JAXA’s Lunar Farming Concept Study

Cutaway illustration depicting a sublunar farm covered by regolith, providing food and augmenting life support for a settlement on the Moon. Credits: Microsoft Image Creator

The Japan Aerospace Exploration Agency (JAXA) published a report last November summarizing the findings of its Lunar Farming Concept Study Working Group. JAXA’s team, composed of professionals in universities and private experts, assumes that humans will eventually establish permanent communities on the Moon and conducted the study using cutting-edge agriculture science and biotechnology to design a plant factory that would provide nutritional sustenance and oxygen in a life support system for a lunar settlement.

The working group was composed of four subgroups: cultivation, unmanned technology, recycling, and overall system design. The cultivation subgroup focused on the farm’s environmental controls including light levels (provided by LEDs), irrigation and atmospheric conditions tailored to each crop type. The unmanned technology team dealt with robotic maintenance of the plant factory environment including autonomous monitoring, sowing, cultivating and harvesting. The recycling group ensured soil improvement and reuse of limited resources, inedible scraps and waste material. Finally, the overall system subgroup studied the farm as a whole taking into account each plant species.

The scale of the lunar colony in the study was spit into two scenarios. An initial settlement in the near future with a 6 person crew followed by a larger scale permanent community at a later date with 100 people. The objective was to define a scalable cultivation system that would provide energy and nutritional requirements for settlers without resupply from Earth. The design would leverage recycling to fullest extent possible, minimize the use of materials sourced on the Moon such as water and oxygen from the polar regions, and reduce supplies imported from Earth, realizing that the system would not be 100% closed. LED lighting was utilized to optimize wavelength for chlorophyll absorption as well as diurnal growth cycles during the 14 day lunar night, being necessary for crop illumination in an underground farming community protected from radiation by thick layers of regolith. Nuclear power was considered as a power source.

An important finding of the study leveraged a metric called the Equivalent Systems Mass (ESM), to evaluate the life support systems of the different lunar farm designs explored by the team. ESM is a mathematical formula used to perform trade studies to determine which options have the lowest launch cost and is calculated from the system variables mass, volume, power, cooling, and crew working hours. When comparing the ESM of several biomass production systems it was found that the mass of the system could be minimized by appropriate sizing of crop cultivation shelves and increased space utilization efficiency. It was shown that over a 10 year period an optimized design for a lunar farm would not have to be replenished with food from the Earth when building materials, water and oxygen were supplemented by sources on the Moon and nuclear power was assumed as a power source.

The JAXA study adds to the space farming body of knowledge needed for establishing life support systems for space settlement.

Economic benefits from space mining

A fictional depiction of an ore ship servicing mining operations on an asteroid. Credits: DALL∙E 3

The clean energy transition away from fossil fuels promoted by the Biden Administration and other world governments will require significant increases in mining of critical materials for clean energy technology. To support the huge projected growth in solar, wind, and battery technologies over the next few decades, demand for key minerals such as lithium, graphite, nickel and rare-earth metals will balloon significantly according a 2021 report by the International Energy Agency: The Role of Critical Minerals in Clean Energy Transitions. When compared to current supply levels, sourcing of these materials will need to grow by several hundred percent, with lithium in particular predicted to explode by 4,200% to keep pace with the needed battery production for EVs and other energy storage systems. There is insufficient mining capability in the world today to meet this demand, and if capacity were ramped up to these levels, there would be serious environmental and economic consequences. If we ignore other promising alternatives (which SSP does not advocate) such as ramping up licensing of new nuclear fission power plants and funding development of fusion energy or space solar power, what can be done?

In the journal PNAS, a research article makes the case for why mining in space may be a viable solution and help lay the foundation for sustainable growth on Earth. The author’s* objective for the paper was to perform a trade study on the economic outcomes associated with the environmental and social impacts of terrestrial mining compared to the costs of sourcing from asteroids, focusing primarily on metals required for the clean energy technologies such as copper, nickel cobalt and lithium. The methodology of the paper used a neoclassical Ramsey economic model to predict economic growth under those two scenarios. The study quantifies the economic benefits and projected timelines of mining in space for increasing metal use in clean technologies on Earth for the rest of this century and concludes that the reduction in costs due to environmental damage to our planet’s biosphere may be worth the investment in asteroid mining.

Along similar lines another economic analysis by Matthew Weinzierl makes the potential case for an expanding space economy as a solution to secular stagnation, that condition that some economists fear is happening in the US: a chronic lack of demand as if the economy is operating below capacity even when it appears to be booming. Weinzierl says “In simple terms, secular stagnation is the idea that a sluggish outlook for the economy causes people to save more and firms to invest less, and if interest rates cannot fall enough to spur investment (perhaps because of the sluggish outlook), the lack of investment makes the low-growth prospects all the more likely to be fulfilled, initiating a vicious cycle.” How could space development help prevent this problem? Space settlement, i.e. world building, would unlock abundant resources in the solar system to sustain not only capital investment in expanding economic activity, but robust population growth without limits.

An interesting perspective on off-Earth mining as a commercial engine driving a space economy, with a focus on a thriving Martian colony, was proposed a few years ago in a paper by Robert Shishko and others. The study examined the role of space mining in an economy based on mineral extraction, ice/water, and other resources obtained in situ on the Red Planet. The analysis provided a better understanding of the market conditions and technology requirements for that economy to grow and prosper. This approach would definitely benefit from the recent discovery of massive amounts of subsurface water ice under the Medusae Fossae Formation near the equator of Mars.

Mars Express radar image of subsurface water ice beneath the Medusae Fossae Formation near the equator of Mars. Credits: ESA

If an economic case can be made for space mining and funding secured, it will be dependent on the location of the most profitable and accessible space resources in terms of energy and abundance of useful material. Where will this motherlode for space mining be? SSP has covered this debate.

One of the companies on this frontier is UK based Asteroid Mining Corporation which has the goal of becoming the first profitable space resources business. The startup is working on an autonomous robotic platform call Space Capable Asteroid Robot Explorer with a roadmap that plans for revenue payout at each milestone with eventual return of asteroid resources in the mid-2030s.

Asteroid Mining Corporation’s Space Capable Asteroid Robotic Explorer. Credits: Asteroid Mining Corporation.

