In this episode of C&EN Uncovered, host Craig Bettenhausen speaks with C&EN reporters Bri Barbu and Fionna Samuels about space science. The conversation delves into the geochemistry of the solar system, sustainability for interplanetary missions, and the present and future of human space exploration. Their articles are two parts of a four-part package on space.
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Executive producer: David Anderson
Host: Craig Bettenhausen
Reporter: Bri Barbu and Fionna Samuels
Video + Audio Producer: David Anderson, Jeremy Barr
Episode artwork: NASA
Music: Commercial Flow, Shutterstock
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The following is a transcript of the episode. Interviews have been edited for length and clarity.
Craig Bettenhausen: Welcome to C&EN Uncovered. I’m Craig Bettenhausen. C&ENUncovered is a podcast series from Stereo Chemistry. In each episode, we’ll take another look at a recent story in Chemical & Engineering News and hear from C&EN reporters about striking moments from their reporting, their biggest takeaways, and what got left on the cutting room floor. This episode, we’ll be taking a deeper look into sustainability and geochemistry. Seems like pretty run-of-the-mill C&EN stuff, right? Except today we’re talking about space. Specifically, where the planet we call home fits into the geochemistry of the solar system and how sustainability may affect our future interplanetary explorations. These two topics were part of a package of space articles that came out recently in C&EN, and we’re here with reporters Brianna Barbu and Fionna Samuels, who wrote two of the articles. We’ll put links in the show notes along with the episode credits. Hi, Bri. Hi, Fionna.
Brianna Barbu: Hey, Craig.
Fionna Samuels: Hey, how’s it going?
Craig: So, for anyone that hasn’t had a chance to read the article, can you give a brief overview of what it is and what your two pieces of it are?
Bri: I’ll let Fionna kind of introduce the space package as a concept.
Fionna: Yeah. We talked about potentially writing about space stuff, and you talked to Prachi [Patel] about writing about space stuff, and then we all came together because we realized that all of our beats actually could be applied to chemistry and space stories. So when I say all of our beats, I do mean the entire Physical Sciences team. So along with Bri and myself, we have Prachi Patel and Ananya Palivela, [who] also wrote stories for this package. So there’s four stories in total, one from each of the Physical Sciences reporters, and each story is, like I mentioned, the intersection between our Earthbound beats and space. So I wrote about the geochemistry of a few interesting places in our solar system and how scientists are using these far-off places to understand more about Earth. And then Bri, if you want to talk about what you wrote.
Bri: I wrote about how materials, chemists, and engineers are thinking about sustainability and material circularity when it comes to human space travel to the moon or Mars. And there’s a whole backstory that I’m sure we’ll get into of how I ended up on that topic.
Fionna: And then in addition to our two stories, our colleague Ananya wrote about how we’re actually going to get to Mars because that’s a whole to-do. And then our colleague Prachi wrote about how we’re going to feed everybody in space.
Bri: Fionna, you can correct me if this is wrong, but I believe that the initial idea was somewhat pegged to the Artemis II mission that happened in the spring of this year, and we were thinking about how to capitalize on the excitement.
Fionna: I think you’re spot on. The package as a whole definitely came out this year because of the Artemis mission. Obviously, in April, this was the first time that we sent humans back to the vicinity of the moon. The last time we were there was Apollo 17. That was the very last mission to the moon with people, I should say. And that was in 1972, so quite a while ago. So it’s nice to have missions going back to the moon and soon, hopefully, landing on the lunar surface with people. And then maybe we’ll write a whole new package when we actually put people back on the moon.
Part of the whole Artemis mission, people were really excited to hear what the astronauts were seeing with their eyes because I guess there’s colors and things that are more easily perceived by people than by instruments. And so when they were seeing all those little impacts from asteroids hitting the moon and they were seeing little sparks of color, not necessarily luminescence, but just some sort of colorful thing, that was something that folks were really excited about. Researchers were really excited about, I should say.
Craig: So Bri, I mean, I know organic chemistry is in everything, but it is a little bit—this materials science recyclability is outside of some of your most common footsteps. How did you end up with this story?
Bri: So the very first seed of the idea actually came from a source that is not quoted in the final piece. And it came out of a story that I wrote about mattress recycling, where I talked to a polymer chemist named Jeff Long, who works at the University of Arizona, about how to recycle polyurethanes. And I think we did an Uncovered about that story as well, which is a nice sort of full-circle moment. But the first seed of what would actually become this story was from the 2025 Fall ACS [American Chemical Society] meeting. [ACS publishes C&EN but is not involved in editorial decisions.] I went to a symposium that was cohosted by the Polymer Science Division; Katrina Knauer was speaking. So I ended up in this NASA symposium. People were talking about the future of space research post ISS [International Space Station] because they’re decommissioning the ISS, but they also were talking a lot about the science that we’re going to need to send humans to Mars and the moon.
