Planetary Radio • Nov 04, 2020

A Return to Asteroid Mining, and Digging Into Space Ethics with Joel Sercel

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Joel Sercel

Founder and Principal Engineer for TransAstra Corporation

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Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

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Mat Kaplan

Senior Communications Adviser and former Host of Planetary Radio for The Planetary Society

At least two ambitious, smart asteroid mining companies have gone bust. Joel Sercel makes the case that his new effort comes at a much better time, and with a better approach. He’ll also share his audacious plan for mining water on the Moon, along with his concerns regarding humanity’s spread across the solar system. Can we avoid the mistakes made in past eras of exploration and expansion? You’ve got one more chance to win your own asteroid—a small, rubber one—in this week’s What’s Up space trivia contest.

TransAstra Mini Bee
TransAstra Mini Bee The TransAstra Mini Bee is a technology demonstrator of the company's much larger Honey Bee spacecraft. It may be tested in space as soon as 2023.Image: TransAstra Corporation
Mining water in the lunar poles
Mining water in the lunar poles A diagram of TransAstra's proposal for mining water in the permanently-shaded regions of the lunar poles. Note the Sun Flower tensegrity towers that elevate solar reflectors above the rim of the crater.Image: TransAstra Corporation
TransAstra Honey Bee asteroid miner
TransAstra Honey Bee asteroid miner The TransAstra Honey Bee is designed to collect up 100 tons of water and other volatiles from a Near-Earth Asteroid that is as big as a house.Image: TransAstra Corporation

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Trivia Contest

This week's prizes:

A Planetary Society KickAsteroid r-r-r-rubber asteroid! (You can mine it if you like).

This week's question:

How many of the largest dwarf planet Pluto would fit inside the smallest planet, Mercury? Just a basic volume-to-volume comparison, please.

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Wednesday, November 11th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

As measured by either volume or average diameter, what is the smallest asteroid that has been visited by a spacecraft?


The winner will be revealed next week.

Question from the 21 October space trivia contest:

How many robotic spacecraft have returned samples from the Moon and beyond?


Six robotic spacecraft have so far returned samples from the Moon and beyond. Hayabusa2 is almost home and OSIRIS-REx is expected in 2023.


Mat Kaplan: The return of asteroid mining and the ethics of space development, this week on Planetary Radio. Welcome. I'm Matt Kaplan of the Planetary Society with more of the human adventure across our solar system and beyond. We are about to spend a good long while with Dr. Joel Sercel. We will indeed talk about mining asteroids and how he hopes to accomplish this, but we'll also talk about how the coming explosion of commercial space development can avoid the ethical challenges of previous eras of exploration.

Mat Kaplan: I think you'll be as fascinated and stimulated by what Joel has to say as I was. Don't worry, we'll save a few minutes for our weekly visit with Bruce Betts, including another space trivia contest you can enter. You should have been able to enjoy the November space policy edition not long after this show is published, but we're going to make you wait an extra week I'm afraid with good reason. Casey Dryer and I worry that we may not yet know who will be president of the United States by the first Friday in November.

Mat Kaplan: Who knows? We may still not know by the second Friday, November 13th, but we hope we will. And that's when you'll hear the next SPE. If things go well for SpaceX, we will also be just a day away from the first operational launch of a crew Dragon capsule, faring astronauts to the international space station. As I speak, that event is scheduled for Saturday, November 14th. It's not too late to catch the Halloween edition of the downlink.

Mat Kaplan: Wait till you see it's eerie image of a jack-o-lantern sun, no Photoshop required. Here are samples of other stories you'll find below that picture. You'll probably remember our delightful conversation with Jane Grieves about data indicating phosphene in the atmosphere of Venus. Well, new papers, including one coauthored by Jane declare that the possibly life generated gas has not been detected. However disappointing that may be, remember, this is exactly how science is supposed to work. Besides, we don't yet have the final word.

Mat Kaplan: Other headlines lead to the discovery of water on much more of the moon than what's been found at the poles and the siding of an earth sized rogue planet wandering the Milky way. We'll talk with one of the researchers behind that announcement next week. And we can congratulate OSIRIS REx principal investigator, Dante Loretta, and his team yet again. They were able to successfully stow that sample collection head, which may be chock full of Benu bits. We really need to trademark that.

Mat Kaplan: These stories and much more are at Before we get to this week's main attraction, I've got a favorite to ask. I rarely bring this up and I usually save it for the end of the show. This time I'm asking upfront, if you'll help us tell the world about Planetary Radio. It's easy and the best place to do it is Apple Podcasts. Please consider leaving us a review and or a rating. This stuff really matters. It takes moments. Won't cost you a cent, and I'll be very grateful.

Mat Kaplan: Joel Sercel spent 14 years at the jet propulsion lab and then another 12 at the nearby California Institute of Technology researching and guiding students toward careers in space systems engineering. He was chief systems engineer for a $22 billion US Air Force Satellite Network. And he's been a consultant on many other projects. I very quickly though, got the impression that it's his current work as founder and principal engineer of Trans Astronautical Corporation that is most rewarding.

Mat Kaplan: Also known as TransAstra, the company says it is dedicated to opening the solar system to humanity, to building the transcontinental railroad of space. No one yet knows whether TransAstra will be more successful than others at this daunting task, but I couldn't help but be inspired by the dreams he is working so hard to realize. My deep conversation with Joel a few days ago began with asteroid mining and the technologies TransAstra is pioneering.

Mat Kaplan: But as you'll hear, he is also deeply concerned about making sure humanity gets it right in this new era of exploration. By the way, the first minute or so of my audio is distorted for unknown reasons, but it quickly clears up. Joel, thanks so much for joining us on Planetary Radio. This is something that I've been looking forward to for quite a while. You know, when we first talked, you said you wanted to come on the show to talk about the extension of human ethics and ethical concerns across the solar system.

Mat Kaplan: I said, "Sure, but we also have to talk about your day job." And that's where I want to start if you don't mind. Welcome once again.

Joel Sercel: Thank you so much. I'm just delighted to be here. Happy to talk about all that stuff.

Mat Kaplan: I looked at the entire long list of NIAC fellows and NIAC studies yesterday. And I saw that a handful of fellows had three or even four studies that had been funded by NIAC, the NASA Innovative Advanced Concepts or NIAC program. No one had five, you've had six. They seem to think that you have some pretty good ideas.

Joel Sercel: Yeah, well, I don't know where they got that idea, but I'll take it. I have to pinch myself. It's such an honor. I can't believe how successful we've been. And I feel very lucky.

