Planetary Radio • Jan 24, 2024

Blazing a trail to the Moon

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Bethany Ehlmann

President, The Planetary Society; Professor of Planetary Science, California Institute of Technology; Director, Keck Institute for Space Studies at Caltech

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Casey Dreier

Chief of Space Policy for The Planetary Society

Jack kiraly portrait 2023

Jack Kiraly

Director of Government Relations for The Planetary Society

Headshot 2020

Kate Howells

Public Education Specialist for The Planetary Society

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Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

Sarah al ahmed headshot

Sarah Al-Ahmed

Planetary Radio Host and Producer for The Planetary Society

We're celebrating lunar missions and the space advocacy that helps make them happen this week on Planetary Radio. Casey Dreier and Jack Kiraly, chief of space policy and director of government relations at The Planetary Society, update you on our next Day of Action in Washington, D.C. Kate Howells, our public education specialist, shares the triumph and challenges of the Japanese space agency's SLIM lunar lander, as Japan becomes the fifth nation to make a successful soft landing on the Moon. We begin our coverage of the upcoming 2024 total solar eclipse in Mexico, the United States, and Canada on April 8th with Bethany Ehlmann, the president of our board of directors and the principal investigator of NASA's upcoming Lunar Trailblazer mission. She joins us for a mission update and a look at how eclipses affect spacecraft near the Earth and Moon. We'll top off this lunar celebration with Bruce Betts, our Chief Scientist and everyone's favorite master of random space facts, as he shares some history about an iconic Apollo image.

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This is how we work for space in Washington D.C. Participants share their experiences from the 2023 Day of Action.

Planetary Society members at the 2023 Day of Action
Planetary Society members at the 2023 Day of Action Image: The Planetary Society
SLIM deploying the Lunar Excursion Vehicle
SLIM deploying the Lunar Excursion Vehicle An artist's impression of Japan's SLIM spacecraft deploying its Lunar Excursion Vehicle 1.Image: JAXA
Lunar Trailblazer
Lunar Trailblazer Render of the Lunar Trailblazer orbiter at the Moon.Image: Lockheed Martin


Sarah Al-Ahmed: We are diving into our Day of Action, JAXA's SLIM landing, and the ways that eclipses impact solar panels on spacecraft this week on Planetary Radio. I'm Sarah Al-Ahmed of The Planetary Society with more of the human adventure across our solar system and beyond. It's been another jam-packed week of space exploration brought to you by the scientists, engineers, and space advocates that'll make it happen. Up first, we've got Casey Dreier and Jack Kiraly, our very own space policy dynamos. Registration for The Planetary Society's Day of Action is now open. They'll share a big upcoming opportunity for listeners in the United States who want to spread their love of space to the halls of Congress. Then Kate Howells, our public education specialist, joins us to share the triumphs and challenges of the Japanese space agency's SLIM lunar lander. Please join me in welcoming Japan as the fifth nation of Earth to make a successful touchdown on the surface of the Moon. SLIM's Landing was a victory, but there are some troubles powering the solar panels. Kate will get into the details. And speaking of powering spacecraft, have you ever wondered what happens when a solar-powered lunar orbiter passes into darkness? We're kicking off our countdown to the total solar eclipse of 2024 with Bethany Ehlmann, the president of our board of directors and principal investigator of NASA's upcoming Lunar Trailblazer mission. She'll give us an update and discuss the planning that their team had to do to make sure the spacecraft can survive an eclipsed Sun. We'll top off this lunar celebration with Bruce Betts, our chief scientist and everyone's favorite master of random space facts. If you love Planetary Radio and want to stay informed about the latest space discoveries, make sure you hit that subscribe button on your favorite podcasting platform. By subscribing, you'll never miss an episode filled with new and awe-inspiring ways to know the cosmos and our place within it. Every spacecraft begins as a dream, from the ones that explore our solar system to the orbiting observatories that stare into the depths of cosmic time. Like all dreams that better humanity, they require hope, hard work, and advocacy to become a reality. That's why each year, The Planetary Society's members in the United States and around the world team up for our biggest advocacy event, our Day of Action. Casey Dreier, our chief of space policy and Jack Kiraly, director of government relations at The Planetary Society are here to tell us about this year's in-person event in Washington, D.C. Hi Casey and Jack. Thanks for joining me

Casey Dreier: Anytime.

Jack Kiraly: Hey, Sarah.

Sarah Al-Ahmed: It's always great to see you again. We're coming up on our 2024 Day of Action and this is going to be my first time attending in person and also Casey your first time returning in person since the COVID era, so this is exciting.

Casey Dreier: Isn't it? Also, my first time as being a parent running the Day of Action, which I don't know if it's necessarily germane to it, but feels important nonetheless.

Sarah Al-Ahmed: Human life is so complicated and I bet that puts an interesting new spin on literally everything for you including space advocacy.

Casey Dreier: Well, that and the long-term outlook of things like do I want my daughter to grow up in a world where we have done Mars Sample Return or found life on Europa or Enceladus or sent a mission to Uranus or beyond to one of those interstellar destinations? Yes, the answer is yes to all of those, and I wanted those before, but now I really want it for her because obviously that tight connection.

Sarah Al-Ahmed: That makes me so happy to hear. So I'm sure there are some people who have literally never heard of our Day of Action before. They don't even know what this is. Jack, can you us a rundown of what this event is and when it's going to be taking place this year?

Jack Kiraly: So the Day of Action is our premier advocacy event of the year. This is the thing that I'm telling you congressional staff are looking forward to because it involves people from all over the country coming to D.C. to advocate for space science and exploration, and it is the largest of these events. We are the leading organization that advocates for space and this is the event that every year people are looking forward to because our enthusiasm shows through, our knowledge of the issues shows through, and it's really that opportunity to affect real change when it comes to US space policy. So the Day of Action, if you want to make an impact, this is the event that you come to and this year we're doing it on April 29th, which is a Monday. It is the Monday where both the House and the Senate are in session, at a time when we are going to be starting to talk about FY25 funding priorities as we go into the summer months leading up to that October 1st deadline.

Sarah Al-Ahmed: And I believe even though this event is actually on the 29th, I think that people have to register by a certain date. Is that correct?

