costs for crew rotation could jeopardize the sustainability of the project. Relatively short tours will be necessary until such time that we establish that humans can live permanently in 1/6th gravity so crews can live on the Moon for long periods, and even bring their families, which will be the beginning of the colonization of the Moon. I believe that that will happen, though it is not yet certain.
The first problem I see is that the establishment of a completely new industrial process in a (very) remote location where nobody has ever been, in a relatively hostile environment which cannot be completely simulated on Earth, entirely with tele-operated robots will be very challenging to put it mildly. I won’t say that it’s impossible, but it will probably be right at the limit of feasibility. And for all of that machinery to operate reliably untended for up to 10 years on the Moon without a major breakdown, or other unforeseen problem, would seem to require a bit of luck. We could get lucky, but unforeseen problems are quite likely I should think. Unforeseen problems would not necessarily be insurmountable with robots, but for flexibility and adaptability, robots cannot, and may never approach human beings.
A second problem concerns the form in which the ice deposits now known to exist at the poles will be found. I think it highly unlikely that we will find anything resembling snow drifts on the Moon which can simply be scooped up and hauled away. I think it is almost certain that the ice deposits originated through a process of vapor deposition, much like the way we aluminize telescope mirrors. Water vapor in the Moon’s extremely tenuous “atmosphere”, due to outgassing or cometary impacts, will migrate to the permanently shadowed areas near the poles and freeze out on the surface in a continuous layer. Over the eons relatively thick layers could be built up.
At the temperatures found in those permanently shadowed areas, ice would be about as hard as granite, and would require hard-rock mining techniques to acquire. Drilling and blasting on the Moon would present some interesting problems; jack-hammers are another possibility. Either way, I don’t think that unmanned payloads of the relatively small size that you are proposing would be up to the task. You do leave open the possibility of combining two or more of your payloads into one and launching it on an HLV. That is the approach that I would follow, except that it would make sense to precede those flights with a couple of smaller, unmanned flights to each pole, as you propose, to characterize the ice deposits and then explore potential base sites. Then we could send the first 4 or 5 element of the initial base to the selected site, to include a hab. module, a solar/nuclear power supply, the propellant manufacturing pilot plant in one or two large packages, and a fairly large, tracked rover, with a pressurized crew cabin consisting of a cylinder about 8′ dia. by 15′ long, over a period of about a year. The rover would have excavating and other construction capabilities, and be able to climb and descend fairly steep slopes.
At that point we would be ready to send the first crew, who would spend several weeks to several months emplacing, integrating, and checking out all the hardware. The propellant plant would then be fully operational and subsequent crews could avail themselves of lunar produced propellants for their return flight. I suggest that it would make sense for that first crewed flight to employ transportation system elements developed for Zubrin’s Mars Direct architecture. The earlier unmanned flights would also use some of those same elements, except for the Earth-return vehicle. Once the base is in full operation and the Mars launch window opens the launch crews on Earth can send the first two Mars Direct payloads on their way. We can then resume lunar operations. Mars launch windows are about 2.2 years apart, and we have to keep the launch and engineering support staffs on the payroll whether they are flying anything or not, so doing the programs in parallel will save a major amount of money.
Finally, I wonder if the poles are really the best sites for an initial lunar base given the difficulties and uncertainties involved. I’m sure that we will get around to making use of the water resources at the poles eventually, but, since the typical LOX/LH2 propellant combination is about 86% LOX, it is liquid oxygen which is the key to an affordable lunar base program. The ability to refuel with liquid oxygen alone makes possible the development of a fully-reusable transportation system between LEO and the surface of the Moon, and we can manufacture liquid oxygen anywhere on the Moon since lunar regolith is approx. 40% oxygen. Literally dozens of different processes for producing oxygen from regolith have been proposed. Some of those processes involve the reduction of lunar ilmenite, such as carbo-chlorination followed by magnesium reduction, which would produce titanium ferride as a by-product. Tanks of powdered TiFe could hold as much hydrogen – for a regenerative fuel cell system – in the form of a hydride as the tanks could hold in the liquid form, without the complication of deep cryogenic temperatures. Such a system could provide a considerable amount of night-time power for a base at a non-polar site.