Mat Kaplan: I didn't realize that you also had among these six, the very first phase three project. I am sure that's something you were very proud of.

Joel Sercel: We're extremely proud of it. And we're very excited about it. It's the culmination of several years of work, maybe a lifetime of thinking about the problem. And it's extremely exciting because we're getting to build a prototype of our Mini Bee flight demonstrator for asteroid mining. Several years ago, we invented a process that we call optical mining for using concentrated sunlight to excavate asteroid surfaces and extract the volatile chemicals, water, carbon dioxide, methane, that sort of stuff that can be used to make rocket propellant in space.

Joel Sercel: Our vision is to fly pretty big spacecraft, the Honey Bee and the Queen Bee. The Honey Bee is a spacecraft that's about as big as one of those really large geostationary communication satellites. And it will take the full capacity of a Falcon 9 to launch it into space. And it'll go out and harvest maybe 100 tons of water and other volatile materials from a near-Earth asteroid, but that's a big system.

Joel Sercel: That'll cost you no more than $100 million to develop and we need to prove all the technologies for it. So we came up with the idea of something that we call Mini Bee, which is a tabletop size spacecraft. It could fit on a big dining room table. The idea is that we're going to fly artificial synthetic asteroid about the size of a beach ball in lower earth orbit with the Mini Bee and use the Mini Bee to demonstrate that we can capture the asteroid, mine useful materials from it, and then use water as rocket propellant with our omnivore solar thermal thruster.

Joel Sercel: So we're super excited about it. We have a brilliant young engineering team that's working like mad on building the Mini Bee. We're not flying it in space on this program, but we are building a full prototype of the Mini Bee spacecraft. And in fact, we just had our one-year continuation review with NASA yesterday, and they said they were delighted with our progress. So we're very excited about it.

Mat Kaplan: Wow. Congratulations on that. I want to get into other details of the system itself. But because you were talking about asteroid mining, I know people, I bet you do too, who started companies with this goal? They were smart, dedicated, well-funded, and now they're essentially gone. What sets TransAstra apart?

Joel Sercel: Well, I think it's a matter of three things. Timing, strategy, and innovation. In terms of timing, five years ago was we think the wrong time to start an asteroid mining company if your intention is to go out and fly to the asteroids right away. There's all kinds of exciting things happening in space. But the reason to go to asteroids in the near term is to harvest their materials as rocket propellant. In space, water costs more than gold on the ground.

Joel Sercel: It's an extremely valuable commodity, but there isn't the demand. Or let's say there wasn't the demand in 2017, 2018 for the quantities of water that it makes sense to mine from asteroids for economic purposes. If you're not bringing back sort of at least 100 tons at a shot, it's probably not economical. And there just hasn't been that market. But as Jeff Bezos with his Blue Origin company and Elon Musk with SpaceX are gearing up, and as NASA is getting serious about deep space human exploration, the markets for those propellant are opening up.

Joel Sercel: So part of it was a matter of timing. Part of it was a matter of strategy. From the start, TransAstra was a little different than those other companies, because we've focused like a laser on the core technological issues with asteroid mining, not the peripheral issues. There's a real temptation when you start a space company to develop expertise in building spacecraft. The problem with that is that building spacecraft is really kind of a commodity business.

Joel Sercel: There are lots of aerospace companies that know how to build spacecraft and having a really great building spacecraft capability really doesn't get you very far ahead in the asteroid mining business. So from day one, what we really have been focusing on are the deep technologies that are required to figure out how to handle an asteroid and mine an asteroid in deep space. And I think that's one of the strategic differences that has set us apart.

Joel Sercel: And because we focused on that, you really start thinking about the problem now, how do I mine an asteroid? You get creative and gifted minds around the problem. And then you start coming up with innovations that other people haven't had. And so, we've been lucky enough to invent the optical mining process, which is patent pending. And right now, we're in that back and forth process with the patent office on it. Also because we were focusing on the fundamental technology, we could partner with NASA and such that NASA is actually funding us to develop the technology.

Joel Sercel: And that means that we don't have to take as much investment money from the investment community. When you take money from the investment community, they want a return real fast. And if they don't get that return, it really boxes you into a corner. Yes, we have accepted investment money, but we try to keep that to a minimum. And we take what in investment terms is called undiluted funding from NASA. If you're a business person, you really like undiluted funding.

Joel Sercel: Diluted funding is when some investor comes to you and says, "Hey, I'd like to put a million dollars into your company." And you say, "Well, that sounds wonderful." And then the investor says, "And for that, I want 20% of your stock in the company." So that dilutes your share of ownership. We're lucky that we do have very important investors. We're deeply grateful to them, but they understand that this is a long haul. This is not a short term flash in the pan type effort. And we're able to run the company with a focus on the technology and the innovation that's really going to make it happen.

Mat Kaplan: Let's talk more about this technology beginning with something that I read that really, you're not talking bleeding edge in a lot of ways here, that in fact some of your technologies are pretty well-proven and even look back to that ill-fated Asteroid Redirect Mission or ARM that NASA was pursuing and now seems to have dropped. Is that correct?

Joel Sercel: That's true. The ARM mission, the Asteroid Redirect Mission that NASA was investing pretty significantly in, NASA had hoped to fly the ARM mission, go out to an asteroid. And at one point what they had planned to do is capture an asteroid, maybe 1000 ton asteroid. 1000 ton asteroid is about as big as a single family home, If you think of it in terms of volume. Capture IT in a bag and then bring it back to the earth using ion propulsion. NASA is not the first organization to talk about capturing asteroids in bags. There's a lot of really practical reasons why you want to do that.

Joel Sercel: But what was great about it is that they really invested a lot in the technology to prove the feasibility of it. We were actually to a certain extent inspired by the ARM mission saying, "Hey, if NASA is serious about capturing an asteroid in a bag, once we get it in a bag, there's a lot we can do with it from an asteroid mining perspective." So ARM was an inspiration to us and I was honored to actually have been selected by NASA to serve on the advisory board for the ARM mission.

Joel Sercel: Normally NASA planetary missions have science advisory boards. In this case, it was a science and technology advisory board. So there were a couple of us technologists on the board and it was a lot of fun. It was a great group of people. The people who ran ARM were doing, I thought, a terrific job and it's too bad that that mission was canceled. But it certainly was an inspiration to us.

Mat Kaplan: Now let's turn to optical mining that you've mentioned a couple of times. You get a bag around a good sized asteroid, one that looks very promising, lots of nice volatiles hiding away inside. How do you get that material out? What's the optical element in this?