And of course readers of SSP are familiar with AstroForge, the company focusing on returning precious metals to Earth from asteroids.

Upon full maturation of AI and space-based robotics technology, it will be possible to autonomously restructure an asteroid to construct spin gravity space settlements using materials in situ.

Artist impression of a rotating space settlement under construction using material from an asteroid. Credits: Bryan Versteeg, spacehabs.com

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* Authors of research article in PMAS Mining in Space Could Spur Sustainable Growth: Maxwell Fleming, Ian Lange, and Sayeh Shojaeinia of the Colorado School of Mines; Martin Stuermer of the International Monetary Fund.

Neumann Drive successfully tested in space

Company images of a Neumann Drive at upper left with it’s plasma discharge produced in the lab at upper right overlayed above the Earth from space. Credits: Neumann Space / NASA

Neumann Space has announced completion of initial on-orbit tests of its innovative electric propulsion system, the first of its kind utilizing solid metal as propellent to fuel a cathodic arc discharge to generate thrust via plasma exhaust. The commissioning campaign for the system confirmed that the electronics worked properly and that the thruster fired. Next up: following last December’s launch of the company’s second experiment in space, an engineering demonstration later this year will test that the propulsion system can change the orbit of a satellite.

Neumann Space has already lined up both a customer and a potential space-based source of fuel through a partnership with CisLunar Industries. In this symbiotic relationship, CisLunar will utilize Neumann’s thruster to propel their servicing vehicle that hunts down chunks of metallic space debris which will be captured and delivered to a salvage platform to be recycled into metal propellent via CisLunar’s Modular Space Foundry (previously called Micro Space Foundry). The servicing vehicle can then refuel itself to proceed to its next target. SSP reported previously on this propulsion ecosystem which could literally turn trash into treasure while cleaning up orbital debris.

Conceptional illustration of propulsion ecosystem based on CisLunar Industries Modular Space Foundry process for recycling orbital debris. Credits: CisLunar Industries

The orbital debris issue not only poses a serious threat to human spaceflight in Earth orbit, unless policies and standard practices are implemented to mitigate the issue, remote sensing, climate monitoring, weather forecasting and all commercial activities in space could be at risk, not to mention long term sustainable space settlement. The on-orbit recycling partnership between Neumann Space and CisLunar Industries will help implement the remediation pillar of the National Orbital Debris Mitigation Plan promulgated in 2022 by the White House Office of Science and Technology Policy.

In other news, CisLunar Industries was one of fourteen other companies selected by DARPA for its LunA-10 program, a lunar architecture study that will define commercial activities in an integrated infrastructure for lunar development over the next 10 years. CisLunar will collaborate with industry partners to develop what they call METAL, a framework for Material Extraction, Treatment, Assembly & Logistics in a lunar economy based on in situ resource utilization.

Greater Earth (GE⊕) Lunar Power Station

Conceptual illustration showing the first iteration of the proposed design of a GE⊕ Lunar Power Station beaming power to facilities on the Moon. Credit: Astrostrom

In response to ESA’s Open Space Innovation Platform Campaign on Clean Energy – New Ideas for Solar Power from Space, the Swiss company Astrostrom laid out a comprehensive plan last June for a solar power satellite built using resources from the Moon. Called the Greater Earth Lunar Power Station (GE⊕-LPS, using the Greek astronomical symbol for Earth, ⊕ ), the ambitious initiative would construct a solar power satellite located at the Earth-Moon L1 Lagrange point to beam power via microwaves to a lunar base. Greater Earth and the GE⊕ designation are terms coined by the leader of the study, Arthur Woods, and are “…based on Earth’s true cosmic dimensions as defined by the laws of physics and celestial mechanics.” From his website of the same name, Woods provides this description of the GE⊕ region: “Earth’s gravitational influence extends 1.5 million kilometers in all directions from its center where it meets the gravitational influence of the Sun. This larger sphere, has a diameter of 3 million kilometers which encompasses the Moon, has 13 million times the volume of the physical Earth and through it, passes some more than 55,000 times the amount of solar energy which is available on the surface of the planet.”

GE⊕-LPS would demonstrate feasibility for several key technologies needed for a cislunar economy and is envisioned to provide a hub of operations in the Greater Earth environment. Eventually, the system could be scaled up to provide clean energy for the Earth as humanity transitions away from fossil fuel consumption later this century.

One emerging technology proposed to aid in construction of the system is a lunar space elevator (LSE) which could efficiently transport materials sourced on the lunar surface to L1. SSP explored this concept in a paper by Charles Radley, a contributor to the Astrostrom report, in a previous post showing that a LSE will be feasible for the Moon in the next few decades (an Earth space elevator won’t be technologically possible in the near future).

Another intriguing aspect of the station is that it would provide artificial gravity in a tourist destination habitat shielded by water and lunar regolith. This facility could be a prototype for future free space settlements in cislunar environs and beyond.

Fabrication of the GE⊕-LPS would depend heavily on automated operations on the Moon such as robotic road construction, mining and manufacturing using in situ resources. Technology readiness levels in these areas are maturing both in terrestrial mining operations, which could be utilized in space, as well as fabrication of solar cells using lunar regolith demonstrated recently by Blue Origin. That company’s Blue Alchemist’s process for autonomously fabricating photovoltaic cells from lunar soil was considered by Astrostrom in the report as a potential source for components of the GE⊕-LPS, if further research can close the business case.

Most of the engineering challenges needed to realize the GE⊕-LPS require no major technological breakthroughs when compared to, for example (given in the report), those needed to commercialize fusion energy. These include further development in the technologies of the lunar space elevator, in situ lunar solar cell manufacturing, lunar material process engineering, thin-film fabrication, lunar propellent production, and a European heavy lift reusable launch system. The latter assumes the system would be solely commissioned by the EU, the target market for the study. Of course, cooperation with the U.S. could leverage SpaceX or Blue Origin reusable launchers expected to mature later this decade. With respect to fusion energy development, technological advances and venture funding have been accelerating over the last few years. Helion, a startup in Everett, Washington is claiming that it will have grid-ready fusion power by 2028 and already has Microsoft lined up as a customer.