Once the propellant plant is in full operation, we will be able to turn our attention to other applications, such as lunar science, so if would be wise to locate the base at a site which supports such activities. While there is probably no site on the Moon which is completely devoid of scientific interest, those sites seem to be concentrated in the lower latitudes in and around the mare. A few months ago I re-read your classic paper in the 1985 “Lunar Bases…….” volume. You begin your proposed long-range traverse in the crater Murchison, and it seems to me that the Sinus Medii area would be an excellent site for an initial lunar base. I propose a site on the dark mantle mare between the craters Triesnecker and Ukert (see AS10-32-4819; NASA SP-246 p. 70). I have seen few areas on the Moon with such a wealth of interesting geological features, including a wide variety of craters of different sizes and ages, and all kinds of rilles, including some sinuous rilles which may be associated with lava tubes. Also nearby is Rima Huyginus, one of the most interesting sites on all the Moon, which has been suspected as a site of outgassing. The discovery of an active vent could provide a useful source of volatiles, including carbon and nitrogen containing compounds which would have a wide variety of uses including life support and propellants. Also nearby is a rather large “gash” radial to the Imbrium basin running just southwest of Ukert, which is elongated in the same direction.
Well, I see that my IV is done, so I will shut down and be on my way. Back with more later.
Comment by Dick Morris — January 26, 2011 @ 8:10 pm
Dick,
A few comments on your remarks.
The first problem I see is that the establishment of a completely new industrial process in a (very) remote location where nobody has ever been, in a relatively hostile environment which cannot be completely simulated on Earth, entirely with tele-operated robots will be very challenging to put it mildly
This is largely a matter of perception and opinion. First, it is NOT a “completely new process” — we’ve been extracting water via evaporation for centuries. The polar regions are not particularly “hostile” as an environment — the sunlit areas are quite benign, with near constant, moderate temperatures, while the cold traps are completely predictable. I agree that teleoperations are the big issue but even there, it is the coordination and systems integration knowledge that is needed, as each individual action the robots will perform has already been done repeatedly on Earth.
I think it highly unlikely that we will find anything resembling snow drifts on the Moon which can simply be scooped up and hauled away. … At the temperatures found in those permanently shadowed areas, ice would be about as hard as granite, and would require hard-rock mining techniques to acquire.
This is unlikely and in fact, we have some (indirect) evidence that the lunar polar ice is NOT “hard as granite.” The water is indeed vapor-deposited, but it is a stochastic, not continuous, process. Thus, during short intervals, we may accumulate large amounts of water, followed by long periods of quiescence. The cold traps have been cold for billions of years and this ice has never experienced freeze-thaw. It is the freeze-thaw cycle which induces re-crystallization and makes “rock ice.” Regolith processes produce “fairy castle” structure, meaning that we have an aggregate of ice and soil which contains much void space. In fact, the low radar backscatter of the non-shadowed areas near the high backscatter ice deposits are indirect proof of a particulate, “fluffy” structure — if the “granite-like” deposits you envision existed, we would see strewn blocks of impact-excavated ice, causing higher backscatter. The absence of same suggests that rock-like ice deposits do not occur. Having said that, I agree that we need to characterize the deposits and that’s why our architecture leads with prospecting rover missions at both poles.
I wonder if the poles are really the best sites for an initial lunar base given the difficulties and uncertainties involved.
The uncertainties of lunar base construction aren’t any fewer for non-polar sites. While it’s true that oxygen is the majority of the mass in propellant systems, we want the water and other polar volatiles for other purposes as well. The poles have near-constant sunlight, a benign thermal environment, and the rare (on the Moon) volatiles — including nitrogen and simple organic molecules — that make its habitation possible.
We go to the poles according to the Willie Sutton principle: it’s where the money is.
Comment by Paul D. Spudis — January 27, 2011 @ 3:45 am
Oops! In the last paragraph change “mare” to “maria”. My doctor’s office was about to close so I didn’t have time to do a proper proof-read.
I’m in favor of whatever works, so if the initial robotic explorers find large deposits of ice in an easily recoverable form then we can plan on a polar base. But we’re not going to want just one base on the Moon, and a low latitude base would be better for science. It also immediately solves the communication problem, and has logistical advantages. Before long we’re going to want to put a propellant depot in LLO and that would have to be a polar orbit for a polar base, so launch windows, going and coming, would be less frequent. Once we have a propellant depot in LEO, launch windows to the Moon will be a function of the precesion of it’s orbit, and there is no guarantee that the LLO plane will be conveniently oriented when we get there. Some fairly large plane changes may be required at one end or the other. (BTW I took two quarters of celestial mechanics at the UW.)
I also have a concern about the long time delay between the beginning of robotic operations and the first human landing. I would hope that we could come up with a program leading to the first human landing “before this decade is out”. I see that ESA is planning a robotic lander and rover to be landed near the south pole. I assume that it is intended to characterize the ice deposits. One way or another we should know enough about those ice deposits before the end of this decade to permit a decision on where to locate an initial base. The first human landing could then be directed to that site shortly thereafter.
