Planetary Radio • Apr 29, 2020

Life on Mars: Joining the Quest with Penny Boston and Jim Green

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Penny boston

Penny Boston

Cave and Planetary Scientist

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James Green

Senior Advisor to NASA and host of Gravity Assist

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Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

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Mat Kaplan

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

Mat Kaplan recently hosted the first of a series of Explore Mars live and interactive events. NASA astrobiologist Penelope Boston and NASA Chief Scientist James Green joined him for a thrilling conversation about the search for life on the Red Planet, and what may happen if or when we find it. The comet may be a bust, but Bruce Betts tells us there’s still plenty to see in the current night sky. Mat and Bruce also talk about the first ever What’s Up Live!

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NASA Perseverance rover (artist's concept)
NASA Perseverance rover (artist's concept) This artist's rendition depicts NASA's Perseverance rover studying a martian rock outcrop.Image: NASA / JPL-Caltech

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Mat Kaplan: [00:00:00] We found Life on Mars. Now what? This week on Planetary Radio. [Music]. Welcome. I'm Mat Kaplan of the Planetary Society with more of the human adventure across our solar system and beyond. Hoping you and yours are staying well. No, you didn't miss the biggest headline of the century. Finding Life on Mars is still just the goal and dream of millions including our two great guests. Penelope Boston is a world renowned astrobiologist and would be Martian. James Green is Chief Scientist at NASA.

They recently joined me for a live conversation sponsored by Explore Mars and you'll hear most of it in minutes. Then we'll drop in or drop up or a visit with another chief scientist, our own, Bruce Betts. Here's a reminder that you'll be able to join Bruce and me for the first What's up Live on Thursday, April 30th. More information and a player are at [00:01:00] Here we go. NASA and SpaceX have set the 27th of May as the launch date for SpaceX's, Crew Dragon, to carry astronauts, Bob Behnken and Doug Hurley to the International Space Station.

The milestone launch will be the first carrying humans from Florida since the end of the Space Shuttle Program, nine years ago. Planetary Radio and will provide coverage leading up to this big event. That's just one of the stories you'll find in this week's downlink from the Planetary Society. Here's more. NASA's OSIRIS-REx space graph completed a sample collection rehearsal at asteroid Bennu coming within 75 meters of the surface before backing away as planned.

The probe is scheduled to actually touch down in August when it will grab a small sample of regolith for return to earth in 2023. Japan's Hayabusa2, now on its way home from asteroid [00:02:00] Ryugu, arrives late this year. And CHEOPS, the European Space Agencies characterizing exoplanet satellite, has observed it's first distant world. The target was a puffy gaseous planet, 30% larger than Jupiter that is orbiting a star 320 light years from us.

CHEOPS is designed to precisely measure the diameters of known exoplanets, which will also reveal more about their compositions. You can get more at including a free subscription to the weekly newsletter. The Planetary Society isn't the only space organization that has turned to the web as an alternative to, in person events, during these crazy times. Our sister organization, Explore Mars, has also begun an ambitious series of live interactive discussions.

It was my honor to host the first of these for them on April 1st. The topic was Life on Mars Implications and Impacts. [00:03:00] Penny Boston, Jim Green and I, talked about the status of the search for life on the red planet. What format life might take? Where we may find it? And perhaps, most dramatically, what may happen when we discover we are not alone. We've got a link to the complete video on this week's show page at including the great slides Penny and Jim presented and the audience Q&A segment that I've omitted here to save time. The audio quality of what you're about to enjoy is not up to our usual standard but I think you'll find the conversation as fascinating as I did.

Let me set the stage for today's conversation with a hypothetical. We've jumped forward to 2024. A rover named Perseverance, that we'll be talking more about momentarily, has been rolling across Mars for three years. Another visitor from Earth, a more recent arrival, named Rosalind Franklin has been pulling up samples from below the surface of Mars. NASA and [00:04:00] the European Space Agency have just announced a joint press conference that is going to reveal images and other data indicating that we just may have found strong evidence of life. Will this news, as my boss Bill Nye likes to say, change everything? What do we do next and how will it affect plans to send men and women to Mars?

