Artist depiction of Starship on the lunar surface returning astronauts to the Moon as part of NASA’s Artemis Program. Credits: SpaceX
What will be the impact on the direction of U.S. space policy should SpaceX successfully demonstrate an orbital flight of Starship? Doug Plata, President and Founder of the Space Development Network believes that when Starship achieves orbit, policy makers should “…place Starship at the center of the country’s human spaceflight program…”. In an article in The Space Review he makes the case that if successful in its efforts, SpaceX may be edging us closer to a tipping point on deciding which path to take for the country’s human rated launch vehicle: Space Launch System (SLS) or Starship? This question is accentuated by recent news reports of yet another delay in the Artemis 1 uncrewed test flight of SLS which Ars Technica reports may not launch until the summer of 2022…assuming everything goes perfectly. Meanwhile, SpaceX continues its development of Starship at a breakneck pace, while simultaneously building the manufacturing infrastructure to “…crank them out by the hundreds”, says Plata. With the delay of Artemis 1, it is possible that SpaceX will demonstrate the first orbital launch of Starship before NASA’s first launch of SLS.
NASA has already selected SpaceX to return astronauts to the Moon via Starship as the Human Landing System for the Artemis program, although work has stalled on the contract due to Blue Origin’s lawsuit. But with a reusable Starship at a fraction of the cost, comparable heavy lift capability and a much higher flight rate, how long can SLS last? A case could be made for keeping SLS until SpaceX’s Super Heavy booster is human rated and Starship can be reliably shown to reenter the Earth’s atmosphere and land safely. But this won’t be long given Elon Musk’s aggressive timelines. Will it continue to make sense to launch astronauts on SLS/Orion, transfer them to Starship in lunar orbit and descend to the surface of the Moon when the the whole mission could be accomplished without SLS at a fraction of the cost?
“At some point, it will be obvious that SLS is an unnecessarily expensive alternative to Starship”
With Starship’s anticipated payload capabilities of delivery of 100s of tons and large crews to the lunar surface, and recent advances in inflatable technology, a habitat with a footprint of about 21,000 sq. ft. is within reach. Plata believes that the billions of dollars slated for SLS would be better spent contracting with SpaceX for delivery of inflatables and their supporting infrastructure to the lunar surface. This could lead to a large international lunar base which may eventually become a permanent settlement.
Conceptual illustration of InstaBase – a fully inflatable lunar base capable of supporting an initial crew of eight. Credits: The Space Development Network via The Space Review
“But there is an important historic significance to Starship as well…the real historic prize to be seized is the establishment of humanity’s first foothold off Earth.”
Conceptual rendering of TransAstra Honey Bee Optical Mining Vehicle designed to harvest water from near-Earth asteroids: Credits: TransAstra Corporation
Advocates for mining the Moon and asteroids for resources to support a space based economy are split on where to get started. Should we mine the Moon’s polar regions or would near-Earth asteroids (NEAs) be easier to access?
Joel Sercel, founder and CEO of TransAstra Corporation, is positioning his company to be the provider of gas stations for the coming cislunar economy. In a presentation on asteroid mining to the 2020 Free Market Forum he makes the case (about 10 minutes into the talk) that from an energy perspective in terms of delta V, NEAs located in roughly the same orbital plane as the Earth’s orbit may be easier to access for mining volatiles and rare Earth elements.
Scott Dorrington of the University of New South Wales discusses an architecture of a near-Earth asteroid mining industry in a paper from the proceedings of the 67th International Astronautical Congress. He models a transportation network of various orbits in cislunar space for an economy based on asteroid water-ice as the primary commodity. The network is composed of mining spacecraft, processing plants, and space tugs moving materials between these orbits to service customers in geostationary orbit.
Illustration depicting the layout of a transportation network in an asteroid mining industry in cislunar space. Credits: Scott Dorrington
On the other side of the argument, Kevin Cannon of the Colorado School of Mines in a post on his blog Planetary Intelligence lays out the case for the Moon being the best first choice. All of the useful elements available on asteroids are present on the Moon, and in some cases they are easier to access in terms of concentrated ore deposits. Although delta V requirements are higher to lift materials off the Moon, its much closer to where its needed in a cislunar economy. Trips out to a NEA would take a long time with current propulsion systems. In addition, he thinks mining NEAs would be an “operational nightmare” as most of these bodies are loose rubble piles of rocks and pebbles with irregular surfaces and very low gravity. This makes it hard to “land” on the asteroid, or difficult to capture and manipulate them. In an email I asked him if he was aware of SHEPHERD, a concept for gentle asteroid retrieval with a gas-filled enclosure which SSP covered in a previous post, but he had not heard of it. TransAstra’s Queen Bee asteroid mining spacecraft has a well thought out capture mechanism as well, although this concept like SHEPHERD are currently at very low technology readiness levels.
SHEPHERD-Fuel variant harvesting ice from a NEA and condensing it into liquid water in storage tanks, then subsequent separation into hydrogen and oxygen (top). These tanks become the fuel source for a self-propelling tanker block (bottom) which can be delivered to a refueling rendezvous point in cislunar space. Credits: Concept depicted by: Bruce Damer and Ryan Norkus with key design partnership from Peter Jenniskens and Julian Nott
Cannon also makes the point that there is very little mass in the accessible NEAs when compared to the abundance of elements on the Moon.
“There’s more than enough material for near-term needs on the Moon too, and it’s far closer and easier to operate on.”
Finally, he believes that the Moon would be a better stepping stone to mining the asteroids then NEAs would be. This is because most of the mass in the asteroid belt is located in the largest bodies Ceres and Vesta. Operations for mining on these worlds would be more akin to activities on the Moon then on near-Earth asteroids.
Image of Vesta taken from the NASA Dawn spacecraft. Credit: NASA/JPL
What about moving a NEA to cislunar space as proposed by NASA under the Obama Administration with the Asteroid Redirect Mission? Paul Sutter, an astrophysicist at SUNY Stony Brook and the Flatiron Institute, investigates this scenario and suggests that at least the argument for these asteroids being too far away might be mitigated by this approach, although it would take a long time to retrieve them using solar electric propulsion, as recommended in the article. The trip time might be reduced with advanced propulsion such as nuclear thermal rockets currently under investigation by NASA.
Conceptual illustration of TransAstra’s Sun Flower™ power towers collecting solar energy above a permanently shadowed region on the Moon to provide power for ice mining operations. Credits: TransAstra Corp.
Update 28 August 2021: Take a deep dive into TransAstra’s future plans with Joel Sercel interviewed by Peter Garretson, Senior Fellow in Defense Studies at the American Foreign Policy Council podcast Space Strategy.
Image of Lunar Transporter (L-Tran) with Lunar Regolith Excavator (L-Rex) stored on board as they roll down a ramp from a lunar lander. Credits: screen capture from Redwire Space animation. All images below are so credited.
NASA has just announced the winners of the Breaking the Ice Lunar Challenge, an incentive program for companies to investigate new approaches to ISRU for excavating icy regolith from the Moon’s polar regions. The agency will be awarding half a million dollars in cash prizes and Redwire Space headquartered in Jacksonville, Florida won first prize scoring $125,000 for its elegantly designed two rover lunar excavation system. The criteria used by NASA to select the winners was based on maximum water delivery, minimum energy use, and lowest-mass equipment.
Upon delivery by a lunar lander near a shadowed crater in the Moon’s south polar region, a multipurpose Lunar Transporter (L-Tran) carrying a Lunar Regolith Excavator (L-Rex) rolls down a ramp to begin operations on the surface. The rover transports the excavator to the target area where icy regolith has been discovered.
Image of L-Rex driving off of L-Tran
The L-Rex then drives off the L-Tran to start collecting regolith in rotating cylindrical drums on the front and back of the vehicle.
L-Rex collecting lunar regolith in fore and aft collection drumsL-Rex loading regolith into L-Tran for transport back to processing station
When the drums are full, L-Rex returns to the rover and deposits its load in L-Tran’s storage bed. L-Rex repeats this process over many trips until L-Tran is loaded to capacity at which point the rover returns to a processing facility to separate the water from the regolith.
