Research Update

by Lee Valentine

Freeman Dyson told me about twenty years ago that he believed that Gerry O’Neill would succeed in opening the High Frontier because he had sitzfleisch, or patience. Patience prevails in the continuing work of your Institute.

What the Institute has accomplished

SSI has had many accomplishments in its 25 year existence including the discovery of the large population of near earth asteroids and the prediction of asteroids, recently discovered, in halo orbits about the Trojan points of the Earth sun system. SSI designed the Lunar Prospector, responsible for discovery of large quantities of hydrogen and, so, presumably water, at the lunar poles. Lunar water will have many economic uses including the support of orbital tourism. The Institute was also responsible for the development of mass drivers and the first studies of lunar and asteroid mining, using mass drivers to retrieve nonterrestrial raw materials. The SSI technique was the first credible method proposed to move asteroids. It has assumed greater importance with the recognition of the threat of NEO impact on our home planet. This work has continued and, thanks to SSI’s relationship with Prospace, the citizen’s space lobby, has led to serious governmental consideration of the asteroid impact problem, a grave problem unrecognized as recently as 20 years ago. Leik Myrabo has said that SSI’s technical assistance cut five years from his development timeline for laser launchers. SSI pioneered the separation of nonterrestrial materials and production of engineering materials from lunar ores. The otherwise excellent NASA Fresh Look at Satellite Solar Power by John Mankins (see the paper at spacefuture.com) completely ignored the use of nonterrestrial materials. Interest in space resources has recently begun to increase.

The Space Resources Roundtable, with SSI participation, has begun to coordinate research on nonterrestrial materials utilization. Significant work remains to be done on the processing of nonterrestrial materials, and SSI will continue to be an essential part of it. This September, your Institute and Prof. William Jewell of Cornell University have completed Phase One of a fully closed ecology life support system, a critical path technology.

Rationale of the Institute

SSI’s research agenda has always sought out projects with very high leverage, that is, a small initial investment that is able to change the course of a much larger enterprise by demonstrating feasibility or an easier or cheaper alternative. An example is the design of the Lunar Prospector spacecraft, before Lunar Prospector, no one at NASA would seriously consider expeditions to the lunar poles in search of water to make hydrogen and oxygen rocket fuel. Now everyone does. Another would be the application of CELSS to space hotels or NASA’s L1 outpost.

SSI’s purpose is to serve as a source of critical technologies to open the High Frontier. A serious and far-reaching problem in O’Neill’s original scheme to settle the High Frontier was the dependence on a very large government program, precisely timed, to allow a real economic return from space. Until now, the history of human spaceflight is a history of large negative economic return over many decades.

The most recent large programs managed by NASA have been vastly over budget and years late. Such management performance would be unacceptable to instantiate SSI’s original concept for space settlements and power satellites. To get around the requirement for an Apollo style project, Dr. Peter Glaser proposed a terraced approach to the construction of solar power satellites. This approach would mimic the fashion in which most large enterprises have begun: building on the technical successes of smaller enterprises and becoming larger and more sophisticated with the accumulation of hard-won knowledge and, at the same time, making a profit in the gradually increasing market. Such an approach is fundamentally more sound than attempting an all-out program like the Apollo project. This stepping stone approach is similar to the economic development of the modern automobile and highway system, the telephone system, and electric power grid. It is useful to remember that the infrastructure of our mighty nation was built bit by bit and that is the way we must develop space. The era of Apollo projects, or Mars projects, for no economic purpose, appears to be long gone.

Because governments are inefficient in their use of capital, Gerry O’Neill felt it wise to develop a plan to use private capital to open the Frontier. SSI has been working diligently over the past decades to develop technology that will enable private industry to open the High Frontier. SSI has always believed that the government model of space exploration for purposes of national prestige is unlikely to lead to permanent space settlement. We have been searching for economic drivers of space settlement since SSI’s beginning. Our intent is to reduce risk through technology development so that viable business plans leading to opening the frontier can be written. Thanks in part to SSI’s efforts, new opportunities, in addition to power from space, have appeared and these are: platinum group metals, closed ecologies for space hotels, and planetary defense. SSI has active involvement with all three. It now appears that there will be an incremental progression of markets to which SSI may supply critical technical know-how allowing a stepping stone approach to space settlement.

Classic markets for space products

Power from space is still an excellent goal, see the article titled Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet by Hoffert et al in Science vol.298, Nov 1, 2002.The first author, Martin Hoffert is an SSI researcher, SSI Director, Prof. John Lewis and Prof. David Criswell contributed.

