Planetary Radio • May 03, 2023

Adventures at the 2023 Planetary Defense Conference

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Mat Kaplan

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

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Nancy Chabot

Planetary Chief Scientist at Johns Hopkins Applied Physics Lab, and Coordination Lead for DART

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Andrew Rivkin

Investigation Team Lead at Johns Hopkins Applied Physics Laboratory

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Lindley Johnson

Planetary Defense Officer for NASA

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Casey Dreier

Chief of Space Policy for The Planetary Society

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Jim Bell

Past President (2008-2020), Board of Directors of The Planetary Society; Professor, School of Earth and Space Exploration, Arizona State University; Principal Investigator, NASA Perseverance rover Mastcam-Z instruments

Nahum Melamed

Project Manager for Aerospace Corporation

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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

Additional guests include:

  • Katelyn Scherer, DART Project Manager at the Johns Hopkins Applied Physics Laboratory
  • Terik Daly, Deputy Instrument Scientist for the camera on DART, Johns Hopkins Applied Physics Laboratory
  • Leviticus Lewis, FEMA Detailee, NASA Planetary Defense Program Officer at NASA’s Planetary Defense Coordination Office
  • Halilu Ahmad Shaba, Director General of Nigeria’s National Space Research and Development Agency
  • Alissa J. Haddaji, Planetary Protection and Defense Projects, Committee on Space Research (COSPAR), now Space Law and Policy Faculty, Harvard University

Planetary Radio creator Mat Kaplan shares a look behind the scenes at the 2023 Planetary Defense Conference in Vienna, Austria. You’ll hear exclusive interviews with planetary defense specialists from around the planet as they gather to push the boundaries of asteroid and comet deflection technologies. Stick around for What’s Up with Bruce Betts, an update on the night sky, and a look forward to the upcoming Eta Aquarid meteor shower.

Asteroid Hunters screening at the 2023 Planetary Defense Conference
Asteroid Hunters screening at the 2023 Planetary Defense Conference The Planetary Society, a co-sponsor of the biennial Planetary Defense Conference, hosted a screening of the movie "Planet Hunters" at the 2023 conference in Vienna, Austria. This image shows the crowd at the event, which senior communications advisor Mat Kaplan hosted.Image: Alex Karl
UN conference room at the 2023 Planetary Defense Conference
UN conference room at the 2023 Planetary Defense Conference This image shows the crowd gathered in the UN conference room at the 2023 Planetary Defense Conference in Vienna, Austria.Image: Mat Kaplan
Chief of Space Policy Casey Dreier at PDC 2023
Chief of Space Policy Casey Dreier at PDC 2023 Planetary Society Chief of Space Policy Casey Dreier presents his paper, "How Planetary Defense Budget Grew by More Than 4000% in 15 Years," at the 2023 IAA Planetary Defense Conference in Vienna, Austria.Image: The Planetary Society
Mat Kaplan interviews Nahum Melamed at the 2023 Planetary Defense Conference
Mat Kaplan interviews Nahum Melamed at the 2023 Planetary Defense Conference Mat Kaplan interviews Nahum Melamed of the Aerospace Corporation for a Planetary Radio segment while attending the Planetary Defense Conference in 2023.Image: Alex Karl
Mat Kaplan at the Planetary Defense Conference
Mat Kaplan at the Planetary Defense Conference The Planetary Society senior communications adviser, Mat Kaplan, on a communications panel at the 2023 Planetary Defense Conference.Image: Casey Dreier

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Sarah Al-Ahmed: Join us on an adventure to the 2023 Planetary Defense Conference, 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. The Planetary Defense Conference took place in Vienna, Austria last month. Mat Kaplan, The Planetary Society's Senior Communications Advisor, will share a look behind the scenes at the conference and what it means for the future of planetary defense. Then Bruce Betts, our chief scientist, will update you on the upcoming night sky and the Eta Aquarid meteor shower. Now it's time for some space news. Unfortunately, the Japanese ispace lunar lander is presumed to have crashed. The HAKUTO-R Mission 1 lander, which was developed by the private company ispace, attempted a landing on the lunar surface on April 25th. The touchdown ended in a loss of communication from the lander. Ispace CEO Takeshi Hakamada said that the mission still yielded a lot of valuable information, and will help future lunar missions succeed. China has announced new plans for two of its space science programs. The China National Space Administration announced last week that its Tianwen-3 Mars sample return mission, which is scheduled to launch in 2030, will likely use a small helicopter like NASA's Ingenuity. The helicopter will collect samples near the accompanying lander. The agency also announced its plans to build and launch an array of telescopes in deep space to search for habitable planets orbiting other stars. And of course, the Ingenuity Mars helicopter is back at it. The experimental drone completed its 51st flight, and snapped another iconic image of its shadow from about 12 meters, or 40 feet, up. The Perseverance Rover also makes an appearance in the image in the top left in the distance, blending into the Red Rocks at the rim of Belva Crater. Speaking of awesome pictures from the Red Planet, on our April 5th show, we celebrated two years of the Emirates Mars Mission with Mohsen Al Awadhi, Director of the Space Missions Department at the UAE Space Agency. He teased the Hope Probe's upcoming images of Mars' moon, Deimos. I'm happy to announce that they were released last week, and they're gorgeous. You can check out these images and learn more about these stories in the April 28th edition of our weekly newsletter, The Downlink. Read it or subscribe to have it sent your inbox for free every Friday, at Planetary Radio's creator and longtime host, Mat Kaplan, is back. He's now The Planetary Society's Senior Communications Advisor and he's just returned from the 2023 Planetary Defense Conference. In addition to hosting a live public event, he also caught up with a handful of this year's conference attendees. Here's his report.

