Minerva Space Settlement and University of Space Exploration

Conceptual illustration of the Minerva Space Settlement in orbit around Jupiter’s moon Ganymede. Credits: Minerva Project Team

Space Settlement Progress typically features the latest advancements in technology that are enabling the settlement of space.  This post will be a little different.  When attending the International Space Development Conference last May I was impressed by a team of students from Highschool Colegiul National Andrei Saguna in Romania, who had conceived of a space settlement in orbit around Jupiter’s satellite Ganymede which they call Minerva.  The project was an entry in the National Space Societies’ Space Settlement Contest, and for which they won a second place award for 9th graders.  While admiring their poster I was approached by Maria Vasilescu, who proudly described their project and agreed to collaborate with me on this post. She spoke perfect English, shared marketing materials (key chains, buttons and bookmarks with QR codes linking to their website) and explained that the primary purpose of Minerva would be a deep space location for a University of Space Exploration.  I was intrigued by the concept and was struck by Maria and her teammates’ enthusiastic vision of humanity’s future in space.  I wanted to know more about what motivated this group of teenagers to come together and create such an imaginative project, as youths like them will be future pioneers on the High Frontier.  Maria agreed to coordinate with her team on an interview via email about Minerva.

The Minerva Project Team and their poster session at ISDC 2023, a second prize winner for 9th graders of the NSS Space Settlement Contest. Credits: Minerva Project Team: clockwise from lower right: Bodean Mircea-Sorin, Ana Radus, Andrei Ioan Prunea, Alexandra Nica, Alexandra Maria Nemes, Maria Vasilescu

SSP: How did the team come up with this Minerva concept?

Minerva: We took inspiration from our school which gave us a lot of opportunities to which we owe a lot and we wanted to build such a university in the final frontier.

SSP: You mentioned stumbling across some obstacles during your journey but sticking together by motivating each other.  Is this an experience you feel comfortable sharing?

Minerva: One of the hardest things was to think about all the aspects that go into making a space settlement as ninth graders, such as the form [Forum on the website], which was decided in the last week, or the economical part. But we managed to meet often and brainstorm to come up with better ideas.

SSP: You said that the project helped you discover your true selves. Can you explain how this came about?

Minerva: We developed ourselves and our passions and we found out what we like because it covers a broad area of subjects beyond science. We managed to see by which area we are drawn to and enjoy actually researching.

SSP: You’ve stated that one of the reasons for building Minerva is to invent new lifestyles different from those that exist on Earth. How do you envision lifestyles changing in space?

Minerva: The university can prepare you for life in space, which will be an important part in the humans’ future, therefore we don’t want to invent new lifestyles, but incorporate space in the ones that already exist.

SSP: You’ve proposed auctioning a Minerva NFT to fund your efforts and future experiments.  Would this be the sole source of financing for the project, and will it be sufficient?  What about simply charging tuition for the USE?

Minerva: Everything on our settlement is given and made by us for the people so they don’t need to have money to buy material things. And because we have worked to make almost everything renewable and green, the funds MinervaNFT will bring are more than sufficient for everything else. And as for tuition, we feel like putting students through an exam such as the one that defines their attendance to USE is stressful enough as it is. However, the students will need to pay for the transport from Earth to the settlement.

SSP: There does not appear to be any trade or economic activity on Minerva, only academic studies. Students may choose to return to Earth or stay on the space station after they complete their studies. If they stay, have you considered the possibility of graduates developing and marketing other industries such as software development, robotics, mining water from Ganymede as rocket fuel, intellectual property on life support systems, or many other potential industries that could arise from scientific innovation that would take place on a space settlement? Or would this be totally an academic institution?

Minerva: It is not a totally academic institution because we have two thirds of the ship which will be occupied by students that remained on the settlement. But here, you don’t need money, everything being provided by us, so people don’t work for money, they work to occupy time, for enjoyment. If they do develop other industries, it will be fully for the greater good of humanity and the future of our kind, not for money.

SSP: The location chosen for Minerva is very challenging from an engineering perspective.  Although Ganymede is not deep in Jupiter’s magnetosphere, and has its own magnetic field which could help mitigate exposure, the location will still have high levels of radiation if unprotected, which complicates the design because much more mass is needed to provide adequate shielding to be safe for humans.  In addition, travel times to Jupiter are quite long even with improved propulsion which you’ve indicated would be as high as four years for students wanting to make the journey.  Finally, solar energy at Jupiter’s remote distance from the sun requires that photovoltaic arrays be enormous to provide sufficient energy. A good compromise might be the asteroid Ceres, which is believed to be 25% water and does not have a magnetic field generating high radiation like what would be experienced at Jupiter.  Others have proposed this asteroid as a good destination for space settlement.  Why not locate the settlement in a more accessible and hospitable environment that might reduce costs? 

Minerva: The main reason we chose such a far away location is precisely because we want to explore as much as possible of the cosmos. It’s not that we don’t want a closer location, it’s just that we know very little about Jupiter and its surrounding moons and further and this university can offer humanity an opportunity to explore it and send the research back to Earth. At the same time, we have taken the radiation into consideration and just how today’s spaceships have protection against it, so how [sic] our settlement, but ten times more efficient.

SSP: The sources of power for Minerva include solar arrays and nuclear fission, but you excluded fusion energy because it is currently experimental.  By the time it will be technologically possible to travel to Jupiter and establish infrastructure that far out in the solar system, we will have developed fusion energy for use on Earth as well as in space.  The preliminary design work for a Direct Fusion Drive for rapid transit to the outer planets has been started by Princeton Satellite Systems and the Fusion Industry Association just came out with their third annual report stating that the industry has now attracted over $6 billion in investment.  When it is feasible to begin work on Minerva, fusion power sources will likely be available. Will you be updating your project plan as new technologies become available? 