Casey Dreier: You have to register by mid-April to get a slot, and we do ask that you register because what we do, the key is that make this easy for anybody, whether you've done this before or this is your first time, we book your meetings for you. So you show up to Washington, D.C. We book all of your meetings with your representatives and you're in teams with other people and you'll meet their representatives. You have opportunities to do drop-ins with fresh representatives who maybe don't know about space very much. And then we train you the day before on April 28th. So we ask that people come to D.C. on Sunday the 28th. We have a full day of meetings on the 29th where we advocate for space, and it's just a fantastic event because you're doing it together with us. We will be there. As you said, Sarah, I'm really excited to have you here this year, but you also get to meet your fellow members of The Planetary Society and that we have seen over the years doing this has been one of the most rewarding and valuable aspects of this because you're meeting other space fans and passionate space advocates who are committing themselves. I mean, this is no easy ask that we're making of our members to fly all the way out to Washington, D.C. or drive or take time off of work and really put themselves out there. It's always, if nothing else, truly inspiring for me and Jack to see our members step up like this. And as Jack pointed out, a really great time for the members and their staff themselves in Congress that they see people so passionate about something so, in a sense, pure and optimistic, which is sorely needed right now for everybody and a great way to engage in our democracy.

Sarah Al-Ahmed: I'm really looking forward to April for this reason and because it's right after the total solar eclipse on April 8th. So I think that these two things together are really going to create just a month-long space party. Of course. Here at The Planetary Society, it's always a space party, but I think that this is going to be a really great moment to get people all across the United States and also in Mexico and Canada, really excited about space.

Jack Kiraly: Well, I will say that having the total solar eclipse scheduled for two weeks before the Day of Action, whoever did that scheduling, credit to you, because I feel like enthusiasm on Capitol Hill is going to be really high and people are going to be really excited about space, about this opportunity to explore the cosmos and understand and know our place within it. And this opportunity really allows advocates, members of The Planetary Society, members of the public to be that voice for the future of space science and exploration. And so, I think it's going to be a great moment where we're all going to come together and rally around these exciting missions that are part of our 2024 priorities.

Sarah Al-Ahmed: So what are our 2024 priorities? Because I feel like there's so much going on right now, so many shifting timelines for different missions and just so much at stake.

Casey Dreier: We go through a process every calendar year where Jack and I sit down, we try to map out what our big areas of focus are going to be, and that's a function, and that can change over time because the budgets will come out. We'll see different political things go up or down. Budgets can go up or down, and we try to be responsive to that, but ultimately, we have these core goals and interests at The Planetary Society. We want to explore worlds, we want to find life, and of course we want to defend the Earth from asteroids and those drive our specific areas of interest. And for the calendar year 2024, we are really going to be focused on, well, one, planetary exploration, NASA's robotic science missions, specifically the ones that are really struggling. Those need the help. We love all of them, right, Jack?

Jack Kiraly: We sure do. We love all of them.

Casey Dreier: We're big fans of everyone, but some of them just need more attention and some TLC than others in terms of advocacy because they are struggling. Next year or this upcoming year, obviously Mars Sample Return is going through a huge, very important decision point from NASA from Congress. We don't know the outcome of that yet, but we do know that the society supports the priorities of the scientific community, that we support the decadal survey process, which has identified Mars Sample Return as the top priority flagship robotic mission for the next year. And we know that we as an organization have talked about returning samples from Mars for decades now. This is an incredible mission. That's going to need a lot of effort and support. We're also really worried about other missions like VERITAS that we talked a lot about last year that was functionally cut. We're worried about missions like Dragonfly to Titan. We really want to see that happen. There's a lot of challenging problems facing, and it's not even necessarily the problems of engineering or management of a lot of these other missions. The budget is shrinking. We really, really, really need to push back on that. The pie is getting smaller and that makes it a lot harder to do ambitious, exciting, exploratory missions like the ones I just talked about. So pushing back on that's a big one. We want to engage and promote policy that supports the search for life where that's a really big one. We're going to be presenting a big engagement effort at the AbSciCon, the big astrobiology science conference later this year to help brainstorm the ideas of what a national policy for Search for Life could look like. And then of course, we're going to keep supporting key missions in planetary defense like NEO Surveyor, which finally got the money it needed last year, but it is waiting for Congress to pass its budget this year so it can ramp up and actually hit that 2028 launch date. So there's a lot. Let's say this has been one of the most interesting times in a while in terms of NASA budgeting, NASA policy, and politics because we have so much on the table, but we need the resources to do it. And those resources I think have become much less certain than they were even a year ago.

Jack Kiraly: And it's almost all the more reason why space advocates need to stand up and unite behind this vision. It's because this is the first year in I think forever that we're going into a new budget cycle already knowing that there's a cap in place and that the federal government budget is not going to be growing quite as much between fiscal year '24 and '25 as it has been, and that means less money to go around, that means less money for NASA, and we need to make sure that our priorities, the priorities of the space science community, are well-represented, and that's how you, the listener, the advocate can be a part of making that decision is talking to your legislators and talking to their staff. If this stuff sounds complicated, I mean it is, right? But you don't need to be an expert in planetary science or be an expert in aerospace engineering to make an impact. You are a constituent and you have three members of Congress, your House representative and your two senators who are there to serve you and being a part of the Day of Action, being a part of our advocacy efforts is how you directly influence how they think about this issue. Because the fact of the matter is NASA is less than half a percentage point of the federal budget. There are so many other things that are going to take up the oxygen in the room, not just within space, but within the greater context of the federal budget. And so, making sure that you show up and you make your voice heard is going to make a world of difference. It'll make worlds of difference in the exploration of our solar system and beyond. So if you are on the fence, this is that opportunity. We will do that all-inclusive training. We will give you the talking points. You just have to show up and bring your passion and enthusiasm for this topic and like I said, will make worlds of difference.

Casey Dreier: Yeah, I just want to add to that because this is a really important year. It's going to be a tough year. It's also a presidential election year, which means just everything else becomes more complicated, politically speaking, in terms of Congress and the decisions they'll be making. I mean, it's not just an election year, right? I mean it's a presidential election, but then all of the House is up for reelection and a third of the Senate. So there's a lot of issues. There's a lot of potential change next year. But as Jack said, we do know one thing, which is the pot of money that we have to spend this year is smaller. That is the first time NASA will have lost money, will have budget have shrunk since 2014, so we're looking at the first time in a decade that this has happened while NASA's been building up all these ambitious missions, including of course sending people back to the Moon, which was recently delayed. So that's not going to get cheaper.