Mat Kaplan: This year's gathering in Vienna, Austria was my fourth Planetary Defense Conference. The PDC is the biannual gathering of planet Earth's top experts on near earth objects, the havoc and heartbreak an impact by a big one could cause, and how we are learning to avoid such a catastrophe. The four day April meeting was the biggest yet, with attendees from every continent, including Antarctica, if you count the researchers who look for media rights there. The Planetary Society is a longtime primary sponsor of the PDC. Defending our world from these threats has long been one of our core enterprises. We were joined by the International Academy of Astronautics, the European Space Agency, and NASA's Planetary Defense Coordination Office. Other supporters and sponsors include organizations ranging from the Austrian Academy of Sciences to the United Nations Office for Outer Space Affairs. In fact, the first three days of the conference were hosted by the UN at its sprawling complex next to the Danube River. It was there, on the first day of the conference that I met four members of the Johns Hopkins applied Physics Lab team behind DART, the Double Asteroid Redirection Test. It was on the 26th of September last year that DART slammed into Dimorphos, the 177 meter wide companion to much larger Didymos. The first session of the 2023 PDC was devoted to hearing some of the early and spectacular results of the mission, including the thrilling confirmation that we really did change the course of a space rock. If you've been with us a while, you'll recognize the first of the DART folks I talked with during a break.

Nancy Chabot: Nancy Chabot, DART Coordination Lead at the Johns Hopkins Applied Physics Lab.

Katelyn Scherer: Katelyn Scherer, DART Project Manager at the Johns Hopkins Applied Physics Lab.

Andy Rivkin: Andy Rivkin, Investigation Team Lead at the Johns Hopkins Applied Physics Laboratory.

Terik Daly: I'm Terik Daly. I'm the Deputy Instrument Scientist for the camera on DART, also at the Johns Hopkins Applied Physics Laboratory.

Mat Kaplan: Nancy, I'm going to start with you because as spectacular as it was looking at these images and hearing this data, these results, I kept glancing over your way. You were just beaming ear to ear during this entire first session at the PDC, and it's easy to see why.

Nancy Chabot: It is absolutely easy to see why. I mean, DART has been hugely successful, and I think one of the things that's so gratifying is to see all the different data sets coming together to give this picture about not just what DART did, but what it's going to lead to going forward, what this means for developing a technology to potentially prevent impacts from hitting the Earth.

Mat Kaplan: You have done such a good job over quite a few years now, keeping us up to date on the mission, but we do have all these other great folks for us to meet. I'm going to jump over to you, Andy, first. Not bad for a science mission, huh?

Andy Rivkin: It's not bad for any kind of mission. We really did a great job. The engineers did an amazing job of delivering us there and allowing the experiment to happen, and then of course our international investigation team has done an amazing job of interpreting the data, making the measurements, following this beautiful object, this beautiful comet we made across the sky, and letting us do this work to hopefully prevent impacts in the future.

Mat Kaplan: First human created comet. I hadn't thought of that.

Andy Rivkin: Well, yeah, some folks, some colleagues I have who work on natural comets maybe don't like to hear that so much, but I tell them, "If no one had seen it before and they found it in the sky, they would absolutely be calling it a comet." It's got most of what comets have, just we had to make it ourselves.

Mat Kaplan: One of the more spectacular images, we saw the very last presenter today representing LICIA, that wonderful little companion of DART's. We got to talk to the head of the LICIA mission at the Artemis 1. Well, the first attempt, anyway, to launch Artemis 1, because there was such a great international turnout there. I just wonder if any of you have any thoughts about, I assume the enormous amount of gratitude you must have, because you got that grandstand view of this impact?

Katelyn Scherer: LICIACube was a huge partner for Dart. Without LICIACube's contributions we would've only had, which were amazing anyways, our space-based and ground-based telescope measurements. But because of LICIACube being there during the DART impact, we were able to see this fabulous ejecta, and we're able to understand more about the structure of DART, and be able to understand a little bit more about the composition as well. And this is all amazing, which would not have happened without LICIACube.

Mat Kaplan: In this very next session, we're going to be picking up the next step out at Didymos, and that's the Hera mission. I just wonder, anybody have thoughts about what you're hoping they'll see? Yes.

Terik Daly: So I'm really excited for them to measure the mass of Dimorphos. That is the largest uncertainty we have right now in beta, and in the system, and as the person that built the shape model in large part for Dimorphos, it's great, but to actually have a direct measurement of the mass will reduce a lot of the uncertainties that we have, and move us towards that more operational planetary defense capability, once we understand beta as a value rather than this large range with tons of the uncertainty in the mass.

Mat Kaplan: I assume we're going to be seeing papers generated by DART, by LICIACube, for maybe years to come?

Andy Rivkin: Yeah, we've already had the first set of papers come out. We're probably up to six or seven or eight by now. We're making sure by team policy that they're open access, so anyone can get to them and the various journals they're published in. Looking at those amazing LICIACube images, like we said, looking at these amazing Draco images incoming, I'm also personally hoping that we see images in sci-fi movies that are inspired by, here's what an impact in space looks like. Here's what happens when you hit an asteroid with stuff. That this now sets the paradigm for the next generation of people to get inspired by space, go into the movies inspired by sci-fi.

Mat Kaplan: Nancy, where do we go from here? I mean, other than seeing this data continue to come in and papers being published.

Nancy Chabot: Well, it's exciting to be here just right now at the Planetary Defense Conference where we're sharing all of this. We've got numerous team members here, and we're sharing it with the international community. There's going to be some great discussions here about what are those next steps, what goes forward? We're excited about Hera, NEO Surveyor, finding the asteroids. We can't do anything about them if we don't know where they are. It's all going to be part of this larger strategy. And then I was part of the decadal survey as well, and so I'm very excited about what goes forward. That DART was just the start, that we're opening up this whole era of pioneering planetary defense, and taking step after step after step to make this future that we want to live in.