Comment by Dick Morris — January 27, 2011 @ 2:44 pm
I don’t mean to say that the “new industrial process” will require all new technology, just that it is a novel application of existing technologies (and exactly which technologies will be required remains to be seen). I have not studied the matter, but it is my impression that it is the temperature which makes solid ice hard as rock not the exact crystal structure, and it is difficult to see how vapor deposition could produce anything other than solid ice, regardless of the rate of deposition.
This discussion has reminded me of a speaker at the Space Development Conference in San Fransisco many years ago who remarked that if one wants to travel north from San Fransico one could swim, or hire a boat, but a sane individual is certain to employ another alternative: the Golden Gate Bridge. The Moon and it’s resources are like the Golden Gate Bridge: They are an “insurmountable opportunity”.
Indeed there will eventually be a lot of money in lunar resources, including water, but there could be almost as much money in lunar LOX as in water, since the typical LOX/LH2 propellant combination is approx. 86% LOX. Solar wind implanted hydrogen may be sufficient for many applications.
Lunar water is not essential for a lunar base program to be affordable – lunar LOX will do quite nicely – so the question of where to put an initial lunar base remains open, in my opinion. We should focus our efforts on getting the program started, ASAP, and decide where to put it when we have more information.
Comment by Dick Morris — January 27, 2011 @ 3:31 pm
Lunar water is not essential for a lunar base program to be affordable
Well, we differ. Yes, one can extract oxygen from regolith — through a variety of energy-intensive, low-efficiency processes. To crack oxygen from the metal oxides of the regolith using industrial reduction processes at the equator, you need almost two orders of magnitude more energy than harvesting water ice near the poles. Plus you have to survive the 14-days of night time at the equator. The near-permanent sunlight and water ice near the poles makes ISRU easier and hence, affordable.
Comment by Paul D. Spudis — January 28, 2011 @ 4:38 am
Two orders of magnitude seems a bit much. Do you have a reference you could point me to? Night-time power at an equatorial site could be supplied by an SP-100 type reactor or a regenerative fuel cell system. (I think your estimate of “several tens of billions” to develop such a reactor system may be off by about two orders of magnitude.)
Comment by Dick Morris — January 28, 2011 @ 8:20 pm
Dick,
Do you have a reference you could point me to?
You can start by looking at the papers in these two volumes:
http://ads.harvard.edu/books/lbsa/
http://www.nss.org/settlement/spaceresources/library.htm#SP509
All of the oxygen production methods studied before the discovery of lunar polar ice require enormous amounts of energy (to break the metal-oxygen bonds in lunar soils) and are low-yield processes (meaning that you waste a lot of that energy.)
Night-time power at an equatorial site could be supplied by an SP-100 type reactor or a regenerative fuel cell system. (I think your estimate of “several tens of billions” to develop such a reactor system may be off by about two orders of magnitude)
Think what you please. But the SP-100 nuclear reactor does not exist and the last time the government tried to build one (early 1990′s), we spent over $10 billion and got absolutely nothing to show for it.
Comment by Paul D. Spudis — January 29, 2011 @ 4:17 am
According to this, http://www.nuclearspace.com/Prometheus_PEIS_FirstStep.html, the SP-100 program spent over $400 million in 1980 dollars, and that was over a period of about 7 years, so the design should be considered mature. It should not require a great deal of effort or expense to resurrect the design and bring it to flight status.
I took a few years of chemistry and physics in getting my BSEE, so I am familiar with the energies involved. Reducing metal oxides requires a lot of energy, but then the hydrogen/oxygen bond contains a lot of energy too, which is one reason it makes such a good propellant combination.
Comment by Dick Morris — January 29, 2011 @ 7:58 pm
You’re still missing the point. My topic is “affordable” lunar return. By avoiding the equator as a site, we avoid the requirement for nuclear power in the early stages of deployment. By avoiding nuclear power, we avoid its costs, which not only include the cost of building the reactor, but the enormous bureaucratic and legal overhead that must be paid before one can even launch a nuclear-powered space mission. All this effort to use the lowest-grade feedstock on the Moon, when very high grade water ice is available at the poles.
I appreciate that you have a different view. I’ve let you express it here. Now we move on.
Comment by Paul D. Spudis — January 30, 2011 @ 4:49 am
Affordability is the main issue that I have addressed on the internet for the last 9 or 10 years. That issue mainly revolves around logistics, and the cost of Earth-to-orbit launch is the biggest single driver for the cost of everything we do in space. The relative costs of specific technology alternatives, such as nuclear vs. solar power supply, is a relatively minor issue compared to the relative costs of expendable vs. reusable launch and in-space transportation systems. We have had the technology to build reliable, fully reusable space transportation systems for over 40 years, and it seems to me that such systems are long overdue.