Astrostrom estimates that an initial investment of around €10 billion / year over a decade for a total of €100 billion ($110 billion US) would be required to fund the program. They suggest the finances be managed by a consortium of European countries called the Greater Earth Energy Organization (GEEO) to supply power initially to that continent, but eventually expanding globally. Although the budget dwarfs the European Space Agency’s annual expenditures ( €6.5 billion ), the cost does not seem unreasonable when compared to the U.S. allocation of $369 billion in incentives for energy and climate-related programs in the recently passed Inflation Reduction Act. The GE⊕-LPS should eventually provide a return on investment through increasing profits from a cislunar economy, peaceful international cooperation and benefits from clean energy security.

The GE⊕-LPS adds to a growing list of space-based solar power concepts being studied by several nations to provide clean, reliable baseload energy alternatives for an expanding economy that most experts agree needs to eventually migrate away from dependence on fossil fuels to reduce carbon emissions. Competition will produce the most cost effective system which, coupled with an array of other carbon-free energy sources including nuclear fission and fusion, can provide “always on” power during a gradual, carefully planned transition away from fossil fuels. The GE⊕-LPS is particularly attractive as it would leverage resources from the Moon and develop lunar manufacturing infrastructure while serving a potential tourist market that could pave the way for space settlement.

Curriculum for Astrochemical Engineering

An engineer pondering chemical processes for use in space learned in an advanced postgraduate course in Astrochemical Engineering. Credits: DALL∙E 3

In a paper in the journal Sustainability a global team of researchers has created a two year curriculum to train the next generation of engineers who will design the chemical processes for the new industrial revolution expected to unfold on the high frontier in the next few decades.

Current chemical engineering (ChE) training is not adequate to prepare the next generation of leaders who will guide humanity through the utilization of material resources in space as we expand out into the solar system.

Astrochemical Engineering is a potential new field of study that will adapt ChE to extraterrestrial environments for in situ resource utilization (ISRU) on the Moon, Mars and in the Asteroid Belt, as well as for in-space operations. The body of knowledge suggested in this paper, culminating in Master of Science degree, will provide training to inform the design ISRU equipment, life support systems, the recycling of wastes, and chemical processes adapted for the unique environments of microgravity and space radiation, all under extreme mass and power constraints.

The first year of the program focuses on theory and fundamentals with a core module teaching the physical science of celestial bodies of the solar system, low gravity processes, cryochemistry (extremely low temperature chemistry), and of particular interest, circular systems as applied to environmental control and life support systems (ECLSS) to recycle materials as much as possible. Students have the option to specialize in either process engineering or a more general concentration in space science.

For the process engineering option in year one, students will learn how materials and fluids behave in the extreme cold of space. This will include the types of equipment needed for processes in a vacuum environment including microreactors and heat exchangers, as well as methods for separation and mixing of raw materials.

In the space science specialization, year one will include production of energy and its utilization in space. Applications include solar energy capture and conversion to electricity, nuclear fission/fusion energy, artificial photosynthesis, and the role of energy in life support systems.

In the second year, students learn basic chemical processes for ISRU on other worlds. Processes such as electrolysis for cracking hydrogen and oxygen from water; and the reactions Sabatier, Fischer-Tropsch and Haber-Bosche for production of useful materials.

The second year process engineering specialization focuses on ISRU on the Moon with ice mining, processing regolith and fluid transport under vacuum conditions. Propulsion systems are also covered including methane/oxygen engines, hydrogen logistics, cryogenic propellent handling in space and both nuclear thermal and electric propulsion. Space science specialization in year two covers life support systems and space agriculture.

A design project is required at the end of each year to demonstrate comprehension of the concepts learned in the curriculum, and is split between an individual report and a group project.

Coupled with synthetic geology for unlocking a treasure trove of space materials in the Periodic Table, innovative equipment for ISRU on the drawing board and research on ECLSS, Astrochemical Engineering will be a valuable skill set for the next generation of pioneers at the dawn of the age of space resource utilization.

Progress on mammalian reproduction in microgravity

AI generated image of an expectant mother with her developing fetus in Earth orbit after mammalian reproduction has been validated via higher animal models through all stages of pregnancy for a safe level of gravity. An appropriate level of radiation shielding would also be required and is not shown in this illustration. Credits:DALL∙E 3

We are one step closer to determining the gravity prescription for human reproduction in space. Okay, so we still don’t have the green light for having children at destinations in space with less than normal Earth gravity or higher radiation environments….yet. But a team of Japanese scientists report positive results after running an experiment aboard the International Space Station in 2019 that examined mouse embryos cultured in both microgravity and artificial gravity in space, then compared them to controls on Earth after a few days of development. The researchers published their results in a paper in iScience.

The researchers developed equipment and a protocol for freezing two-cell embryos after fertilization on the ground and launching them to the ISS where they were thawed then split into two groups, one allocated to growth in microgravity, the other treated with spin gravity to artificially simulate 1g. A control group remained on Earth. The procedure was designed to be executed by untrained astronauts. Cultured growth continued for 4 days after which the samples were preserved and refridgerated until they could be returned to Earth for analysis.

The samples were also monitored for radiation with a dosimeter and as expected aboard the ISS, were exposed to radiation levels higher then developing fetuses experience on the ground but far lower than those known to exist in deep space outside the Earth’s atmosphere and protective magnetic field. Still, this can be a “worst case” data point for radiation exposure to developing embryos as it is unlikely that pregnancy would be ethically sanctioned at higher levels.

Upon thawing by astronauts, the embryos were cultured through initial mitosis to eventual cell differentiation and blastocyst formation. A blastocyst is the multicellular structure of early embryonic development consisting of an an outer layer of cells called the trophectoderm surrounding a fluid-filled cavity in which an inner cell mass (ICM) called the embryoblast eventually develops into the embryo.

The study was concerned with how gravity may influence cell differentiation, the placement of the ICM within the blastocyst and if radiation effects gene expression in the these cells which will later develop into the fetus. Gene expression within the trophectoderm is also critical for proper development of the placenta.

The results were very promising as the data showed that there were no significant effects on early cell differentiation during embryo development and that proper gene expression manifested in microgravity when compared to 1g artificial and normal Earth gravity.