Mat Kaplan: Thank you, all of you, and beyond that, thank you to you proud parents and everybody else who contributed to this mission. Maybe our most dramatic step ever toward achieving one of the primary initiatives of my organization, The Planetary Society, planetary defense. Defending us from that rock out there that has our name on it. It's out there someplace, right? Thank you everybody.

Katelyn Scherer: Thank you.

Nancy Chabot: Yeah, great to talk with you.

Andy Rivkin: Thanks for having us.

Mat Kaplan: The European Space Agency's Hera mission will begin its journey in October of this year. The spacecraft will make humanity's third visit to Didymos and Dimorphos in 2026, following DART and LICIACube. So it was appropriate that the second session of the 2023 PDC was devoted to this mission, but before it began, I grabbed Lindley Johnson, NASA's Planetary Defense Officer, for a brief conversation. Lindley, we're right outside, the second session has just begun. I don't want to keep you from hearing about the Hera mission in there, but I'm so glad to catch you again. I don't know, it's probably a little too grand to call you the father of the feast, but when you think of the role that NASA and the Planetary Defense Coordination Office has played in this effort, I mean, we just heard it all in that glorious report from the DART team. This has got to be gratifying.

Lindley Johnson: Well, yes it is. You see all this culmination of a lot of hard work by folks over the last few years, but there are those of us that have been in this business for two and three decades now. When we started out, when it was still a giggle factor about this whole thing. So it's extremely gratifying that our first missions have been so successful, and they have been international missions as well. The participation on the DART mission by the Italian Space Agency was... And what we got from the LICIACube is just spectacular.

Mat Kaplan: Those LICIACube images, just... I mean, I've seen them on the page before, but watching them on the big screen here at the conference just blows me away.

Lindley Johnson: Yeah, I mean, their success with such a small project, and such a small spacecraft, as a contribution to the overall DART mission, is just great. And the relative magnitude of effort has gone in equally worthy of celebration as the entire DART mission.

Mat Kaplan: When I walked up, and she's now gone back into the conference to hear the next session, you were standing with Amy Mainzer. Is it safe to say the next big effort in space by NASA and the PDCO?

Lindley Johnson: Yes, absolutely. The NEO Surveyor mission is one that has been works for a while, as you know, and we now have it on its way for development, full scale development and launch no later than 2028. And that is going to be the next significant step, because we got to find them first. We can't do anything about them unless we find them, know what orbits they're in, predict, and that's what NEO Surveyor is going to do for us. It's not going to be the spectacular event, DART hitting an asteroid, but it is actually more important that we have this catalog of potentially hazardous objects in hand, so we know, if anything, what we need to worry about, and when we need to worry about it.

Mat Kaplan: Got to find them before we can knock them off course.

Lindley Johnson: That's absolutely right. Or knock them into a better course.

Mat Kaplan: Yes, exactly. Yeah. A better way to put it. You already said it. You have been at this for decades now, and when you look at that crowd in there, which I'm just assuming is the biggest that has ever attended a PDC, and then we have all the people participating virtually. You said that we're past the giggle factor. We really do seem to be well past that. This now seems to be well recognized by the international community as something we should learn how to deal with.

Lindley Johnson: Oh, yes. Well, the support that we've gotten from the United Nations and the Office of Space Affairs here has been great, and they got involved with us now two decades ago, quite frankly, when we started out the Action Team 14 and the NEO working group here, with the Office of Outer Space Affairs. And to see where it is now. The support, very serious topic of discussion within the United Nations and the Committee on Peaceful Uses of Outer Space. When I started things three decades ago, I mean, that was just a vision that we'd have this level of international cooperation. So it's great to see, and I'm just thinking about that, sitting down there at the opening speech by Nicholas Headman of how far we've come.

Mat Kaplan: Thank you, Lindley, for all the leadership that you've shown over these three decades, and for continuing to lead this on behalf of NASA.

Lindley Johnson: Yeah, yeah. Well, it's been extremely gratifying, the people that are involved, but to make it happen, I just kind of direct the cats where they need to go.

Mat Kaplan: All right. Well, good herding there.

Lindley Johnson: Thank you. Thank you.

Mat Kaplan: I wasn't the only Planetary Society representative at this year's PDC. I caught Casey Dreier, our Chief of Space Policy, and the host of the Space Policy edition of Planetary Radio moments after he delivered an excellent presentation. Casey, we just finished the session here at the Planetary Defense Conference that perhaps would be nearest and dearest to you, although I know you have an undying interest in everything that's being talked about here.

Casey Dreier: That's true. I have a personal interest in not getting hit by an asteroid, and I'm very happy to see a lot of other people share that.

Mat Kaplan: Certainly everybody here, and working in the forefront of avoiding that situation. I've already mentioned this a couple of times in other situations, but your presentation, which by the way was excellent, one of the best delivered, and also fascinating data, talks about this enormous increase that you've been able to document in the funding of planetary defense, at least in the US.

Casey Dreier: Yeah, I mean it helps that it used to be very, very small. It used to be in the single digit millions per year, and I pointed out in that talk, less than one third of what NASA headquarters would spend on employee travel.

Mat Kaplan: Love that.

Casey Dreier: Per year. We couldn't marshal even a third of that to spend on looking for asteroids. That has greatly increased over the years, 4000%, so from a very small number to a more modest number, about 150 million on average per year. And that enables all of the things that we're seeing. The fact that we were talking about results from an active space planetary defense mission, DART, is a consequence of that. The fact that we have these brand new ground-based survey telescopes all over the world, and of course that we're pursuing now NEO Surveyor, that is a function of the dollars we're able to put into the effort. And that's what I always point out and why I'm always obsessed with what dollars do, right? Because policy, as I point out in my talk, policy is cheap. You can write all the policy you want, words are free, but when it comes down to actual prioritization, you have to follow where the dollars go, because you can only spend those once. And now seeing it start to go into planetary defense, that tells us something fundamental has changed within the bureaucracy and within the system that is accepting the idea of planetary defense as a valid use of those limited dollars.