Sarah Al-Ahmed: I did want to ask you about that actually, because I'm assuming that delaying the Artemis program is going to have some kind of knock-on effects for all of the other planetary science missions. Are we concerned about that?

Casey Dreier: Yes, but also it wasn't a surprise. There's a reason it's not ... Going to the Moon, as we're seeing, is very difficult. There's a reason why no other nation has even attempted it with humans since the Apollo era. That should say something, right? This isn't something people take shots at all the time. It's going to be difficult and it's a completely new way of doing it. It's going to take longer than you think. It always does. Now the question is NASA is using this novel contracting method that has fixed price commitments from the government with a lot of commercial companies taking on a lot of that risk like SpaceX and Blue Origin for the landers, that can help mitigate the cost overruns at certain aspects of Artemis. But at a certain point, there may be a transition era or a cost limit that those companies cannot bear if they haven't figured it out yet. We just don't know. This is all, I say this over, this is a huge experiment we're running. Never ... Ahistorical, right? There's no historical precedent for this, and we just don't know. So, at the moment, what we have seen from what Congress has done this year is that of the original budget proposed by the Biden White House. They asked for more money for everything, but what Congress has been willing to do only has been to give more money to Artemis, and in order to pay for that under a flat budget, it has taken it from NASA's science missions functionally, that science has gone down by about the amount that Artemis has gone up, and that will probably continue. That has a historical precedent unfortunately, and that's what we need to be really careful about. But at the same time, it wasn't because Artemis blew its budget. They had asked for more money for everything, and it just shows you the political coalition for Artemis is very deep and very strong, which is one of its strengths in a lot of ways in order to endure this. And so, the point is, as these pies shrink, we need to make sure we preserve a slice for NASA and slice for science. And unless we demonstrate that there's interest in this, and this is to go back to what Jack was saying, and I think this is a really important point. It can sound sometimes like we're being almost naive in how we present this, that, "Oh, you just go and Mr. Smith your way to Washington and say that you want some money for Mars, and your member of Congress will say, 'Great.'" The process of democracy, we all give ourselves a pat in the back. It's easy to be cynical about politics right now, particularly in the United States, but this aspect of it, space itself, is still the least cynical, the most classically understood aspect of discretional spending and representative democracy where if they see people who are interested in it, it raises the awareness. There's no preexisting strong partisan position to take on it. You actually do have an outsized level of influence. It doesn't guarantee that we'll always get what we want, but it is profoundly helpful to participate in this and we give options for it. If you can't travel to D.C., you can take action online. You can call your members of Congress, you can do things from home even throughout the year, but this is an area where your classic grassroots engagement with your representatives to raise awareness of these issues has been shown to work. And I think we'll continue to help, even if we're facing a lot of headwinds right now.

Sarah Al-Ahmed: We just got to go there and give them just as much hope as we do about the future. Feel like we'll just come in there like a ray of sunshine and give everyone something that we can really feel proud about because when we work together on these issues, we accomplish things that are so absolutely mind-blowing and it makes me feel very proud to be a part of this organization.

Casey Dreier: Thank you, Sarah. Yeah, it's the same. It's why I wanted to work here and at the end of the day, I mean, as Jack said, these are people too, and you're coming in to give a break from all the difficult, really intransient parts of politics to say that there's something grander we can do together, that we have done together, that we can continue to do together and by doing it actually makes us better as a society and as a species. That's a pretty good pitch really at the end of the day compared to what they're usually hearing. And if you don't make that argument, that doesn't mean anyone else will on your behalf. We do our best, but it's just Jack in D.C and me on the West Coast and we have members we depend. This is where we absolutely depend on our members to provide that breadth and depth of support for these issues. And there is a certain something to walking through the halls of Congress. You're seeing people run around and you walk into someone's office and you get to say, "We're talking about Enceladus today. We're talking about Mars today. We're talking about something really amazing," and having them engage with you. That's a very satisfying experience.

Jack Kiraly: And if you think that you'll be alone, if this is your first time doing this, if you're really on the fence and you don't know if you're going to be the only first timer there, about half of our participants every year, about half are first timers. So you are not going to be alone. You're going to be with your group. There's going to be people who have experienced this before. Casey and me are going to be there. Sarah, you'll be there, and we're going to go as a unit. We're going to go together unified with this vision for space exploration that literally brings people together Here in D.C. for the Day of Action, but also all around the country and all around the globe. People are excited about what's happening in space, and this is the thing that brings us together. It's the thing that gives us hope. It's the thing that Casey, as you said, makes us better as a species. Understanding the cosmos and what better message can you bring to your representative who maybe just got off the floor after a heated debate on some government program that you've never heard of before, for them to talk about space and really uplift their spirits and uplift their vision for what our nation and what our species is capable of doing. There's no substitute.

Casey Dreier: Yeah. Carl Sagan's cosmic perspective, right? An opportunity to give your representatives that.

Jack Kiraly: Absolutely.

Casey Dreier: Sarah, should we mention the website for this if you're interested in the Day of Action?

Jack Kiraly: I think so. Yeah.

Casey Dreier: It seems like a pertinent piece of information,, very straightforward to find. Registration is open now for 2024. We have early bird registration prices. If you register before March and you sign up, we will be in contact with you. We'll give you online training and background over the next few months, and then all the action is on at the end of April. So it's, all one word. Or you could just Google it and it will come up. But yeah, we look forward to seeing you and we hope you will come because it is really a wonderful event.

Sarah Al-Ahmed: And thank you both for helping to set this whole thing up for all of the love and attention and action that it takes from our participants. You are the two that really help make this happen and give everyone this opportunity and make it such a lovely and easy and welcoming experience. So I'm super looking forward to toasting to victory with all of you in The Capitol in April.

Jack Kiraly: Looking forward to it as well. It's going to be a great, unique experience. We're very fortunate to get to work on this together, and I look forward to seeing everybody. Yes, that includes you, the listener in D.C. in April, April 28th for the training. April 29th, Day of Action, See you there.