Joel Sercel: That's a great question. So it's been known for many years that if you take highly concentrated sunlight or it could be a laser, but lasers are much more expensive and heavier. So in space, there's lots of sunlight. We'll talk about that in a minute. But if you take highly concentrated sunlight and focus it to a point, you can achieve extremely high temperatures. Theoretically, temperatures approaching the surface temperature of the sun in practical terms, probably about half that temperature. So let's call it 2,500 degrees Kelvin.

Mat Kaplan: Not bad.

Joel Sercel: And if you put a rock or lots of different type of ceramic material at that focus, it'll fracture, it'll break. The thermal shock will break it to pieces. And we call that process spallation or spalling. And it occurred to us that if we were to design the right optics assembly, we could create a large, very lightweight inflatable reflector that would concentrate sunlight inside the bag. And it's hard to describe it in radio. But if I had a whiteboard and that could make a sketch, it would be a lot easier.

Joel Sercel: But let's just say that there's a collection of tubes and mirrors and lenses. Some of the mirrors have to move in this process. We've shown through design and analysis, and we're going to prove it with our Mini Bee tests here shortly, that you can concentrate sunlight inside of a bag. And when that sunlight hits the surface of the asteroid that's contained inside the bag, it'll fracture it, spall it, break it into little pieces.

Joel Sercel: And what's really cool is those little pieces as they move away from the surface of the asteroid that they were just broken off of, they're in that very intense solar beam. And they heat up to very high temperatures very quickly, typically in a fraction of a second. When you heat the materials that these asteroids are made of, they release water, carbon dioxide, and other volatile materials.

Joel Sercel: So then what you've got is you've got a bag with an asteroid that you're drilling a hole in and gases are being released inside that bag. So you need to seal the bag, not perfectly, you don't need to seal it as well as a birthday balloon. And you just want to make sure it doesn't have a lot of big holes in it. And the gas starts to collect inside this bag. Now the gas is at a very low pressure. People imagine that as the bag is filling with these volatile materials, it's going to pop.

Joel Sercel: But in fact, the pressures that we would operate the bag at are about 1000 times less than the pressure here on the earth. In fact, we want to keep it less than 1000th of an atmosphere. But at that pressure inside the bag, we have a large hole in the side of the bag with a conduit that leads to a cold trap. A cold trap is a surface that you keep very cold. In this case, it only has to be colder than the freezing temperature of water, which is zero degrees centigrade, 32 degrees Fahrenheit.

Joel Sercel: And then the water vapor will then collect on this trap as frost. So you're essentially pumping the water vapor out of the primary bag into the secondary container using the laws of thermodynamics. And that secondary container can also be a thin film bag. And in fact, we've calculated that the secondary container that can hold 100 tons of ice can be a thin film bag with a special surface coating that keeps it very cold in space.

Joel Sercel: And we can store up to 1000 tons of ice in a thin film bag that only weighs a few hundred kilograms and is just a few meters across. Let's say the Honey Bees spacecraft flies to an asteroid that weighs 1000 tons about the size of a single family home. The Honey Bee spacecraft itself is about as massive as a large pickup truck. It captures the asteroid and mines about 1000 tons of water out of it. To get an idea of what 100 tons of water is, I have a pretty small swimming pool in my backyard, and I estimate that my swimming pool has 180 tons of water in it.

Joel Sercel: So it's about half the amount of water in a backyard swimming pool. On the earth, a container that would hold that much water would be a big, heavy thing. But in space in microgravity, if you're storing it as ice, so you don't have to worry about leaks, it can be a thin film membrane about as thick as saran wrap in your kitchen. Then you have these bags of ice, which are structurally fairly solid. We bring that ice back to the earth moon system, where it can be converted to different types of rocket propellant and sold on the open market.

Mat Kaplan: When you talk about 100 tons of water, I guess what's really significant there, the water may be useful on its own, but you're also talking about something like 65 tons of hydrogen and 35 tons roughly of oxygen, right? And those are what you're going to sell to people?

Joel Sercel: That's right. So some of our customers want to buy lox hydrogen or oxygen and liquid methane. Others would just prefer to buy the water. So for example, we have an agreement with Blue Origin that they're interested in buying water from us in space because they want to make their own liquid oxygen, liquid hydrogen propellant. We see ourselves as a utility company that sells water rocket propellant, and in some cases, high quality electric power in space.

Mat Kaplan: Joel, I wish we could use that whiteboard that you mentioned, but that's not going to happen in this medium. So I hope that listeners will go to your website, the TransAsta or Trans Astronautics website. There is a terrific video there, an animation that shows your Queen Bee in operation. This is the really big version in this A-plus line. I note that in the beginning, it fits inside one of the SpaceX Starship nose cones. Obviously you're designing it to be a payload for that big rocket.

Joel Sercel: Well, yeah. It makes a lot of sense to design our system to work with the biggest rockets available, and also to work with the commercial rockets that are highly cost-effective. In the relatively short term, we're focused on the Falcon 9. In the longer term, we're focused on the new Glenn and the Starship. It's no coincidence that Jeff Bezos is the most successful businessman and entrepreneur in the history of the world. And Elon Musk is maybe the most talented and successful engineer.

Joel Sercel: These men know what they're doing. As we move into space, an industrialized space, it makes sense to go big. Industrializing space with little rockets and little systems, it's just not cost-effective. Mini Bee has a gross liftoff weight of about 200 kilograms, less than 500 pounds, let's say. And Mini Bees there is a tech demonstrator because we think that we have investors, a combination of government sponsors and investors who will like to have us fly that into space.

Joel Sercel: Then it makes sense to go to the Falcon 9 because the Falcon 9 is a pretty big vehicle and it's fully operational and very affordable by space standards. But in terms of our vision, we have to go big. Every time you get bigger in space, you're more cost-effective. We've looked at the design of the new Glenn and we've looked at the design of the Starship and we love them both. And we see applications for us flying on both.

Joel Sercel: In terms of asteroid mining, we want to go to the biggest asteroids that we can get, and that drives us to Starship. The vehicle that we would launch on the Starship, the Honey Bee weighs about 5,000 kilograms, a little bit more when you fill it with propellant. The Queen Bee, which we see as the ultimate asteroid mining vehicle has a liftoff mass of about 40,000 kilograms. And that's not into low earth orbit that has to be put on a trajectory that's getting it away from the earth. And the only vehicle that we see right now that's cost-effective for that application is Starship. So yeah, we're focused on Starship.