L-Tran dumping a load of regolith into a hopper at a processing facilityAfter regolith beneficiation the separated frozen water ice is loaded into L-Tran for transport to secondary processing plant
Upon separation into purified frozen ice, L-Tran is once again loaded up with the product for transport to a station for storage or perhaps, further processing. No further details were provided but the final process is presumed to be electrolysis of the water into useful end products such as H2 and O2 for rocket fuel or life support uses, plus simply storage as drinking water for human habitation.
L-Tran loading water ice into hopper for final processing into end products or simply storage
The second place prize of $75,000 was awarded to the Colorado School of Mines in Golden, Colorado for its Lunar Ice Digging System (LIDs). The LIDS proposal has three rovers – an excavator, regolith hauler, and water hauler each of which would be teleoperated from a nearby lunar surface habitat.
Austere Engineering of Littleton, Colorado won the $50,000 third place prize for its Grading and Rotating for Water Located in Excavated Regolith (GROWLER) system. The system weighs slightly more then a school bus tipping the scales at an estimated mass of 12 metric tons.
A second phase of the challenge, if approved, could move the proposals into hardware development and a future demonstration mission toward eventual support of lunar habitats and a cislunar economy.
Checkout Redwire’s animation of their lunar excavation system:
Animation from Redwire Space’s Breaking the Ice Lunar Challenge proposal. Credits: Redwire Space
Conceptual depiction of the Pinwheel Magma Reactor on a planetary surface in the foreground and in free space on a tether as shown in the inset. Credits: Kevin Cannon
How can space settlers harness useful resources that have not been concentrated into ore bodies like what takes place via geologic process on Earth over eons of time? Could we artificially speed up the process using synthetic geology? Kevin Cannon, a planetary geologist at the Colorado School of Mines (CSM), thinks it might be possible to unlock the periodic table in space to access a treasure trove of materials with an invention he calls the Pinwheel Magma Reactor. He has submitted a NASA Innovative Advanced Concepts proposal for the concept. The device is a essentially a centrifuge sitting on a planetary surface with a solar furnace reaction chamber spun at the end of its axis. In space, a free flying system could be connected by tether.
PMR chambers are positioned at the end of the axis of a centrifuge. Credits: Kevin Cannon
In a Twitter thread Cannon sets the table with a basic geology lesson explaining why mining on Earth is so different from what we will need in space. The Earth’s dynamic crustal processes, driven by fluid flow and plate tectonics over millions of years, exhibit a very different geology then that under which the Moon, Mars and asteroids evolved. The critical minerals that could be useful to support life and a thriving economy in space settlements are present in far lower concentrations in space then on Earth.
Current plans for ISRU infrastructure on the Moon and asteroids are only targeting a small set of elements like hydrogen, oxygen, carbon, silicon and iron (below, left).
Illustration of the periodic table showing currently targeted elements for ISRU on the left. On the right, the most mined elements on Earth (colored gold) and critical elements (orange) useful for an advanced society. Credits: Kevin Cannon
But an advanced society expanding out into the solar system would benefit from many critical minerals (above, right) that are not easily accessible because of their far lower concentrations. For example, energy production will need uranium and thorium, energy storage systems require lithium and electronics manufacturing is dependent on rare earths. So how to unlock the periodic table for these critical materials?
If we are to live off the land by harvesting useful materials to build and sustain space settlements we’ll need a totally revolutionary mining process. The PMR was designed with this in mind. The procedure begins by loading unprepared rocks or regolith into the chamber followed by heating via a solar furnace. Next, the chamber is spun up in the centrifuge where super gravity concentrates the desired minerals. Cannon believes that the PMR could also be used to extract water from regolith on the moon or asteroids.
“If hydrated asteroid material or icy regolith are put in at low temperatures, they’ll be separated by super-gravity and can be siphoned off.”
Of course the technology needs to be validated and flight hardware developed to determine if the PMR can be a tool to speed up the geological processes to concentrate useful materials for humans, who can then use them to synthetically propagate life in space. Cannon sums it up:
“Obviously a lot of work to be done to prove out the concept. But I think that a process flow of synthetic geology -> synthetic biology is the way to solve the concentration problem in space and enrich any element we want from the periodic table.”
Conceptual illustration looking up the length of a Moon Town residential habitat built in a trench going down the crater wall. Plants cover its roof, walls, and foundation. Credits: Kim Holder, CC-BY 4.0. NOTE: all images are similarly credited
SSP has posted about Moonwards in the past. Kim Holder, creator of the realistic virtual lunar colony online game was recently interviewed on Hotel Mars by John Bachleor of CBS Eye on World and David Livingston of The Space Show. Kim’s website is starting to mature to a point where I thought it was time to get an update and a deeper dive into her vision of our future living on the Moon. I caught up with Kim last week via email.
SSP: Thanks for taking the time to collaborate on this post Kim. You’ve said that accurately depicting and roleplaying the activities of living on the Moon in a colony called Moon Town built by, and shared by, the players will help show the world the benefits of space development and a positive future. Why do you think a role-playing online game is the best vehicle to accomplish this vision?
KH: Because interacting over time with a detailed simulation allows people to absorb what it means. It allows people to pick up knowledge about space development as they play. That’s a kind of learning that sticks. And the more players expand the vision, creating an ever cooler place with more things to see and do, the more they will feel a connection with that vision. They will naturally think about it more, talk about it more, pass on things about it to their friends and family. The kinds of dialogues they are able to have about it will gain depth and breadth, the more they work on it and see how others have worked on it.
“We need to understand what’s coming and make sure we do this right.”
It’s long been said that simulations of this kind will become a major means of education and research once the software and hardware to make them matures. Well, we’re arriving at that day. It’s a question of properly designing them now, to best serve our needs. I think space development is clearly the best choice of theme for the first such simulated environment, and a game based on creation and collaboration is the best design paradigm for it. I’d say there is no issue in the world so misunderstood and undervalued. We need to understand what’s coming and make sure we do this right. Otherwise it will take longer to see the massive benefits, and there are lots of things that could go really wrong.
Depiction of an android accompanying a resident in the shared kitchen, dining area, and spa facility of a neighborhood in Moon Town
SSP: You’ve done a lot of research to make the future technology of Moonwards scientifically accurate to give users a realistic prediction of what it will be like to live and work in space. Why is this important?
KH: There’s lots of places out there where people can enjoy a space fantasy, and I’m a fan of a bunch of them. But to bring home why it’s important to devote big resources to space development, we have to leave no doubt that the benefits we portray will really happen once enough space infrastructure exists. I’ve generally been conservative about what’s portrayed so there’s no gap where someone could say it’s not gonna happen because this or that is fanciful. This is of course difficult because there’s so much we don’t know.
It’s the medical stuff that’s especially hard to account for, as you well know, John. In order for people to enjoy the game it has to portray a beautiful, exciting place. If it doesn’t do that nobody will be interested and it won’t achieve anything. I decided not to build the town in a lava tube, the place widely recognized as the safest, easiest place to build at scale on the moon. The most important reason I chose a large, young crater instead was to present that beautiful, exciting place. However huge a cavern is – and lava tubes on the moon could be hundreds of meters wide and thousands long, in theory – I didn’t feel it could be filled with a city nearly as attractive as one in a crater. No matter that it gives complete protection from radiation and dust, and it’s relatively easy to pressurize the entire thing. Once we can, I’m pretty sure we’ll make big fancy cities in craters or mountains, not tunnels. We’ll do what it takes to create a healthy place to live that has the sunshine and big outdoor views humans have evolved with. I’ve had arguments with people about that but I stick to it. It gives me an opportunity to discuss what systems would be needed and how they could be made on the moon. It gives people a relatable way to learn about such things, and to ponder both the vast scale of this undertaking, and that it’s entirely feasible.
“This isn’t about exploring space. This is about changing human existence. We have to demonstrate this can really be done.”