A human blastocyst with the inner cell mass at upper right. Credits: Wikipedia

A highlight of the paper implied that the results indicate that “Mammals can thrive in space.” It is too early to make such a bold statement with only this one study. It should be noted that this experiment only focuses on one early stage of embryo development. Conception in microgravity is not addressed and as pointed out by Alex Layendecker of the Astrosexological Research Institute, may have a whole other set of problems that raise ethical concerns as may the effects of lower gravity on later stages of gestation, in actual live birth and in early child development.

No matter how positive these recent results appear to be for early embryo development, as was determined by a landmark experiment on pregnant mice during the Shuttle era, we already have a data point on mammalian fetal development in later stages of gestation in microgravity: serious brain developmental issues were discovered in mice offspring born after exposure to these conditions. So mammalian reproduction in microgravity may start out relatively normally (assuming conception is successful) but appears to have problems in later stages, at least according to the limited data we have so far. On the bright side, the recent study found that 1g artificial gravity had no significant effects on embryo development.

Clearly more data is needed to determine which level of gravity will be sufficient for all stages of mammalian reproduction in space. Fortunately, SpaceBorn United is working on this very problem. They have plans for research into all stages of human reproduction in space to enable independent human settlements off Earth. SpaceBorn CEO Egbert Edelbroek in a recent appearance on The Space Show described upcoming missions later this decade that will study mammalian conception and embryo development using the company’s assisted reproductive technology in space (ARTIS). They have developed a space-embryo-incubator that will contain male and female mouse gametes, which upon launch into orbit, will initiate conception to create embryos for development in variable gravity levels. After 5-6 days the embryos would be cryogenically frozen for return to Earth where they would be inspected and if acceptable, placed in a natural womb for the rest of pregnancy and subsequent birth. If successful with mice the the company plans experiments with human stem cell embryos and eventually human gametes.

The gravity prescription for human reproduction in less than normal Earth gravity is still not known. But at least researchers are starting to gather data on this critical factor for long term biologically sustainable space settlement.

Why settle space?

Artist depiction of the interior of a cylindrical space colony during an eclipse of the sun. Credits: Don Davis / NASA Ames Research Center

This question has come up a lot lately in the press, usually in the context of how public funds should be spent in space.  On the affirmative side, the answer has been addressed well by many space advocates over the years. Elon Musk wants to make the human race a multi-planetary species in case of a catastrophe on Earth and to expand consciousness out into the cosmos starting with Mars. Jeff Besos wants to move industrial activity off world and eventually fulfill Gerard K. O’Neill’s vision of trillions of people living in free space colonies. When asked the question last year by American Enterprize Institute’s James Pethokoukis, Robert Zubrin said: “In order to have a bigger future. In order to have an open future. In order to open the possibility to create new branches of human civilization that will add their creative talents to the human story. ” He thinks Intellectual Property will be the main export of a Mars colony and he’s already kickstarting that process with the Mars Technology Institute. And of course, The National Space Society (NSS) provides clear rationale in the introduction to their Roadmap to Space Settlement.

On the negative side, there are many naysayers. Some even say humans will never live in space. NSS Board Member Al Globus does a great job of refuting these viewpoints.

In an effort to gain deeper insights and clarify the vision of space settlement, SSP reached out to several space advocates, academicians and entrepreneurs to gather as many viewpoints as possible. They were asked if they agreed with the viewpoints above or if they had a different take.  Regardless of if we are asking for public support for government efforts through space agencies, if the efforts will be funded by private individuals or through a combination of public/private partnerships, why should humanity settle space? Here are their answers:

Doug Plata MD MPH, President & Founder of the Space Development Network, makes the case that there is no need to convince the public of the value of space:

“Many space advocates argue that the general public needs to be convinced of the value of space if we are ever going to see space development occur. So, these advocates come up with a wide variety of arguments including: the necessity of securing large amounts of public funding, the value of satellites in our everyday lives, the potential for a huge “space economy”, inspiring the next generation, and even for the survival of the human species.

“But is convincing the general public actually necessary? Put another way, will off-Earth settlement be impossible unless polls show a large percentage of the public supports space settlement?

“Secondly, it is not the general public who will be deciding whether they will settle on the Moon and Mars. Specifically, the uninterested, the cynical, nor the leftist opponent will need to be convinced over their objections. The ones who will decide will be countries choosing to send their hero astronauts to represent their own people and also private citizens who have saved up enough money. If countries have national pride (practically all) and if there are any “early adopters” with enough savings to pay for their ticket and stay, then it will be those who will decide to go. From Elon’s first BFR presentation (Guadalajara), this has been his business case and I find it to be sufficient. We don’t have to imagine some sort of unobtanium to trade with Earth to figure out where the funding will come from.

“For starters, much of the recent progress in space has not been the result of a groundswell of support from the public. Both Elon Musk and Jeff Bezos started their path to radically reducing the cost of launch independent of any groundswell of support for space by the public. And it is significant to note that they obtained their considerable wealth thanks to their Internet companies that had little, if anything, to do with space. It is their vast wealth that now gives them the ability to develop the reusable rockets which will make space development and settlement affordable and, as a result, inevitable. Even if NASA’s budget is cut to zero, Bezos will still have 20 X the wealth of NASA’s annual human spaceflight budget with Musk’s wealth at 30 X. And both are making progress with their heavy lift vehicles in a significantly more cost-effective manner than NASA.

“In conclusion, the cynic cannot be convinced, and it is probably a waste of time to try. But for those who have their own reasons for wanting to go, so long as the price has been brought down low enough…it is they who will inherit the stars. To each his own.”

Image of the Space Development Network’s full-scale mockup of an inflatable permanent habitat for the Moon or Mars at ISDC 2023. The concept is intended to demonstrate how a 100 tonne SpaceX Starship payload could be delivered and deployed to create a habitat with a 1 acre footprint. Credits: Doug Plata / Space Development Network

Dr. Daniel Tompkins, an agricultural scientist and founder of GrowMars weighs in:

“To address the term settlement from a biological view, for me it means to settle on a process or methodology to sustain and expand water/food/housing. There is settling the land to provide these things (where and how to get clean water, grow/harvest food, get building material). there is settling on practices that are reproducible with multi generational intent. Building schools, planning for expanding population. Different than an oil platform or remote research center which aren’t considered sea steading or settling Antarctica for the multigenerational intent reason.