Mat Kaplan: Got it. How soon might we see the first of your Mini Bee spacecraft making it up above earth?

Joel Sercel: The engineers who are listening will know what a PDR and a CDR. Those are three letter acronyms that describe different levels of design. We've completed the CDR on the Mini Bee in the last few months. We intend to complete the design and test of the Mini Bee within the next 12 months. And within 18 months after that, we can be prepared to launch it. And it all just depends on how the fundraising and the proposals to NASA and other government agencies go. But we think three years is a very reasonable timeline for flying Mini Bee in space.

Mat Kaplan: That's pretty near term. In the meantime, I read that you've been doing testing on the ground in the lab using what's described as the world's largest light bulb.

Joel Sercel: Yes. The world's largest light bulb is a light bulb that you can buy from a company called Superior Courts, and it takes 32 kilowatts. Okay. So the 32,000 Watts of power to run this light bulb. And so compare that to your 100 watt bulb at home for the engineers and scientists in the audience will get a kick out of the fact that it draws 700 amps at 45 volts when it's operating.

Mat Kaplan: That's a pretty good electric band.

Joel Sercel: It produces about 15 kilowatts of light. And in our laboratory, when that light goes off of our water-cooled reflector and through our sapphire window, into our cryogenically cooled vacuum tank, we can put about five kilowatts of that light into a circle about two inches across. Now, even at that power level, it's a subscale miniature of the full power of the Honey Bee vehicle. It's optical reflectors. We'll put more like 2 kilowatts on target. So 40 times as much power.

Joel Sercel: So we can put about five kilowatts on target inside of our cryogenically cooled vacuum tank. And in there, we can put high fidelity, asteroid simulants, tens of kilograms, or maybe up to 100 kilogram miniature asteroids to study the science and technology of asteroid mining. We've had the optical mining test bed and operation in the lab for about 18 months now. We're constantly doing upgrades and improvements on it. If you go to our YouTube channel, Trans Astronautical Corporation YouTube, you'll find our YouTube channel. You can see videos of that in operation.

Joel Sercel: And there are various places on our website and on the web where you can see this thing working. It's really cool.

Mat Kaplan: We'll pick out one or two of those and we'll put them on this week show page of, along with your website, of course. Much more of TransAstra's Joel Sercel ahead including his audacious plans for mining the moon and his strong feelings about the ethics of humanity's expansion across the solar system.

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Mat Kaplan: I promised you we would get to that discussion of space ethics, but I have to ask a couple more questions about what you're up to at TransAstra.

Joel Sercel: Sure.

Mat Kaplan: For example, before you can capture and start to utilize an asteroid, you've got to find them and characterize them, make sure they're good candidates. You're doing some work in that area as well. And it hearkens back to a pioneer in California where you and I both live. A lot of people here grow up learning about Sutter's Mill. And you've got a project named after that gentleman.

Joel Sercel: Yeah, we do. I took my family up to Sutter's Mill a few years ago and was really inspired just to think how the discovery of gold in California led to the settlement of California, all the wonderful stuff we have in this state, we really see a gold rush happening in space. And one of the developments that will make it happen is being able to find and prospect thousands of near earth asteroids every year, small near earth asteroids that are ideal for asteroid mining.

Joel Sercel: Right now, the astronomy community can find asteroids deep in the solar system. They can find many near earth asteroids and they're very good at finding asteroids that are bigger than about 100 meters in diameter. And so for the larger asteroids, 100 meters in diameter, kilometer, diameter, that sort of thing, we know where more than 90% of the asteroids are. But we only know where a tiny fraction of the smaller asteroids, the five to 10 meter diameter asteroids, the ones that are targets for asteroid mining.

Joel Sercel: So we need a special telescope that can find these very faint, dark moving objects. We're very excited about the Sutter Survey and a new mission concept that we've come up with called Sutter Ultra. Sutter Ultra is a way to put hundreds of small telescopes in deep space on three carrier vehicles. And all three carrier vehicles can be flown into deep space on a single medium class vehicle, like the Falcon 9. They go into heliocentric space in a special orbit that we've identified.

Joel Sercel: We call a pseudo geocentric orbit where they circle the earth in deep space, but they're actually not captured gravitationally bound to the earth. And with Sutter Ultra, we've calculated that we'll be able to find, characterize, and track 350 times more asteroids every year than all of the world's telescopes are finding today.

Mat Kaplan: Good Lord.

Joel Sercel: We think this is very exciting. Now that sounds like an outlandish claim. So we wrote a proposal to NASA with that claim in it, and it's been carefully reviewed. We know that peer review on this as demonstrated that it has scientific feasibility. It's a very risky proposition technologically. We need to demonstrate it on the ground. And so the next step is to actually build a small working unit of this compound telescope type that we've invented and demonstrate that we can find and track asteroids from the ground.

Joel Sercel: And we'll also be able to help out with tracking other moving objects in space, spacecraft and that sort of thing that could be navigational hazards. So we're extremely excited about Sutter Ultra. We can start asteroid mining with just the asteroids that are known to science now, but to turn asteroid mining into a trillion dollar business, we need to vastly increase the number of asteroids that we're discovering that are very small and very easily accessible from the earth.

Joel Sercel: It turns out that the asteroids you want to mine are what we call highly Earth-like orbits around the sun. The earth goes around the sun once a year in a nearly circular orbit at one astronomical unit. Well, it turns out that of all the billions of asteroids in our solar system, there are tens of thousands that are in orbits that are very much like the Earth's orbit around the sun. They're just spread out around that orbit. Think of it as almost a ring of asteroids. It's a mathematical ring, if you will.

Joel Sercel: And those all have very low return velocities. Actually, it's easier to get back from them in terms of how much rocket propellant they require than it is to get back from the surface of the moon. Those are the ones that really make a lot of sense economically to mine. And we know where very, very few of those are. So Sutter Ultra will find hundreds of those every year. And it's key to turning asteroid mining into a multi-trillion dollar business in the near term.

Mat Kaplan: Do you see Sutter Ultra playing a role in something we talk about all the time on this show, planetary defense, where NASA is continuing to develop that bigger infrared telescope of its own known as Neo cam?

Joel Sercel: Yes. Absolutely. My collaborator on Sutter Ultra is professor Robert Jedicke from the University of Hawaii Institute for Astronomy. We have actually corresponded and talked to Lindley Johnson, who's the person responsible for that at NASA headquarters.