As people play this game, I want real questions to well up in them for the game world to properly answer. If you want people to really question whether this kind of vast industry and construction is both possible and desirable in space, a place of beauty and wonder has to instill those questions. Then, they must be answered thoroughly with the best science we have. Moonwards isn’t shy about scale, we show things that couldn’t be built without a robotic workforce rivaling the human workforce that built the Panama Canal. When someone is convinced something like that can really be made, that person becomes a true convert. This isn’t about exploring space. This is about changing human existence. We have to demonstrate this can really be done.
Image of a Moon Town resident outside in a capsule spacesuit, on the roof of the first park, with its giant window. The main park is in the distance, its giant stone arches protecting the space from radiation but letting in lots of sun
SSP: Moonwards is open source to encourage collaboration among “Makers” to build out the community of Moon Town. Who are these Makers and what qualifications do they need to participate?
KH: The communities we’ll be wooing directly will be those of space science and industry, and amateur game developers. We need a few more things done before actively bringing in a select few from those communities. The first set of Makers will advise us on design and test our collaboration tools. They’ll use those tools to add things to the game world once we’ve got the version that makes the process a pleasure. Beyond that point, the task is to grow a culture of Makers who decide themselves how the town develops. We just support that process – giving them more and better tools, adding new game destinations for them to work on (eventually starting with an O’Neill cylinder once Moonwards is established), helping polish what they make, and building a rapport with them so together we make the best vision of the future we can.
“Makers develop the major parts of the town, all the things that really require sound engineering.”
So, while initially we’ll be seeking out a small group of people with qualifications that leave no doubt they know how to design this simulation properly, once that group takes the lead in creating content, it will be their opinion of submissions that determines who joins the Maker ranks. We’ll set up the means for anyone to submit proposed content. A critique process will assist with refinements. If your submission meets standards, it’ll be approved and you become a Maker, with all the privileges that go with that. Anyone who does their homework and learns from feedback can acquire that status.
You see, Makers develop the major parts of the town, all the things that really require sound engineering. All such things need good review before being included, and also an active community that integrates new stuff into the whole, considering the overall design and needs of the town. There will be plenty of things that are the ordinary day to day parts of a living town that any player can create and add, and that’s just up to them, and anyone else who shares a space with them. They can make their own home and its contents, things for their neighborhood, shops and markets, even things like animals, robots, and human characters. Makers are a different deal. They expand the town itself and have a big voice in new cities. where to locate them, and how to portray them.
View from outside the ecosystem research lab, showing the ilmenite reactors producing iron and oxygen in the distance. Two robotic rovers are visible center right.
SSP: In the (hopefully near) future when the Full Town Life is realized, visitors will be able to cooperate using a Collaboration App to develop ideas and projects in a workshop space with a suite of 3D modeling tools. How do you envision this functionality furthering space development? Can you give some examples of how it would be used?
KH: (Rubs hands.) Well, I talked above about how Makers will be a culture of informed people able to make good realistic designs for space. So, let’s say a few of them are playing with ideas for systems to transport ore from mines to processing reactors. We’ll start with trucks designed for that. Maybe they wonder if conveyor belts are better for production beyond a certain scale. They draft something for that, and once they are done for the day, the work-in-progress is on display in the studio section of the main habitats. Someone passing by looks at it and realizes they haven’t accounted for the dust that will be flying around in much greater quantities in mining areas. They attach a note about it to the gears that are too exposed, perhaps including a quick 3D sketch of a protective casing, or a link to a library item that could be adapted for a fix. Someone else passes by, thinks it over, and leaves a note with a calculation of what production level would justify this and whether it makes sense. A third person takes a look, and adds a comment to the note about production levels concerning how ore quality could impact the calculation.
“…nothing stops real researchers from using our code and assets to help create simulations adequate for real engineering modeling.”
By the time the original team comes back to work on it some more, someone has proposed an alternate solution using a sort of cable car system with movable posts, and begun working on it in a nearby area of the studio. Someone’s suggested different kinds of buckets used to get the ore from the trench or shaft to the conveyor belt that then clip onto the belt and are taken away. They ask to officially join the team. Someone has provided a miniature map of the main mining zones for use in mocking up the routes for the conveyor belts so they can be optimized, and attached it to the project.
These things can all happen because people actually walk past other people’s work in the game. When they do, they are already in an environment that allows them to play around with the model and attach all sorts of things to it, without changing the version the team behind it is working on. Good design will create the best possible environment for collaboration we’ve ever had.
How much of that will transfer directly to the real world is impossible to say. We have hopes that with growth the quality and capabilities of the simulation aspect of the game will be so high, things created this way will genuinely shape real world designs. This is one of the reasons for the main project to be open source – that way nothing stops real researchers from using our code and assets to help create simulations adequate for real engineering modeling. Then, that can be contributed back to Moonwards and we can adapt it so the game is a better simulation. It can become a virtuous cycle.
Aside from whether real technology might actually be drafted in Moonwards, definitely people will pick up how to engineer by playing. There is huge potential for mentorship, training in creative problem solving, and evaluation of concepts in an environment that makes communicating complex ideas so much easier.
SSP: Eventually, there will be the capability of hosting events such as concerts, live plays, gallery displays, special interviews or discussions. Why would this be an attractive place for visitors to experience events like these?
KH: The kinds of events that I imagine being really successful will draw on the environment, and the nature of the community. Let’s focus on large events, on a scale that requires high bandwidth to work. It’ll take a while to create that capability, but it’s the part that’s really fun.
“With amazing realism quickly becoming possible even in real time 3D rendering, … such events could be fantastic.”
If you go to a concert or a play, the avatars of the audience could be scaled down to be an inch tall, and be free to fly around a space half a meter high by 10 meters wide by 3 deep, arching around the front of the stage just a meter from the performers. You could see the avatars of the viewers closest to you, and anyone you came with, but those farther away could appear just as little lights. The performers could jazz up the event by switching at will between all kinds of avatars, and adding anything they want to the environment. With amazing realism quickly becoming possible even in real time 3D rendering, and live recording of real people in full 3D also quickly maturing, such events could be fantastic.
Of course, Moonwards is a tiny project compared to other ventures pushing into 3D platforms. But we have two advantages that could be a big deal. First, we are the first venture of this kind to be principally open source. Add-ons can be proprietary (some of ours will be, as will the server code), but the main bulk of the project will remain open source. This is attractive to people wishing to experiment with the medium, or who wish to be sure their personal data isn’t being exploited, or who would rather the Metaverse (aka the 3D web) doesn’t grow up to be dominated by a few giant companies, like social media is. It’s possible that could be a decisive factor in who grows over the next decade.
Second, our tribe is those who love space and futurism. If you want to hang out at events with our kind of people, then come to our events. Nobody else will offer a lecture about the formation of Lalande Crater in which the audience is inside a simulation of the impact event.
SSP: In May Moonwards launched a contest to begin upgrades to the virtual infrastructure of Moon Town. Called “Create Lunar Infrastructure in Moonwards Baby!” or CLIMB!, the initiative was intended to draw in Makers to bring the game alive, with proposals submitted over the summer to compete for prizes. How is the contest going?
KH: OK, part of me is tempted to skip this, but another part thinks it’s better to answer. Making this game has been hard up to now. Really, it’s going a lot better than it was – a lot – and we’ve already gotten farther along than most startup video game ventures get at this point. Still, we are a small team on a shoestring budget who go through many unexpected turns. Other tasks meant we were obliged to launch the contest later than we should have, with less resources than we’d have liked. Then an opportunity appeared to enter a business plan contest run by the National Space Society, taking place during the same time as CLIMB!. (Check it out – https://spacebizplan.nss.org/details/). That meant the person working on the contest – me – instead turned full time to writing the business plan. That includes moving up some revisions to the layout of Moon Town so they can be shown off in the plan.
We made some good contacts during the brief time we were actively promoting CLIMB!, but it seems clear there won’t be submissions this year. We’ll take what we’ve learned and make a bigger, better contest next year. We feel having regular contests for new content of various kinds will really help bring in Makers and spread the word.
SSP: Much of the laborious tasks in Moon Town are done by robots. What will the inhabitants do there and what will be the economic benefits and incentives for average people to want to migrate there permanently?