Sarah Al-Ahmed: If it feels like there's a lot of lunar news going around right now, you're right. The upcoming total solar eclipse in Mexico, the United States, and Canada is 75 days away as of the release of this show. Millions of people are gearing up to observe the dazzling display as the Moon passes in front of the Sun. You'll be hearing a lot more about this in the coming months as we gear up for our Eclipse-O-Rama event in Texas. USA. The international effort to send humans back to the lunar surface is also underway. India's lunar exploration is going phenomenally, and last week we learned about the launch of the first NASA commercial lunar payload services mission and the unfortunate fate of Astrobotic's lunar lander. Thankfully, we've got some happier but still complicated news this week. The Japanese space agency or JAXA's SLIM Mission touched down on the Moon just a few days ago. Here's Kate Howells, our public education specialist and Canadian space policy advisor to tell us how it went. Hey, Kate.

Kate Howells: Hey, Sarah.

Sarah Al-Ahmed: So we had you on the show back in September right after the Japanese space agency's SLIM Mission went off to the Moon. Can you give us a little refresher on what the goals of that mission were?

Kate Howells: Yeah, so this was Japan's lunar lander, their first effort to land on the Moon, and specifically they were trying to demonstrate a landing technique that was a lot more accurate than most lunar landings. Normally when you try to land something on the Moon, you have a target area that's maybe a few kilometers across. SLIM was intending to land within a target of a hundred meters, which is about 330 feet. So not only is this just generally very cool to be able to do this pinpoint landing, it's also going to be useful for future missions that have very specific science objectives that require landing in a specific area. So especially if you don't have a rover, you just have a lander. You want to make sure it lands in the right spot. So the SLIM mission proved a new technique of doing that.

Sarah Al-Ahmed: They also had these two quirky little rovers on board that they wanted to test as well, which I thought were really adorable.

Kate Howells: Yes, agreed. Tiny little rovers called LEV-1 and LEV-2 for Lunar Excursion Vehicle. The first one, LEV-1, hops around. Cute, definitely cute. The other one is spherical and sort of rolls around, almost kind of crawls by swinging back and forth. Really neat, interesting ways of getting around and something that you can do on a small scale. The spherical rover was about the size of a baseball. Both of them are really quite tiny like that, and you can't equip something that small with wheels or tread or that kind of thing. So again, just Japanese space agency doing some really innovative stuff.

Sarah Al-Ahmed: I'm just imagining a future where we deploy a bunch of little rolling rovers onto a world and let them all go do their thing. I think that'd be really cool.

Kate Howells: Absolutely.

Sarah Al-Ahmed: Yeah. Well, the mission actually launched and we were waiting for it to reach the Moon. It went into lunar orbit, but how did the landing go?

Kate Howells: So overall success. They landed on target on January 19th. This makes Japan the fifth country to ever achieve a landing on the Moon. Now, there was a slight caveat to that success, even though the overall mission goal was to make this pinpoint landing, and they achieved that. They did find that once the lander touched down, its solar panels were facing the wrong way, so it wasn't collecting sunlight to power itself. So this was a little bit of an issue. It did mean that the lander drained its batteries quite quickly and was powered down on that same day that it landed. They're still hoping that it'll get a chance to regain some power in a few days once the solar panels are pointing towards the Sun again. But still, it was able to achieve its goal and it still has the opportunity to conduct some science once it gets that little bit of power back.

Sarah Al-Ahmed: Yeah, I'd still count it as a success.

Kate Howells: Oh, yeah.

Sarah Al-Ahmed: I mean, honestly, we've seen so many different organizations, both commercial and government agencies try to land on the Moon, and it's really hard. And we even just saw a couple of weeks ago, Astrobotic's Peregrine Lander attempt to try to touch down on the Moon and have an issue that sadly prevented it from doing so. In the end, it's a really difficult thing, and I would still count this as a roaring victory.

Kate Howells: Yeah, absolutely. When the Peregrine spacecraft had its failure, a couple people reached out to me for commentary, and what I said was, "Space is hard. It's really difficult to do these things." It's not that this company made some obvious error or failed in some way. It's really hard. You have to be perfect to accomplish, especially landings on other planetary bodies. So even a slightly imperfect success like this is still really impressive. It's a really big stride forward for JAXA, the Japanese space agency, and with this new precision landing technique, this is going to be huge for every other nation, every other company that wants to land on another planetary body, you can do it much more precisely now.

Sarah Al-Ahmed: I think what's interesting about it is that in the context of the Moon, we have all this history of human beings going there, actually getting their stuff done and everyone returned. So I think there's this perception that if we could do it with crewed missions, why can't we do it now 50 years later? And the answer is, we got really lucky during the Apollo era. That could have gone way worse than it did, honestly.

Kate Howells: Yeah, I also always say if you pour unlimited money into any endeavor, you can pretty much achieve it. I mean, I know that there are limits to that, but the Apollo program was so staggeringly well-funded that, yeah, we were able to achieve things and make it look easy, whereas now, yeah, we're way behind on where people back in the '60s thought we'd be by now, but it's because the funding just has never been there in the same way that it was during the Apollo era. So yeah, pour tens of billions, hundreds of billions of dollars into NASA's budget again, and you'll have humans all over the place easily.

Sarah Al-Ahmed: Right? And hopefully a lot more missions that are actually out there landing successfully on other worlds. This stuff is really hard. So people's advocacy for this kind of thing, NASA's funding and funding for other space agencies like JAXA, ESA, ISRO, it's super important to the success of these missions.

Kate Howells: Absolutely.

Sarah Al-Ahmed: We'll be right back after this short break.

Bill Nye: Greetings. Bill Nye here. How would you like to join me for the next total solar eclipse in the Texas Hill Country this coming April at the Planetary Society's Eclipse-O-Rama. That's right. I'll fly you and a guest to Texas and you'll have VIP access to all things Eclipse-O-Rama, talks on astronomy, planetary science, captivating exhibits, star parties, and more. To enter, go to Donate $10 or more for your chance to win. You don't want to miss this because the next total solar eclipse doesn't come through here until 2045. So don't let time slip away. Enter today and good luck.