Supply of engineering materials for space solar power, either on the moon or in high orbit

The development of suitable process methods for nonterrestrial materials to produce useful engineering materials in space is critical. Despite much good pioneering work by SSI and FINDS, we still are in need of well validated processes to give us a variety of materials. Bench scale research is still critically required in this area and SSI plans to continue research until a case can be made, with verifiable numbers, for the use of nonterrestrial materials in support of space solar power, space settlement and other economic activities. Supply of lunar oxygen and water and hydrogen to low earth orbit in support of transportation to high orbit or to the moon may provide important benefits to space tourism.

New markets

Supply of water, air, and food and disposal of waste products on space hotels and deep space outposts as, for example, NASA’s proposed Earth Moon L-1 station. NASA has begun planning for manned excursions out of low earth orbit for the first time in three decades. The NeXT team proposes building a manned station at the earth moon L-1 position. This location has distinct advantages for returning to the moon as well as embarking for near earth asteroids. Because of its proximity to the moon, such a station could also serve as a teleoperations hub for robotic excavation and construction on the lunar surface; time delay makes teleoperation from the earth extremely difficult. One particularly nice feature is that the L-1 libration point remains in sunlight almost continuously. Because of its more distant location, resupply will cost much more than an equivalent mass transported to the ISS. If it is designed to have artificial gravity, a fully closed life-support system could be incorporated to decrease resupply requirements and demonstrate the life support technologies for a minimal space colony. SSI would be in the position to suggest the use of such a system if we are able to complete Phase Two of our closed environment life support system work at Cornell. Right now, our feeling is that the technology is not sufficiently mature to make its adoption by NASA for this purpose likely. Closed environment life-support systems remain absolutely necessary to enable space settlements and manned spaceflight far from the Earth, especially in the continued absence of very high-performance propulsion.

Platinum group metals (PGM) are of enormous and increasing economic interest. Every near earth object has a platinum group metals concentration greater than the best terrestrial ores. The recent rapid progress in fuel cell development is expected to increase the demand for platinum group metals by a large factor over the next few decades. Because of this increased demand a large supply of platinum group metals introduced into the marketplace should not cause collapse of prices, as had been feared in earlier asteroid mining scenarios that assumed a much lower world economic demand for these metals. It appears certain that new ways will be found to decrease the present very large platinum alloy quantity required per kilowatt in fuel cells, nonetheless total demand and installed capacity will exceed the world’s known platinum supply within about six to eight decades.

Some recent projections of world platinum group metals requirement for fuel cells indicate that non terrestrial platinum will be necessary within the next five decades. See Hoffert et al cited above. Current known world reserves of platinum group metals total 170 billion grams. The current best fuel cell catalysts require 0.3 g of platinum alloy per kilowatt. Expectations are that this will decline to about 0.1 grams of platinum alloy within the decade. Platinum metals at a delivered price of seven dollars per gram would under price all terrestrial supplies except for those held in strategic reserves. The discovery of a single 100 meter metallic asteroid in a convenient orbit could provide most of the raw materials necessary for the production of hundreds of gigawatts of Brayton cycle solar power satellites and as a byproduct, thousands of tons of platinum group metals. John Lewis estimates that recovery of these metals as a byproduct of solar power satellite production would be competitive with terrestrial supplies.

It is possible that there are some metallic asteroid impact sites on the moon created at relatively low velocities that contain large quantities of recoverable platinum group metals as well as nickel, cobalt and iron. We have not yet looked for those potential impact sites. The relatively short flight times to the lunar surface may make such implanted ore bodies competitive with known asteroidal sources that are energetically easier to reach but more distant in time and space. A lunar resource mapper spacecraft designed to look for the distinctive radar signature of native metal would be a sensible addition to the small armada of spacecraft heading to the moon over the next few years.

A further market is planetary defense against NEO impact. This is one thing that we must do in space to ensure our survival. The likelihood of a mass extinction impact per century from NEO impact is about one in a million, about one in a thousand is the risk per century of a NEO impact energetic enough to wreck civilization and kill a billion people, and about one in a hundred is the risk that an impact generated tsunami will destroy the U.S. East or West coast in this century. Those numbers should worry us all. Our children and grandchildren will be alive through most of the century. SSI has been in the forefront of studies to deflect comets and asteroids. For the past four years, SSI has produced the educational material used by ProSpace, the Citizens’ Space Lobby, to educate lawmakers in Washington about the threat posed by near earth asteroids and comets. The four color congressional brochure is available from SSI’s web site. This July, SSI sponsored a Senate Roundtable titled the Asteroid Threat: Identification and Mitigation Strategies. A short article detailing the benefits of mass drivers for planetary defense submitted by SSI to the NASA Workshop on Scientific Requirements Mitigation of Hazardous Comets and Asteroids appears on the web at www.noao.edu/meetings/mitigation/eav.html

Mass drivers, indeed, may turn out to be the best option for moving some asteroids. SSI is now looking to fund our cooperative project with the Robotics Institute at Carnegie Mellon University to demonstrate robotic mass driver emplacement, loading and firing. This technology has a dual use. It works as well to return NEO’s to high earth orbit to construct satellite solar power stations or to provision space hotels, or deliver platinum group metals to the terrestrial fuel cell market as it does to deflect threatening near earth objects.

