Date: October 20, 2011

Title: Plan for a Sustainable Lunar Base

Podcaster: Nancy Atkinson with Dr. Paul Spudis

Links: NASA Lunar Science Institute, Paul Spudis’ website, Spudis Lunar Resources

Music: “Amelia” by Ben Bedford from his “Land of the Shadows” CD.

Description: Many have dreamed of a human settlement on the Moon but will it ever become a reality? Dr. Paul Spudis has been studying the Moon for over 30 years and has long been an advocate of having people return to the Moon to live and work there. He and a colleague, Tony Lavoie, have come up with a plan for setting up a lunar settlement, and this is a unique system that not only creates a Moon base, but also a type of transcontinental railroad in space which opens up cislunar space – the area between Earth and the Moon – for development.

Bio: NLSI brings together leading lunar scientists from around the world to further NASA lunar science and exploration.

Dr. Paul Spudis is the Senior Staff Scientist at the Lunar and Planetary Institute in Houston, Texas. His research focuses on the geological history and evolution of the Moon and processes of impact and volcanism that have shaped its surface.

Nancy Atkinson is a science journalist and is the Senior Editor for Universe Today.

Sponsor:This episode of 365 Days of Astronomy is sponsored by Craig Clark.


Voice: You are listening to the NASA Lunar Science Institute podcast which highlights the latest news information of the Moon, on the Moon and from the Moon. It is produced from the NASA Lunar Science Institute at the Ames Research Center in Moffett Field, California.

Nancy: Many have dreamed of a human settlement on the Moon but will it ever become a reality? Hi, this is Nancy Atkinson for the NASA Lunar Science Institute. With us today is Dr. Paul Spudis, who is the Senior Staff Scientist at the Lunar and Planetary Institute in Houston. He has been studying the Moon for over 30 years and has long been an advocate of having people return to the Moon to live and work there. Hi Dr. Spudis and thanks for joining us.

Spudis: Hi Nancy. Glad to be here.

Nancy: You and a colleague, Tony Lavoie, have come up with a plan for setting up a lunar settlement, and this is a unique system that not only creates a Moon base, but also a type of transcontinental railroad in space which opens up cislunar space – the area between Earth and the Moon – for development. Could you tell us about this idea?

Spudis: Sure. What we propose is to use robotic teleoperated machines, machines that are operated from the Earth to basically go to the Moon and begin to extract water from the polar deposits and use that to make propellant which will then be used to fuel a reusable space transportation system between the Earth and the Moon. So that that plan in a nutshell in one sentence. The reason this is possible is because the Moon is close – it’s only three light-seconds round trip for radio signal get from Earth to the Moon back, which means that you can control machines remotely with operators on the Earth actually doing the activities that an astronaut might do on the Moon. The advantage of this is that it allows you to place a large part of the needed infrastructure, the mining operation, the processing plants, the development of storage for the water and propellant you make from it before people even arrive. So what we try to do is to develop an architecture that enables us to, first, do this and small, incremental steps, each step builds upon the net effect is cumulative over time. And finally were able to bring people to the Moon when we’re ready to actually have them live there. We place an outpost, a habitat that will be fully operational before the first humans arrive.

Nancy: What are the resources on the Moon that could be used and how would they be used?

Spudis: The most important resource that the Moon has to offer is water. In the last four or five years, we’ve discovered that not does the poles of the Moon have water deposits but water is present in significant quantities. We estimate there are many tens of billions of tons of water at both poles. What we don’t know in detail is exactly how much water is distributed what physical state is and that’s one of the reasons why the first step in our plan is to send robotic prospectors up there to map the deposits and see how they vary.

Now water is a very important substance in space. It can be used to support human life, obviously. You can drink it, and crack the water into its component gases hydrogen and oxygen and breathe the oxygen. You can combine hydrogen and oxygen in something called a fuel cell to generate electricity. Actually there’s a smachine called a regenerative fuel cell the basically combines hydrogen and oxygen to manufacture electricity when it’s night time, and during the day use solar power to generate electricity to break that water back into its component gases. So in that sense, water is a medium in which to store energy. It can operate and provide power for the lunar outpost during the night time. Water is a very good shielding material that protects people from cosmic radiation, so one way to protect people from the radiation of the deep space environment is to jacket the habitat with water. And finally most important use of water is, by breaking water into its components, liquid hydrogen and oxygen and liquefying them into their liquid forms, that creates the most powerful chemical rocket propellant known. So the the Moon offers us this water not only to support human life there, but also to make rocket propellant to allow us to refuel our spacecraft both on the Moon and space above the Moon.

Nancy: Could you outline some of the incremental steps that would be taken in this plan?