“The answer to what people will do there is, what they are passionate about.”
KH: Ah the future – so much to think about. To scale up industry and transport in the Earth-moon system to the point where some goods from the moon can be sold for a profit on Earth, you really have to go all out with automation. You have to make maximum use of the fact the moon has no biosphere to harm, and turn all labor over to robots that can work in really dangerous environments. Once you manage to have robots make more robots using materials on the moon, and energy beamed from space solar power arrays powers the factories and transport, prices will drop and drop until you can compete with industry on Earth. Ok, if you buy that, then Moon Town is going to be the robot Mecca of the future. Robots don’t just do most of the laborious tasks, they do them all. Running a closed ecosystem on a world so hostile an unprotected person would die in less than a minute requires great care. People just plain aren’t trusted to always do everything important right. Robots do all that. The answer to what people will do there is, what they are passionate about.
I mean, it isn’t like robots won’t have taken most jobs on Earth by that time too. We’re going to have to decide how to assign value to things in a way that rewards merit in a world like that. What can humans do that even intelligent robots can’t? Things that have great emotional value to other humans. Things that help us define who we are. Arts. Sports. Caregiving. Spirituality. Exploration.
Now, that isn’t necessarily to say that a lot of average people will migrate permanently. At least, not to the town we are portraying first. It’s not a huge place, there is a lot a person would have to give up to live there. [See next question]. The city that comes after it would be better suited to welcome average people. The human population of Moon Town will be researchers and top engineers who benefit from being able to take a close look at their work on-site, artists, athletes, and a few administrators. Moon Town plans to embed depictions of their lives as stories woven into the world. Oh, also people with major disabilities who are taking advantage of how Moon Town permits body alteration on a level not legal on Earth, especially advantageous in a controlled, low gravity environment. And some people taking a shot at immortality. Literally.
SSP: Its been said that a space settlement will not be completely self-supporting and independent of Earth until children can be born and raised there. Moonwards deals with human health in the Moon’s 1/6 gravity environment through the use of centrifuges to dose inhabitants for 3 hours a day of 1G conditioning to mitigate the known deleterious effects of lower gravity to human health. But there appears to be no mention of children in Moonwards culture. Given Moonward’s rigorous scientific accuracy, is the lack of children because of our knowledge gaps with respect to the gravity prescription? Will this evolve over time as the Moonwards community is informed by advances in space medicine?
KH: Yes, it’s because of the knowledge gaps. It’s definitely completely unclear whether it’s possible to bear and raise healthy children on the moon. We also can’t anticipate in any way how we might work around that, if it isn’t possible. I’ll be comfortable depicting children in the O’Neill cylinder in orbit. We’ll get to that simulation in due course. With that option sitting there, why get into how to do it on the moon?
(PS – 3 hours a day is of course a total guess and was chosen to be relatively easy to work into gameplay. Media in the game will explain things like this.)
SSP: Speaking of centrifuges for human health in low gravity environments, your design of the health “Carousel” assumes a radius of 16 meters. This relatively small size, as you have acknowledged, could lead to severe Coriolis effects potentially resulting in severe disorientation and nausea. Have you considered a larger centrifuge design such as the one proposed by Gregory Dorais with a radius of 75 meters which could reduce the impact of Coriolis effects, and since Moonwards is depicted far enough in the future that this type of technology could be achievable?
KH: To be fair, the centrifuge portrayed right now is one of the first, in a hab that can’t accommodate anything bigger. The bet is that people who use the apparatus regularly adapt to the way it affects the inner ear, and then are able to use it without issue. This is the theory Al Globus puts forth, with a decent amount of evidence to back it up, based on experiments with centrifuges over the years. But as the town expands, centrifuges are made bigger and bigger.
I’m currently planning a thorough revisit to the town’s design. We are at a juncture in development where it makes sense to change and refine the models of the town, and I intend to take that pretty far. This time, the first habs built will be upright cylinders with rounded ends such that it’s possible to ride a bike around the walls so fast that you are pressed towards the wall with a force of one gravity. Nod of the hat to Jeff Greason for pointing that out. Then the first centrifuge will go in, not sure of the radius but at a guess, 40 meters. The bigger habs will be able to accommodate ones much larger still. But those will be in the hands of the Makers. I’m just making the first few things, and giving ample space for others to expand.
SSP: Currently, space exploration and development is primarily funded by government entities and is regulated by the Outer Space Treaty. As such, these activities are by nature geo-political. You’ve chosen not to deal with these challenges that will inevitably shape our future in space, and leap frogged ahead with the assumption that those issues have been solved. Is the hope that people will be so attracted to the abundant resources and opportunities that Moonwards has to offer, that they will overcome their differences and come together to make it happen?
“Let’s focus on getting across how much better life will be if we pull this off. That’s what matters.”
KH: Heck, I don’t just assume they’ve been solved. I assume the very best decisions have been made along the whole journey, to lead to the very best outcome for space development.
The exercise here is to explore our potential. It’s also important to see how this could go wrong, but as soon as you get into that, you fail to communicate the thing that matters most. This isn’t another chapter in geopolitical expansion, akin to the colonial era. This goes right off the map of anything humanity has ever experienced. Let’s focus on getting across how much better life will be if we pull this off. That’s what matters.
Visit Moonwards to download the game free of charge and start collaborating. Although somewhat dated, check out Kim’s appearance with Dr. Livingston, Haym Benaroya and myself on the Moonwards Panel at the 2017 Icarus Interstellar Starship Congress in Monterey, California.
Conceptual illustration of a planetary sunshade blocking a fraction of sunlight from reaching Earth at the L1 Lagrange point. Credits: Planetary Sunshade Foundation
The Planetary Sunshade Foundation (PSF) would answer “Yes!” to both questions. In a paper presented at the AIAA ASCEND conference in 2020 on the group’s website, the authors* lay out a well researched case on feasibility. The technology needed to build such a megastructure, envisioned to be located at the Earth-Sun L1 Lagrange point, will depend heavily on resource extraction on the Moon and Near Earth Asteroids as well as in-space manufacturing, both of which are anticipated to be mature industries by mid-century.
Building such a megastructure will be a huge undertaking and would require significant funding as well as international cooperation among world governments. PSF and many other groups (including President Joe Biden) take the position that global warming is an existential threat and therefore mitigating its effects are worth the costs. The foundation says on their website that “We have only ten years to dramatically decrease the use of fossil fuels, or be forced to respond to catastrophic global warming.” Other credentialed climate scientists interpret the same data differently disagreeing that if we don’t act now the impact will be catastrophic. They believe that a more gradual transition based on innovation and adaption would make more economic sense.
Dr. Steven Koonin, who served as Undersecretary for Science in the U.S. Department of Energy under President Obama, in his book “Unsettled” uses data from the UN Intergovernmental Panel on Climate Change to show that the impact on the U.S. economy near the end of this century due to the worst scenario of predicted global temperature rise would be minimal. Therefore, in his view the warnings of an “existential threat” are not supported by the data.
Bjorn Lomborg takes the position that rather than making an abrupt change to our economy of reducing carbon emissions to zero by mid century, which is projected to impose significant economic costs and lower standards of living, we need to ramp up our investments in green energy innovation. This would include research and development in renewable energy technology such as solar and wind power, improving battery efficiency, nuclear power and other options to more gradually migrate away from fossil fuels.
The idea of placing a sunshade at L1 to cool the planet is not new, as evidenced by a few examples listed as references in the PSF paper. One of the references published back in 2006 by Roger Angel, Professor of Astronomy and Optical Sciences at the University of Arizona, examines the “Feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1)”. Angel realized that embarking on such an ambitious endeavor should only be initiated to avert serious climate change “…found to be imminent or in progress.” He concludes that “The same massive level of technology innovation and financial investment needed for the sunshade could, if also applied to renewable energy, surely yield better and permanent solutions.”