Minerva: Of course, we are sure that many aspects of our settlement can be improved by future developments in science, engineering and many other fields. As much as possible, we will incorporate them into our settlement. As mentioned in our paper, when talking about technological advances that may happen, we have to keep up with innovation and incorporate them to help us fulfill every need when travelling to space.

SSP: You raised the concern that Earth is approaching a major crisis with population growth putting a strain on Earth’s vital resources.  You also said that the purpose of the space community is to sustain humanity if Earth’s environment became unfavorable for life.  In selecting the location of Minerva, when considering Mars and its orbital distance, you said that even though it fulfills most of your requirements “…the disadvantage of Mars its it proximity to Earth…” and it “…is too close to our planet in order for us to choose it as the proper placement for the spacecraft.”  Why must Minerva be distant from Earth if the planet is in crisis in the future and why isn’t the orbit of Mars, at 56 million kilometers, considered not far enough away?

Minerva: Mars wasn’t a viable option because, as we have stated before, the purpose of the USE is to gather information and scientific news that can only be found in the farther cosmos. We already know a lot about Mars and planets in close proximity to Earth, we want to venture further, discover and experiment with more than we already have.

SSP: Some surveys say that young people live in fear of the future due to climate change.  Many media outlets amplify this doom and gloom.  However, some economists point out that using the United Nation’s own data from the Intergovernmental Panel on Climate Change, with the predicted increase in temperature by the year 2100, global GDP will be reduced by only 4% to deal with climate related impacts.  Although it is clear that we should eventually reduce our dependance on fossil fuels this is not an existential threat.   Plus, technological innovation continues to improve efficiency in resource utilization, energy development and agriculture, enabling higher standards of living notwithstanding increasing population growth. 

The viewpoint that the Earth is in “crisis” is closely aligned with Elon Musk’s motivation, who believes it is urgent that we become a multiplanetary species, to have a “Plan B” in case of a planetwide catastrophe.  Jeff Bezos has a different perspective, that heavy industrial activity could be moved off world to preserve the Earth’s natural environment and to improve humanities’ standard of living though utilization of unlimited space resources.  

Gerard K. O’Neill saw the promise of space settlement as a way to solve Earth’s problems through the humanization of space.  He saw it as a way to end poverty for all humans, provide high-quality living space that would continue to grow robustly, to moderate population growth without war, famine, dictatorship or coercion; and to increase individual freedom.  Does your team share the same anxiety about the future as other young people: that life on Earth is doomed and therefore, we need to build Minvera as a sanctuary to preserve humanity?  Or do you see it as one among many options for space settlement to improve life on Earth and beyond, as outlined in O’Neill’s vision?

Minerva: We see Minerva as a place where people that are smart and passionate about space have a chance to make scientific discoveries that would be impossible to do on Earth. Aligned with Gerald O’Neil’s [sic] view, we believe that humans should expand into space whether it is as a Plan B or by harvesting resources from other planets or celestial objects. With the help of Minerva, the smartest children of their generation will be able to experience these scenarios and be closer to the future. We don’t see Minerva as a Plan B for humanity, students that have finished their 4 years being able to return to earth, but rather as a place where people can enjoy a stress free and enjoyable environment. Therefore Minerva is preparing smart youngsters to be able to take advantage of any of the two cases. If they choose to remain on Earth, the knowledge that they acquired while in the USE will definitely increase humanity’s survivability against the existential threats mentioned.

SSP: You’ve created a survey [what was earlier referred to as a “Form” and can be found at the “Forum” link on the Minerva website] for anyone to express their opinion about your project and the prospect of living in space.  Will you use this feedback to improve your project? 

Minerva: Maybe in the future, yes. We have encouraged people to complete the survey honestly and there’s always place for improvement for anything. And the second reason is to observe humanity’s view on such a settlement. In creating such a complex space settlement, you need to align your view with the society’s beliefs, them being the ones who will eventually populate it.

SSP: Does your team expect to remain engaged with the project as you progress in your education and after you eventually establish your careers here on Earth?

Minerva: It was certainly an experience we will treasure for a long time, but not everything has to be drawn out. I think this project took a lot of work and effort and we want to invest into something new, see this contest from as many angles as possible while we can. This project like no other can incorporate so many aspects of society from which you can discover your biggest passions. Talking to everyone in our group, we found that each one of us enjoyed a different part of the project and we believe that that was the key to our win. We were all doing something we are passionate about and therefore worked even harder for the final result. Now that we’ve learned what topics intrigue us, we can start doing even more work in that domain. We believe that this project is the perfect opportunity and will open numerous doors in any future career path. We strongly recommend this contest to anyone wondering whether they should put their effort into it or not.

Creating a Space Settlement Cambrian Explosion – Interview with Kent Nebergall

Credits: Kent Nebergall

I met Kent Nebergall during a cocktail reception at ISDC which took place May 27-29.  He chairs the Steering Committee for the Mars Society (MS) and gave a fascinating talk Sunday afternoon on Creating a Space Settlement Cambrian Explosion.  We had a wide-ranging discussion on some of his visions for space settlement and he agreed to collaborate on this post.  We’ll do a deep dive into some of the topics he covered in his talk, which is available on his website at MacroInvent.

In summary, he breaks down some of the key challenges of space settlement and proposes economic models for sustainable growth. His roadmap lays out a series of space settlement architectures starting with a variant of SpaceX Starship used as a building block for large rotating habitats and surface bases for the moon, Mars, and asteroids. Next, he presents his Eureka Mars Settlement design which was entered in the MS 2019 Mars Colony Design Contest addressing every technical challenge. Finally, an elegant system for para-terraforming Martian canyons in multi-layered habitats is proposed, “…with the goal of maximizing species diversity and migration beyond our finite world. We not only preserve and diversify species across biomes, but engineer new species for both artificial and exoplanetary habitats. This is an engine for creating technology and biological revolutions in sequence so that as each matures, a new generation is in place to keep driving expansion across the solar system and beyond.”