Mat Kaplan: So you have documented this tremendous increase in investment. What's behind it? And is it, to a degree, as we see missions like DART funded, is that helping to drive the investment?

Casey Dreier: It's certainly a snowball effect, and I think the key part for me is at the beginning, the first couple of decades of where we were not able to make the case. And as I point out, the fundamental case for investing in planetary defense is what I said at the very beginning of this interview. We don't want to be hit by an asteroid. We've known that's the case for a long time. That's always been bad. No one has ever disagreed with that, but it was unsuccessful in driving funding to the program. And so what I think actually drove the funding was something far more prosaic and practical, which was what can planetary defense do for the bureaucracy that's funding it in an immediate sense? We can think of bureaucracy having entrenched interest. NASA has an entrenched interest in human space flight, and science, and aeronautics. And the two biggest jumps early on in planetary defense funding was related to when the human space flight program briefly considered going to an asteroid as its primary destination. I don't even have to guess about this. This connection was made explicit in the funding request provided to Congress that this effort, NEO observations, will not only help us find asteroids that might kill us. Sure, yeah. It'll help us find destinations for astronauts. And I think those were the funding... Those were the primary motivation for increasing funding at those points. And then we also have with DART a workforce organizational issue with providing resources to APL and other key NASA technology investments. That it provided a platform and an opportunity to use those, in addition to doing a planetary defense effort, a planetary defense spacecraft mission. And it's this dual use, what Mike Griffin, former NASA administrator, characterized as real and acceptable reasons for investing in space flight. And the acceptable reasons tend to dominate the policy discourse even if the real reasons, like saving humanity, are pretty strong themselves.

Mat Kaplan: And APL, of course, Applied Physics Lab behind the DART mission, primarily primary backer of the DART mission and creator of it. Just talking in the few moments we have about what you've seen in the conference so far, are there particular highlights that have excited you, or made you feel more threatened?

Casey Dreier: Well, I mean, I think obviously seeing real data from DART was just truly exciting. That has never happened At a planetary defense conference before, we have a flight mission. I was very excited to see the planned missions from ESA coming our way. The fact that they're working on the Hera mission to follow up on the DART impact, but also the NEOMIR, their own in-space near Earth object detection mission, very complimentary to NEO Surveyor. We see that ESA's investing in new ground-based observation capabilities. I saw talk of investments from New Zealand, [inaudible 00:20:21], China. The fact that this global effort, this case has been made globally now. And again, going back to this original funding issue about what drove it, the fact that we're at a much more mature point now in terms of planetary defense that we've had this mission, it has entrenched itself successfully, I think, into the bureaucracy and now can more effectively continue itself and sustain itself. And the fact that NASA does it, I think also carries a certain imperator that enables other nations and other space agencies to point to NASA and say, "NASA and ESA do it. This is a legitimate opportunity and a legitimate activity that we can contribute to as well." And that was truly exciting to me, to see all the things coming down the pipeline. So I really left this conference with this idea that DART is just the beginning. This is not a one-off mission. This is the start of a new era of planetary defense for humanity.

Mat Kaplan: I wonder also if you have a sense of satisfaction in the performance and the contribution made by our own organization, The Planetary Society as you hear all of this data and all of this interest.

Casey Dreier: Well, of course. I mean obviously we're a co-sponsor of the Planetary Defense Conference and have been for many years. The Planetary Society was a supporter of planetary defense way before. It was cool. We understood that.

Mat Kaplan: That should be on a shirt.

Casey Dreier: Yeah, exactly. This is something that's been core to our organization, and really important to it and even just discussing, I was able to share with a reporter the work that our Shoemaker NEO Grant recipients do and the fact that one of them the other year discovered a one kilometer sized asteroid from Brazil, and really added to the corpus of knowledge of our threat assessment out there. And the fact that The Planetary Society, through our Shoemaker grants, are directly enabling planetary defense, and through the work that I do with our colleagues and our listeners who participate as advocates in increasing the funding, increasing the resources, that this all has a direct consequence to the long-term success of the human species, through understanding the proper level of threat. And again, I kept thinking about NEO Surveyor, the fact that NEO Surveyor now has talked about not as an if, but as a when. And we're talking about this mission as it's engaged and building, it's happening now. And Amy was up there, Amy Mainzer, who's the head scientist of that mission, showing pictures of flight hardware being built right now for NEO Surveyor. That is just a truly satisfying thing to see. And again, when I say The Planetary Society, we get nothing financial out of advocating for these things. That makes us unique in Washington DC, but I have to say, we get something soul searing and satisfactory from seeing the results of these missions we work so hard to support up there on the screen.

Mat Kaplan: And I suspect our members feel the same. Thank you, Casey. Enjoy the rest of the conference, and keep up the good work.

Casey Dreier: Oh, it's so happy to be here with you, Mat.

Mat Kaplan: The PDC is much more than space scientists and engineers. The conference also attracts social and political scientists like Casey, as well as people who help us mitigate and recover from the more common sorts of natural disasters that plague our planet. For example, there was Leviticus Lewis, who goes by LA. He is part of the US Federal Emergency Management Agency, or FEMA, and has been a regular at the conference. LA works with the White House Office of Science and Technology Policy, and Lindley Johnson's Planetary Defense Coordination Office. LA, it's been a few years, but we have talked at past Planetary Defense Conferences. Your boss, the deputy administrator, is at this one. I guess this is some kind of recognition by FEMA that this is really something you guys have to keep an eye on.