Mat Kaplan: We know him well.

Joel Sercel: That's great. And we've actually done some statistical analysis of how many potentially hazardous objects we would find. And we agree with Lindley's assessment, which is that from a scientific and technological perspective, this should work, but it's high risk and it needs to be proven. So we're writing proposals like mad right now to get the funding, to prove this technology.

Joel Sercel: And we think it's a very compelling case. We think it's very solid technologically and scientifically. So we think we're going to get the funding to do that. And I'm looking forward to being able to tell the world that we've built a prototype of the telescope here on the camp ground demonstrated the basic technology so that we can get ready to fly in space.

Mat Kaplan: Before we leave the realm of the asteroids, I got to ask you, because we just, in fact on this show, we've been covering the encounter between the OSIRIS REx spacecraft and asteroid Benu, Hiyabusa2 is on its way back with a sample from Ryugu. There are other great missions, of course, like Rosetta. As you've seen these up close and personal views of asteroids and comets, has it given you greater encouragement? How has it affected what you hope to accomplish with TransAstra?

Joel Sercel: We think it's very exciting. We've been watching those missions with great anticipation. Congratulations to the teams that have had these wonderful successes. Whenever you get to new planetary body, there's some scientific theories that are confirmed and some that are disproven. In our work on asteroid mining, we've worked very hard to make sure that the technologies that we're working on will work regardless of the physical form of the asteroids that we contact.

Joel Sercel: In asteroid science, sometimes people talk about sandcastles or rebel piles or monoliths, and we've actually tested optical mining on simulants that represent that whole range. And optical mining is always designed to be able to handle that whole range. It's always better to have more characterization of what you see, because then you can design a little bit more narrowly. We love seeing the results from those missions. They're basically confirming that the physics is within the range of what we've been designing for.

Mat Kaplan: Joel, I hate to do this to you because it's another topic that deserves an entire conversation of its own. But last year at the NIAC symposium, I was there as you made a presentation about mining, not asteroids, but the surface of the moon, specifically those permanently shaded areas of the poles within the rims of craters. And it was utterly fascinating how you're going to pull that off. Can you give us a thumbnail, sort of an elevator speech description of what you have in mind for the moon?

Joel Sercel: Sure. We have two significant innovations that we're working on for lunar mining. The first is something we call radiant gas dynamic mining, which uses microwaves RF and infrared, and it goes into a mining vehicle, a Rover that we call the beetle rover. So beetle rovers will be large, domed Rovers that trundle across the lunar surface. When they get to a place where there's likely water, they drop the dome down onto the surface.

Joel Sercel: And then we use a combination of radio frequency, microwave, and infrared to heat that soil, that frozen soil, that icy regolith to sublimate the water and other volatile compounds that are trapped there. And then we have a patent pending invention that we call a cryo belt that is a continuous flow cryo pump that where the frost forms on this belt and then the belt carries it to where it's stored in a container. So the beetle rover we think is the key to being able to mine vast quantities of icy volatiles from large surface areas on the moon.

Joel Sercel: We're very excited that the NIAC office has selected us for a phase one NIAC, which I think you saw the presentation on. And now we're about halfway into our phase two. And so in my laboratory, we're building a high powered microwave system. This is in collaboration with Paul van Susante at Michigan Tech University. He has a large cryogenic vacuum tank called the dusty thermal vac chamber. And we're actually going to put a sub-scale version of this dome.

Joel Sercel: The real operational domes will be five meters across designed to fit in Blue Origin new Glenn vehicles. But we're going to do a dome that's more like a 1.2 meter, about four feet in diameter. And we'll be pumping several kilowatts of microwaves into one ton frozen lunar regolith samples to demonstrate how we can sublimate the water and other frozen volatiles and collect them. So we're very excited about that. We're doing it as a rapid one year phase two NIAC so that we can go fast to support the Artemis program.

Joel Sercel: An innovation that I'm even more excited about. Something that we call Sunflower. The thing about the beetle rovers is that they'll require lots of power, lots of electric power to heat up all that ice and collect it and liquefy it and all that sort of thing. We had a crazy insight about the moon. I like to ask people how tall of a tower do you think you could build on the moon?

Mat Kaplan: Yeah. You asked that very question in your presentation last year. And the answer was I have to admit surprising and you illustrate this at the website.

Joel Sercel: Yeah, that's right. So here on the earth, there's extreme limitation on how tall you can build towers and mass and that sort of thing, because we live on a 1G gravity planet, and you have to deal with wind and weather and all that sort of thing. But it turns out using today's materials, not anything exotic, we've calculated that you can actually make a package that you could land on the moon. The package lands on the moon as a self-contained unit, it opens up, and it directs a tower out of that package using a type of structure called a tensegrity structure.

Joel Sercel: Buckminster Fuller is credited with the invention of tensegrity structures. They're the most efficient structural form in nature. And we've calculated that you could actually build a tower this way on the moon, more than a mile high. And of course, if you make a mile high tower, it can't carry too much payload at the top. But if you make a tower that's less than that, a half a mile or a third of a mile, it can actually carry a significant payload on the top of a tower.

Joel Sercel: In fact, a tower that's 800 meters high can carry about 30% of its mass on the top of the tower. And you say, "Well, why do you care about building a large tower on the moon?" Well, imagine that you're near the lunar North Pole or the lunar South Pole, where is the sun? The sun is almost always right near the horizon. If you think about the local topology, if you're in a depression, the sun never goes into that depression.

Joel Sercel: It's those depressions that have not seen sun for billions of years. And that's where scientifically, we think there's billions of tons of water on the moon. So what if you could land one of these packages in a shallow indentation with modest topography that hasn't seen the sun for three billion years and erect a tower like this? The tower goes up and the top of the tower is in perpetual or near perpetual sunlight. This solves a critical problem that we've had in terms of long duration lunar exploration, how to power things on the moon.

Joel Sercel: Even on the equator on the moon, it's always been a challenge to think of how you power technology on the moon. Because on the equator, you get 14 days of daylight and then 14 days of night. How do you store the energy for all that time? We've always thought, well, the best place to be on the moon is the equator. You get the most power, the most sunlight, but it turns out that may not be the case. It may be the case that you're better off going to the poles erecting towers.

Joel Sercel: And then at the top of the tower, you put a solar reflector, a lightweight, thin film, solar reflector, cast that sunlight down to the surface. And then you can have fairly ordinary solar panels at the surface that can produce power. Our calculations suggest a single new Glenn launch can put up what we call a Sunflower. Sunflower is an integrated tower with a reflector on the top with a heliostat that causes the reflector to track the sun as it goes around once a month and solar panels on the bottom.