Here’s my interview with Kent conducted via email.  I hope you enjoy it!

SSP: You created a checklist of the required technologies needed to enable space settlement where each row is sorted by increasing necessity while the columns are sorted by greater isolation from Earth.

Credits: Kent Nebergall

Musk has started to crack the cheap access to space nut and large vehicle launch at upper left with Starship but we’re not there yet.  Given that Musk’s timelines always should be taken with a grain of salt, and the challenge of planetary protection (bottom of column 3) could potentially prevent Musk from obtaining a launch license for a crewed mission before scientists have a chance to robotically search for signs of life, what is your estimation of the probability that Humans will land on Mars by 2029, in accordance with your proposed timeline (see below)?

KN: Elon time is real, definitely.  My outside analysis implies that SpaceX is using Agile development systems borrowed from the software industry.  The benefit of Agile is that technological progress is as fast as humanly possible.  The bad news is that it largely ignores things that traditional management styles value, such as being able to predict the date something is really finished.  At any rate, my general conclusion is that anything Elon predicts will be off by 43 percent as a baseline, assuming no outside factors are involved.  Starship has slid more because the specifications kept changing, much as they did with Falcon Heavy.

We seem to be locked in on the early orbital design, which seems to be purely for getting Starlink 2 satellites in place and providing return on investment while getting the core flight systems refined. It doesn’t need solar panels, crew space, or the ability to stay on orbit more than a day. Crewed Starship may take another few years and use a smaller than expected cabin with a large payload bay. 2029 is the most recent year of a crewed Mars landing from Elon (as of March, 2022). If we allow for Elon Time, we could expect cargo in that launch window. I suspect one vehicle may try to return to prove out that flight range, like return to Earth from deep space. The first mission would largely be watching Optimus Prime robots setting up a farm of solar panels to make fuel for the return trip.

“The irony is that Elon could just pack the ship with Tesla humanoid robots for the first few missions…”

The planetary protection regulatory barrier is quite possible, yes. We just saw the regulatory findings for Bocca Chica. That requires several frivolous preconditions for flight, like writing an essay on historic monuments and accommodating ocelots, which haven’t been seen in the area in forty years. I doubt the capacity of political Simon Says playground games like has been exhausted yet.

What we’ve seen historically is that those who cannot compete will throw up regulatory and legal barriers. However, we’ve also seen that these efforts eventually burn out after a few years. This has been true with paddle wheel river ships, steam ships, railroads, and airlines. It’s playing out with Tesla and the big three domestic automakers now as well. Most of those tricks were already pulled with Falcon 9, so I think that path is largely burned through. I’m nearly certain they will try the planetary protection argument later. We have already seen with the ocelots that they are willing to protect absent species.

The irony is that Elon could just pack the ship with Tesla humanoid robots for the first few missions and build a base while running life searches in the area. The base could be built with nearly the same productivity as a human crew, and the cultural pressure to move humans into it would be quite high if no life is found in the meantime. It would be great marketing for the Tesla robots as well.

SSP: The table seems comprehensive and covers just about everything.  Has it changed or been updated in 18 years?  I noticed “Spacesuit Lifespan”.  Why is this a challenge for space settlement?

KN: The table is fairly solid in terms of subject matter, but I’ve started a project to rebuild it.  I only found out recently that NASA’s term for this is RIDGE (Radiation, Isolation, Distance, Gravity and Environment).  My slicing into 26 categories is more precise – literally an alphabet of categories.

First, if it were a true “periodic table” analog, it would transpose the columns.  But it’s much easier to fit in PowerPoint this way. Second, I have used this principle for other challenge sets and found interesting implications, so I may make a more advanced version in the future with far more depth. I’ll still use this for PowerPoint, though, because it can be read from the back row in under a minute. Third, each “challenge” is actually a family of challenges.  There are multiple health problems with microgravity, for example, but one root cause – the absence of gravity.  So, while each challenge in the table has many sub-factors, there is a single root cause and a solution that eliminates that cause also eliminates all sub-sets of problems.  If a solution cannot fix the root cause, than separate solutions are needed for each child challenge like bone loss.

Spacesuit lifespan for the ISS is an issue because the suits are often older than the station itself.  On the moon, the spacesuits picked up abrasive moon dust in the joints and could have eventually lost flexibility or pressure integrity if they’d been used much longer.  A Mars suit is in some ways easier because the soil is more weathered and therefore less abrasive. Space settlement hits a standstill if you can’t go outside.  Unfortunately, efforts to replace them have cost a billion dollars so far and have just been restarted for an even higher price tag.  It seems to be the classic example of doing as little progress as possible while spending as much money as possible.  There have been some great technologies developed but there has been no pressure to finish a completed suit.  As the old saying goes, “One day, you just have to just shoot the engineer and cut metal”.

At one point, SpaceX outright said, “We can do it.” But NASA showed no interest, and SpaceX apparently didn’t bid on the moon suit designs this time.  They have been converting the ascent suit from Dragon to one able to do spacewalks in the 1960’s Gemini sense for launch this year.  I wouldn’t be surprised if they develop a moon suit just because they can, and on their own dime.  It would be quite embarrassing for all involved, including SpaceX, if we had a 100 tonne payload moon lander capable of holding dozens of people, and not have a single suit capable of letting them leave the ship.