“To answer directly on various views, mixed on positions:

“Musk- agree Mars is “easy” and most scaleable [sic]. Disagree that sustainable cites or a million people is a magically successful benchmark. Showing ability to support expanding population regardless of scale is important. How do you go from the resources to support 2 people, to 4 people.

“Zubrin- practical and pragmatic about challenges for human missions to Mars and how they can potentially accelerate the science and search for life beyond Earth. Agree IP is best export to support Mars economy lb for lb., particularly genetic engineering and synthetic biomanufacturing. Also agree on term resource creation vs term ISRU.

“Bezos- Moon is more difficult then Mars to “settle” lacking useful carbon and nitrogen than Mars, but opens a bigger range of options for where we can, the trillion people in the solar system model. The thermodynamics of habitats and greenhouses in these places isn’t well established or realized and there are misconceptions to this point of Mars being too cold.

“NSS- disagree with undertone of unlimited power needed to solve for space and earth to bring post scarcity. Unlimited biology vs unlimited power argument.

“O’Neill mostly addressed in above views, specifically cylinders are inspiring, but the process to make them not shown to make people think reproducible. Also, micrometer impacts.

“My short response to the space community and wider is that regardless of where in space (orbit, lunar, Mars etc.), space settlement is about learning to thrive independent of Earth’s natural resources in extreme environments. Whether we go to space or not, we are going to have to solve the same problem sets, i.e. clean air, water, food, materials on Earth in 50-100 years, if not sooner. It means you don’t have to fight with [your] neighbor or chop down the rainforest for more resources, you can do resource creation anywhere on Earth and meet basic needs.

“Space settlement level hardware should not be an eventually, it can be smaller than traditional mission payloads and de-risk certain mission architectures. Which is less mass/volume. Food for 3 years, greenhouses, or a machine to make greenhouses? Some of all three would be good, especially in certain scenarios.

“With sustainable independent settlement as a benchmark, practices and processes need to be inherently reproducible and serviceable. Similar and inspired methods could be used on Earth with limited resources in extreme environments to bootstrap resource creation to meet basic needs.”

Conceptual illustration of a habitat on Mars constructed from self-replicating greenhouses. Credits: GrowMars / Daniel Tompkins

Dr. Tiffany Vora, VP of Innovation Partnerships at Explore Mars and Vice Chair of Digital Biology and Medicine at Singularity University, had the following take:

“In my mind, there are three big arguments in favor of humans moving off-planet for extended, if not permanent, habitation.

“First, we more or less have the technologies that we need in order to do so, as well as a burgeoning space economy. I view crewed space habitation and settlement as further spurs to technological and economic development that will drive deeper understanding of the world around us while creating jobs and, hopefully, prosperity beyond a privileged few. That technology development has the added benefit of improving life on Earth, for example by contributing to solutions to the UN SDGs—on the way to setting the stage for sustainable human habitation off Earth.

“Second, as a biologist, I simply cannot believe that we are alone in the universe. I can’t even bring myself to believe that we’re alone in the Solar System! I view exploration and long-term settlement as key components of finding life off Earth, learning how it works, and learning from how it works. Serving as stewards of non-Terran life would be a momentous responsibility for humanity; although we have a dismal record of that here at home, I believe that life anywhere in the universe is a precious thing that would be worth a deep sense of obligation on the part of humans. Alternatively, failing to locate life elsewhere in the Solar System could provide strong messaging about the fundamental science of life—and hammer home the precarity and beauty of life on Earth.

“Third, I still believe in the capacity of space to inspire people, across generations and boundaries and even ideologies. The goal of settling space isn’t only about setting boots on exotic landscapes: it’s about staring at unbelievably complicated and dangerous challenges and saying, “Let’s do this—and here’s how I’m going to help.” I grew up in Florida, standing in my backyard watching shuttle launches. I have never lost the feeling that I had as a kid, witnessing that. I want every child on Earth to feel that sense of inspiration, of desperate excitement about the future—as well as a compelling urge to be part of it. Sure, I’d love for that to inspire STEMM careers, but there are so many other ways to contribute!

“Obviously, every word that I’ve written here comes with its own caveats. But just as I believe in these words, I also believe in our ability to make choices that open up an abundance of possible futures to bring prosperity and peace, not just to as many people around the world as possible, but to our own planet. The key is choices, and those choices have to be made starting today.”

Science journalist and historian Robert Zimmerman in his book Genesis, The Story of Apollo 8, wrote this:

“The new century will see a renaissance of space exploration as exciting and as challenging as the space race in the 1960s. And this rebirth will happen under the banner of freedom and private property, the very principles for which the United States fought the Cold War.”

Zimmerman continues:

“In a larger more philosophical perspective, we settle space because that’s what humans must do. It is the noblest thing we can do. To quote myself again, this time from my 2003 history, Leaving Earth:

‘Our hopes and dreams are a definition of our lives. If we choose shallow and petty dreams, easy to accomplish but accomplishing little, we make ourselves small. But if we dream big, we make ourselves great, taking actions that raise us up from mere animals.’ “

“Earthrise” image taken by astronaut Bill Anders from Apollo 8 on Christmas Eve 1968. Note that this is the original orientation of the image. As pointed out by Zimmerman, it was rotated 90o by the press for dramatic effect. Credits: William Anders/NASA

Entrepreneur and inventor Ryan Reynolds had a refreshingly unique perspective:

“So, why should humanity settle space (remotely and in-person)?:

  • To be confronted with a new set of challenging environments.
  • Feel the struggle to understand and adapt to them. 
  • Benefit from the effort through shared insights and tangible gains for all. 
  • To observe ourselves outside of the cradle, and know better what we are. 
  • To gain a broader view of our kinship with all that exists. 
  • To be surprised and appalled at our behavior out there. 
  • To ensure that the story does not end here. 
  • To extend biology’s reach.”

Dr. Peter Hague, an astrophysicist in the UK who blogs on Planetocracy had this to say:

“The solar system can and will, eventually, support civilisation on a more larger scale than exists on Earth. There is 2 billion times as much energy available from the Sun in the wider solar system as falls on the Earth alone, and huge reserves of raw materials. The composition of this civilisation will be determined by which nations make investments now – they will get to populate the new society, set the rules and inspire the culture. So it’s in the interests of nations to have a stake in the future, or be irrelevant in a few centuries.”