But I'm getting ahead of myself. So hold that thought for now as we meet two very distinguished guests that will be joining me here. I really can't think of anyone else. I would rather have, uh, onboard to talk about this topic. Beginning with Dr. Penelope Boston. She is the Senior Advisor for Science Integration at NASA Ames Research Center in Silicon Valley. Penny's personal expertise is the geo microbiology of extreme earth environments, especially caves and mines and astrobiology. As a lifelong human space exploration advocate, she co-founded the Case for Mars [00:05:00] conferences in the 1980s and 1990s. That makes her a founding member of the Mars Underground as well.

She's a member of Explore Mars. She looks pretty great in a fake space suit. She earned her Ph.D. in Microbiology at the University of Colorado Boulder. She was, till recently, the Director of the NASA Astrobiology Institute based at Ames. And as a former Professor and chair of the Department of Earth and Environmental Science at the New Mexico Institute for Mining and Technology. Also, the former associate director of the National Cave and Karst Research Institute. Welcome Penny.

Penny Boston: Thank you. Great to be here.

Mat Kaplan: Dr. Jim Green is the NASA Chief Scientist. He received his Ph.D. in Space Physics from the University of Iowa in 1979 and has worked for NASA ever since. That included 12 years as the Director of the Planetary Science Division at NASA Headquarters. Under his leadership, more than a dozen planetary missions were successfully executed including the Curiosity rover and Insight Lander [00:06:00] both of which are still quite active and delivering great science on Mars. Jim is NASA's representative on the COSPAR Planetary Protection Panel where Planetary protection guidelines are created and agreed to internationally. COSPAR, that's the, uh, Committee on Space Research. In 19, excuse me. 1915? You're not that old, Jim.

Jim Green: No, I'm not. [Laughing].

Mat Kaplan: In 2015, Jim coordinated NASA's involvement in one of my favorite movies, The Martian.

Jim Green: [Laughing].

Mat Kaplan: Talk about infecting a planet. By the way, he also hosts the excellent NASA podcast called Gravity Assist. Welcome, Jim.

Jim Green: Thank you very much, Mat. I'm delighted to be here.

Mat Kaplan: So let's back up a little bit and talk about the current status of Explorer, Exploration on Mars now and what's going to be happening there, well, in less than a year now with [00:07:00] the arrival of this new rover, uh, tell us, eh, what's the status of Perseverance?

Jim Green: Well, Mat, Perseverance is actually moving forward. Uh, it's all down at the Cape and in fact, uh, the radio isotope power system is already connected. Uh, it's checked out in many ways. It still has a number of things to do yet but we're making great progress. So it is on track for a July 17th open window for us to be able to launch. And that's when that highway opens up for the next three weeks that can get us to Mars.

Mat Kaplan: This is like a-almost everything NASA sends to, uh, around the solar system nowadays and international efforts, right?

Jim Green: It is and indeed. This particular rover has got, uh, fabulous set of instruments where we have participation from uh, Spain on a, on a weather system. Uh, we have, uh, Norway having a ground penetrating radar. We have the French working with us on, uh, some [00:08:00] really great cameron and laser systems. And we have an Italian retro reflector. But the whole point of this particular mission is, really, at the end of the arm, this is where we have high resolution images that we wanna be able, uh, to really look at the rock record and then make decisions in terms of creating cores. It's got a core at the very end of it.

Uh, what these cores look like, it's a, they're like a piece of chalk in size or, or for those that are young enough that don't really understand what, uh, you know, chalks and chalkboards were all about and their education. Uh, l-like a crayola cram, you know, one of the large sizes. Once those cores are made they're, they're stuck indeed and, and to an aluminum sleeve and then dropped on the surface for then later pickup and bring back.

So by the end of that decade, uh, the 2020s, we [inaudible 00:08:55] to be able to have these samples back in our Bio [00:09:00] level 4 facility and begin the process of really looking through them to determine, uh, their viability and allowing scientists to get access to them for further research. So we're doing great.

Mat Kaplan: And even though she resembles her sister on Mars, Curiosity, you've given at least a couple of examples in that image and with those cores, especially, of the new capabilities, the Perseverance is bringing to the red planet. Pretty powerful machine, isn't it?