SSP: You mentioned orbital debris being a potential barrier for your plan’s LEO operations and you’ve come up with methods for shielding early orbital habitats, but they may not be effective against larger debris fragments.  The X-prize Foundation is considering an award for ideas to solve this problem and there are numerous startups on the verge of addressing the issue.  Such a solution would have to be implemented quickly and on a massive scale for your timeline to be achieved.  If orbital debris looks like it may still be a problem for larger orbital settlements until they can be established in higher orbits, could your plan be modified to perhaps include debris removal as an economic driver?  [SpaceX president and COO Gwynne Shotwell has suggested that Starship could be leveraged to help clean up LEO]

The problem must be sliced up, just as the other grand challenges are sliced up. We need several approaches at once.  First, refueling starship is a bit risky, and the risk rises with prolonged exposure to the debris hazard.  SpaceX originally wanted to launch the Mars vehicle, then refuel it on orbit over several tanker flights.  More recently, they are implying they would fly a tanker up, fill it with several other tankers, then refuel the Mars or Lunar vehicle in one go.  This makes a lot more sense.  A tanker or depot hit by debris would be a space junk hazard, but it wouldn’t cost lives or science hardware. 

We need to de-orbit the largest items, many of which are spent rocket stages.  SpaceX has offered to gobble them up with Starship, but that means a lot of delta V in terms of altitude, inclination, elliptical elements, and so on.  I could see a sort of penny jar approach where they drop off a satellite, then pick up an old one or two (the satellite and old rocket stage) before returning. Realistically, though, old rocket stages and satellites that haven’t vented every single tank (main and RCS [reaction control system]) will be hazardous to approach. 

It seems the best solution would be mass-produced mini-satellites with ion drive and electrodynamic tethers.  Each mini-sat would find a spent rocket stage or defunct satellite and add an electrodynamic tether to drag it down using Earth’s magnetic field while also powering an ion engine to assist in de-orbiting.  You would have to do a few at a time because the tethers themselves would become a hazard if we had thousands of them cutting through space like razor ribbons.

I could also see a spider robot that would grab larger satellites with propellant still on board, wrap them up like a spider wrapping a bug in silk, and then puncturing the tanks carefully to both refill itself and render the satellite inert.  It would then be safe to grab with a Starship or de-orbit with a drag or propellant system [Another concept for debris removal could be Bruce Damer’s SHEPHERD which we covered a year ago. Although originally conceived for asteroid capture, a pathfinder application could be satellite servicing/decommissioning]. 

We didn’t create the problem in a day, and we can’t solve it quickly either.  But we can take an approach of de-orbiting two tons for every ton launched once we have mass produced systems for doing so.  Maybe other launch providers can grab defunct satellites with their orbital launch stages before dragging them both into the Pacific.

That said, we can’t get every paint chip and bolt out of orbit this way.  We will hit a law of diminishing returns.  Anything below that line will require a technology to survive impacts.  The pykrete ice shield I proposed could be much smaller, such as just one hexagonal hangar big enough for 2-3 starships in LEO at a time.  Once refueled, the craft would go to the much safer L5 point or directly to the moon if that is the destination.  Keeping a ring at L5 would not require a massive ice shield or centrifuge habitat to be a useful waystation.  But those would be designed into it up front to give room for expansion. 

If we decided that a Mars mission had to wait for all the infrastructure I proposed, we’d be in the same trap that Von Braun would have fell into of wanting massive infrastructure before the first crewed lunar mission.  You need a balance of infrastructure and exploration to give both meaning.

 “We can democratize early if we give some participation method in the initial investments in time, technology, and financing.”

SSP: Musk says he needs 100s of starships to deliver millions of tons of materials to support large cities on Mars by mid-century (his timeline).  You’ve created a somewhat more reasonable timeline for Starship round trip logistics for this effort based on Hohmann transfer orbits and Mars orbital launch windows (i.e. every 2 years).

Credits: Kent Nebergall

What will be the economic driver for such an ambitious project besides Musk just “making it so”?  I saw later in your presentation that you proposed an initial sponsorship and collectables market followed by MarsSpec competitions.  How will these initiatives kickstart sufficient market enthusiasm to support such an enormous fleet of Starships?

KN: It’s a complex topic, and easily a book in itself.  To cut to the core of it, any major discovery or invention that is not democratized becomes historic or esoteric rather than revolutionary.  Technology revolutions do not take place in particle accelerators any more than music revolutions take place in symphony orchestra pits.  Things that don’t impact people constantly are simply curiosities.  Even many things taken for granted like GPS and running water are ignored, but they remain transformative.  When the furnace filter factory worker sends part of his month’s labor to Mars, we have space settlement.  We can democratize early if we give some participation method in the initial investments in time, technology, and financing.  But these waves will go from new and novel to basic and ignored rather quickly, and this is especially true if they succeed. 

Imagine being a medieval merchant and getting an opportunity to send a bag of grain on a voyage to Cabot or some other explorer.  In return you get a rock from the opposite side of the world, a certificate saying what you gave and authenticating what you got back, and a tiny bit of participation in the history of your era that you can share with your children.  A decade later, your son is working in a smelting plant in a port city and making hardware for houses in the new world.  In another decade your grandchildren are growing crops in Maryland.  It’s a bit like that.  Each wave will fund and create the industrial and skill base for the next wave before becoming culturally ubiquitous.  The last child has no interest in a rock from his Maryland backyard.  But to the grandfather living a generation or two beforehand, it may as well be from the moon. The wave of sponsorship, followed by specifications for space-rated products, followed by biological engineering in lower gravity worlds will each create benefits and enthusiasm back on Earth.  After that last wave, the economic ecosystem becomes permanently multi-planetary.

Everything else about space is a simple engineering problem.  Minds, trends, budgets, and so on are not so well behaved as atoms or heat, but they have a lot of history that we can use to model workable solutions. This is the one I came up with.

“The problem with any grand engineering venture is that every design looks good until it comes in contact with reality.” 

SSP: The Eureka Space Settlement concept features dual centrifuges providing artificial gravity equivalent to the Moon and Mars. 

Eureka settlement duel centrifuge facility providing lunar gravity on the inner ring and Mars gravity on the outer one.  Credits: Kent Nebergall

I like the idea of using variable gravity to study biological effects on plant and mammalian physiology, adapting species to be multi-planetary and prepping for settlements that will need gravity as we move out into the outer solar system, but this can be done more cheaply in LEO or in cislunar space as outlined earlier in your architecture.  Why not simplify the Eureka settlement by eliminating the centrifuge and going with normal Mars gravity? 