Such major undertakings among world governments are by nature political, but if agreement is eventually reached by stakeholders on the urgency to build a planetary sunshade, the option will be available to humanity in the near future should it become necessary. The planetary sunshade is technically possible with future technology advances and has the potential for other benefits. For example, if the structure is made from thin-film photovoltaics, it would be possible to collect enough solar energy to provide hundreds of terawatts of power which is many times the current needs of Earth (currently 17TW). PSF believes the sunshade megastructure “…could generate civilization-transforming energy supplies.” The authors even suggest that a toroidal colony like the one conceived in the NASA 1975 Space Settlement Design Study could be constructed nearby to house workers supporting the manufacture of the sunshade and be “…combined to create banded toroidal settlements as well, scaling linearly, depending upon the population needs of the settlement.”
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* The authors ( A. Jehle, E. Scott, and R. Centers) of the paper “A Planetary Sunshade Built from Space Resources” as of last year were graduate students in the Center for Space Resources at the Colorado School of Mines in Golden, Colorado. Centers and Scott are Director and Systems Engineer, respectively on the PSF Team.
Conceptual illustration of a Virtus Solis satellite array beaming power to central California (not to scale). Credits: Virtus Solis Technologies. NOTE: all images in this post are credited to Virtus Solis Technologies
Ever since I was in high school space solar power has been the holy grail of space advocates. I even wrote a report on the topic based on Peter Glaser’s vision in my high school physics class before Gerard K. O’Neill popularized the concept in The High Frontier leveraging it as the economic engine behind orbiting space settlements. But the technology was far from mature back then, and O’Neill knew back in 1976 the other main reason why after all these years space solar power has not been realized:
“If satellite solar power is an alternative as attractive as this discussion indicates, the question is, why is it not being supported and pushed in vigorous way? The answer can be summarized in one phrase: lift costs.” – Gerard K. O’Neill, The High Frontier
John Bucknell, CEO and Founder of Virtus Solis, the company behind the first design to cost space solar power system (SSPS), believes that recent technological advances, not the least of which are plummeting launch costs, will change all that. He claims that his approach will be able to undercut fossil fuel power plants on price. He recently appeared on The Space Show (TSS) with Dr. David Livingston discussing his new venture. SSP reached out to him for an exclusive interview and a deep dive on his approach, the market for space solar power and its impact on space development.
SSP: Technological advancements of all the elements of a space solar power system have gradually matured over the last few decades such that size, mass and costs have been reduced to the point where there are now experiments in space to demonstrate feasibility. For example, SSP has been following the first test of the Naval Research Laboratory’s Photovoltaic Radio-frequency Antenna Module (PRAM) aboard the Air Force’s X37 Orbital test vehicle. Caltech’s Space-based Solar Power Project (SSPP) has been working on a tile configuration that combines the photovoltaic (PV) solar power collection, conversion to radio frequency power, and transmission through antennas in a compact module. According to your write-up in Next Big Future on a talk given to the Power Satellite Economics Group by the SSPP project manager Dr. Rich Madonna, they plan a flight demonstration of the tile configuration this December. The Air Force Research Laboratory’s Space Solar Power Incremental Demonstrations and Research (SSPIDR) project also plans a flight demonstration later this year with an as yet unannounced configuration. Which configuration of this critical element (PRAM or tile) do you think is the most cost effective and can you say if your system will be using one of these two configurations or some other alternative?
Bucknell: There is a lot of merit to the tile configuration as it shares much of it’s manufacturing process with existing printed circuit board (PCB) construction techniques. The PRAM itself is a version of the tile, but as it was Dr. Paul Jaffe’s doctoral dissertation prototype (from 2013) it did not use PCB techniques and should not be considered an intended SSPS architecture. Details of Caltech’s latest design aren’t released, but it appears they intend to deploy a flexible membrane version of the tile to allow automated deployment. Similar story with SSPIDR. As space solar power is a manufacturing play as much as anything, you would choose known large scale manufacturing techniques as your basis for scaling if you intend earth-based manufacturing – which we do. So yes, we are planning a version of the tile configuration.
SSP: You’ve said that the TRL levels of most of the elements of an SSPS are fairly mature but that the wireless power transmission of a full up phased array antenna from space to Earth is at TRL 5-6. The Air Force Research Laboratory (AFRL) plans a prototype flight as the next phase of the SSPIDR project with demonstration of wireless power transmission from LEO to Earth in 2023. What is your timeline for launching a demo and will it beat the Air Force?
Bucknell: Our timescales are similar for a demonstrator, but I suspect the objectives of a military-focused solution would be different than ours. We would plan a LEO technology demonstrator meeting most of the performance metrics required for a MEO commercial deployment.
SSP: Your solution is composed of mass produced, factory-built components including satellites that will be launched repeatedly as needed to build out orbital arrays. Will multiple satellites be launched in one payload or will each module be launched on its own? What is the mass upper limit of each payload and how many launches are needed for the entire system?
Bucknell: We intend a modular solution, such that very few variants are required for all missions. A good performance metric for a SSP satellite would be W/kg – and we believe we can approach 500 W/kg for our satellites (Caltech has demonstrated over 1000 W/kg for their solution). With known launchers and their payloads a 100MW system would take three launches of a Starship, with less capable launchers requiring many more. Since launch cost is inversely related to payload mass, we expect Starship to be the least expensive option although having a competitive launch landscape will help that aspect of the economics with forthcoming launchers from Relativity Space, Astra and Rocket Lab being possibilities.
SSP: The way you have described the Virtus Solis system, it sounds like once your elements are in orbit, additional steps are needed to coordinate them into a functional collector/phased array. Presumably, this requires some sort of on-orbit assembly or automated in-space maneuvering of the modules into the final configuration. I know you are in stealth mode at this point, but can you reveal any details about how the system all comes together?
Bucknell: An on-orbit robotic assembly step is necessary, although the robotic sophistication required is intentionally very low.
SSP: Your system is composed of a constellation of collection/transmitter units placed in multiple elliptical Molniya sun-synchronous orbits with perigee 800-km, apogee 35,000-km and high inclination (e.g. > 60 degrees). I understand this allows the PV collectors to always face the sun while the microwave array can transmit to the target area without the need for physical steering, which simplifies the design of the spacecraft. Upon launch, will the elements be placed in this orbit right away or will they be “assembled” in LEO and then moved to the destination orbit. Do the individual elements or each system assembly as a whole have on-board propulsion?
Bucknell: The concept of operations is array assembly in final orbit, mostly to avoid debris raising from lower orbits.
Schematic illustration of a three-array Virtus Solis constellation in Molniya orbits serving Earth’s Northern Hemisphere and a two-array constellation serving the Southern Hemisphere of Luna
SSP: The primary objective of the AFRL SSPIDR project is delivery of power to forward deployed expeditionary forces on Earth which would assure energy supply with reduced risk and lower logistical costs. It sounds like your system would not work for this application given the need for 2-km diameter rectenna. Could this potential market be a point of entry for your system if it were scaled down or reconfigured in some way?
Bucknell: Wireless Power Transmission (WPT) at orbital to surface distances suffer from diffraction limits, which is true for optics of all kinds. It is not physically possible to place all the power on a small receiver, and therefore the military will likely accept that constraint. As a commercial enterprise, we could not afford to not collect the expensively-acquired and transmitted energy to the ground station. There are also health and safety considerations for higher intensity WPT systems – ours cannot exceed the intensity of sunlight for example, and therefore is not weaponizable.
SSP: You said on TSS that your strategy would, at least initially, bypass utilities in favor of independent power producers. What criteria is required to qualify your system for adoption by these organizations? You mentioned you have already started discussions with one such group. Can you provide any further details about how they would incorporate an SSPS into their existing assets?
Bucknell: One of the key features of space solar power is on-demand dispatchability. Grid-tied space solar power generation has the benefit of being able to bid into existing grids when generation is needed and task the asset to other sites when demand is low. This all assumes that penetration will be gradual, but some potential customers might desire baseload capacity in which case there is not as much need for dispatchability. Each customer’s optimal generation profile is likely to be unique so it is preferable to attempt to match that with a flexible system.
Conceptual illustration of a 1GW Virtus Solis rectenna array next to Topaz Solar Farm of 550MW capacity in San Luis Obispo County, California
SSP: Other companies have alternative SSPS designs planned for this market. For example, SPS – ALPHA by Solar Space Technologies in Australia and CASSIOPeiA by International Electric Company in theUK. How does Virtus Solis differentiate itself from the competition?