So I filed that away as well, as the seed of a future idea. I was like, OK, one day I’ll write a story, and I’ll talk to Jeff and I’ll talk to Kat, and it’ll be about sustainability in space. So when we started talking about this space package, I reached out to both Kat and Jeff in December and asked them some very broad questions about: What is sustainability in a space context? How does Europe address this? Who else is doing cool work in this area? And they both gave me very different answers, and I sort of ended up pursuing two different but parallel lines of research over the next few months. Jeff and the folks he referred me to were mostly academics, and they were talking a lot about engineering, circular manufacturing, and repairs in space for satellites, and how to avoid or cut down on space debris and atmospheric pollution from space debris, which was really fascinating and obviously has to do with sustainability.
And Kat, she’s doing food packaging and stuff related to human space travel and being able to effectively maintain a base on the moon or Mars or wherever because you can only send a limited amount of matter to space with you. And so if you want to be up in space long term, you have to learn how to manage basically every single atom that you send to space. You have to be able to manage and know this does that, you know: you’re reclaiming your pee to drink, you’re recycling your carbon. So I had these two parallel sort of lines of research and it became clear as we were talking about the package that I could only kind of choose one and I was more personally and scientifically interested in humans going to the moon. And also obviously we had that news hook with the Artemis II mission and future Artemis missions set to land humans back on the moon in a couple of years and build a moon base by 2028 or 2030 or something—
Craig: It’s an aggressive timeline for the moon base.
Bri: —unreasonable like that. Half of my reporting, literally half of the people that I talked to for this story are not quoted in the final piece because they were talking about satellites and space debris, and I decided to just focus on human space travel.
Craig: Hitting that feeling is part of why I pitched Uncovered to begin with because like, oh, the person that gave me this article is not in the article. That was the genesis of Uncovered was that kind of feeling. So I’m with you on that.
Bri: And so I wanted to say one more thing about organic chemistry in space, which is that your traditional synthetic organic chemistry with solvents and fume hoods and stuff, it’s not going to happen in space. So you’re actually using biology to do the kind of organic chemistry in space. So if you want to synthesize drugs and medicines, you’re actually going to have to engineer some microbes and enzymes for that. You’re not doing a black-walled hardware coupling in space.
Craig: I mean, sustainability is an interesting term because it’s very different. And when we talk about sustainability on life on Earth, it’s a little bit of a different conversation than sustainability of a moon base or a Mars base. Can you talk about the contrast between those two different kinds of sustainability?
Bri: Yeah, I think that was the most fascinating thing for me as I was looking into this idea was getting, talking to so many people and getting so many different people’s definitions of sustainability back. And it was really the first question I had to ask everyone was, What does sustainability mean to you? Especially because obviously a lot of the researchers that I talk to come from government labs, and certain terms are a little bit more politicized. During the reporting of this story, the National Renewable Energy Laboratory changed their name to the National Laboratory of the Rockies. But it really comes down to, you have to look at the word. Sustain is part of sustainability. We want to sustain a human presence on the moon or Mars, and you have to think very carefully about how you use your matter for that purpose. And if you really think about the basics, it’s the same way on Earth: you have to be mindful about where your matter goes. But really it’s about materials efficiency. It’s about thinking about what your resources are and where they should go and not wanting to waste anything.
Craig: Fionna, your part of it took a literally further look far out into space talking about the chemical composition of other bodies in our solar system: water on the moon, minerals in asteroids. But as Bri mentioned, extracting materials from minerals on Earth involves huge energy-hog equipment. Are the Mars colonization people, and other people, are they planning to send all that machine mass into space or what are they doing with the information that they’re learning from the research you talked about?
Fionna: Oh, man, that’s a good question. In terms of how our future Martian astronauts will use the resources on Mars, I’m not sure. And I don’t think that anyone’s really sure yet, because we need to have a really solid understanding of what sorts of in situ resources there are for various bases. So even on the moon, when we’re thinking about a moon base, I believe that NASA is considering putting the moon base on the South Pole specifically because there is water ice on the South Pole, and they think they might be able to use it to do stuff.
So knowing what’s out there is incredibly important for future missions, but it’s not just about sending people to places. It’s also about understanding how various bodies in our solar system arose and then being able to look even more distant into the cosmos and find or understand how solar systems that are nothing like ours might have evolved and potentially look for habitability and stuff like that.
Because I mean, Earth is incredibly unique. And if this story indicates anything, I think it is that Earth is incredibly unique.
Craig: Is that push and pull between using what we learn on Earth versus becoming a multiplanetary species, do they have camps that some people are doing the research for one or the other? Or everybody thinking about both? What’s the interplay between those two ideas—in the people you’re talking to, at least?