KN: The problem with any grand engineering venture is that every design looks good until it comes in contact with reality.  You can’t model every issue up front, and one of the hardest to work out without experience are multi-generational ecosystems.  If we build a $100 billion Mars city and the kids have birth defects, we have a huge liability issue and a city that will be turned over to robots or dust.

The advocates assume all will be fine, but they tend to downplay issues.  The critics assume all will go poorly, but they never want to venture past the status quo.  Reality will be a mixed bag of data points on a bell curve between the two with both unknown threats and opportunities waiting for discovery.  This unknown is a big reason for the enthusiasm to try in the first place.

I came up with the steelman methodology by taking all the criticisms and range of danger possibilities and cranking the bell curve values up a few sigma to the nasty side.  The idea is that if you can STILL make an affordable design that pays for itself when the universe is coming after you with a hammer, you probably will be fine when the bell curve is realized.  You should always have a back-down plan to have surface domes with no centrifuges, or simply use the centrifuges for pregnant mammals and trees that need to fight gravity to have enough limb strength to bear fruit.  That said, another beauty of this design is that a Pluto colony or asteroid colony will almost certainly need centrifuges for multigenerational life.  Prototyping it on Mars may be overkill for Mars, but perfect for Pluto or Enceladus. This makes it much easier for Mars settlers to think about colonizing the outer solar system.  Even the children of our dreams need dreams, after all. 

“A space outpost must bring materials to itself, so a system like that without surface outposts or asteroid mining is a dead end.” 

SSP: In the proposed first wave of the architecture, rotating settlements are created from Starship building blocks in high orbit to create “…deep space industrial outposts in the O’Neill tradition with a thousand inhabitants each. On the lunar and Martian surface, we simply take a slice of the ring architecture with starships inside as an outpost.”  With the amount of investment needed to build the infrastructure to transport materials and people for large settlements on Mars, and given that the biggest grand challenge on your chart is reproduction (which may not be possible in less than Earth’s gravity), why wouldn’t it make more sense to focus efforts on building larger 1G rotating free space settlements where we know having children is possible?

KN: It’s not so much a roadmap of first this structure here, then that one there.  It’s a draft set of compatible building standards for everywhere.  Think about the standard sizes for bricks, pipes, and wiring and how entire continents use them interchangeably over a hundred years or more.  My goal was to lay out what the maximum amount of infrastructure would look like with the minimum number of parts.

There is a false dichotomy between structures like space stations made entirely from material from Earth, and local materials formed with 3D printers that can do everything with complete reliability.  Both are impractical extremes, and to some degree strawman designs.  Importing everything is prohibitively expensive even with Starship.  Conversely, creating structures from random conglomerates of whatever material is at the landing site will be too brittle. By proposing bags that can be made of basalt cloth but that will initially come from Earth, I’m bridging the two extremes.  They can be filled with dust, water, sand, or whatever is fine grained enough and can be either sintered or cemented in place.  Such structures don’t have to be aligned with absolute precision and can follow soft contours or whatever is needed.  You also don’t need four meters of shielding for cosmic rays if you augment it with magnets. They can be scaled in layers or levels as needed, just like bricks or two by four boards are in homes.

A space outpost must bring materials to itself, so a system like that without surface outposts or asteroid mining is a dead end. 

Centrifuges for surface settlements are a bit awkward, to be sure.  A train system that keeps the floor below you when spinning or de-spinning is a better system at first.  Eureka was mainly done with fixed pitch decks just to show that the scale of a centrifuge for a large torus L5 ring could be done on a surface with some clever engineering.  My original design goal was to make the cars, car beds, rails, and buildings swappable without stopping the ring rotation.  In the same way, the pressure shell has inner and outer walls that can in theory be replaced while the other keeps pressure.  It’s probably not necessary, but the goal is to remove all design barriers early in the thought process so that future engineers aren’t painted into corners.

SSP: After the first settlements are established on Mars, you suggest starting to adapt the Mars environment to Earth-like conditions through “para-terraforming” small parts of the planet such as the Hebes Chasma, a canyon the size of Lake Erie just north of Valles Marineris.  This feature has the advantage of being right on the equator and closed at both ends so that kilometer sized arch structures could enclose the valley to warm the local environment with many Eureka settlements below.

Top: Artist concept of kilometer scale arches built above space settlements and enclosing a Martian canyon to provide a para-terraformed environment.  Bottom: Magnificent view from below depicting these domes at cloud level on a typical summer day. Credits: Kent Nebergall / Aarya Singh

Planetary protection was mentioned as one of the grand challenges to be overcome.  Some space scientists are advocating for robotic missions to answer the question of whether life existed (or still exists) on Mars before humans reach Mars.  No such missions are planned prior to Musk’s timeline for putting humans on Mars at the end of this decade.  Are you assuming that by the time humans are ready for para-terraforming that the question of life on Mars will be answered? 

KN: We would certainly know if active, widespread, indigenous life was an issue by the time of building canyon settlements the size of Lake Erie.  Even isolated pockets would leave fossil traces in broader zones.

The bigger question is that of whether or not it is possible to settle Mars if there is a risk of crossing into a local biome accidently.  Eureka is built entirely on the surface, so it doesn’t cross the sterilized surface soils if it doesn’t have to.  We should be able to mine from Mars with sterile equipment and be able to sterilize further after robotic extraction. We can extract water ice, volcanic rock, and surface dust and build the entire settlement from those basic materials. We can avoid sedimentary materials until we are confident they are not biologically active. 