Haym Benaroya, Distinguished Professor of Mechanical and Aerospace Engineering at Rutgers University and author of Building Habitats on the Moon provided these views:

“I often have to defend the efforts and resources that have been used, and will continue to be allocated, for the space program, and especially the manned space program. While one can rightly say that the funds expended is miniscule as compared to other things that governments and people spend vast sums on, this argument rings hollow. I prefer to point to space, its exploration and its settlement, as an open-ended human adventure and imperative that provides young generations a positive vision of their future, one that gives hope to them and their decedents. Simultaneously, it offers the likely significant technical developments that would not occur otherwise. These technologies will impact how humans will live. Their health will improve, their lives will be longer, more fulfilled, and with the potential for great achievements. There is also the hope that with greater abundance for all on Earth, which a potentially vast space economy can provide, the tolerance for wars will decline. This last idea is a bit utopian given the history of the human race, but it is not a fantasy. It is a potential. Space can increase that potential in a major way.”

Dr. David Livingston, creator/host of The Space Show and one of today’s foremost authorities on the New Space economy, had this thought-provoking vision:

“Space settlement is a visionary long-term project.  In addition, I’m confident that be the inevitable outcome pushed by a global humanity wanting to go to space for off-Earth experiences, living off-Earth and eventually creating off-Earth communities.  I see it as a natural outgrowth of innovation, advancements in all walks of life and in our desire to see and check out what lies just around the corner.  Over time this will happen within the private commercial section of our economy with government mostly working to provide enabling rules of the road to mitigate some risks and uncertainty through establishing order and reasonable protocols. To breathe life into this vision so that it becomes reality, collectively we need to anchor our vision in science, engineering, medical development, behavioral science and most likely many more foundational components so that what we build and stands the test of time on solid footing. Having a dream and a vision for space settlement is one thing but to work on it, to enable it, to develop it, to make it come about implies we are a free people able to pursue dreams, to turn them into reality and to create amazing outcomes that were not even in existence yesterday. But its not enough to just have a good dream or vision for the future. We need to be able to make it happen which to me implies having a solid foundation not Bay Mud, plus realistic, plausible outcome expectations that are only possible when we can explore, build, and develop as we see fit. When we can take risks.  Being free to push forward to what lies beyond Earth is as essential as all the other ingredients that will go into making space settlement happen because without that freedom, we will have our dreams but without the ability to make them real.

“I’m fully aware that the settlement discussions like to focus on operational timelines, rockets, engineering, medical, food, and all sorts of challenges.  While all of this is critical to developing space settlement, these discussions must not sidetrack us into a world of hypotheticals and perspectives suggesting this or that technology is best given our present state of settlement R&D. Since I firmly believe that the private sector should make settlement happen, more so than the government, I would like to see viable commercial projects and startups designed to enable and support the goal of settlement. Government too has an important role in establishing space settlement. Rules of the road and policies are needed to provide order, structure, and safety.  One of our primary relationships with government must be oversight so that we enable not curtail settlement development.

“Space Settlement is fraught with challenges, with naysayers and those that think they know best for others.  I have every confidence that we will in time be overcome these obstacles.  By showing and doing, not by talking and promising.  I’m in less of a hurry to see the first settlement than I am in seeing us get started with essential precursors such as long-term commercial project financing as an example.  Space settlement will likely evolve because of a step-by- step methodical approach to information and fact gathering, problem solving, testing, development, and more testing. Risk taking will play a very large role in our ability to move forward.  As for risk taking, it can only be taken by those with the freedom to do so. As we advance step by step, innovation and forward thinking by those on the front lines will play an increasingly valuable role in turning our vision into reality.

“Space settlement is and should be a global endeavor with unlimited motivating and inspiring reasons driving thousands if not millions of us to our goal. As we move forward, we are sure to uncover and use many of the tightly held secrets of our universe. For sure it will be a very exciting and rewarding adventure as we figure out how to live, work, and play off-Earth, all the while making sure the process and our off-Earth communities are sustainable and independent on an ongoing basis.  This will happen if we remain focused and avoid distraction. Having patience will help us stay the course and to develop and maintain our needed drive into the future.  A future that to me lies ahead of us with as much certainty as does our daily sunrise and sunset.”

Tom Marotta, CEO of The Spaceport Company and Brett Jones, Strategic Marketer and Frontier Tech investor cowrote this inspiring response:

Reimagining the Stars: A Multiplanetary Mindset for a Flourishing Future
The challenges humanity faces today are vast. From the instability of our global systems to the dwindling resources and fading hopes, there’s an undeniable sense of stagnation. Yet, within this atmosphere of despondency lies a beacon of hope, a path toward rejuvenation: the cosmos. Imagine a world where resources are not just abundant, but practically infinite. Where our collective potential is not limited by the boundaries of our blue planet, but instead, expanded by the boundless wonders of space. Such a vision is not mere science fiction; it is a future within our grasp.

Space: An Oasis of Resources and Possibilities
Outer space is not just about twinkling stars and distant planets. It’s a treasure trove waiting to be explored. The vast quantities of materials and energy floating in the cosmic expanse can fuel economies, revitalize our planet, and secure prosperous futures for generations. And it’s not just about physical resources. The challenges of space exploration will drive advancements in healthcare, technological innovation, and even the social fabric of society.

New Frontiers, New Beginnings
Space offers a fresh canvas, an opportunity to redefine human existence. For those yearning for change, be it a new environment, companionship, or the thrill of exploration, the cosmos holds endless possibilities. It’s not just about survival; it’s about thriving in ways we have yet to envision.

Redefining NASA’s Mission: From Pride to Purpose
NASA has always been a symbol of American pride. Its achievements, from landing on the moon to exploring the distant reaches of our solar system, are testament to human ingenuity. Yet, its true potential lies not just in exploration, but in transformation.

“For NASA to truly leave an indelible mark on every individual, it needs to shift its vision. Instead of focusing solely on exploration and scientific endeavors, the emphasis should be on providing direct benefits for every citizen. This involves prioritizing space settlements, harnessing energy from space, and leveraging cosmic resources.