Bucknell: From a product perspective, we are able to provide baseload capacity at far lower cost. Also, we intentionally selected orbits to not only reduce costs but to induce sharing of the orbital assets across the globe such that this is not a solution just for one country or region.
SSP: How big is the likely commercial market for your product/services going to be by the time you are ready to start commercial operations? Can you share some of your assumptions and how they are derived?
Bucknell: Recent data indicates that electrical generation infrastructure worldwide is about $1.5T annually. If you add fossil fuel prospecting, it is $3.5T. Total worldwide generation market size is about $8T. All of this is derived from BP’s “Statistical Review of World Energy – June 2018” and the report from the International Energy Agency “World Energy Investment 2018”
SSP: For your company to start operations, what total funding will be required, and will it come from a combination of government and private sources, or will you be securing funding only from private investors?
Bucknell: As a startup, especially in hardware, funding comes from where you can get it. To date no governmental funding opportunities have matched our technology, but that might change. Our early raise has been from angel investors and venture capital firms. Over the course of the research and development efforts, we expect demand for capital will be below $100M over the next several years but accurately forecasting the future is challenging. We would note this level of required investment is far below our competition.
SSP: For hiring your management team, since this business is not mature, what analogous industries would you be looking at to recruit top talent?
Bucknell: Everything in our systems exist today elsewhere. The wireless data industry (5G for example) has the tools and experience for developing radio frequency antennas and associated broadcast hardware. The automotive industry has extensive experience with manufacturing electronics at low cost in high volumes, including power and control electronics. Controls software engineering is a large field in aerospace and automotive, but in a large distributed system like ours the controls software will extend far beyond guidance, navigation and control (GNC).
SSP: O’Neill envisioned the production of SSPSs as the market driver for space settlements, in addition to replication of more space colonies. This approach seems to have gathered less steam over the years as economics, technological improvements, and safety concerns have taken people out of the equation to build SSPSs in space. In a recent article in the German online publication 1E9 Magazine you talked about SSPSs being useful for settlements on the Moon and Mars. What role do you see them playing in free space settlements and could they still help realize O’Neill’s vision?
Bucknell: We stand at a cross-roads for in-space infrastructure. For the first time access to space costs look to be low enough to make viable commercial reasons to deploy large amounts of infrastructure into cislunar space and beyond. To date the infrastructure beyond earth observation and telecom has been deployed to mostly satisfy nation-state needs for science unable to be performed anywhere else as well as exploration missions (also a form of science). However, there has to be a strong pull/demand to spur the construction of access to space hardware (heavy lift rockets) that consequently lowers the cost further through economies of scale. As I described in my Space Show interview there are only a few commercial in-space businesses that are viable with today’s launch costs. We have had telecom for a long time, followed closely by military and then commercial earth observation. Now we have a large constellation of “internet of space”. Even with those applications, there is not a large pull to scale reusable launch vehicle production – as reusability is counter-productive for economies of scale. A large, self-supporting in-space infrastructure would be needed to bootstrap launch production sufficiently to self-fulfil low cost access to space – Space Solar Power is that infrastructure. Space tourism, asteroid mining and others do not have scale nor potential lofted mass to scale the launch market adequately. In that way, O’Neill’s vision is right – and the follow-on markets can leverage the largely paid-for launch infrastructure to make themselves viable. Space solar power will be the enabler for humanity to live and work off-Earth, and Virtus Solis is leading the way.
Illustration of photonic laser thruster infrastructure for in-space transportation in cislunar space. Credits: Young K. Bae
Y.K. Bae Corp is on the verge of testing a revolutionary photonic laser thruster (PLT) that could be a game changer for in space propulsion and interplanetary travel. Founder and Chief Scientist Young K. Bae Ph.D described the technology in a recent Future In-Space Operations (FISO) Telecon presentation. The secret is generating thrust through photon pressure of a recycled laser beam enabling high energy to thrust efficiency without onboard propellant. Y.K. Bae Corp’s Continuous-Operation laser thruster or PLT-C is capable of delivering continuous thrust for long periods of time (e.g. days – years). The crew/payload section of the craft contains no power supplies, fuel or rocket engines. A power source is needed at the destination to generate a velocity reversal and stopping beam.
Dr. Bae believes an in-space “photonic railway” using this technology could open the solar system to commercialization and laid out a timeline for development of the photonic laser thruster. He believes that a 1 Newton (N) thrust PLT demonstration on the ISS could be accomplished within 3 years, a 50-N thrust PLT suborbital lunar launch is possible within 10 years, transits to the Moon can be done within 20 years and trips to Mars/Asteroids are projected to be in the 30 – 40 year timeframe.
When scaled up, super high ∆v can be achieved using the PLT. With a total electric laser power of 1000MW, travel times from the Earth to Mars could be achieved in less then 20 days for a 1-ton ship with 50% payload. From Mars out to Jupiter, a trip would take about 45 days for a craft with the same mass. The PLT spacecraft could be the main mode of rapid in-space transportation for humans and high price or lighter commodities after conventional thrusters (e.g. chemical rockets) establish the initial infrastructure and continue as the transportation choice for low cost or heavier payloads.
Illustration of a photonic railway using PLT infrastructure for in-space propulsion established at (from right to left, not to scale) Earth, Mars, Jupiter, Pluto and beyond. Credits: Young K. Bae.
Y.K. Bae Corp has demonstrated the photonic laser thruster technology in the lab. Check out their cubesat demo video.
Artist depiction of a lander descending to the lunar surface carrying a rover housing Masten’s Rocket Mining System. Credits: Masten Space Systems
Called RocketM for Resource Ore Concentrator using Kinetic Energy Targeted Mining, Masten Space Systems has partnered with Honeybee Robotics and Lunar Outpost to design a novel system for blasting ice out of lunar regolith for ISRU under NASA’s Break the Ice Lunar Challenge program.
Lunar Outpost rover decending to the lunar surface down a ramp deployed off a Masten lander. Credits: Masten Space Systems
RocketM equipment would be housed aboard a Lunar Outpost rover delivered to lunar surface via Masten’s lunar lander. After unloading, the rover would be robotically navigated by a geologic team to an excavation site in the Aitken Basin near the Moon’s south pole. Upon arrival over the target area, the RocketM dome is extended down to the surface to create a seal over the regolith. A rocket is then ignited in a series of 1/2 second pulses fluidizing the regolith into icy grains which are conveyed out of the dome via a Honeybee Robotics PlanetVac pneumatic sampling system for processing. Beneficiation of the particles is accomplished using an Aqua Factorem process for separation into purified ice and other useful components. Aqua Factorem has been covered by SSP in a previous post. The whole process would only take 5-10 minutes.
A view of the inner workings of RocketM showing a centrally located pressure dome extending down to form a seal on the lunar surface. Credits: Masten Space SystemsCutaway view showing a 100lb thrust rocket engine firing half-second bursts to heat the regolith to a depth of 2 meters releasing icy grains for processing to extract water. Credits: Masten Space Systems.
The stored water can subsequently be electrolyzed using solar energy into hydrogen and oxygen for lunar operations. What is so exciting about this ISRU system is that the rocket engine can be refueled by the mined products enabling an estimated useful life of 5 years.
Masten has tested the system using simulated lunar regolith providing groundwork toward optimizing conditions within the pressure dome. Further testing is needed at the system level to validate flight readiness.
As stated on Masten’s blog: “Usable as drinking water, rocket fuel, and other vital resources, lunar ice extraction is critical to maintain a sustained presence on the Moon and allow future missions to Mars and beyond. It can also be used in conjunction with other volatiles found in lunar regolith, such as oxygen and methane, to support energy, construction, and manufacturing needs. There’s a lot of promise – water excavation is just step one!”