I suspect any life on Mars is from Earth, and brought by meteors.  The cross-traffic of meteors throughout the solar system may mean bacterial and possibly slightly more complex life all over the solar system from the late bombardments of Earth.  We should consider this no more exotic than breathing in Australia or swimming in the ocean.  Microbes adapted for those environments would not be adapted to be pathogenic because why spend billions of generations preparing for a food source that may never arrive?  We would have a bigger problem with random toxins that hadn’t leached out or reacted to life billions of years ago than with life itself.  I respect the work of those who want sterile capsules of pristine soil captured by the current Mars rover prior to human arrival.  That certainly makes sense.  I like Carol Stoker’s Icebreaker mission concept. I think NASA and universities would be smart to work with SpaceX on simple rack-mount instrumentation that could be flown to planetary destinations en masse and serviced by Optimus Prime Tesla robots. 

“My goal is to build the next generation of the quiet heroes of the dinner table.  And certainly a few of those will be leaders too.”

SSP: You’re writing a book about creating an inventor mindset to enable a million “mini-Musks” – people who are not necessarily rich, but who shake up the world in constructive and innovative ways.  Tell us more about this philosophy.

KN: The core concept is that if you could get a thousand people to do a hundredth of what Elon has accomplished, it would be a tenfold increase in what we’ve seen in terms of his contribution to technology.  That’s not a very big ask individually, even if it’s more garage labs than factories for now.  I looked deeply into what Elon Musk does and what other inventors like him have done.  I’ve looked at technology revolutions and what key things spark the massive growth waves of innovation.  Obviously, there are intersections between the two. 

I’m writing a short book this summer to document Elon’s methodologies in an approachable and comprehensive reference.  If it attracts enough interest, I can take that core module into different directions.  One is digging more into how the mind invents.  Another is breaking down how technology revolutions work.  A third is all this work on space settlement. I’ve also come up with intellectual property around the root of these concepts that would be valuable software and services.  I guess we’ll see what reaction the Elon book gets and see where that goes.  It’s a bit heartbreaking to see millions spent on NFTs and other random “stupid money” projects when I’m coming up with concepts for trillion-dollar companies as a hobby.

While we talk a lot about Musk, there are thousands of people who work just behind the spotlight.  My father was a production test pilot who put his life on the line to ensure that bombers were flyable for national security, and that the technology that became the commercial jet airliner a decade later would be safe for billions of travelers.  He worked with some historic figures of aviation, and his dinner stories were amazing.  The Mars Society gave me a way to repeat a little of this history for myself in this dawn of the Mars Age. 

Technology revolutions may celebrate a few leaders.  But without thousands of talented people several feet behind these inventors, they are little more than curiosities – Di Vinci notebooks or Antikythera mechanisms.  My goal is to build the next generation of the quiet heroes of the dinner table.  And certainly a few of those will be leaders too.  That is my hope.  To fill the diaries of pioneers that give permanent cultural bedrock to the accomplishments of people like Elon.  Otherwise, even a moon landing is a short story written in water.


Don’t miss Kent’s appearance on The Space Show coming up on Sunday July 10 where you can call in and ask him in person your own questions about these and other visions for space settlement.

Starship changes the space settlement paradigm

Artist rendering of an earlier version of Starship (formerly BFR, Interplanetary Transport System) approaching Mars. Credits: SpaceX

A mission architecture for Starship is described in a preprint open access article published online December 2 to be released in the next issue of the New Space Journal. The paper lays out a proposed strategy for using the yet to be validated SpaceX reusable spacecraft to establish a self sustaining colony on Mars. The authors* are a mix of space practitioners from NASA, the space industry and academia. No doubt Elon Musk may be thinking along these lines as he lays his company’s plans to assist the human race in becoming a multi-planet species.

Starship is a game changer. It is being designed from the start to deposit massive payloads on The Red Planet. It will be capable of delivering 100 metric tons of equipment and/or crew to the Martian surface, and after refueling from locally sourced resources, returning to Earth. This capability will not only enable extensive operations on Mars, it will open up the inner solar system to affordable and sustainable colonization.

Some of the assumptions posited for the mission architecture are based on Musk’s own vision for his company’s flagship space vehicle as articulated in the New Space Journal back in 2017, namely that two uncrewed Starships would initially be sent to the surface of Mars with equipment to prepare for a sustainable human presence.

“These first uncrewed Starships should remain on the surface of Mars indefinitely and serve as infrastructure for building up the human base.”

The initial landing sites will be selected based on where the water is. The priority will be finding and characterizing ice deposits so that humans will eventually be able to locally source water for life support and to produce fuel for the trip home. The automated payloads of these initial missions will be mobile platforms similar in design to equipment planned for upcoming robotic missions to the Moon in the next couple of years. One such spacecraft, the Volatiles Investigating Polar Exploration Rover (VIPER) is discussed with its suite of instruments that will be used to assess the composition, distribution, and depth of subsurface ice to inform follow-on ISRU operations.

“The use of water ice for ISRU has been determined as a critical feature of sustainability for a long-term human presence on Mars.”

VIPER Searches for Water Ice on the Moon
Conceptual depiction of the NASA VIPER rover planned for delivery to the Moon’s south pole in late 2023. A mobile platform with a similar suite of instruments based on this design could be launched to Mars aboard Starship. Credits: NASA

To harvest water from subsurface ice the authors suggest using proven technology such as a Rodriguez Well (Rodwell). In use since 1995, a Rodwell has been providing drinking water for the U.S. research station in Antarctica. The U.S. Army Engineer Research and Development Center’s (ERDC) Cold Region Research and Engineering Laboratory (CRREL)  has been working with NASA to prove the technology for use in space in advance of a human outpost on Mars.

Diagram depicting how a Rodriquez Well works. Credits: U.S. Army Engineer Research and Development Center

“Rodwell systems are robust and still in routine use in polar regions on Earth.”