The importance of space tourism in lowering cost of space access

Today the advent of the space tourism market appears to provide a stepping stone needed to open the High Frontier.

An excellent article by longtime SSI friend, Professor Patrick Collins, appears on the spacefuture.com website titled The Cost to Taxpayers of Government Anti-Space Tourism Policy and Prospects for Improvement. This June, the Futron Corp. published a study detailing the demand for space tourism in the affluent world. The study assumes no change in the cost of transportation of people to low earth orbit over the next two decades and the emergence of a suborbital tourism industry. It predicts a multi-billion dollar market by 2020, a market large enough to support the private development of inexpensive reusable space transportation.

The market for earth orbit transportation has been strictly constrained by the relatively small number of launches required by the worldwide communication satellite and remote sensing industry. Since cheap earth to orbit transportation is also critical in enabling space settlement, there has been a great deal of debate among space advocates about how to achieve it. Transportation costs to LEO must be reduced to 1000 dollars per kilogram or less to open new markets in space. Such reductions appear well within the limits of chemical rocket technology little more advanced than we have today but those reductions depend inversely on the flight rate. Space tourism is one market that offers a sufficient flight rate to drop the cost of earth orbit transportation to the range necessary for large-scale human settlement. Unlike satellite solar power, which may also require a high flight rate, space tourism has already begun and has yielded the first economic return, ever, from manned spaceflight.

Fortunately, it appears that space tourism is poised to enter a dramatic growth phase. Within the last year, two piloted, rocket powered vehicles have been developed and flown by private corporations, it appears likely that the X prize will have been won within the next two years and likely that suborbital tourism will begin shortly after that. Of course, suborbital flight is a long way from orbital flight, nonetheless, the engineers responsible for these first vehicles are confident that, with sufficient capital, vastly less than a similar government effort would require, they can build small orbital vehicles to serve the tourism market. Work is afoot in Japan is well. Thanks to Dennis Tito, the giggle factor is now largely gone from space tourism.

Space tourism will further benefit space settlement by providing a market for closed environment life-support systems for the visitors at space hotels. We all understand that closed ecologies are a critical technology for space settlement, but they are vital not just for permanent settlements. Studies conducted by Boeing two decades ago showed that the crossover for a fully closed life-support systems occurred with a duration of about five years. So, it makes economic sense to incorporate a fully regenerative life-support system in the baseline design of any inhabited station with a lifetime more than five years. The trouble is that no one has yet built a completely closed system with the robust functionality necessary to serve this purpose. Until transportation costs to earth orbit are in the range of dollars per pound they will be economically important for LEO hotels, too. When the market to supply space hotels appears, we’d like to be able to support it with our CELSS.

Research progress

Our Solar Blade spacecraft is now undergoing vacuum chamber testing to obtain data to validate our mathematical model of its dynamic behavior. The sails being tested are constructed of 2 micron aluminized Mylar fabric. Simulation of vehicle control is proceeding and shows that the vehicle can satisfy NASA’s mission requirements as well as our intended use as a multiple asteroid rendezvous spacecraft. The limit of scale up of the Solar Blade vehicle is not yet known, but the project engineer, Richard Blomquist expects that a 1000 meter blade will be controllable. A larger spacecraft would use more than the four blades on the flight prototype Solar Blade. The flight prototype is expected to cost at least five hundred thousand dollars and we are still in search of money for construction. We are also looking for a flight opportunity, preferably at no cost to us. I have had preliminary talks with General Pete Worden about the value of our approach in obtaining physical ground truth for multiple asteroids both for planetary defense and for non terrestrial materials utilization. He has indicated interest in SSI’s approach and may be able to assist us in securing a launch.

Robust methods of deep space transportation plainly require further development. For the inner solar system solar sails are promising and SSI will continue to pursue solar sail development.