An Invitation to the Stars
As we stand on the cusp of a new era, we must choose the trajectory of our future. By adopting a multiplanetary mindset, we’re not just securing a better life for ourselves but ensuring the continued growth and prosperity of all humankind for millennia to come. The universe beckons, offering hope and possibilities. It’s up to us to answer the call.”

Conceptual illustration of a mobile offshore launch platform as part of a robust launch industry infrastructure servicing thousands of launches in the near future to support space development. Credits: The Spaceport Company

Daniel Suarez, author of Delta-V and Critical Mass, believes we should rephrase the question:

“The question of ‘why’ humanity should settle space has been debated ever since it became technologically possible in the late 1960’s and early 1970’s. And the question has renewed relevance here in 2023 with the launch of a new space race — both public and private. A frequent objection is: “Why should we spend precious resources on space development when we have pressing problems to solve down here on Earth?”

“However, to address that concern I think it’s vital to re-frame the question as not just ‘why’ we should settle space, but why we must urgently settle space. And the answer is compelling: we must settle space in order to deliver economic opportunity and clean energy to all the people of Earth, particularly if we are to have a reasonable chance of resolving the existential threat of climate change. One may question how expanding human society and industry into space accomplishes that, but the answer is straightforward…

“Yes, developed nations have made progress in reducing their carbon emissions in an effort to address climate change. And yes, more consumers are buying electric cars. However, social media and mainstream news reports tend to suggest climate change will soon be under control if we just continue installing solar & wind farms, and keep buying electric cars. However, the truth is that human civilization as a whole is not reducing carbon emissions. In fact, for all our efforts over the past 30 years all we’ve done is slow the growth of emissions. For example, global carbon emissions increased yet again (0.9%) in 2022 and that increase was above the 6% increase from the year before (source: National Oceanic & Atmospheric Administration). Pointedly, carbon emissions have increased almost every year since the dawn of the industrial age in 1850 (a notable exception being 2020, during the height of the pandemic).

“The amount of CO2 in the atmosphere today was last experienced 4.3 million years ago, during the mid-Pliocene epoch when sea levels were 75 feet higher than today, and average temperatures were 7 degrees Fahrenheit warmer than pre-industrial times. Even if we reduced annual global carbon emissions to zero tomorrow, average global temperatures would still continue to rise each year for a century or more because of the trillion tons of CO2 that we’ve already released into our atmosphere since 1850. That CO2 will take a century or more to be sequestered by the natural carbon cycle, which means there will be a surplus of heat absorbed by the planet each and every year no matter how many solar panels, wind turbines, and hydro power stations we install.

“No, in order to truly address climate change, we’re going to need to remove CO2 from Earth’s atmosphere, reducing concentrations from the present 418ppm down to at least 350ppm, a level more suitable to global civilization. But coming up with the terawatts of clean energy required to remove all that CO2 is going to be nearly impossible here on Earth, especially as economic and political turmoil continues to spread in response to climactic chaos.

“Adding to the challenge of resolving climate change is the fact that over 2 billion people currently live in poverty and billions more experience meager living standards. They are eagerly trying to improve their circumstances through economic development and increased energy usage. India, China, nations of Africa, and elsewhere want to improve the lives of their citizens just as developed nations of the West did over the past 150 years. They need energy to do so, and new coal and gas-fired power plants are coming online in the developing even as they continue to roll out solar and wind.

“How can we possibly increase the energy and resources available to the people of Earth without further polluting our already ailing home world — especially in time to stave off the worst effects of climate change, which will itself cause more conflict, uncontrolled migration and food shortages, reducing cooperation on global issues? Earth is a finite system, and the solution to climate change and continued economic development worldwide lies in going beyond Earth’s atmosphere to obtain the energy and resources we need.

“One answer is to expand carbon-intensive industry and energy generation into cislunar space. By using in-situ resource utilization in deep space (as opposed to launching all our working mass from Earth), we can start to rapidly build out an offworld industrial infrastructure & economy, using resources harvested from our Moon and near-Earth asteroids. By refining these materials in space, we can build enormous solar power satellites, place them in geosynchronous orbit, and beam at first gigawatts and later terawatts of clean solar power to rectennas on the Earth’s surface 24-hours a day, rain or shine anywhere in the hemisphere beneath them. The technology to accomplish this has existed since the mid-1970’s. And Earth’s geosynchronous orbit, safely populated with solar power satellites could return well over 300 terawatts of continuous clean energy — and for reference we currently consume a bit over 20 terawatts of energy worldwide.
Plus, the economic growth made possible by expanding industry and energy generation into cislunar space will be critical for all the people of Earth. This could include industries only possible in the microgravity and/or near-perfect vacuum of space, from ultra-clear ZBLAN fiber optics, exotic alloys, pharmaceutical discovery, astronomy — the list goes on.

“So ‘why’ should we settle space? I contend that’s the wrong question. The right question is ‘why should we urgently‘ settle space? And the answer is to avoid an existential catastrophe and instead make possible a promising and dynamic future for countless generations to come.”

Artist depiction of a space-based solar power satellite collecting sunlight and converting the energy to microwaves for beaming to rectennas on Earth to be fed into a country’s power grid. Credits: © ESA – Andreas Treuer

Finally, here are the reasons for space settlement articulated as goals in 1976 by Gerard K. O’Neill from his blueprint for migration off Earth, The High Frontier:

  • Ending hunger and poverty for all human beings
  • Finding high-quality living space for a world population which will double withing forty years, and triple with another thirty, even if optimistic estimates of low-growth rate are realized
  • Achieving population control without war, famine, dictatorship, or coercion
  • Increasing individual freedom and the range of options available to every human being
Cutaway view revealing interior of a toroidal space settlement. Credits: Rick Guidice / NASA Ames Research Center

Progress on automated deployment of lunar habitats

Automated deployment sequence of a prototype lunar habitat floor plate structure using a gas inflation system. Credits: Luke Brennan

It is obvious that establishing settlements on the Moon with be difficult. It’s a harsh environment presenting many risks to the health of humans who may wish to live there including radiation, bombardment by micrometeorites, lack of breathable air, and a host of other hazards which will demand rigorous engineering solutions to design safe and livable structures. But Haym Benaroya, professor of mechanical and aerospace engineering at Rutgers University is up for the challenge. In fact, he literally wrote the book on engineering approaches to building lunar habitats. He and his students have been developing novel methods for automated deployment of structures to house future lunar explorers. These type of engineering solutions would allow deployment of large habitable structures prior to the arrival of occupants, thereby minimizing radiation exposure. SSP has had the privilege of covering one such novel approach that combines a foldable rigid framework with an inflatable dome called the Hybrid Lunar Inflatable Structure, the subject of the master’s thesis of one of the professor’s students, Rohith Dronadula.