Leviticus Lewis: Yeah, that is very true. I think over the years we've been working with NASA since about 2010, formally. FEMA is all hazards, but it is a unique hazard. It's a low probability with extremely high consequence event, so that makes our list of things to be concerned about.

Mat Kaplan: We can't yet, at least we're not very good at, predicting earthquakes. We don't know how to deflect a hurricane. This, we often say at The Society, the only natural disaster that maybe can be prevented, but I don't know if that's in FEMA's area. I mean, would you be involved in the deflection effort or only, "Okay, now we have to get people out of the way."?

Leviticus Lewis: No, I think the approach that we're taking now with regard to our leadership is recognizing that this is a hazard. The science of it might be unique compared to some of the other things that we're used to, hurricanes. Right now we're also adjusting looking at what we might have to do for climate change, how that's going to affect operations in the future. So this is a different kind of disaster. The science might be different, but we have our obligation to understand the science, and learn that, if there are things we might have to do differently, we're responding to a planetary defense scenario, that we're prepared to do that.

Mat Kaplan: If the rock is big enough, this asteroid is going to be an international challenge, not just for one nation. Is FEMA involved in these efforts to-

Leviticus Lewis: We are involved in those kind of things on a regular basis anyway, but we do it through our colleagues at the State Department via US AID, so it's not going to be an unusual event for FEMA. We will lend assistance as directed by the president, and lend assistance as required, as requested through the regular State Department protocols that are already out there. FEMA is a domestic organization, but we have the, for instance, the International Search and Rescue teams that are certified in the United States. That's part of our thing, so you can imagine that if there's an asteroid impact anywhere, of any kind of significance, the United States is going to be involved, and we're going to lend a hand.

Mat Kaplan: It's good to know and good to see you folks here as well. Thanks again.

Leviticus Lewis: Thank you. Thank you very much.

Sarah Al-Ahmed: We'll be right back with the rest of Mat Kaplan's adventures at the Planetary Defense Conference after this short break.

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Mat Kaplan: One of the most encouraging developments at this year's Planetary Defense Conference was witnessing how truly international it has become. After he left the stage, I introduced myself to Halilu Ahmad Shaba, Director General of Nigeria's National Space Research and Development Agency.

Halilu Ahmad Shaba: And I'm here in this conference to discuss planetary defense, and also have ideas of where collaborations will take us to.

Mat Kaplan: We had just completed a portion of one of my favorite components of the PDC. Experts led by Paul Chodas of NASA's Center for Near Earth Object Studies came up with an extremely realistic but entirely hypothetical asteroid encounter. The simulation progressed over the course of the conference generating surprisingly real concern and anxiety among the attendees, and giving them a great path for exploration of how they would respond to a genuine threat. As we know, asteroids don't care where they fall, they can come down anywhere, and we saw the track of that asteroid in this hypothetical situation, which is being considered now. And a great deal of that track was over Africa. I didn't actually notice if it crossed over Nigeria, but certainly if it's big enough it's going to affect the entire continent as we saw. Purely hypothetical, of course. It's very good to see someone here representing that continent, which is not always as represented perhaps as it should be in a situation or a discussion like this.

Halilu Ahmad Shaba: Thank you so much. From the hypothetical scene, it crossed over Nigeria.

Mat Kaplan: Okay.

Halilu Ahmad Shaba: So yeah, I saw it. It crossed over in Nigeria, and you can imagine the size of the country, so if it's... The track, that is the belt, or the corridor, you can see where it passed through is where you have the middle belt. And the middle belt has high population, and this is one area where impact will definitely need to be protected. It passes over Abuja, which is the federal capital of the country. So virtually this kind of collaboration and this kind of information is very vital, because awareness needs to be created and the timeline given, as much as it is large, we said it is so close here, you need to inform politicians. You also need to have larger consultation and engagement with experts, so that at least you have common front when dealing with issues like this.

Mat Kaplan: Do you feel that there is a need for more cooperation? More participation by nations like yours that have space programs, but are not as active in the kinds of missions we're hearing about here today?

Halilu Ahmad Shaba: Yeah, there is a need, because you also need to develop capabilities. If you don't attend meetings like this, if you don't join, definitely there is no way you can build capabilities to deal with what is impending. So virtually it has also brought to the fore the fact that collaboration is needed, and this is where you find the necessary collaboration, by looking at what others are doing, the information that is available. So there will be that need, because some information and some capabilities are not residing within the African countries. So definitely you need to collaborate so that you get this information, and act quickly.

Mat Kaplan: Some of the discussion today has talked about a not entirely successful deflection, a partial deflection, which might let's say avoid some major population center in the Northern Hemisphere, but drop it into someplace where there are still a lot of people who are going to be terribly affected-

Halilu Ahmad Shaba: Yes.

Mat Kaplan: Somewhere else in the world. And it seems that those voices need to be heard.

Halilu Ahmad Shaba: Yeah, well for sure the voices need to be heard because definitely the one is when you deflect, you are deflecting it to the original target, or original position where it's going to, and then you are deflecting it to another place, which could be where you even have larger population, despite the fact that they are not successful. I think we need to look for other means of dealing with this, rather than the nuclear bomb that we use, and considering the fact that a lot of, it's not target, I mean it's not even accepted legally. You need waivers to do what you want to do. Definitely there is the need for us to start thinking about what can we do different from what we're doing? How can we increase our predictions, and also then increase our targeting of the meteorites. And then also since we are going to have knowledge, for example, now we have information of about 13 years, okay, if we deflect it, what is a potential outcome? There is a need for us to simulate to see the potential outcome of what we intend to do because at times when you deflect, you are deflecting it to where you have larger population, I mean, and living where you have less population. So this is essential.