Sarah Al-Ahmed: I really like hearing, though, that there is hope for SLIM, despite the fact that it did have to power down. What do we need to happen in order for these solar panels to actually get the power that they need?

Kate Howells: So my understanding is that we just have to wait for the Moon's position relative to the Sun to shift. So as the Moon goes around the Earth, different parts of it enter lunar daytime and lunar nighttime. So once it is in position in lunar daytime to have the Sun's orientation be lined up with where the solar panels are facing, it will get a chance to charge up. They originally wanted it to land with its solar panels already facing the Sun. Facing the opposite direction currently, but eventually that will change. So hopefully at that point it'll charge up its batteries.

Sarah Al-Ahmed: And then we'll have you back on for another celebration. That would be so cool.

Kate Howells: Absolutely.

Sarah Al-Ahmed: But even with all those issues, it's still managed to accomplish a great amount of science and meet all of its goals. Well, meet most of its goals.

Kate Howells: Yeah, absolutely. I think for a mission like this, the main objective was this landing technique. Once they landed on the Moon, yes, of course they were going to do some science. They're in an interesting part of the Moon worth studying. People can read more about it on our mission page for the SLIM Lander. But yeah, the main objective was accomplished. The science is kind of the icing on the cake.

Sarah Al-Ahmed: I'm really impressed with what JAXA is pulling off these days. I had a friend ask me recently, what are other space agencies doing? And when I started talking about what JAXA is doing on the Moon, but also at Mars, they were really impressed because they hadn't heard about it. So while I have you here, I wanted to ask you if you could give us a little update on the timeline for JAXA's MMX mission to the moons of Mars.

Kate Howells: Yes. So MMX, the Martian Moons eXploration mission was originally going to launch later this year. It's now been postponed to launching in 2026. So this is going to go study the moons of Mars, Deimos and Phobos and return samples from Phobos to Earth. Really, really cool, very ambitious mission. Now it's looking like if it launches in 2026, it'll be bringing Phobos samples back to Earth in 2031. And this delay doesn't have to do with an issue with the spacecraft. It's actually to do with the rocket that's going to be launching it. So of course, if you put years and years of work and tons and tons of money into building a very futuristic, advanced innovative spacecraft, you don't want it to blow up because of the rocket. So it's worth making sure everything's working properly before launching. So JAXA is doing that. So we'll still see this really cool mission launch in just a couple of years.

Sarah Al-Ahmed: We all kind of have a personal stake in this mission because one of the bits of technology on board that we gave grant funding to is something called PlanetVac, which I know people have heard Bruce Betts talk about in What's Up? because he loves this thing, but that's one of the technologies that's going along with this mission, so we're all really looking forward to it.

Kate Howells: Yeah, PlanetVac is super cool. It's a sample collection mechanism that goes on the leg of the lander and it blows a puff of air out, and as that puff of air goes out, it disrupts some of the material on the surface and then it catches that. So, instead of just sucking something up, it blows and then catches what gets blown away. Really cool, and especially very cool, yes, for all of The Planetary Society members who had a direct role in making this technology happen.

Sarah Al-Ahmed: I'll have to remember to link our cute little commercial for PlanetVac on this page of Planetary Radio because it's so funny and so infomercial-like. It's wonderful.

Kate Howells: Yeah, it's a relic of an era of Planetary Society video making where we had, it was at the Wild, Wild West. We just did all kinds of kooky stuff and I'm really very into it.

Sarah Al-Ahmed: Loved it. Well, thanks for joining me Kate and for giving us an update, and hopefully, fingers crossed, SLIM will come back to life and we'll get a happy update from you later.

Kate Howells: Yeah, we'll be keeping an eye on it and everybody can be sure to hear updates if they listen to Planetary Radio, but also if they subscribe to the downlink, our weekly newsletter where we talk about stuff like this.

Sarah Al-Ahmed: Thanks, Kate.

Kate Howells: Thanks, Sarah.

Sarah Al-Ahmed: We're rooting for you, SLIM. May the Sun shine upon your solar panels. It's always so sad when a perfectly good spacecraft goes silent because it can't get sunlight. It's happened to so many of them, but if our next guest has anything to say about it, it won't be happening to her team's lunar orbiter. On our planet, we experience solar and lunar eclipses when the Earth, Moon, and Sun align just right. When the Earth passes between the Sun and the Moon, you get a lunar eclipse. The Moon's sunlight is blocked by our planet and sunsets from around the world cast their red hue onto our neighboring world. On the other hand, when the Moon passes between the Earth and our star, we get solar eclipses. These cut a path of darkness that humans chase as the Moon's shadow travels across the face of our planet. Most people think of these events as fun oddities, moments to gather and experience space, but for those who run solar-powered spacecraft in and around the Earth and Moon, these alignments of celestial bodies provide unique challenges. How do missions plan for the moments when things go dark? Our next guest is planetary scientist Dr. Bethany Ehlmann. She's a professor and director of the Keck Institute of Space Studies at the California Institute of Technology. She's also the president of The Planetary Society's board of directors. Her expertise spans a broad range of areas including mineralogy and chemistry of planetary surfaces, remote sensing, and astrobiology. She's played a key role in several NASA missions and is currently the principal investigator of NASA's upcoming Lunar Trailblazer mission. Hey, Bethany.

Bethany Ehlmann: Hi, Sarah.

Sarah Al-Ahmed: So we've got this major total solar eclipse coming up on April 8th. I'm really excited to go see this. Are you going to be with us in Texas for the Eclipse-O-Rama event?

Bethany Ehlmann: I am looking forward to being with The Planetary Society in Texas, absolutely.

Sarah Al-Ahmed: And this is going to be your first total solar eclipse, right?

Bethany Ehlmann: It is. That's one of the reasons I am so excited and I really hope the weather cooperates and we have a great shot at viewing because I have never been to a total solar eclipse before. Space geek though I am, this is one of the things I've never experienced.

Sarah Al-Ahmed: I mean, it's something that you have to be in the right place at the right time in order to experience, and I've only seen one and I tell you, it blew my mind so much and I've been dreaming of this day to go back and see it not just with my friends, but with other people. I think experiencing it with The Planetary Society is going to be a whole different thing.