Fionna: When I talk to the people, they are really focused on understanding the solar system almost for the sake of understanding the solar system. And a lot of the research is with the hopes of helping future missions or current missions. So one thing I didn’t have the opportunity to talk about in my piece was Mercury. We know very little about Mercury, but it’s actually a pretty interesting planet. We’ve only sent two missions there, and there’s a third mission on its way right now. And so one of my sources, Michelle Thompson, who did all of the work with airless bodies and weathering of airless bodies, her current research is also involved in looking at how Mercury might weather because Mercury doesn’t have a lot of iron on its surface. And so obviously bombarding a planet without iron is going to have a different effect than bombarding a planet with iron.
And when I say bombardment, I mean small particles hitting the surface. Anyway, the point is that her motivation is to be able to use what she learns in lab for this really unique mission to Mercury so that we can better understand what we’re actually seeing when the spacecraft is orbiting the planet. And I don’t think that there’s currently any greenlit mission to land on mercury. And that’s sort of the point of a lot of the research that I looked at is because it’s going to be really rare to have a lander land on one of these planets, even in our solar system. So connecting lab experiments to the very few extraterrestrial samples that we do have so that we kind of understand how observations from afar connect to something that we can hold, we make that connection, then we can make that connection when we don’t have the samples that we can actually touch.
Craig: As we as a species are making plans right now for sustainable outposts on the moon and Mars, we’re also advancing plans to shove most of the International Space Station out of orbit so it gets destroyed while reentering Earth’s atmosphere. Why can’t we at least salvage the ISS for parts? Why are we just going to toss it into the ocean after burning it?
Fionna: I will not claim to be an expert, but I looked at it very briefly. I just think that it’s going to take a lot more resources. So there are two camps with the ISS. There’s the camp that says when we decommission it, we should just let it fall into the Earth’s atmosphere. Some portion of it will burn up as it enters the atmosphere, and then some portion of it will actually end up in an ocean, probably the Pacific. And then the question is should we try to salvage what ends up in the ocean for whatever reason? There’s another camp that says this is a modern marvel. This is amazing. We shouldn’t let it burn up into the atmosphere. Let’s send rockets up there and basically boost it up so it’s higher in orbit because everything that is orbiting the Earth at low Earth orbit altitudes is slowly falling into the atmosphere.
It’s being pulled in. So inevitably satellites are going to fall and burn up in our atmosphere, which is probably something that Bri’s . . . I think that it just comes down to money. It’s easier, more straightforward, less expensive to just decommission it in that way rather than trying to boost it back up so that it’s going to take longer to fall into the Earth’s atmosphere.
And I think that the reason they’re decommissioning it is because it’s just kind of out of date at this point, and they keep having leaks. It’s kind of like having an old car. At some point you need to decide whether or not it’s worth reinvesting a bunch of money to keep the repairs and just keep the car running or to buy a new one. And no judgment. I feel like I will be very sad when the ISS is actually decommissioned because it is a marvel and it’s amazing that we’ve been able to send people up there and people have been able to live on the ISS for hundreds of days.
It’s amazing, but it’s also old.
Craig: Well, and the international collaboration on the ISS has been another sort of marvel on its own. I mean, even through the worst conflicts, the US, Russia, and China were collaborating on the ISS to wonder in that regard too. I mean, what have scientists and engineers learned from the 25 years of humans living on the ISS that they’re applying to the Mars and moon missions that you all were exploring?
Bri: I do not have a comprehensive view of what all they’re learning on the ISS, but I know there’s a lot of interesting preliminary work for the stuff that I wrote about in my story that has happened on the ISS, like the engineering microbes to produce vitamins. For example, there’s a whole bunch of synthetic biology research going on in the ISS, which will hopefully enable us to figure out how to do chemistry in space, really. They’ve sent material samples up to the ISS to test their weathering and such and their recyclability and their various properties. But there’s only so much that you can do on Earth. You do have to be able to send these samples of new materials or new chemistries up to space. We’ve sent a lot of stuff to the ISS. Kat sent some biodegradable polymers to the ISS. Allison Christy, who’s another major source of mine, has sent some of her regolith polymer composites, I believe, to the ISS.
Fionna: The ISS is one of the most accessible places in space for research of all of the places in space that we have access to. And so NASA, whenever they’re sending up refueling missions, and other space agencies, there’s an opportunity to send a science mission or a science research project up to the ISS. So you get some idea of what will happen in that radiation environment. You’re not protected by the atmosphere. You get some idea of how your research will be affected by microgravity. Yeah, so I think that Bri’s right. A lot of people try to send their stuff to the ISS before putting it—we don’t even have a moon base yet. Well, and one of the things about the current moon stuff, the lunar missions that have not involved landing people on the moon, but have involved landing landers on the moon. They do have science projects on them, but at least for the NASA programs, the CLPS [Commercial Lunar Payload Services program], it’s the public-private partnerships for these lunar missions.