Mat Kaplan: It's an essential discussion. Thank you very much, Dr. Shaba. Enjoy the conference.

Halilu Ahmad Shaba: Thank you so much.

Mat Kaplan: The Planetary Society has sponsored a public event at each of the Planetary Defense Conferences. This one brought hundreds of conference attendees and Viennese to a Cineplex in a huge shopping mall not far from the conference. I watched and was enthralled by the IMAX documentary Asteroid Hunters. See it if you can, you won't just witness a spectacularly filmed Introduction to Planetary Defense. You'll also see many planetary defense leaders, whom we've hosted here on Planetary Radio. Several of those stars joined me for a fascinating panel discussion following the screening, and one of the conference attendees who joined us in the theater was our own Jim Bell, member and past president of The Planetary Society's Board of Directors, and Professor in the School of Earth and Space Exploration at Arizona State University. Jim is also a principal investigator for the Mastcam-Z camera on the Perseverance Rover that is continuing its exploration of Jezero Crater on Mars. Jim Bell, I hope you had as much fun tonight as I did.

Jim Bell: Holy cow. It is just awesome to think about and watch a spectacular film about saving the planet.

Mat Kaplan: Yeah.

Jim Bell: Wonderful stuff.

Mat Kaplan: And you didn't just come here to see the film and join us tonight. I mean, you also made a presentation today, which because of this program we just finished, I missed.

Jim Bell: One of the things that we're doing, I work with asteroid science and missions and we're trying to put together a new kind of mission tapping into some of the many, many space agencies around the world now. 77 space agencies around the world now, lots of folks who want to get involved in space science missions but don't have the experience. So we created, at ASU, we created an organization called the Milo Space Science Institute, and it's a member organization like the European Space Agency, and our job is to try to build consortia of universities, companies, space agencies, anyone who wants to do more space science but hasn't had the opportunity. So we partnered with Lockheed and I gave a presentation about how we're trying to put a mission together to Apophis, the potentially hazardous asteroid Apophis.

Mat Kaplan: You've been attending the conference up until this point. Any general impressions?

Jim Bell: Well, I think this has been the first conference, I've gone to several of these, this is the first one where we've got a lot of data being shown from missions that are motivated by planetary defense, like DART, right? And to see actual data from missions that the community has been dreaming about for decades. Let's get planetary defense out there and doing things with missions like we do with Mars and the moon and Venus and Saturn. Let's get some real boots on the ground data going, and it was just so exciting to see those results in great detail today.

Mat Kaplan: Our past President of The Planetary Society for many years, and still very much a member of our board. What I have been told is that our board is a solid believer in the place of planetary defense as one of the major initiatives of The Society.

Jim Bell: Absolutely. It's a pillar. It's such a great combination of fundamental science about the solar system, studying small bodies, the primitive remains of the formation of the worlds around us, and the astrobiology, because these are the objects that bring the organic molecules to the Earth and other planets, right? And then the threat that some of them pose to us as a species, right? It's like you're fond of saying, and Bill Nye often tells us, the dinosaurs didn't have a space program. Well, we do have a space program and we use some small part of our fantastic wealth as a civilization to think about, "Hey, let's take care of ourselves, let's make sure we're not going to get wiped out."

Mat Kaplan: And you know I can't let you go without getting a little bit of an update on what's happening in Jezero Crater, that neighbor to the asteroid belt.

Jim Bell: Yes, things continue to go well in Jezero. As you know, we deposited our first 10 samples in a backup sampling location, and now we're climbing higher up into the delta. We just took a couple of more samples the other day of some of these fine grain delta sediments, so those are very exciting. Ingenuity did its 50th flight. 50th flight, we were supposed to do five, and that's being used as a scout for the rover, so that's great. Our goal is to keep on trucking, keep sampling all these interesting places in that ancient, habitable environment, collect those samples, and get them to a place where the Mars sample return mission can pick them up and take them home.

Mat Kaplan: And let's all hope that there are no big rocks with Perseverance's name on them before it gets its work done.

Jim Bell: Not falling from the sky at least. Exactly. Correct. Yep.

Mat Kaplan: Thank you Jim.

Jim Bell: Great to talk to you, Mat.

Mat Kaplan: On its last day, the PDC moved across Vienna to the beautiful headquarters of the Austrian Academy of Sciences. My wife and I had met our next guest at the previous night's banquet. Alissa J. Haddaji of Harvard University co-led creation of a planetary defense report by the ad hoc working group on legal issues, part of the UN's Space Mission Planning Advisory Group. During that fascinating dinner conversation, we were among the first to learn that Alissa and her dinner guest would soon be married. The conference has just ended in this absolutely spectacular room. When you open a dictionary and look for the word ornate, they should just show you a picture of this room. The PDC is over, any general impressions before I ask you the question that I really wanted to grab you for?

Alissa J. Haddaji: A fantastic conference in an absolutely gorgeous venue. I agree with you.

Mat Kaplan: Yeah. You have played a big part in this. You were up on stage, but what I really want to, and we could talk about anything that's been covered, but what was so intriguing talking with you, especially last night during the conference banquet, are the considerations that surround the possible and maybe necessary use of a nuclear weapon. Maybe I shouldn't call it a weapon, a nuclear explosive, if we're going to protect Earth from one of the larger rocks that may be out there lying in wait for us.

Alissa J. Haddaji: Yes, your point of do we call it a weapon? Do do we call it a nuclear explosive device? What was interesting during this conference is that in the end, it does not make a difference. There will be a nuclear explosion, there will be the launch of a nuclear item, so it can be absolutely considered as a nuclear bomb.

Mat Kaplan: There has been a great deal of discussion here about the legality of that, because use of nuclear devices is specifically prohibited in space.