SSI will concentrate on funding Phase Two of a fully closed environment life-support system. We have made significant progress in developing a completely closed system. The results of SSICornell Phase One has confirmed our belief that a relatively simple biologically based closed environment life-support system is feasible and robust and will provide the technical foundation to support large-scale space settlement. We have reached the point where the funding required to advance this work significantly will require construction of a fully closed system and the participation of several additional experts in other agricultural engineering disciplines. Our principal investigator, Prof. Bill Jewell’s opinion is that the next sensible step would be to build an all up prototype incorporating all of the functionality of a system that could support a small number of people in a completely closed system. His estimate of the time necessary to produce such a system is from between three and five years, with a budget of between two hundred fifty thousand dollars and five hundred thousand dollars per year. His opinion is that both the cost and timeframe would be toward the low end of this estimate. He has done an excellent job for the Institute on a shoestring budget so I’m inclined to go along with his opinion. He did point out that he does worry that we would be tarred by popular association in that objective with the Biosphere people, nonetheless, he feels that a prototype is the next proper step for this research.

He points out that evapotransportation from the plants yields 100 times the daily requirement of water and that proposing multistep physical processes to perform water purification makes no sense. He also pointed out that many of the functions proposed to be done by physicochemical processes in the NASA approach to closed environments can be done by biological systems that are robust and require no particular instrumentation. That is to say, processes that require multiple modules of specialized equipment are subsumed by one, much simpler, biological reactor.

He also notes that incorporation of an aquaculture module or fowl or goats or rabbits to consume crop waste would be highly desirable and would increase the efficiency of food production for the human crew. Feeding crop waste to animals also reduces the quantity of refractory organic waste requiring further processing. The aquaculture module could serve both as shielding and as a necessary reservoir of water.

The crop area used for nitrogen fixation is about 35 percent of the total growing area and might profitably be replaced by a physicochemical process. Such a process could use methane from the anaerobic digesters. It may prove either desirable or necessary to incorporate a small incinerator to handle some part of the refractory biomass.

He feels there should be some scientific interest in this kind of a project by number of people concerned with understanding ecosystems and agricultural economy. There also should be some interest from architects of green buildings.

It is his opinion that 100 percent closure is doable so long as we have plenty of light.

SSI does not now have the resources to undertake Phase Two of this project. This is truly unfortunate since the scientific value of such an effort alone should well repay its cost. We believed, based on earlier work and on fundamental considerations that such closed systems should be realizable and now we know that they are. Over the next couple of months I’ll be putting together a proposal to raise money for the next phase and I would welcome any suggestions you may have. Interestingly, there appears to be a near term nonterrestrial market for such a system since, based on studies of the orbital tourism market by the Futron Corp., the first space hotels are likely to be constructed within the next decade or two

Conclusion

Can we discover a path that allows us to defend the Earth, as we must do, against asteroid and comet impacts and allows us to provide unlimited clean energy to improve our quality of life and the environment of our planet and also allows us to settle the solar system and begin our exploration of the rest of the universe? Can we find a path that allows us to make a profit and improve our technologies step-by-step? I think that there is. The technology for deflecting asteroids is also the technology for returning them for mining purposes. With a cheap source of materials power satellites, broadly understood, may be more than cost-effective; they may provide the cheapest possible electrical power. We need to do the things that enable us to stay on that righteous path. It is possible to envision an energy regime in the next 40 or 50 years that is almost completely powered from space and that furthermore uses platinum group metals largely derived from asteroids to enable a cheap, hydrogen mediated energy sector.

In the past 20 years it has become apparent that we need not go to the asteroid belt in search of accessible resources. This idea is based the quantity of NEOs, a number unknown at the conclusion of the Apollo program 30 years ago. The near earth asteroids were discovered in the middle of the last century, but no one has had a good idea of their numbers until now.

A trickle of discoveries came after the establishment of Spacewatch, a development supported financially by the Space Studies Institute. The Alvarez discovery of the impact demise of the dinosaurs added further urgency to the discovery and accurate characterization of the size and numbers of near earth objects.

Professor Ed Belbruno of Princeton has discovered a clever technique to return mass from these locations to geostationary orbit for a nominal change in delta V using a lunar resonance capture orbit. Many bodies in these highly accessible earth-crossing orbits will also be easily returnable to geostationary earth orbit. Ed Belbruno has done detailed calculations showing that this is so. NEO’s in halo orbits about the Lagrange points in the Earth sun system are no longer hypothetical. A metallic asteroid 100 meters in diameter has a mass of roughly eight million tons, sufficient to construct most of the mass of 80 five Gigawatt satellite solar power stations.

The research needs are obvious, how does one move such an asteroid? How does one cut up and maneuver the fragments of metal? How does one formulate the alloys and fabricate the structures? Although there is a large body metallurgical knowledge on hand that has been developed for terrestrial purposes, that knowledge may not be directly translatable to the space environment. We have our work cut out for us.

Technology for Human Space Settlement