Joel Sercel: A single new Glenn launch can put a Sunflower on the moon that can produce a megawatt of electric power. A megawatt of electric power's a lot of power, is enough to power a good sized neighborhood or small town here on the earth. And it's enough to power the beetle rovers. And so together, we put the Sunflower towers, the beetle rovers, and an architecture for a lunar outpost that does water mining. And we call that the lunar polar mining outpost. So we're studying that under NIAC funding in collaboration with our friends at Blue Origin.

Mat Kaplan: You have to see it to believe it. It is audacious and quite comprehensive. You can see it on the TransAstra website. Joel, I'll have to share with you someday the interview that I did with Bucky Fuller not long before he passed away. I think he'd be very proud to know that 10 segregate is being proposed for the polls on the moon.

Joel Sercel: That's fantastic.

Mat Kaplan: I didn't want to cut any of this short because it is so fascinating, but let's get onto that topic that you actually proposed to talk about in this conversation. And that is space ethics. And I'm not exactly sure where you want to take this, but I've got a question. And that is whether you are a fan of The Expanse, that series of great science fiction books, which has been turned into a TV series, which now to give Jeff Bezos another plug is on Amazon Prime. We're waiting for the next season to show.

Joel Sercel: I'm a big fan of The Expanse. I started reading the books in The Expanse long before the TV show came out. And as you know as a fan of the show, it's a story that takes place a few hundred years in the future where humanity has spread throughout the solar system. And there are sort of three contingents. There are the people from the earth, they're the Martians, and they're the Belters. In The Expanse, the Belters are an oppressed group. Maybe the reason you're asking about space ethics in the context of how the Belters are treated in The Expanse.

Mat Kaplan: Exactly right.

Joel Sercel: It's things like the way the Belters are treated in The Expanse that gives me pause and makes me want to stop and say, "Hey, obviously I've devoted my life to the idea of humanity moving into the solar system and learning to harness the resources of the asteroid belt." I am an O'Neilian, Gerard O'Neil gave me my first ever private consulting contract, working on beamed energy rocket propellant, propulsion, actually. And so I've been a big fan of the idea of building worlds out of asteroid material and harnessing those resources for the betterment of humanity.

Joel Sercel: In the time that I've been here on the earth, I've had a chance to read a fair amount about human history and you see that human beings are fundamentally, as we came up as hunter gatherers. We are wandering people. During most of the evolution of humanity, people lived in small villages that were always on the edge of a frontier and on the edge of the frontier is where we're sort of designed by nature to live. And it's a real problem that here on the earth, we're out of frontiers.

Joel Sercel: And one thing that space can give us is a frontier that's incredibly important. And if you look at the paleolithic record, if you look at the prehistorical record, and historical record, what you see is that as humanity moves from one habitat to another and expand, its net, net good for humanity, it's very important that we do this. However, as you look at the historical record, as humanity has moved and colonized different parts of the planet, it's always been a reflection of the sort of moral and ethical maturity of the species at the time.

Joel Sercel: I'm a big believer that the species is getting better. As a species, we did things in prehistoric and historic times that are worse than what we do today. We're getting better. And we need to demonstrate that we really are getting better. As we've gone into new territories in the past, what have we done? We've moved into new ecosystems and brought pests from our old ecosystems that have damaged those local ecosystems. We have brought disease and pestilence that has caused the collapse of civilizations.

Joel Sercel: We have done it in such a way where we had competing powers competing for real estate and resources that led to war. And we have not been good stewards of the environment. So the question is, how can we learn from that? And how can we do a better job in the high frontier? I'm trying to, whenever I get a chance, to talk to people about, yes, let's lean forward aggressively, let's bring free markets and enterprises into space. But let's learn from the mistakes of the past and establish a field of endeavor that I call space ethics.

Joel Sercel: Space ethics is modeled in my view to some extent on bioethics. Bioethics, like any other human endeavor are not perfect, but boy, am I glad that we have bioethics? Bioethics are what give us staged trials of medications. It doesn't always make sure that even after stage three trials, medications go to market that are still imperfect because science is an imperfect process, but it's saved millions and millions of people.

Joel Sercel: The reason bioethics work is because within the biological community, if you don't follow bioethical standards, no one in the community will cite your work. In order be a worker in the community, you need to follow those standards to the betterment of humanity. It's because of bioethics that people aren't selling their kidneys for transplants. Without bioethics, there are billions of poor people in the world today who would give up vital organs for the money. These are very important considerations.

Joel Sercel: People who haven't had a chance to look at bioethics may not be aware that the bioethics protocols that we've evolved to as a people actually came out of the Nuremberg trials after World War II. Both Nazi Germany and Imperial Japan did what would by today's standards be considered highly unethical experiments on prisoners of war and people in concentration camps. And they made a lot of scientific progress and the science community said, "No, we won't accept this. And we won't cite it because we won't encourage other people to do it."

Joel Sercel: So let's do a great job of being ethical as we move forward. We need to bring bioethics into space. Let me give you an example. This is a very complex technical subject. I'll try to put it in a nutshell, it won't give it fair treatment. One of the really hot areas in biology today is called epigenetics. Epigenetics is the process of offspring inheriting traits or other characteristics from their parents that are not encoded in the DNA but are instead encoded in a methylation and other marks on the DNA and other aspects of gene expression that are a function of what that parent did in their life.

Joel Sercel: Do they have a healthy diet? Now we've seen epigenetic evidence of starvation in a population that affects the phenotype. Phenotype is how you actually look as opposed to your genotype, which is what's encoded in your DNA. And we have solid scientific evidence that starvation events have a phenotypic implications, at least three generations hence. So would it be ethical to put millions of people in a city on Mars where Mars has a significant radiation environment?

Joel Sercel: The whole planet is covered with perchlorates, which are known poison, and we don't know what the multi-generational impact of reduced gravity would be. And there's good reason to believe that it would have significant epigenetic effects. Actually, the way the Belters are really tall and thin and weak in The Expanse, that is actually something you might expect as an epigenetic outcome of microgravity. It might be that multi-generational living in a high radiation reduce gravity environments actually makes offspring non-viable.

Joel Sercel: So bioethics is something we need to bring into space. And there are three or four others that I'll just list off real quick. Another is what I call stewardship, making sure that when we go into space, we don't mess up where we're going for future generations. We don't do things like create excessive light pollution. And by the way, I think the scare over light pollution in the Starlink constellation is exaggerated, but we need to take a careful look at things like light pollution in lower earth, orbital debris.