Alissa J. Haddaji: Yes, absolutely. If you look at the article four of the Outer Space Treaty, or even at the Limited Test Ban Treaty, you cannot send a nuclear device in space. You cannot put it around the Earth. You cannot station it, and you cannot even do a nuclear explosion, meaning that you cannot directly go to your target and explode a bomb without even having to put it around the Earth, because it is going against international law. But there are ways for international law to be superseded by the UN Security Council.

Mat Kaplan: Ways that... These already exist, or would they have to be put in place?

Alissa J. Haddaji: No, these ways already exist. So the UN Security Council can put up a vote to authorize this use of a nuclear device for planetary defense purposes. You would need to have nine of the 15 votes of the members of the UN Security Council and no veto.

Mat Kaplan: This gets into another issue, which is perhaps as sociological and political as legal, and that is the degree of trust that would be needed for the use of these weapons. Because there might be nations who either out of paranoia or realism might be afraid that that missile headed, supposedly headed toward an asteroid, gee, what if it accidentally heads toward my capital?

Alissa J. Haddaji: Absolutely. And you have also two other problems which are that you could have a problem at launch, and this would mean having a nuclear explosion potentially at launch, at the launch site. The second other problem is that because it's banned, you could not test these types of tools currently. So would it be interesting to have it authorized to have a test in space? Well, this already goes against international law, so in the case of a threat, of an imminent threat, you could imagine the UN Security Council authorizing a launch, but this launch might have a problem on site, and might have a problem because we have not tested the technology.

Mat Kaplan: How much of a challenge do you see this as, going forward? Is it something that you think, if and when the time comes, we'll be able to pull this off? Not technologically so much. We know we can do that, I think. But with all these other challenges?

Alissa J. Haddaji: Well, I find the discourse at the PDC very positive. It opens the doors to the social scientists, to the decision makers, to the lawyers, and they're more and more involving them in everything, in all the discussions. And we can see that with collaboration, with coordination, we could have these conversations at higher levels. We could have the secretariat of the UN involved, and being aware of these issues, and potentially making those decisions.

Mat Kaplan: Let's close with coming back to your experience here at the PDC where I think one of the things that has been very gratifying to me, I mean the session that we just watched was about education, both informal and formal education, but the other are the political concerns, the legal concerns, which I think have gotten more attention this year. Is that gratifying?

Alissa J. Haddaji: Absolutely. Hearing people say that, especially in this feedback session that we were just attending, that they listened to the law and policy sessions and were not bored. To us it's a victory, because we want to make these legal discourses accessible to the public, because we want to involve them. We want to hear feedback, we want to understand who we are talking with, and not who we are talking to.

Mat Kaplan: Why is this planetary defense a topic that you put so much passion into?

Alissa J. Haddaji: There is nothing more uniting than looking at how to protect the Earth from a large asteroid. We are all involved and it's my hope that in these situations where every single human being would be impacted, no matter how large the object would be, that they would be a push for international collaboration.

Mat Kaplan: Let us hope. Thanks so much.

Alissa J. Haddaji: Thank you.

Mat Kaplan: We'll close with an old friend. Nahum Melamed of the Aerospace Corporation was one of several chairs of this year's conference, along with conference founder Bill Aler, his former colleague at Aerospace. Nahum, the conference has just ended in this gorgeous room. Are you happy looking back on this, moments after the close of the Planetary Defense Conference?

Nahum Melamed: I am. I'm very happy. I think it was a great success. After about a year of preparation, of monthly and weekly meetings by the organizing committee, we can declare it a success. I learned a lot. I met some old friends and new friends, and I think that we have some plans for the next conference, which we want to hold around the globe. We want to hold a conference that we will have an outreach to areas that we are not covering to date. This is one of the lessons learned from those last few conferences. We need to engage the local communities. Local communities can spread the word across the wider communities globally. And because this is a Planetary Defense Conference, we need to engage in the planet.

Mat Kaplan: Spreading the word, the educational element here, which was the topic that we just finished, the last of the formal sessions here at the PDC, very close to your heart. I know, because you've been doing this in outreach to lots of young people.

Nahum Melamed: I've been doing it. It started with my own son. Start at home, educate your kids, and they will go into huge prolific trades. And I give talks to thousands of young minds. I look at their eyes and my goal is to expect them running after me and say, "I want to be an astronaut." If I did that, I am successful. So when I hear that, I look at their eyes, I know that they're in, they are inspired, and one day they will be the next generation of planetary defenders.

Mat Kaplan: And your son is a good example of that. I didn't have the chance to tell him, maybe I will if I see him later, that his presentation was both fascinating and very well delivered. So good on you passing it on to the next generation.

Nahum Melamed: I think this is my mission. This is my calling to pass my knowledge and my inspiration to the next generation, both at home, in my neighborhood, and in my wider community worldwide

Mat Kaplan: Nahum, I hope to see you at the next PDC. 2025?

Nahum Melamed: Yes, 2025. It will be our next PDC. We don't know where it's going to be held. We hope that we'll find a nice exotic location. We'll know for sure in the near future. And I'm looking forward to PDC 2029, to look at an asteroid that's passing above our head. That's going to be a once in a millennia.

Mat Kaplan: Here's to Apophis, and the awareness that I'm sure it's going to bring to planetary defense on planet Earth.

Nahum Melamed: Cheers and amen to that.

Mat Kaplan: I hope I'll still be around and allowed to attend the 2025 Planetary Defense Conference, as our progress toward defending Earth from near Earth objects accelerates. As Bill Nye says, we're just trying to save the world. For Planetary Radio, I'm Mat Kaplan of The Planetary Society.

Sarah Al-Ahmed: I'm so glad that Mat is continuing to have awesome space adventures in his new role as senior communications advisor here at The Planetary Society. It's awesome to have him pop back onto the show. Now let's check in with our Chief Scientist, Bruce Betts, for What's Up. Hey Bruce.