The landers are not always successful. And so then you’ve put in blood, sweat, and tears to get your research project to the surface of the moon, and you can’t get any data from it because the lander tipped over or is nonresponsive or whatever. And there’s no guarantee that you’ll be on the next mission.
Craig: So what are the big unsolved material science challenges for extraterrestrial habitation?
Bri: I mean, I think dust-resistant materials are a big one. I was much more focused on “Here are the things that we can translate from the Earth to the moon that I’m familiar with.” But I think it’s a lot of actually instrumentation that we want to be able to have on the moon so we can study the moon or Mars, because the moon is, in the minds of many people who are planning for such missions, a stepping stone towards going to Mars.
Fionna: On that note, I do think it’s important to mention that the Artemis program is part of NASA’s Moon to Mars program. So it is literally a stepping stone, which is part of why they’re so invested in it at this point.
Craig: The Artemis program has gotten, it’s been changed around a little bit in the current presidential administration. It was defunded for a bit; it’s refunded. What next for the Artemis? They went around the moon, what’s the next one?
Fionna: This year has been a big year for Artemis. Obviously we had the crude mission around the moon. And then in March, right before that mission, Jared Isaacman, who is the NASA administrator currently, announced some pretty big changes to the program, and it’s all motivated to get us back to the moon as quickly as possible. But one of the changes was, I believe, changing some of the hardware that they’re going to be using. And so the next mission is going to be crude, but it’s not going to the moon. It’s just going into Earth orbit to basically test some of the newer hardware, just make sure everything is up to snuff. And then after that, I think Artemis IV is the next one that’s to the moon, and that is scheduled to land on the lunar surface sometime late 2028. So in 2 years, which is really exciting.
Craig: OK. So here’s an out there one. My friend Eric thinks he found a meteor. This is not a hypothetical. He’s gotten analytical data and shown it to me. Fresh off a big project like this about space materials and geochemistry, what advice would you give to him? What should he do with his maybe space rock?
Fionna: I guess what does he want to do with it? Is he just interested in if it is a meteor?
Craig: I mean, at this point, he mostly wants to prove that he found a space rock.
Fionna: Yeah. I think that you have to look at the isotopic ratios of various metals because some of them are indicative of extraterrestrial sources, and that would be the first step, which obviously you need the right instrumentation to look at isotopic ratios. And then he could give it to somebody, like a museum or something if he wanted to. I will say meteor samples are incredibly important for people who are doing extraterrestrial geochemistry because they are an Earth-based analog for these pieces of material that are off the planet. And so when we’re trying to understand asteroids or whatever, looking at meteors can actually give us a baseline of what we might expect to see from a body in space without actually having to go to that body in space, which is really valuable if you’re doing spectroscopic analysis of things that you’re not going to end up landing on.
Craig: Yeah, it makes sense. I know a lot of analytical chemistry is fingerprint matching, so having a fingerprint that we know is at least not from here. And that’s the end of my question list. Is there anything else that you wanted to talk about, about these articles that you worked on, that we haven’t touched on yet?
Fionna: I’m excited for sample return missions. That’s all. It’s hard to wrap your head around sample return missions because you have a sample that’s from outside of Earth, and as soon as you bring it to Earth, literally everything is a contaminant, right? So I’m really excited about a possible future story about how researchers design labs so that they can analyze these samples in a way that doesn’t immediately contaminate them, because literally everything is a contaminant when you have an extraterrestrial sample in your lab.
Craig: Well, Fionna and Bri, thank you for diving deep on this with us.
Bri: Thanks for having us, Craig. This was a really fun conversation.
Fionna: Yeah, thanks so much. It was great.
Bri: Read the space package.
Craig: Check it out. Listeners can find me on social media as @craigofwaffles most places. How can listeners get in touch with you?
Bri: I’m @BriBarbu on BlueSky and Brianna Barbu on LinkedIn.
Fionna: And I am FMorningstar on BlueSky, and you can email me at our ACS emails, always.
Craig: You can find Bri and Fionna’s stories about space sustainability and geochemistry of our solar system on C&EN’s website. We’ve put links in the show notes along with the episode credits. If you want more on space chemistry, let us know because the magazine space package has additional components by other reporters that we could explore here in a future episode. Overall, we’d love to know what you think of C&ENUncovered. You can share your feedback with us by emailing [email protected]. This has been C&ENUncovered, a series from C&EN’s Stereo Chemistry. Chemical & Engineering News is an independent news outlet published by the American Chemical Society. Thanks for listening.