Joel Sercel: When we go to the moon, as we're landing on the moon, we need to make sure that we don't destroy the environment. Take so much water out of the moon that that resource is gone for future generations. Just be good stewards of the environment in ways that humanity didn't necessarily always do in the past, at least judged through the ethics of our age. Human rights, this is the one that you were, let me riff on that from The Expanse. I just read something on Twitter.

Joel Sercel: Someone posted an excerpt from the Starlink user agreement in SpaceX. I don't know if this is true, but it was posted on Twitter, a screen grab of the Starlink end user agreement. And it says if there's a legal dispute and it has to do with use of Starlink in earth orbit or around the moon, then any disputes will be settled using California law.

Mat Kaplan: We should mention that Starlink as a lot of our listeners know is the massive network of satellites, thousands of them that Elon Musk and SpaceX are launching, are establishing this mesh of satellites above the earth, lower earth, orbiting satellites to further communication. And that have at least an extensively worthy goal of bringing high speed internet to areas of our planet that don't have them. There is that side of the moral equation as well.

Joel Sercel: I'm a huge fan of Starlink. I think it will be a tremendous boon to humanity. In the Starlink user agreement that Bob Zubrin posted on Twitter last night, it says that if there's any dispute in Mars, then that'll be up to the Mars authority and you have to use Martian law, whatever that is. So does Martial law respects human rights? Elon Musk seems like a good guy. So probably would. But what if it's Chinese Martian settlement? What is their take on human rights?

Joel Sercel: We need an international standard that says the human rights of the enlightenment, the ones that we're endowed with at birth that have to be defended and not taken away, have to be defended in space also. Bioethics, human rights, stewardship none of those will work without the rule of law. Finally, we have to develop international standards that don't lead to war and that don't encourage war and conflict.

Joel Sercel: Humanity has always brought war and conflict wherever It goes. I'm a huge fan of humanity. I'm a humanist. I love the human species, but we're not perfect. And we bring more where we're going. Let's do this in such a way that it doesn't encourage conflict. I actually think NASA has taken a really nice step in this direction with the Artemis Accords. Are you aware of what the Artemis Accords are?

Mat Kaplan: Yes, just signed off by our European partners in the last few days where we'll be doing additional coverage of this in the coming weeks here on Planetary Radio.

Joel Sercel: The Artemis Accord's this wonderful agreement that NASA has put together that embraces some of the principles that I'm talking about, but not all of them, signed off by partners, international partners to sort of make sure that some of these things are in place. But there really hasn't been an international discussion about what the accord should be the equivalent of the Mayflower pack for space.

Joel Sercel: And the thing about it is, is we live in a global village now. These technologies are so powerful that they affect everyone. One of the principles of bioethics is that before you do a biological experiment that could affect people or a population, you need to consider and actually have people from that population included in the ethical discussion before you approve the experiment. So for example, this is one of the reasons why you can't do phase three trials or phase two trials on a population that won't get access to the medication that comes out of that trial, is because they're stakeholders.

Joel Sercel: So there's a concept of the ethical implications on stakeholders. So there hasn't been a stakeholder engagement in the space business. It's time for it to start happening because we want to move fast and we want to do great things in space, but we don't want to be slowed down. Two particular items of recent interest that worry me a little bit about this. One is an interesting essay written by Rick Tumlinson, who was the founder of an asteroid mining company, Deep Space industries.

Joel Sercel: And he's written an essay called the Elysium Effect named after the Matt Damon movie Elysium. In that movie, billionaires build colonies in space where they lived in splendor and the people of the earth lived in squalor. Rick's concern here is that with the billionaires and the wealthy countries working on the space problem, it'll create a jealousy syndrome such that the rest of the world will do what they can to stop it.

Joel Sercel: I think that's maybe a little paranoid, but how crazy the world is these days, maybe being a little paranoid is a good idea. Why not engage them in a conversation and try to bring them along as partners? Clearly I, and I'm sure Jeff Bezos and Elon Musk and I'm not putting myself in their shoes, but people who work in this field we're in it because we think it will be for the betterment of humanity. Let's make sure that we do it in such a way that it really is, and let's make sure that we engage with the stakeholder communities, such that they see that it's really for the best.

Joel Sercel: We come in peace for all mankind as we say. One other point, a group of scientists recently wrote an essay about the Artemis Accords and talked about how it wasn't fair, too much emphasis on free markets and that sort of thing. I can get you a link to that if you're interested.

Mat Kaplan: Please, yeah.

Joel Sercel: But it's the kind of backlash that can happen if you don't really think carefully. Before you build a constellation in space, maybe you should think about its effect on astronomy rather than wait until you've launched the first few satellites and then say, "Oh, well, maybe we can paint them black." As an advocate, the guy who wants to go super fast, I think the best way to go super fast is also to stop and think and have a serious conversation about space ethics.

Mat Kaplan: Joel, this is a conversation that we should continue sometime. I hope you would be up for that. Maybe we bring in some other people who think about these things as they help us move forward across the solar system. People like Rick TUmlinson, who you mentioned and others. It is reassuring to hear someone who is laying the technological basis for this expansion, who is also considering how we avoid the mistakes that humanity has made so often almost universally in the past.

Joel Sercel: Well, thank you so much for having me. I've wanted to do your show for so long and I'm really honored to be here. And it's just been a delight to get to chat with you about these things that are really the motivation for my life.

Mat Kaplan: Well, we'll do it again, I hope Joel, and before too long. I got to close with this. I think we share affection for a quote from the great Alan Kay, the guy who largely invented the graphical interface used by all PCs and Macs. Do you know the one I'm talking about?

Joel Sercel: The best way to predict the future is to invent it.

Mat Kaplan: That's the one. Thank you, Joel. It has been a delight to talk with you. We'll do it again.

Joel Sercel: Fantastic. Thank you so much.

Mat Kaplan: Joel Sercel is founder and principal engineer at TransAstra. Bruce Betts is coming right up. Time for What's Up on Planetary Radio. So here is the chief scientist of the Planetary Society. That's Bruce Betts who's ready to tell us about the night sky and probably a bunch of other stuff and maybe offer us a new trivia question. I'll settle for What's Up. How are you?

Bruce Betts: Hunky-dory spiffy keen swell. How are you?

Mat Kaplan: All of that and more in spite of it being the day after the election.