The next order of business is power generation. The authors suggest using solar power as a first choice because the technology readiness level is the most mature at this time. Autonomous deployment of a photovoltaic solar array would be carried out on the initial uncrewed missions. But due to frequent dust storms that could diminish the array reliability, nuclear power may be a more appropriate long term solution once space based nuclear power is proven. NASA’s Glenn Research center is working on Fission Surface Power with plans for a lunar Technology Demonstration Mission in the near future. A solid core nuclear reactor is also an option as the technology is well understood.

These initial missions will robotically assess the Martian environment at the landing sites to inform designs of subsequent equipment to be delivered by crewed Starship missions in future launch windows occurring every 26 months. Weather monitoring will be performed as well as measurements of radiation levels and geomorphology to inform designs of habitats and trafficability. Remotely controlled experiments on hydroponics will also be performed to understand how to produce food. Testing will be needed on excavation, drilling, and construction methods to provide data on how infrastructure for a permanent colony will be robustly designed.

Starship’s ample payload capacity will allow prepositioning of supplies of food and water to support human missions before self sustaining ISRU and agriculture can be established. Communication equipment will be deployed and landing sites prepared for the arrival of people. Much of these activities will be tested on the Moon ahead of a Mars mission.

Production of methane and oxygen in situ on Mars will enable refueling of Starship for the trip home, as envisioned in 1990 by Robert Zubrin and David Baker with their Mars Direct mission architecture. Zubrin’s Pioneer Astronautics may even play a role through provision of equipment for ISRU as they are already working on hardware that could be tested on the Moon soon. One could envision a partnership between Zubrin and Musk as their organizations have common visions, and Zubrin has written about the transformative potential of Starship. When people arrive on Starship during a subsequent launch window after the placement of uncrewed vehicles, further testing of ISRU and life support equipment will be performed with humans in the loop to validate these technologies that will enable Mars settlements to sustain themselves.

If Musk is successful in establishing a permanent self-sustaining colony on Mars will it be a true settlement? The National Space Society in their definition says that a space settlement “..includes where families live on a permanent basis, and…with the goal of becoming…biologically self-sustaining…”, i.e. capable of human reproduction. The definition is agnostic as to if the settlement is in space or on a planetary surface. Musk wants to established cities on the planet housing millions of people by mid century. But does this make sense if settlers can’t have healthy children in the lower gravity of Mars? SSP explored this question in a recent post. Hopefully, once Starship becomes operational, an artificial gravity research facility in LEO will be high on Musk’s priority list to answer this question before he gets too far down the Martian urban planning roadmap. Would he ever consider a change in space settlement strategy in favor of O’Neill type free space colonies? Starship could certainly help facilitate the realization of that vision.

If all goes according to plan, SpaceX will attempt the first orbital flight of a Starship prototype sometime next year, which also happens to be when the next launch window opens up for trips to Mars. Obviously, nothing in rocket development goes according to plan, so the initial flight ready design is at least a year away optimistically. And we know Musk’s timelines are notoriously aspirational. As ambitious as Musk is in driving his company toward the goal of colonizing Mars, it seems unlikely that an initial uncrewed mission with all its flight ready automated hardware as described above could be ready by the next launch window in 2024. But what about 2026? NASA’s current plans for return to the Moon call for a human rated version of Starship as a lunar lander “…no earlier then 2025”. However, Japanese billionaire Yusaku Maezawathe’s Dear Moon mission sending 8 crew members around Luna with a crewed Starship is still planned for 2023. A lot of details are yet to be worked out and we still have not covered the topic of Planetary Protection nor the granting of a launch license to SpaceX by the FAA, but could a Starship human mission to Mars take place in 2028? Let me know what you think.

“The SpaceX Starship vehicle fundamentally changes the paradigm for human exploration of space and enables humans to develop into a multi-planet species.”

* Authors of Mission Architecture Using the SpaceX Starship Vehicle to Enable a Sustained Human Presence on Mars Jennifer L. Heldmann, Margarita M. Marinova, Darlene S.S. Lim, David Wilson, Peter Carrato, Keith Kennedy, Ann Esbeck, Tony Anthony Colaprete, Rick C. Elphic, Janine Captain, Kris Zacny, Leo Stolov, Boleslaw Mellerowicz, Joseph Palmowski, Ali M. Bramson, Nathaniel Putzig, Gareth Morgan, Hanna Sizemore, and Josh Coyan

Reproduction off Earth and its implications for space settlement

Launch of the Space Shuttle Atlantis (STS-66) on November 3, 1994. The mission carried an experiment called NIH.Rodent 1, the first of only two study’s to date on rats launched at mid-pregnancy and landed close to full term to study the effects of microgravity on reproduction. Credits: NASA

In a MDPI Journal Life paper, Alexandra Proshchina and a team* of Russian researchers summarize the research that has been performed thus far on reproduction of invertebrates in space. As mentioned in the article, the only data we have on mammalian reproduction in microgravity since the dawn of the space age is from two experiments carried out over 26 years ago. The studies looked at pregnant rats launched aboard the Space Shuttle on missions STS-66 and STS-70 in 1994 and 1995 respectively, and there have never been any births of mammals in space. This huge knowledge gap on reproduction in space is problematic for human space settlement. Yet Elon Musk, The Mars Society, and other groups are charging ahead with plans for cities on Mars. What if we discover that humans cannot have healthy babies in 0.38g? SSP has covered the quest for determining the gravity prescription before looking at JAXA’s effort to at least start experimenting with artificial gravity in space, albeit on adult mammals (mice). We are still waiting for JAXA’s published results of 1/6g experiments carried out in 2019.

The data from the Space Shuttle program only looked at part of the gestation period (after 9 days) and only in microgravity. The results did not bode well for reproduction in space. Some findings “…clearly indicate that microgravity, and possibly other nonspecific effects of spaceflight, can alter the normal development of the brain itself.”