In a recent paper in Acta Astronautica, a group of Benaroya’s students further refined this approach. Luke Brennan, coauthor on the article, provided the following remarks on progress of the design effort:

“The hybrid lunar inflatable structure (HLIS) underwent three years of development by student teams at Rutgers University to go from an initial concept laid out by Dronadula and Benaroya [2021] to a functioning proof of concept. The design combines safety elements found in rigid structures with the large habitable volumes offered by inflatable designs through an inflatable membrane attached to the rigid center column. The baseplates are folded during transportation to better fit within rocket payloads and can be deployed autonomously once on the lunar surface. When unfolded, the structure expands 2.25x in diameter, representing a 5x increase in floor area.

“Manufacturing constraints set the foundation for the design process. Ensuring an autonomous deployment is key, as the threat of radiation posed to astronauts on the lunar surface restricts them from being able to reasonably assist in constructing the structure. A novel deployment mechanism was introduced, which used a dynamic O-ring to displace and initiate baseplate deployment and membrane inflation. Compressed air will need to be included in habitats regardless of the deployment strategy, so the deployment utilized this by triggering deployment when the gas is released. The internal pressure acts on the component containing the dynamic O-ring, lifting it. The displaced component is attached to the top cap, which contains the baseplates when stowed, and releases the baseplates when lifted. The full displacement of the O-ring exposes an air passageway through the center column, allowing gas to escape into the membrane.

“The first image [above] demonstrates this working concept, where generic SodaStream bottles were used inside the center column with a solenoid to toggle the CO2 release. Unfortunately, as CO2 gets released, the temperature drop can lead to solid CO2 (dry ice) accumulating at the pressure reducer. This ultimately starved the flow, preventing a full bottle from being emptied, which was necessary for proper membrane inflation. This can be resolved using a heated pressure reducer but introduces significantly more complexity, so this was neglected. However, the working proof of concept provides a great platform for future research to build on.”

This work exemplified the key takeaway Benaroya makes in his book Building Habitats on the Moon: “…we need to understand how the reliability of engineered systems can be improved in the unforgiving space and lunar environment and, synergistically with reliability, how to ensure that humans and other living systems can survive and thrive physically and psychologically in that environment.”

Artificial photosynthesis for production of oxygen and fuel on the Moon and Mars

Image of ice in a crater on the Martian plain Vastitas Borealis captured by the European Space Agency’s Mars Express orbiter. Credits: ESA/DLR/Freie Universitat Berlin (G. Neukum)

When we establish outposts and eventually, settlements on the Moon or Mars it would be economically beneficial if we did not have to create supply chains from Earth for water, breathable air and the fuel we will need for our rockets. This is why sources of water ice in the permanently shadowed craters at the lunar poles and in glaciers in the equatorial regions on Mars are so attractive as early destinations. Once we get there what equipment will we need to process this valuable resource? The typical way envisioned for cracking water in situ on the Moon or Mars to produce oxygen and hydrogen is through electrolysis. But this method requires a lot of power. There may be a more efficient way. New ESA sponsored research by scientists* in the UK and Europe examines a novel method that mimics photosynthesis in plants using a photoelectrochemical (PEC) device. The findings were published June 6 in Nature Communications.

PEC reactors are currently being studied on Earth for water splitting to produce green hydrogen from sunlight. Since they only rely on solar energy for power they are ideal for space applications. One type of device consists of a semiconductor photocathode immersed in an electrolyte solution that absorbs solar energy for a reaction to split hydrogen from water molecules. Oxygen is produced at the anode of the cell. PEC devices can be fabricated as panels similar to photovoltaic arrays. For use on Mars, the authors analyze another similar PEC technology using a gas-diffusion electrode to reduce atmospheric carbon dioxide in a reaction producing methane for rocket fuel.

The authors modeled the performance of these devices subjected to the expected environmental conditions on the Moon and Mars. Specifically, they looked at attenuation from the accumulation of dust on the PEC cells caused by micrometeorites pulverizing the lunar surface, coupled with the solar wind inducing an electrostatic charge in the resulting dust. And of course dust storms are relatively frequent on Mars which could significantly degrade performance. To address this problem self cleaning coatings are suggested as a solution. Solar irradiance was also considered as it would be reduced at the orbit of Mars. It was concluded that the PEC performance could be significantly boosted with solar concentrators by a factor of 1000 enabling higher production rates and power densities, especially on Mars.

An added advantage for space-based application of this technology is the elements needed to construct PEC devices are readily available on these worlds obviating the need to transport them from Earth and thereby significantly reducing costs.

“…in-situ utilization of elements on both, the Moon and Mars, is feasible for the construction of PEC devices.”

The technology is ideal to augment the production of oxygen in environmentally controlled life support systems of habitats that may not initially be 100% closed and cannot easily be resupplied with consumables from Earth. A competing technology for oxygen production which was recently demonstrated on Mars is the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) which functions via solid oxide electrolysis of carbon dioxide. This process requires high temperatures and therefore, more energy presenting a challenge when increased production of oxygen will be required for large settlements. The author’s analysis show that the PEC devices are more energy efficient and can easily be scaled up.

“Oxygen production via unassisted PEC systems can … be carried out at room temperature … suitable to be housed in temperature controlled space habitats.”


* Authors of the Nature Communications article Assessment of the technological viability of photoelectrochemical devices for oxygen and fuel production on Moon and Mars: Byron Ross at the University of Warwick, UK; Sophia Haussener at Ecole Polytechnique Fédérale de Lausanne, Switerland; Katharina Brinkert, University of Bremen, Germany