Bethany Ehlmann: I'm looking forward to it. Basically a hundred percent of the people that I know who have seen a total solar eclipse have told me that it's just outstanding and sort of surreal and it evokes this feelings of wonder and awe. And so, I'm eager to experience for myself. Well, let us hope that the weather gods of Texas cooperate that day.

Sarah Al-Ahmed: Fingers crossed. I know we selected the position specifically because the weather has some good history there, but you never know when a stray cloud is going to come rain on your parade.

Bethany Ehlmann: Absolutely. But if not, I mean, the consolation prize is being with many, many space enthusiasts and I'm sure it will be an outstanding weekend of sharing our love of space, and I look forward to meeting folks there.

Sarah Al-Ahmed: Well, the reason that any of these things happen is because of our beloved moon and its position on our sky. And you are the principal investigator for NASA's Lunar Trailblazer mission. Could you tell us a little bit about the mission?

Bethany Ehlmann: Lunar Trailblazer is a NASA small satellite mission that is going to orbit the Moon and our science goal is to map the form, abundance, and distribution of water and to understand the lunar water cycle. So what does that mean? That means Lunar Trailblazer will help answer the question, is there ice on the surface in the permanently shadowed regions at the Moon, sitting there at the surface ready for us to investigate it? Why is there water at all on some of the sunlit parts of the Moon where the temperature gets really high? And we didn't even know until 2008 that it was there at all. And in the meantime, Lunar Trailblazer will also be providing some of the highest resolution maps of the temperature and temperature change on the lunar surface to get at the thermophysical properties and also the mineralogy of the Moon. What are the rocks made of? How does that change? How does the degree of space weathering of soil change? So at the same time that we're mapping water, we're actually going to get the highest resolution composition and thermophysical properties maps to help guide future landers.

Sarah Al-Ahmed: Which is so important at this moment in time when we're about to try to send humans back to the Moon. We've had several attempts at lunar missions in the last couple of weeks that have had some real challenges trying to land on the Moon. So the more we know about what it's made of and potentially where all the water is, so we could use that as a power source for some of these missions as well.

Bethany Ehlmann: Yeah, I mean, all of these are great reasons to explore. I am very interested in the science of the water as well, because that is the record of either water that came from the Moon's interior and degassed through volcanism, or it's the record of water that was delivered into the Earth-Moon system by comets and asteroids. And we know that our own Earth's water came from space, but we don't know exactly when or with what kind of distribution and what that meant for how our planet got started. So it may be that some of the repositories of this information are at the Moon's poles. So the scientists in me wants to go get at the ice in the poles in addition to the resource benefits that such ice could bring for future exploration, I think both are important and that the first step is knowing where to go, where is the ice at very high spatial resolution?

Sarah Al-Ahmed: It's funny because for the longest time I learned that the Earth got all of its water from comets. Over time, we learned that a lot of that could have been from asteroids, and then thinking about the fact that the Moon was created in a collision with the Earth and all of the strange interconnection between our two worlds, knowing more about that water could be very, very helpful. Just a few months ago, I was speaking with someone about a full granitic batholith that they found on the far side of the Moon, and granite, as we know on Earth, usually takes water to form. So it's very interesting to me that there's so much that we don't know about the Moon and its composition and the water content considering it's right next to us.

Bethany Ehlmann: Yeah, we've had the same neighbor for nearly four-and-a-half billion years, same neighbor, and we still don't know everything about them. We haven't had all the conversations yet. There's still a lot more to learn, and the Moon is really our closest planetary body for just continuing to learn more about how planets work. We have one example, Earth, and we're able to make some extrapolations, but as you just said, from the discovery of this big mound of what appears to be a granite rock on Earth that forms by plates subducting that released water, then partially melting the crust and that forms granite. We don't think there are subducting plates on the Moon, so there must be some other way of forming the structure if it's granite. And so, I look forward to the compositional data, for example, that Lunar Trailblazer will be providing that will allow us to narrow down even further the composition of some of these silica-rich features that we don't fully understand. The volcanologists of the world don't fully understand why they're there, how they got there, but it's telling us something about how planets work.

Sarah Al-Ahmed: The Moon is very interesting case because clearly it was very volcanically active at some point. It's covered in these kind of lava plains essentially on one side. The fact that one side is so different from the other is very interesting. Could Lunar Trailblazer tell us anything about why there's such a big difference between the near side and the far side of the Moon?

Bethany Ehlmann: Yeah, I mean, there have been a lot of studies about the cooling of the crust of the Moon, the effects of the tides on the Earth during the lunar magma ocean phase. So there are a number of hypotheses out there for the near side and far side differences. And one of the things that Lunar Trailblazer will be doing is providing some of the best maps of what the composition of some of these volcanic units are, and that will just feed into the overall story about how the Moon's crust evolved and how the rocks that we're seeing on the surface today came to be.

Sarah Al-Ahmed: I wonder if there's some interesting mysteries we don't even know are going to be there until we start looking at that composition. That's going to be really interesting.

Bethany Ehlmann: Yeah, I mean, one of the most exciting things for me as a planetary scientist is just I love new data because we're at a stage where we're still learning, we're still discovering. So every time that there's a new image, a new spectrum, a new signature of some type from one of our instruments, we're still learning what's in our solar system and how it all works. And so, I have no doubt that there are discoveries that you and I will not be able to guess about during our conversation today,

Sarah Al-Ahmed: We've seen a lot of lunar missions in the past few weeks encounter some serious challenges while trying to land, but something that it can be a challenge for Lunar Trailblazer that these other things probably won't have to deal with is the fact that you actually are impacted by the Moon eclipsing the Sun as you're going around the Moon with this mission, how is that going to impact your power source and what do you have to do to plan around that?