Histological cross section through a representative rat brain from NIH.Rodent 1 experiment from STS-66. Left side (a) is low magnification and right side (b-d) are high magnification. Red arrows show areas of neurodegeneration. 1 – Nasal cavity, 2 – olfactory nerve, 3 – olfactory bulb, 4 – eye, 5 – cortex telencephali, 6 – hippocampus, 7 – fourth ventricle, 8 – cerebellum. Credits: Alexandra Proshchina et al.*

So we have this one piece of data for reproduction in microgravity and nothing in higher gravitational fields except what we know here on Earth in 1g.

Would partial gravity like on the Moon or Mars be sufficient for normal fetal development in rats (or mammals in general, especially humans) during the full gestation period? If problems are identified could it be extrapolated to human reproduction? The fact that homo sapiens and their ancestors evolved on Earth in 1g for hundreds of thousands of years is a big red flag for future space colonists that hope to settle on the surface of planetary bodies and have children.

We don’t know how lower gravity conditions could affect embryonic cell growth. How would the changes in surface tension and embryo cell adhesion be altered in these environments? We have very little data on cellular mechanisms and embryonic alterations that lower gravity may induce that could affect fetal development.

“There are also many other questions to be answered about vertebrate development under space flight conditions.”

A recent report on giving birth in space by SpaceTech Analytics looks at many of the factors that need to be considered for human reproduction off Earth. Most problems could be potentially mitigated through engineering solutions such as radiation protection, medical innovations tailored for space use, life support technology, etc. In this entire presentation the authors gave very little consideration to partial gravity affects on human embryos and child birth. One slide (number 70) out of 85 discusses these issues.

It is clear that more and longer term experiments will be necessary to determine how partial gravity affects the reproduction and development of mammals before humans settle space. Some researchers are actually considering genetic modification to allow healthy reproduction in space, and the ethical considerations associated with this course of action. Obviously, such a drastic methods would come only if there was no other alternative. One would think that building O’Neill type habitats rotating to produce 1g of artificial gravity would be preferable to such extreme measures.

Clearly, we need a space based artificial gravity laboratory to carry out ethical clinical studies on the gravity prescription for human reproduction, starting with rodents and other lower organisms. SSP recently covered a kilometer long version of such a facility that could be deployed in a single Falcon Heavy launch. And don’t forget Joe Carroll’s proposal for a LEO partial gravity test facility. Doesn’t it make sense to invest in such a facility and do the proper research before (or at least in parallel to) detailed engineering studies of colonies on the Moon or Mars intended for long term settlement? This research could inform decision making on where we will eventually establish permanent space settlements: on the surface of smaller worlds or in free space settlements envisioned by Gerard K. O’Neill. Elon Musk may want to consider such a facility before he gets too far down the road to establishing cities on Mars.


* Authors of Reproduction and the Early Development of Vertebrates in Space: Problems, Results, Opportunities: Alexandra Proshchina, Victoria Gulimova, Anastasia Kharlamova, Yuliya Krivova, Nadezhda Besova, Rustam Berdiev and Sergey Saveliev.

Coming soon: the $10M orbital condominium

Living space in a Kalpana orbital space settlement. Credits: Bryan Versteeg

Kasper Kubica presents an optimistic business case for space tenants moving in (er, up) to deluxe condominiums orbiting the Earth within 10 years. Initially for the ultra rich, the price tag is comparable to high end real estate currently on the market. Of course the devil is in the details, so lets dive in.

In a post on Medium, Kubica uses the rotating habitat Kalpana as an illustrative example of his “Spacelife Direct” approach for an orbital settlement spinning to create 1G of artificial gravity and hosting north of 400 condominiums in LEO. Such a facility would be shielded from radiation by Earth’s magnetosphere if it were located in low equatorial orbit and therefore could be constructed with less shielding. This results in a significant reduction of mass driving costs way down. Running the numbers on this scenario opens up exciting possibilities with the amazing capabilities of Elon Musk’s Starship currently under development by SpaceX.

Using the scaled down Kalpana Two version as discussed in Tom Marotta and Al Globus’ book, The High Frontier, an Easier Way, the cylindrical habitat is sized at just over 100 meters in diameter and the same in length, weighing in at 16, 800 metric tons. Kubica estimates that it would take 140 launches to loft the required mass to LEO. Assuming costs keep coming down as Starship launch cadence increases (a safe bet), at $10M/launch the cost of just the materials to LEO would be $1.4B. Of course there are many more expenses associated with design, development and fabrication, not to mention insurance of such an orbital condo complex. For the sake of argument Kubica triples that figure arriving at a total price tag of $4.2B.

But would there be a market for real estate in LEO? Kubica provides comparable examples of skyscrapers with similar costs and over 200 condominiums recently selling for over $10M in Manhattan.

“The clamor for earthside luxury condos is massive and growing. Orbital condos — representing an exclusive experience far beyond that available to anyone on earth — could generate astronomical demand.”

With the economics of Starship opening up limitless possibilities, Kubica lays out a roadmap over the next 10 years to realize the Spacelife Direct opportunity. First would come financing the venture though a team of visionary entrepreneurs and investors (are you listening Dylan Taylor?). Design and development would come next including the robotic systems that would be required for assembly in space. Laying the groundwork for this infrastructure may be completed soon by Orbital Assembly Corporation which could potentially be leveraged as a Spacelife Direct supplier. To keep labor costs down much of the facility would be fabricated on Earth in launchable modules that would be assembled in orbit. The final stages would activate life support systems and finish out the interiors for the occupants to begin moving in.

So what about the rest of us? As history has shown in the aerospace industry at the beginning of the last century and we see unfolding in the space tourism market today, the rich help pave the way so that mass production and economies of scale will drive down costs eventually making space settlement affordable for the masses.

“We don’t want to live in space because it’s an economic necessity, we want to live in space because we are explorers and adventurers, and space is humanity’s next frontier!”