Artist renderings of an autonomous pneumatic handling system using SHEPHERD technology. An asteroid is first carefully enclosed in a touchless manner within a sealed fabric envelope, de-spun and de-tumbled through friction with an introduced controlling gas, then driven by continuous gas flow to introduce delta-V and deliver the asteroid to a target destination. Chemical and thermal interaction between the introduced atmosphere and the asteroid will permit fuel and water extraction, 3D electroforming of parts from metal sources and the creation of in-space biospheres to feed large habitats. Concept depicted by: Bruce Damer and Ryan Norkus with key design partnership from Peter Jenniskens and Julian Nott. Note: all of the illustrations in this post are credited as above unless otherwise indicated
The SHEPHERD concept for gentle asteroid retrieval with a gas-filled enclosure, an SSP favorite open source technology, has been covered in a previous post. Dr. Bruce Damer, one of the coinventors of the system, recently appeared on SpaceWatch.Global’s Space Café podcast where he revisited this promising technology for capturing asteroids, mobilizing them and extracting key materials to support space settlement (which can be found near the end of the recording). SHEPHERD could solve the three main sourcing problems of sustainable spaceflight and habitation: harvesting volatiles, building materials, and sources of food. Dr. Damer has also been busy with his (and UCSC Prof. David Deamer’s) Hot Spring Hypothesis, a testable theory regarding the place and mechanism of the life’s origins on the Earth, which was the main focus of the podcast. In fact, the arc of his career has tied these two endeavors together in interesting ways. SSP reached out to Dr. Damer for an exclusive interview via email on these groundbreaking topics.
SSP: Dr. Damer, thank you so much for taking the time to answer my questions about SHEPHERD. I’ve been excited and intrigued with the technology ever since I saw the initial paper and your 2015 TEDx talk. Can you give our readers an overview of the concept?
Damer: The goal for SHEPHERD is to provide a universal technology to open the solar system to sustainable spaceflight and beyond that, to large scale human colonization (see figures and explanations for Fuel, Miner and Bio variants below). Enclosing an asteroid (or Near-Earth Object-NEO) within a fabric membrane and introducing a controlling gas would turn that asteroid into a “small world”. The temperature of the gas, its chemical composition and gas pressure forces set up within it can enable multiple in-situ resource utilization (ISRU) scenarios. Initially, the extraction of water and other volatiles from icy NEOs could provide fueling stations with deliveries throughout the solar system. Next, the use of the Mond-process carbonyl gas extraction from high-metallic NEOs can provide electroform 3D printing of large parts in space for construction of habitats. Lastly, melting the ice content of a NEO to a liquid phase surrounding its rocky core enables the introduction of microbes, algae and even some aquatic animals into a biosphere, a mini-Earth terrarium sustained in space. This one invention could provide many of the elements necessary for sustainable spaceflight but also for the construction and support of in-space and surface-located planetary and lunar habitats for thousands or millions of inhabitants. Co-inventor of the design, Dr. Peter Jenniskens at the SETI Institute, calls this the “sailing ship for space” harkening back to how his Dutch ancestors helped open the Earth to commerce centuries ago.
SHEPHERD-Fuel variant with volatiles such as water ice sublimating from the NEO into a warming gas, the resulting water vapor pumped down and condensed into liquids in storage tanks and then separated into hydrogen and oxygen. These tanks become the fuel source for a self-propelling tanker block which can be delivered to a refueling rendezvous point such as Earth cislunar space or Mars orbitSHEPHERD-Miner version with an introduced carbonyl gas and an electric field dipole drawing off ions from a metallic NEO and layering them on a mandrel (shown on the left) to create a precision 3D part such as blocks, beams or tanks for space habitat constructionSHEPHERD-Bio variant sustaining a liquid biosphere around the rocky core of a NEO, with a lit interior and boom to introduce and extract organic materials. A balance of microbes, algae, and even small aquatic animals could maintain this small world, a “terrarium in space” to support large populations in habitats and at surface coloniesSHEPHERD-Fuel variant in Mars orbit or at some distance away showing the delivery of re-fillable tanker block sections to a Mars mission, the nearly empty block propelling itself for refilling. In this way ample fuel is provided in-situ prior to the craft arriving at Mars, with mission lander fuels, water for human consumption, shielding and return propellant provided in orbit in advance without having to extract volatiles from the Mars atmosphere or regolithVision of SHEPHERD Miner and Bio variants supporting a large habitat in LEO with the mantra of: “built in space, and fed in space”
SSP: Have there been any developments or updates to the concept since the initial TEDx talk and NewSpace Journal paper which both came out in 2015?
Damer: Back then we thought that no company or government had the will or capability to invest in such an opportunity, but this is now changing. The roaring success of NewSpace ventures such as SpaceX and their dual award of NASA’s Artemis Program returning humans to the moon based on reusable crewed launches and their recent successful low altitude testing rounds for Starship, has totally changed the space landscape of the near future. Jeff Bezos’ vision for megastructures in space based on the O’Neill colonies of the 1970s would require substantial asteroid resourcing. Elon Musk’s vision for large surface colonies on Mars would be equally well supported by simple, automated space based ISRU which overcomes substantial mining and manufacturing hazards attempting to process bulk materials on the surface of Mars or the moon. In addition, Bigelow’s success with inflatables, China’s surging space program with a new crewed station and rovers on the moon and Mars, all point to much more traffic and demand, especially for fueling depots, as early as the mid-2030s. Reducing the cost of lifting heavy and bulky materials from Earth may never be competitive to extraction, electroforming and farming in space with low-cost delivery directly to points of demand.
Earlier this year I determined that the time was right to place our invention out into the field again and seek partners to join in a development roadmap that will provide a solid financial and technical ladder for SHEPHERD’s maturation.
At a NASA/SETI meeting in January 2019 I was discussing SHEPHERD with members of the Luxembourg Space Agency and was overheard by space entrepreneur Carlos Calva. He approached me and offered that he would work with me to make SHEPHERD into a business. Subsequent meetings at SETI with my co-designer Peter Jenniskens (Julian Nott had died tragically in a ballooning accident) gave us early insights into SHEPHERD’s developmental timeline.
In that spring of 2019 Carlos and I engaged in a rapid-fire series of meetings developing a short-term cash business model for SHEPHERD which would provide a financial lever for the technology. Capturing, moving, and extracting resources from asteroids is a longer-term (15+ years) play, with no immediately apparent buyer for the first potential products: volatiles for propulsive fuel, air, water, and other crew consumables. Elon Musk and SpaceX might reach a point in this decade when they would buy a futures contract for hundreds, or thousands of tons of water and fuel delivered into Earth and Mars orbits sometime in the 2030s. Jeff Bezos may also want to finance the development of SHEPHERD as a technology for delivery of resources to build space habitats much as he has with Amazon’s funding of drone and other robotic fulfillment innovations.
But how to prove SHEPHERD as a technology and then sustain it as a business for long enough to be ready for either of these clients? We settled on two emerging market opportunities: 1) satellite servicing and decommissioning, and 2) hazardous debris removal and deorbiting. Both are potential cash businesses that could provide us achievable milestones to support the multiple investment rounds required. Satellite servicing and debris removal or de-risking is an urgent unmet market need for both governments and commercial operators worldwide. Along with the CubeSat revolution, SpaceX’s reusable launch platform and Bigelow Aerospace’s success with the inflatable Genesis and BEAM module on the ISS, many core technologies were maturing.
Making SHEPHERD into a viable sailing ship for space will not be without its challenges. Designing and flying a fabric enclosure which can open, admit an object (a satellite, a chunk of debris, or a space rock) and then closing it tight, sealing it well enough to fill it with a controlling gas was a major technical challenge which NASA identified in their review of our 2014 Broad Agency Announcement proposal for the asteroid redirect program (since cancelled). The tried-and-true way to make a new space system work reliably is to build scale models, test them to failure, and test them again.
SSP: You mentioned that some of the capabilities of the system could be tested in LEO with CubeSats. Since the technology is open source, has anyone reached out to you to develop hardware for such an experiment? What would be tested and how?