Bethany Ehlmann: One of the most interesting things as principal investigator has been working on the science engineering interface of Lunar Trailblazer to make sure it's designed to be able to achieve our science objectives at the Moon over our two-year primary mission lifetime. Hopefully we can last longer for an extended mission, but part of designing a space mission, you figure out, well, what is the most stressing case? Where is the system being driven to its limit? It might be a limit about data budget, it might be a thermal limit, might be a power limit. And in Lunar Trailblazer's case, among the most stressing situations that our spacecraft encounters are eclipses, both lunar and solar. The solar eclipse is where the Sun is blocked off of our spacecraft being the most stressing. Why is that? Well, we are a solar-powered spacecraft. In order to stay operational, to keep our computers turned on, to stay in communication with Earth, to collect science data, we need photons. And when you're in a total solar eclipse, which our mission experiences periodically even in space not getting those photons, and so there's only a certain amount of time that the spacecraft can survive and maintain a battery state of charge above the recommendation, people know it's not actually good to drain most batteries all the way. Same is true of spacecraft batteries. So you want to maintain a minimum state of charge, the min SOC on a spacecraft. And in Lunar Trailblazers case over our entire primary mission, the most stressful cases occur with lunar eclipses. So that is, in fact, what we have to design our power system to. I believe the number we ended up using was to maintain a 40% state of charge on our batteries for the current worst eclipse that we will encounter in our primary mission. But we know out ahead, I forget the exact date, but I think it's out in 2027 past when we think our primary mission where there's a deeper one, and ideally we want to be able to survive that one, too. And so, we actually have to design for those cold, dark cases where for actually multiple hours, the alignment is such that in space, there's a case where it's on the order of hours, a couple of hours that we are not receiving sunlight on our solar panels just simply given the geometry of the situation. And so, we have to be able to turn on our heaters to keep things warm, but then have enough batteries to be able to survive the eclipse. And actually in the course of our design, that led to us adding more batteries onto our system, that was the stressing case that led us to add those batteries was the eclipse.

Sarah Al-Ahmed: And that's a tricky thing to plan around because now you're upping the mass on your spacecraft that changes literally everything about your planning. So it's really interesting. They have to think that far out about that. And I'm really glad that people consider these edge cases because you would never want an eclipse to be the thing that killed your spacecraft.

Bethany Ehlmann: Yeah, that's right. I mean, this is why one has an engineer who's focused on mission design to think it through these cases and scenarios so that the engineering team knows what to plan to. So in this case, it entailed running out a number of trajectories for what happens to a spacecraft in lunar orbit from the period from 2023 out through 2029, we modeled those cases for being in lunar orbit.

Sarah Al-Ahmed: People don't understand just what complexity goes into this. You really got to think about every little thing, otherwise things could go horribly wrong that you didn't anticipate but that-

Bethany Ehlmann: Yeah, and there's a number of things that are happening at the Moon, and one of them is that we're trying new innovative ways to do space missions. Lunar Trailblazer is another member of this family of low cost but higher risk missions. And it's a challenge to make the smart decisions, but make smart decisions against a limited budget. So you can't do absolutely everything that you might want to do to test, so you try to focus on more the most important things. But these space missions ultimately come down to the details of the engineering being right. Do your spacecraft connectors of every single subsystem stay mated during the violence of the launch environment or do some of them break loose? There's all these things that one can engineer around, but it all has to work right in space.

Sarah Al-Ahmed: One of my favorite things is the chambers where they take the spacecraft and just shake them real hard to see what happens.

Bethany Ehlmann: The vibration testing, yes.

Sarah Al-Ahmed: Have you gotten to be there to see that?

Bethany Ehlmann: I have. I got to see it just yesterday, in fact, because Lunar Trailblazer's in the middle of its vibration testing, and it just so happens that we're talking to each other on day two of vibration testing. I was out at Lockheed Martin yesterday for day one, and I got to see the spacecraft and be there for one of the vibrations of our X-axis. So we're going through that testing right now.

Sarah Al-Ahmed: That's amazing. And what a coincidence, too.

Bethany Ehlmann: Yeah, you build this beautiful spacecraft and then you try to shake it and break it.

Sarah Al-Ahmed: It sounds like a personal nightmare, but if it survives, that's even better.

Bethany Ehlmann: If it survives, you're judged to be good to go for launch. So it's a test. And that's part of just ensuring the system is robust and is going to function as expected in space.

Sarah Al-Ahmed: What's the current expected launch date?

Bethany Ehlmann: Lunar Trailblazer is a rideshare. So we launch when the primary mission that we are riding along with launches. At this point, we're riding along with Intuitive Machines number two, and that is planned for later in the year 2024. It's an exciting time in space generally. I say it's one of the most exciting times to be a planetary scientist. I mean, when we worry about when our mission's going to launch, and part of the reason we're not sure when it might launch is because of launchpad congestion at Cape Canaveral because there are too many launches, you know it's an interesting time in your field.

Sarah Al-Ahmed: That is such an interesting challenge to have, and we're having to limit those launch times so much more because of the increasing number of satellites. It gets more and more complicated all the time, but we'll still have a wonderful time watching the launch, and I know that all The Planetary Society members are going to be in our member community trying to watch that launch and cheering you on. So that'll be a lot of fun.

Bethany Ehlmann: I appreciate the good wishes. And as the launch date approaches, I'm sure we'll have some events to share the excitement with our members. So stay tuned and look for that later in the year in 2024.

Sarah Al-Ahmed: Absolutely. Well, thanks, Bethany. Have a beautiful launch up in the coming future, and also I can't wait to see you in Texas for that eclipse.

Bethany Ehlmann: Absolutely. I expect that we'll be talking a little bit more about Lunar Trailblazer before the launch, and so, I think we will next see each other at the eclipse. Till then.

Sarah Al-Ahmed: Until then. We'll be hearing from Bethany Ehlmann again soon in the lead up to the Lunar Trailblazer's launch later this year. And if you happen to live near our headquarters in Pasadena, California, Bethany is giving a presentation on the mission at Caltech on the evening of Wednesday, January 31st. It's going to be recorded, so it'll be available for everyone to view online after the event, but for anyone who wants to register, I'll put a link on the website for this episode of Planetary Radio. Now let's see what Bruce Betts, the chief scientist of The Planetary Society is up to in What's Up? Hey, Bruce.

Bruce Betts: Hey, Sarah.

Sarah Al-Ahmed: We had so many big news stories in the last two weeks about the Moon, but I do think it is a big thing that we should keep shouting out from the rooftops. Japan just became the fifth nation to successfully make a soft landing on the Moon. That's five different nations of Earth that have successfully landed on the Moon without crashing. I feel like this is a moment.

Bruce Betts: It is a moment. Some of them crashed before they did, but yes, congratulations to the team. That was a big accomplishment. And they had some glitches, but they got down on the surface, soft landed, didn't do the hard landing crash that many spacecrafts have done.