Jim Green: Oh, it absolutely is. And the rock record is so important to us, you know. We know that Mars was, uh, a blue planet early on in its history. It went through rapid climate change. It was a blue planet during the time we know Earth had, uh, life started on it. And so maybe life started on Mars too. And so we're really quite excited about going there and interrogating that, being able to bring back those samples and look at them. You know, for all the minerals we have here on Earth, there are hundreds of minerals for [00:10:00] which life is such a key part of that create those minerals. And, you know, so if we can find the right set of information, indeed that press conference you talked about would be really lively.

Mat Kaplan: So Sample Return. And you know, I often refer to it as the Holy grail of robotic exploration of, of Mars and could be for other places as well.

Jim Green: This was how we, uh, envision right now working with our international community to be able to get those, uh, samples back and it all requires a NASA landing, a Mars ascent vehicle. We then have fetch rovers that pick up those samples that we laid on the ground and deliver those. And then we launch off of Mars, those samples, in a, a container and then that container goes into orbit for which then ISRO satellite, uh, will come down using, uh, ion propulsion into lower, low Mars orbit. Pick those samples up and then bring them back to Earth. It's indeed a, a [00:11:00] multinational effort and, uh, the planning is going real well.

Mat Kaplan: Penny, y-you're a long time Martian. What's it going to mean to scientists like you to get those samples back here and into our n-nice big labs on Earth?

Penny Boston: Well, you know, uh, as you say, uh, Mat, it's been a Holy grail for many decades and uh, pretty much my whole career. I'm sure that's true for a lot of us. The opportunity to actually get our lab facilities here on Earth to bring all of their power to bear on samples is a new step really, in, in marching forward to be able to analyze Mars materials. Uh, the missions that we've had so far and the ones to come are magnificent. But there's this only a certain amount that you can s-smash onto a spacecraft and a lander and a rover, uh, before you run out of power and mass and all of that. And so the ability to do [00:12:00] these really in detailed studies of the geochemistry, the mineralogy, the f-foundational bedrock materials. Perhaps even some of the, uh, fine materials on Mars, will give us, uh, insights into, uh, the climate history of that planet which is very important to our understanding of climate in general on our own planet and beyond. And also potentially allow us to look at organic materials and various other things that may be significant for the potential history of any life that may have arisen on Mars.

Mat Kaplan: Jim, I wanna get back to you. I gave short shrift to all of the success we've already seen on Mars with, uh, two active spacecraft on the surface and that flotilla, uh, on orbit above the planet. Where are we in what we've learned? I mean, we found the water. Are we still following it? A-And what else have we found?

Jim Green: That's a really great question in the sense that, uh, you know, there are more, there's more to it than just [00:13:00] following the water. You know, we've seen evidence of water all over the place on Mars that's clear. Uh, we've seen what we call, a recurring slope lineae where, uh, water may actually be pouring down the sides of craters in a seasonal way. Uh, this is, uh, during a time period during, uh, indeed that summer. Where su-, where the sunlight shines on the crater walls, perhaps it sublimated, uh, water plug that's sitting, holding back water in an aquifer and then that water pours out and runs down the slopes.

We've measured that. We know it's water. Now, some of these actually may be drifts of, uh, of dust and, and, and therefore producing some discoloration. But there's so much of it and there's so many places where, where it's occurring. You know, we're pretty convinced that, uh, that indeed there is, uh, a significant amount of water locked inside the planet. Now, in addition to that, Mars seems to be emitting [00:14:00] what we would call, traces of life gases like methane and like oxygen-

Mat Kaplan: I'm knocking on wood.

Jim Green: Yeah. Right. [Laughing]. And indeed, uhm, although those things can be generated, A, biotically, for the methane, we've been observing methane from telescopes on earth since the early 2000s, uh, but now with curiosity, making those measurements directly over and over again, we do see that seasonal bloom, what we'd call, uh, this rush of methane coming out. Although it's still a trace gas, you know, parts per billion we're talking about that is coming from underneath the surface.

Now, that could be generated, A, biotically. It requires water, r-requires certain minerals and a heat source like magma or it could be old methane from old life in the past that is also been trapped over time and is, is being released. Or [00:15:00] indeed it could be an indication of life there today. In the aquifers is what we would think. So those trace gases now are extremely important. We're making fabulous measurement of those.