Bruce Betts: Hi Sarah. Really good to see and talk to you.

Sarah Al-Ahmed: Yeah, you too. And here we are in the United States, not having fun adventures in Vienna with Mat and Casey. So we have to have our own adventures.

Bruce Betts: We're way more fun.

Sarah Al-Ahmed: What's going on in the night sky this week?

Bruce Betts: All right, night sky, bright Venus, of course, still over in the west, unless it's cloudy, in which case go inside. It's the brightest star like object. Can't miss it. Mars is significantly above Venus, looking reddish. Be kind of fun over the next several weeks, watch Mars and Venus get closer together. Very exciting as Mars drops lower. And it will also be passing through Gemini, and will be hanging out near the twin stars of Gemini, Castor and Pollux over the coming weeks. And in fact, they make a nice line on May 15th with Mars, Pollux and then Castor and then down below them is Venus. May 5th is the peak of the Eta Aquarids meteor shower, which is better than average usually, but it's a full moon this year, so that'll wash out a lot of them. It is better in the Southern Hemisphere than the Northern Hemisphere. It's good for several days before and after, or it would be if it weren't for that pesky moon. May 5th is that peak. Oh, pre-dawn, I forgot, people wake up in the pre-dawn. Or stay up until then, you can see Saturn looking yellowish getting higher and higher over in the east, and Jupiter's starting to try to come up, and it'll be coming up over the next few weeks. Very bright Jupiter in the east in the pre-dawn. There we go.

Sarah Al-Ahmed: We did it.

Bruce Betts: Yay. We move on to this week in space history. 1961, Alan Shepherd becomes the first American in space with a suborbital flight. And 20 years ago, 2003, the Japanese launched Hayabusa, the first asteroid sample return mission. And they've done Hayabusa 2 since then, and it's cool stuff. Speaking of cool stuff...

Sarah Al-Ahmed: Gesundheit.

Bruce Betts: Thank you. So did you ever wonder why is JPL located where it is? Maybe not, but here's the answer. It's because Caltech crazed grad students under Theodore von Kármán, were looking for a safer place than the campus to do dangerous rocket experiments. And they settled on the Arroyo Seco, a mostly dry small canyon area, and they did crazy dangerous stuff up there. And their JPL was built next to Arroyo Seco, basically as a result, because that turned into the core of what would eventually become JPL.

Sarah Al-Ahmed: Who would've thought that not being able to play with rockets in your dorm room would have such an impact on the future of space?

Bruce Betts: I mean, it's really more of a guideline than a rule. All right, we move on to the trivia contest and I asked you where in the solar system is the best place to go if you want to find sulfur dioxide frost, with best judged by me, if there's any question, how did we do?

Sarah Al-Ahmed: Thankfully we didn't need you to regulate too hard on this one because most people got it right. The answer is Io, that super duper volcanic moon of Jupiter.

Bruce Betts: Indeed, it spews out plumes of sulfur dioxide that go up hundreds of kilometers, and then freeze out and fall as the frost, and form the white stuff that you see in the pizza moon's pictures with all of its multiple colors. The white is often sulfur dioxide frost.

Sarah Al-Ahmed: I love that you call it the pizza moon, because a lot of people wrote in to call it Pizza Moon. But our winner this week is John Hernandez from Colorado, USA and you get a copy of Phil Plait's Under Alien Skies. So I'll be sending you my personal copy that I got, which is awesome. I love too, so many people, anytime you talk about Io, everybody writes in to say Io, Io, it's off to work we go. A whole musical number in almost every single message, so that that was lovely as well.

Bruce Betts: Wow. Didn't expect that.

Sarah Al-Ahmed: I liked this message too from Randall Henderson in Oregon, USA, who said, "It's definitely the best place, especially since you didn't say safest or at least likely to horribly die on."

Bruce Betts: That's true. That was not part of the question.

Sarah Al-Ahmed: That was not. I don't know what would be the safest place to do that?

Bruce Betts: A laboratory on earth, but I also ruled that out.

Sarah Al-Ahmed: Just make sure you don't do it on campus.

Bruce Betts: Yeah. And then there'll be a place that does space stuff in the future. I get it.

Sarah Al-Ahmed: All right, so what's our question this week, Bruce?

Bruce Betts: Well, I went to quality high class stuff this week. What's the official name or the official designation for NASA's toilet on the ISS, the International Space Station, also to be used on Artemis 2? Go to That's kind of an old bonus random space fact that, same basic design.

Sarah Al-Ahmed: Because the original question is pretty funny, but I did not know that it was the same one on Artemis 2. That's super funny.

Bruce Betts: There's nothing not funny about excrement in space.

Sarah Al-Ahmed: Well, all right, you have until Wednesday, May 10th at 8:00 AM Pacific time to get us your answer, and whoever wins this week is going to get themselves a Stay Unextinct sticker, from our Planetary Society Chop Shop site. Get yourself a cool little sticker with the dinosaur. Remind yourself that planetary defense is important, because ain't nobody got time for going the way of the dinosaurs.

Bruce Betts: This is so true. Stay unextinct everybody. All right, everybody go out there. Look out the night sky and think about three little fishies swimming in a pool. Thank you, and goodnight.

Sarah Al-Ahmed: We've reached the end of this week's episode of Planetary Radio, but we'll be back next week with updates from the world of space science and exploration. Planetary Radio is produced by The Planetary Society in Pasadena, California and is made possible by our Earth defending members. You can join us as we continue to push for planetary defense missions at Mark Hilverda and Rae Paoletta are our associate producers. Andrew Lucas is our audio editor. Josh Doyle composed our theme, which was arranged and performed by Pieter Schlosser. And until next week, ad astra.