Lunar ilmenite is one of the most often proposed feedstocks for LOX production, and ilmenite is not difficult to separate from regolith by magnetic means, so the input to the chemical plant would be high-grade. The processes also produce titanium and/or iron for construction as a by-product. That’s the reason I have tended to favor a high-Ti mare site.
However, I am certainly not opposed to building a base at a polar site (and I assume that you are not opposed to building a base in the equatorial zone for scientific purposes as a follow-on). But whether we can really call the polar ice “high-grade” remains to be seen. It could well contain substantial quantities of impurities such as methane, ammonia, CO2, etc., though those substances would also be quite useful once they are separated and purified.
We need nuclear power for propellant production on Mars, so it’s not like we can avoid using it entirely.
Comment by Dick Morris — January 30, 2011 @ 7:59 pm
Lunar ilmenite is one of the most often proposed feedstocks for LOX production, and ilmenite is not difficult to separate from regolith by magnetic means, so the input to the chemical plant would be high-grade.
No, it is not easy to separate — agglutinate regolith glass is also magnetic and it may or may not contain much titanium. Moreover, ilmenite reduction is very low efficiency, with typical yields on the order of a few percent, even with pure ilmenite feedstock.
We need nuclear power for propellant production on Mars, so it’s not like we can avoid using it entirely.
That requirement is far into the future, after we have established a foothold on the Moon.
Comment by Paul D. Spudis — January 31, 2011 @ 3:54 am
“No, it is not easy to separate — agglutinate regolith glass is also magnetic and it may or may not contain much titanium. Moreover, ilmenite reduction is very low efficiency, with typical yields on the order of a few percent, even with pure ilmenite feedstock.”
Again, do you have any specific references, preferably online not a book list?
There is probably nothing we will be doing on the Moon for the foreseeable future that will be truly “easy”. What I mean to say is that the technology exists and is not terribly complex. Agglutinates, and other large fragments, can be removed by sieving the regolith prior to feeding it into the separator. Ilmenite is a major raw material for titanium and TiO2 production, and I would not expect a process that is only a few percent efficient to be economically viable. How exactly do you define efficiency in this case?
“We need nuclear power for propellant production on Mars, so it’s not like we can avoid using it entirely.”
“That requirement is far into the future, after we have established a foothold on the Moon.”
Not necessarily. I agree with Dr. Zubrin that a lunar base is not essential for going to Mars, and we could have been on Mars about 7 or 8 years ago had NASA gotten behind his Mars Direct proposal. I suggest you look at his articles in the Feb. 21, 28, and March 7, 2005 Space News, “How to Build a Lunar Base”, for an updated description of the plan.
While we don’t absolutely need to go back to the Moon before going to Mars, we do need to do a fairly extensive flight test program first, and we might as well make use of that opportunity to land the first elements of a lunar base on the Moon, as I mentioned previously. Once the first Mars flight is on it’s way we can return our attention to the Moon for over 2 years until the next Mars launch window.
I find it a little ironic that I, an engineer, am anxious to go back to the Moon, initially at least, for science, while you, a leading lunar scientist, want to go back largely for commercial/engineering reasons. When do you envision building a base in the equatorial region for scientific exploration?
Comment by Dick Morris — February 2, 2011 @ 10:19 pm
Agglutinates, and other large fragments, can be removed by sieving the regolith prior to feeding it into the separator.
No. Agglutinates have the same size ranges as all other regolith particles, including ilmenite grains. By low efficiency, I mean a couple percent mass of product made per unit mass of feedstock collected.
Not necessarily. I agree with Dr. Zubrin that a lunar base is not essential for going to Mars,
My end point is not Mars, but rather, an extensible system of space transportation. We go to the Moon to open up first cislunar, then interplanetary space. Mars will come when we have established footholds in these spheres.
When do you envision building a base in the equatorial region for scientific exploration?
I can do almost all the science at the poles that I would do at the equator. If we can re-fuel at the lunar outpost, the entire globe is opened up for short sortie missions staged from the Moon, not the Earth.
Comment by Paul D. Spudis — February 3, 2011 @ 4:31 am
The efficiency of oxygen recovery from ilmenite via hydrogen reduction may be only a few percent in one pass through the reactor, since the reaction is reversible, but if the water vapor is continuously removed, with the unreacted hydrogen recycled along with hydrogen from the electrolyzer, then all the FeO can be reduced. The iron can then be sparated from the TiO2 via the Mond process. The TiO2 can be reduced to recover the remaining oxygen by carbo-chlorination, or other reactions. The ilmenite can also be carbo-chlorinated directly to recover all the oxygen.
Comment by Dick Morris — February 22, 2011 @ 7:20 pm
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