Sarah Al-Ahmed: Yeah, here's hoping that that light actually ends up on those solar panels and SLIM just comes back to life. We'll see, but I'm sure we'll hear more about that in the future weeks. But I have hope. I think it might work.

Bruce Betts: Cool. Sarah says that I'm on board.

Sarah Al-Ahmed: Woo! We did get a question for you this week, Bruce.

Bruce Betts: Oh.

Sarah Al-Ahmed: I know. But you know this one. One of our listeners, Carl Cameron from the UK, was really excited by one of our recent episodes about the Dragonfly mission to Titan. That's the quadcopter that's going to be flying around that moon of Saturn. And they wanted to know whether or not the funding for this mission was actually fully secured or whether or not we should be worried or advocating for the mission. And since we were just talking about our upcoming Day of Action, what do you think? What's the scoop on that?

Bruce Betts: Well, I'd say, at the moment, my understanding is funding is there, but especially with the development that's that long and things that happen politically as well as with mission development, it's always a risk. And yes, we need to keep an eye on it and watch the advocacy. And obviously our colleagues, Casey Dreier and Jack Kiraly and others will be tracking that more carefully. But it's good now, but may not be in the future as with anything like that. So we need to track it. There are other things that are being worked right now that are in a bigger crisis mode, but it's still worrisome. But hey, it's a drone on Titan. How cool is that?

Sarah Al-Ahmed: It's going to be cool. I know that Jack had a lot of success last year during the Day of Action carrying around a 3D printed Mars Sample Return container, and that that really made an impression on everyone in Congress that he showed it to. So maybe I need a 3D printed tiny Dragonfly, carry that around with me and be like, "Look, you want this on Titan."

Bruce Betts: I think you should kick it up a notch and get a flying drone model of it. Of course, they probably don't want to fly that near The Capitol, but maybe just walk it around,

Sarah Al-Ahmed: It'll be great. It'll be awesome. But really, though, I mean all of these space missions, no matter how secure they appear, all of them really need our advocacy. There are some that we're going to focus on, but if you're really passionate about insert mission here, go ahead and write your representative or whatever nation that you live in. Write the people that have the power of these things and just let them know you're excited because these things don't happen in a vacuum. You know, space exploration ... Well, I guess. But space exploration happens because we want it to happen. So if you love something, tell the world about it. Otherwise no one will know.

Bruce Betts: Wow, cool tunes.

Sarah Al-Ahmed: All right. Let's do our random space fact.

Speaker 8: Random space fact.

Sarah Al-Ahmed: I don't know if you're crawling up from the depths or if you just need more coffee.

Speaker 8: Yes.

Bruce Betts: Both are true. So this one's rather specific and refers to one picture from 1969, and it just intrigued me. I was not aware of this. You have probably undoubtedly seen the picture of Buzz Aldrin standing on the Moon with Neil Armstrong and the reflection of his visor and the lunar lander and him just being astronaut on the Moon. But what's interesting, besides the fact that everything in that picture is interesting is that when they release the image, NASA released the image hours after it was taken, there was black space around him, of course seeing the black sky and then there's black space above his head. But that's not apparently how the image was framed by Neil Armstrong when he took it. It actually cropped off the very tip-top of his helmet and someone at NASA added more black space to the top to make a more photographically centered image, and that is the image that ended up being used in Life magazine, the press. And to this day, you continue to see it. And I was so confused when I was seeing two versions that I pursued this. So again, a single image, random space fact kind of specific, but I thought it intriguing.

Sarah Al-Ahmed: It is really intriguing and answers a lot of questions for me because I remember during the 50th anniversary of the Apollo 11 mission, I was trying to put together a PowerPoint and I came across this exact situation where I was going through the original images and I was like, "Where's the rest of the top of this? There's no black above this. Did they add to it? How did they even do that? It's not like they had Photoshop in 1969."

Bruce Betts: I don't know. I'm curious, and people can write in if you know more. It's the NASA History Office that actually is the source on the web that this happened. So it's a good source. You can see both versions. There's a little tiny antenna that is on the top of the helmet that you can see got cut off. If you look at what should be there versus what is there.

Sarah Al-Ahmed: In the end, we don't like to doctor space photos. We're trying to be very careful about it. But in the end, I think in that instance, I'm kind of glad they did it because that image became so iconic and if it was framed all wacky and still tried to put it on Time magazine, I don't think it would've hit the same.

Bruce Betts: I wouldn't give it so far as it was framed wacky. But yeah, he cut the tip-top of his helmet off, which I can't really blame Neil Armstrong because he was on the Moon and wearing a spacesuit.

Sarah Al-Ahmed: But it makes the case that we should teach all of our astronauts a little bit of basic photography and framing before we send them to the Moon.

Bruce Betts: I'm guessing they will. Well, when they hear this, they definitely will. You can teach them. It'll be great.

Sarah Al-Ahmed: Yeah. Down to teach that class. All right, let's take this out.

Bruce Betts: All right, everybody go up there, look up at the night sky and figure out where you would add black space in your life and your pictures. Thank you. Good night.

Sarah Al-Ahmed: We've reached the end of this week's episode of Planetary Radio, but we'll be back next week with a fun but complex question. How common are total solar eclipses in the universe? The answer may shock you. Love the show? You can get Planetary Radio T-shirts at, along with a lot of other cool spacey merchandise. Help others discover the passion, beauty, and joy of space science and exploration by leaving a review and a rating on platforms like Spotify and Apple Podcasts. Your feedback not only brightens our day, but helps other curious minds find their place in space through Planetary Radio. You can also send us your space thoughts, questions, and poetry at our email at [email protected]. Or if you're a Planetary Society member, leave a comment in the Planetary Radio space in our member community app. Planetary Radio is produced by The Planetary Society in Pasadena, California and is made possible by our members from around this beautiful planet. We'll keep advocating for space exploration until Moon missions are so common, you'll be sick of them. That's not possible. You can join us and help many more amazing space missions launched to success at Mark Hilverda and Rae Paoletta are our associate producers. Andrew Lucas is our audio editor. Josh Doyle composed our theme, which is arranged and performed by Pieter Schlosser. And until next week, ad astra.