Damer: Carlos and I made a bee-line for the world-renowned annual CubeSat Developer Conference meeting at Cal State San Luis Obispo in April of 2019 where we were able to interact with many of the leading thinkers and solution providers in the CubeSat industry. We devised a back-of-an-envelope LEO test vehicle flight series and made some key contacts. For a small investment (2-4 million USD), an effective six test flight series with a 4U CubeSat would first deploy a gas filled bag into which we could release a target object (such as a real meteorite which would be returned to space). The images below depict this scenario. Later flights in the series could have the target released to space and then the CubeSat would match orbits, track, enclose and seal the object into the enclosure. Key for any test is the ability to manage the object within the enclosure such that it does not contact the fabric. This would not be an issue for our small CubeSat, but it would be a potentially catastrophic encounter for a satellite or NEO. The key to safety (SHEPHERD stands for Secure Handling through Enclosure of Planetesimals Headed for Earth-Moon Retrograde Delivery) is that the system is touchless. In the image below we see gas jets firing to move the object toward and hold it in the center of the enclosure.
SHEP Cube test vehicleInflation of bag enclosure using controlling gas, introduced target object (perhaps a meteorite returned to space)Management of target object position with gas jetsLit interior showing target centered safely in the enclosure
All of this early effort to build and fly the CubeSat missions would mature our IP including: tracking, gas fluid dynamics for handling and enclosure deployment and sealing. We could then value the company and seek a round of investment from governmental or commercial partners in the satellite servicing and debris removal markets.
SSP: How do you foresee these two potential near term commercial applications generating sufficient revenue to “pay the way” for SHEPHERD to achieve its long-term goals?
A much larger SHEPHERD version with an enclosure for capture and servicing of a high value large satellite. Servicing could either be carried out with a robotic bay or by astronaut mechanics flying on SpaceX Dragon, who enter through an airlock and can breathe a low-pressure Earth atmosphere negating the need for bulky EVA/space suits
Damer: Paying the way for SHEPHERD could come from a mixture of satellite servicing (expensive “big birds” for the US DOD or communication satellite operators), orbit graveyarding (for GEO, or de-orbiting from LEO), and of course mitigation of dangerous space debris to head off Humanity’s disastrous encounter with the “Kessler syndrome” as depicted in the movie Gravity. In-space satellite servicing via robotic spacecraft is problematic, requiring very high-risk grappling procedures between vehicles which have no built-in standard grappling mechanism. SHEPHERD provides a gas-based “pneumatic” way to safely envelop and control spacecraft without hard contact. Early computational studies at the SETI institute in 2014 established that a shape model of multi-ton asteroid 2008 TC3 could be de-tumbled and de-spun in less than 24 hours if the object was interacting within a gas at 10% Earth atmosphere pressure. The friction of the satellite or chunk of debris with the gas will bring it to a standstill, then gas jets can be used to rotate and position the enclosed spacecraft for servicing. Imparting a continuous driving force onto the craft using these same jets can create sufficient delta-V to change its orbit. Such safe handling and mobilization of objects in space is key to a whole range of future space operations. The irregularity of satellite shapes (including long booms or antennae) presents fewer challenges to SHEPHERD’s scale and size-independent gas handling system than they would to a robotic or crewed “jet pack” style EVA servicing as we saw with the Space Shuttle’s Hubble servicing missions.
If a satellite servicing, extension of life, or safe decommissioning capability were clearly on the horizon, supporters of international treaties and reinsurance companies could create guaranties, service contracts and insurance instruments which would finance a first generation of SHEPHERD vehicles.
SSP: What do you see as the full vision for the sustainable space architecture which SHEPHERD could enable?
A full vision of the architecture enabled by SHPHERD supporting near-Earth habitats, interplanetary missions, and a class of continuously cycling robotic and crewed spacecraft. Cycling visits of SHEPHERD ISRU supply depots could capture, relocate and extract from asteroids of all sizes and compositions. Eventually a mature SHEPHERD architecture could scale up enclosure sizes to provide the Earth a comprehensive planetary protection shield from larger NEO impact hazards
Damer: The image above depicts the enabling of SHEPHERD-derived spacecraft and processing facilities to support both near Earth space stations and larger megastructure colonies, robotic and human exploration of the inner solar system and beyond. I envision the SHEPHERD business being most akin to the mining industry I was raised around in British Columbia and as depicted in the Sci Fi series The Expanse. Some companies would fly prospecting (and orbit determination) missions to NEO targets, file claims and then sell them on to development companies. Those companies would license or build SHEPHERD-class spacecraft financed through contracts for future deliveries of commodities to companies and governments. Buyers would eventually acquire the risk-taking development companies and leverage them to support much larger projects such as space settlement megastructures or to supply Mars surface colony operations. Over time, scaling of the SHEPHERD system enclosure sizes would permit the safe handling and redirection of Earth-threatening asteroids giving us all a planetary protection shield. A great deal of Astrobiology science could also be supported such as the delivery of a pristine carbonaceous asteroid to Lunar orbit (see below) for astronaut geologists to sample. These samples might give us clues as to how life began on the Earth through the delivery of abundant organics from asteroids like this.
Release of pristine asteroid into Lunar orbit to support sampling by Astrobiologists looking for clues to life’s origins on the Earth, four billion years ago
SSP: What are the next steps for SHEPHERD?
Damer: The COVID-19 pandemic caused a pause on SHEPHERD’s development both as an engineering concept and a business. When I was invited to appear on the Space Café podcast in April (of 2021), I decided to bring it up again to gauge public interest and bring it to leaders in New Space. This interview with you is the next step in developing that interest, calling forward a development team. What I am also seeking is critical input from the community on the concept, leadership in research, and the formation of a company or university research program with financial support for the early on-ground computational and test-article studies leading up to CubeSat flights.
I specifically “open sourced” the basic concept of SHEPHERD on behalf of the three co-inventors in my 2015 TEDx talk, but IP developed by one or more implementers of this core concept can provide them and their investors with protectable value. The seal closure will be one key patentable innovation. Together with a team of keen and willing supporters including myself and Carlos, we produced a pitch deck which was first premiered at the Space Resources Roundtable held at the Colorado School of Mines in May of 2019. This deck concisely lays out the initial cash business in satellite servicing and debris removal and the engineering we have done around the CubeSat and larger variants. Carlos is back at work on the key steps of recruiting engineering leadership and funding for the ground-based development. I am open to inquiries from qualified contacts who wish to discuss their involvement seriously.
SSP: As you described above, of the three key applications of SHEPHERD, one could be food production for space settlements by creating a fully self-contained biosphere out of an asteroid, a mini-Earth if you will. This complements your Hot Springs Hypothesis for life’s beginnings in its method for seeding space with life beyond Earth. Is there an underlying principle linking the origin of life and humanity’s role in extending it beyond the cradle of the Earth?
Series of three images showing cellular mitosis beginning with fission of the nucleus, mitosis underway and completion of the process with daughter cells separatedSHEPHERD Bio with image of Earth overlain on its 500m diameter terrarium worldMitosis of the Earth into “daughter worlds” represented by the arising of SHEPHERD-Bio in the solar system
Damer: Thank you for asking this question! A couple of years ago I literally sat bolt upright in bed having had a dream of a future vision of the solar system, possibly from the year 2100. A ring of asteroids had become enclosed with SHEPHERD craft or some derivative thereof, and thousands to millions of “new worlds” were orbiting the sun. In nearby orbits were the sharply geometric and tubular shapes of space settlements under construction, housing billions of humans and the organisms with which they cohabitate. Evolution had a future path, moving off our birth world by first creating many new ones. Like the first living cells, the Earth had undergone a spectacular mitosis! I realized in a flash that this future solar system was a huge scale evolution of the ancient hot spring pool cycling with membrane-enclosed protocells which Dave Deamer and I have proposed for life’s beginning. The principal of membranous encapsulation enabling chemical activity and resource sharing acted out four billion years ago in hot spring pools would return to enable life to emerge from the womb of the Earth into a long evolutionary future in the cosmos. It was truly gratifying. You can see how I then wove together these stunning parallel visions in my two TEDx talks below.
The SHEPHERD project is dedicated to the memory and genius of Julian Nott (right) at home in Santa Barbara during my 2014 visit