Spudis: Sure. What we’ve tried to do is to approach the problem of returning to the Moon with small steps. So what we first do is send a series of small robotic missions, to prospect the polls, to map out the locations of where we have large deposits of water, where we have areas of your permanent sunlight to generate electrical power, and then to experiment with digging up the ice deposits, melting the ice and storing the products. Now, all those are simple conceptually, but we’ve never done them in practice so we don’t know how difficult it is. We don’t know what some of the practical difficulties.By sending the small robotic missions to the Moon and practicing this via remote control from Earth, we can evaluate how difficult it is, where the chokepoints are, what are the most efficient ways to get to these deposits and to extract usable product from them. That is sort of the first step. Once we’ve documented that from and end point of view, then we can find a water, extract it from the Moon we could store it and use it for practical purposes. The next step is to increase the magnitude of that effort, to basically land bigger robotic machines that can actually start making product on industrial scales because fundamentally, what we want to do is to create a depot of supplies on the Moon that will wait for the first human humans to go back. So all of this is done by robotic machines that are delivered individually from the Earth on individual missions.

We estimate that we can create an entire turnkey lunar outpost on the Moon within about 15 to 16 years, and humans arrive about 10 years after the initial robotic missions go.

Nancy: And what about the transcontinental railroads in space that would be part of that?

Spudis: If you can go to the Moon and refueled your vehicles on the Moon and from the Moon export water from the Moon to the space between Earth and Moon what is called cislunar space, effectively you have created a system that can not only routinely accesse the Moon come back to the Earth, it can also routinely access all other points in cislunar space, all the points between the Earth and the Moon. The significance of that is, all our satellite assets reside there, for example a communication satellite and weather monitoring satellites are resided in geosychronour orbit, that’s about 36,000 km above the Earth’s equator and right now we cannot reach that from low Earth orbit. That cannot be reached from, for example, from the International Space Station. If we have system that can routinely go back and forth to the Moon though, and refuel there, we could also go to these high orbits where a lot of commercial and national security assets are. So effectively, by building a system that goes to the Moon and learns to utilize the resources the Moon has to offer, we create what is an effect a transportation system that accesses all those points between Earth and Moon. The anaology I like to make is that this is very similar to the Transcontinental Railroad. We didn’t just build the Transcontinental Railroad to from the East Coast directly to the West Coast, we also you’ve built it to access all the points in between and consequently all the points in between were developed economically as well.
Nancy: So does any new technology or rockets or anything like that need to be developed and built for this plan.

Spudis: Not really. Effectively this plan is possible to achieve right now with existing technology. We don’t have any “unobtainium” or any special magical machine that has to be built. It is all very simple outgrowths of existing equipment,, and many cases you can use the heritage equipment from previous missions. For example, if you were to fly a variant of the MER Rovers that are currently exploring Mars at poles of the Moon, they would do a very good job of roving and prospecting for water at the lunar poles. We might have to experiment a little bit with getting the bigger machines, the actual resource processing machines to work but conceptually they’re all very similar so we’re not really trying to pull any rabbits out of a hat. All of this is are simple extensions of existing technology and existing industrial techniques.

Nancy: This certainly sounds exciting. But NASA is facing some possible budget decreases, and definitely no increases in budget the next several years. Is this plan something that will take a lot of money and resources?

Spudis: Well, this is the best part of this. Because we have broken our architecture into small chunks, each mission is largely self-contained and once it gets to the moon it interacts and works with the pieces that are already there. We can do this project at whatever speed the resources permit. So if you have a very constrained budget with very low levels of expenditure, you can go you just go much more slowly. If you have more resources available you can increase the speed and increase the rate of asset emplacement on the Moon and do more in a shorter period of time. So effectively what we’ve tried to do is find an architecture gets us back to the Moon and creates real capability. But the free variable is schedule, not money. So if we are under constrained budget, we progress slowly. If we have a more relaxed budget, we make much faster progress.

Nancy: Well, this is certainly a very intriguing proposition! Why do you feel that returning to the Moon is such an important endeavor for the human race?

Spudis: Well, the Moon is important for many reasons. But I think probably the most important reason for as far as human future in space goes, is what it offers us in terms of resources. By going to the Moon we can learn how to extract what we need in space from what we find in space. Fundamentally that is a skill that any spacefaring civilization has to master. The Moon offers us water which is an extremely useful substance, that I mentioned before, and we know where it occurs and we know how to get to it. And effectively, if you can learn to do that – if you can learn to start using what you find space to create new spacefaring capability, you’ve got a skill that will allow you to go to the planets and in fact a system that can routinely take us back and forth to the Moon can also take us to Mars and beyond.

Nancy: Great! Thank you so much Dr. Spudis for being with us and telling us about this. For more information you can go the to find out more about this intriguing plan. Thank you again.

Spudis: Thank you.

Voice: To find out more about this topic, visit our website at Any opinions expressed are the individuals and do not necessarily reflect the opinion of NASA or the NASA Lunar Science Institute. This podcast is produced for educational purposes only. On behalf of the NASA Lunar Science Institute, thanks for listening.

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