Bruce Betts: Well, we've got planet who don't really care about elections.

Mat Kaplan: Lucky them.

Bruce Betts: We've got Jupiter and Saturn in the evening sky's still over in the southwest, Jupiter's super bright, Saturn yellowish to its left. And I'm getting excited, even though it's several weeks away, December 21st, the two of them will be super close together in the sky. We'll keep talking about that. We've got Mars over in the east, southeast in the early evening and up most of the night.

Bruce Betts: It is fading, but it is still really, really bright and looking orange-ish. In the pre-dawn sky, Venus hanging on fairly low, but super bright. Can't miss it over in the east.

Mat Kaplan: December 21st, you say, that's what I should be looking forward to as well. And I am.

Bruce Betts: You can watch them closing on each other in the meantime like a very, very slow collision. But it's not even close to a collision. Because they're really far apart.

Mat Kaplan: My dogs are going, well, dog, my dog and the other two dogs are going absolutely crazy downstairs.

Bruce Betts: Okay. I'm sorry. It's probably because I told them about Jupiter and Saturn on December 21st. Dogs love conjunctions, little known fact. All right, we move on to space fact. More than 16 series, the smallest dwarf planet. If you took more than 16 of those would fit inside Pluto, the largest dwarf planet discovered so far.

Mat Kaplan: That's impressive. Because series is pretty sizable.

Bruce Betts: It is. It is. But it turns out even as the largest asteroid, it is much smaller than all of those big trans-Neptunian objects like Pluto and Eris. All right. So we move on to the trivia contest and I asked you about sample return. As of now, how many robotics spacecraft, emphasis on robotic, have returned samples to earth from the moon or beyond? How did we do, Mat?

Mat Kaplan: We had many great responses this time around. I'll give you one from Rennie Christopher up in been the state of Washington. Just six robot. Craft managed to bring their samples back to us on earth. He says, "My answer is a bad haiku. So I need a book of better space poems." You probably do Rennie, but I'm afraid we can't help you this time because our winner is Melanie [Podbioski 01:01:35]. At least I think she's our winner because she also said there are six successful sample return missions from the moon and beyond. Is that right?

Bruce Betts: That is correct.

Mat Kaplan: You want to run through them?

Bruce Betts: Sure. We've got the three Luna that's Luna 16, 20, and 24 from the Soviet lunar sample returns in the '70s. And then Genesis returning samples of the solar wind and such. Stardust, samples of a comet and Hiyabusa samples of an asteroid.

Mat Kaplan: Melanie, congratulations. You have won yourself that wonderful collection of poetry Beyond Earth's Edge. The poetry of spaceflight edited our recent guests, Julie Swarstad Johnson and Christopher Cokinos. It's from the University of Arizona Press. My copy is sitting next to me. It is full of inspiration. She's a long time listener, but a first time contest participant. She was really inspired by the poetry show. So fingers crossed that I will win the book.

Mat Kaplan: You can uncross now, Melanie. Here's more, Stephanie Latourneau in Nevada, six, hopefully seven soon. One can only hope to see more moon robotic recruit regardless of country, space exploration is always extraordinary. More and more poetic efforts. Hudson Ansley, New Jersey didn't know that Russia had tried to get a sample back from Phobos. He said, "That would have been interesting." You are all too aware of that project, right?

Bruce Betts: Yeah. The Planetary Society had our living interplanetary flight experiment or life onboard the Phobo sample return mission in 2011. But rocket problem, it came back and violently explored earth rather than exploring Phobos and the light and made the third Phobos Soviet or Russian mission I'd been involved with that failed. So I'm a little scarred.

Mat Kaplan: I think maybe they should not make you a part of the next one or maybe just give you a pseudonym or something. Maybe that'll-

Bruce Betts: Wow. I hadn't realized it was all my fault. Thanks, Mat.

Mat Kaplan: You're so welcome. Adding to that, John [Leyendecker 01:03:59] in Colorado. He soberly reports that even if Hiyabusa2 and OSIRIS REx returned their samples, fewer than half of the sample return attempts will have been successful.

Bruce Betts: Surprisingly enough, it's tricky to get samples out there in the solar system and get them back safely.

Mat Kaplan: Robert Klein in Arizona, scientists have yet to explain why the particles captured in the Aerogel. Was that Stardust or Genesis?

Bruce Betts: Yes. I mean that seriously, they both utilized Aerogel.

Mat Kaplan: I should have remembered that. Anyway, why the particles captured in the Aerogel have the same chemical composition as belly button lint? That is a puzzler.

Bruce Betts: Kind of a worrisome puzzler.

Mat Kaplan: Yeah. Also not true. Finally, this closing poem from Jean Lewin in Washington. Traveling by robotic means across our galaxy, returned samples of regular from our moon by Luna Missions 3. Three others ventured on different paths, varying in scope. Valiant explores gathered clues if I can use that trope. Hiyabusa2 an asteroid, a Neo like Bendu Stardust to a common designated vill two. With Genesis rounding out the three, it made a noble run collecting samples of solar wind or pieces of our sun. Nice work Jean. That's it. We're ready to move on.

Bruce Betts: All right. I discussed how many of the smallest dwarf planet would fit in the largest dwarf planet. Here's your question. How many of the largest dwarf planet Pluto would fit inside the smallest planet in our solar system Mercury? Assume that it can be deformed and there are no falling gaps, but no pressure squishing or anything like that. So basic volume to volume comparison. Yes. I feel I have to say these things.

Mat Kaplan: Okay. You have. Wait, you didn't actually tell people how to enter yet.

Bruce Betts: Well, if you want to enter, go to

Mat Kaplan: And who wouldn't want to enter and maybe win themselves? We'll do it one more time. At least a Planetary Society kick asteroid rubber asteroid. That's the price of this time. If you get it to us by Wednesday, November 11 at 8:00 AM Pacific Time, you will be eligible and that's it.

Bruce Betts: All right everybody, go out there and look up the night sky and think about what president, vice-president ticket you'd vote for if the president were a planet in our solar system and the vice-president where a moon. Thank you and good night.

Mat Kaplan: I was going to nominate the Betts Kaplan ticket for 2024.

Bruce Betts: Ooh, better idea.

Mat Kaplan: That's Bruce. He's the chief scientist of the Planetary Society. Future candidate who joins us every week here for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California, and it's made possible by its members who are always mining for space gold. Join these new era 49ers at Mark Hilverda is our associate producer. Josh Doyle composed our theme, which is arranged and performed by Peter Schlosser. Ad astra.