Mat Kaplan: Both for methane and oxygen, there've been some conflicting data, hasn't there? Uh, depending on the observer?

Jim Green: Yeah. Indeed, uh, the oxygen observations that we just released over the last several months is a, is a long-term trend. It's about five years worth of observations. And it's a surprising trend. You know, as the planet goes through, it's a seasonal cycle. Uh, we expect during the winter because it's so cold that a lot of the atmospheric gases in particular, the trace gases will collapse down under the surface. And then as it warms up, it, it, it actually then, uh, releases those. And what we're finding is an excess of oxygen during, during certain times. And then at other times we see that the oxygen actually is being removed.

[00:16:00] So this has really caused quite a puzzle. We've had many scientists really working, trying to figure out what are the, A, biotic, in other words, the non-biological rea-reasons that this is, uh, happening and we really haven't come up with a good explanation. So the oxygen observations are really one we wanna stay abreast of and see what curiosity is gonna find in the future.

Mat Kaplan: Penny, have we seen evidence other than what Jim has just talked about that could i-indicate biological activity or at least past biological activity up there?

Penny Boston: Well, you know, so far we haven't had the opportunity to closely examine materials getting back to our previous discussion about, uh, Sample Return. But what we have been able to do, of course, is hookup what we understand about extreme environments on Earth and try to tease out the parts of those environments that are relevant to Mars. It's pretty clear we have [00:17:00] nowhere on earth that is just like Mars, that's a very, very challenging environment. But we have challenging environments on Earth that have components that really go into that Mars picture.

And so, uh, microorganisms in their vast diversity, they're unbelievable diversity on this planet have adapted to, you know, wild variety of conditions. Many of them are the conditions that we see in the Mars surface. And particularly of course from my point of view as someone very interested in, in the subsurface, both near and deep subsurface, where there's more protection from some of the nasty things that you get on the, on the Mars surface.

So I think that the importance of the gases that Jim has just been articulating is really because the atmosphere of a planet is its breadth, essentially. And the breadth of life, uh, on earth is very, very clear. We have a very complicated atmospheric, uh, spectrum, which [00:18:00] is, the sum total of all of the complex gases that life on our planet puts out. When we're looking at a planet like Mars, if we're looking at life that has been, not as raw, globally, as it is here on earth for a long time, that is something of a Relic Biosphere.

Then we would expect to see a much more subdued signal. But the fact that there is this oxygen, um, uh, variability and the fact that we see these traces of methane, are very exciting. Because what that might say about life is that, if it exists in a subsurface, there's a certain leak rate just like we have with spacesuits and spacecraft and Earth itself. And uh, that we may be catching little rifts of what's going on underneath. In any case, whether or not it's biology or it's non-viable biology. When you have, uh, a, a life bearing solar system like ours, in my view, every planet matters to understanding that life even if that life only [00:19:00] occurs on one planet. And of course we certainly hope that it occurs on Mars or has occurred on Mars as well as other places in the solar system.

Mat Kaplan: Much more of my conversation with Penny Boston and Jim Green is only a minute or so away.

Kate: Hi, this is Kate from the Planetary Society. How does space spark your creativity? We want to hear from you whether you make cosmic art, take photos through a telescope, write haikus about the planets or invent space games for your family. Really, any creative activity that's space related. We invite you to share it with us. You can add your work to our collection by emailing it to us at [email protected]. That's [email protected]. Thanks

Mat Kaplan: Penny. You have spent a good part of your life going to places most of us would not wanna go, uh, looking for how life has found a way to survive. Uh, one of those more milder locations. I remember being with you, Carlsbad Caverns and [00:20:00] you pointed to a spot on the wall and you said, "You see that? That's life eating copper." So it does sure look like the enormous variety of extremophiles that we find on our planet. It's gotta give you some encouragement, right?

Penny Boston: Oh, very much. Even though I, I'm a Mars fan for my entire life, of course I have an eye on the other potential habitats. And I think that the fact that we have organisms that appear to be able to tolerate almost everything, uh, including high radiation and organisms that have been retrieved from, you know, space exposure and complete desiccation. And, um, living amongst metals that we find toxic but, uh, they're busy using inorganic chemistry to make those into energy sources. Um, makes me really understand the, the sweep of what our type of life. Meaning organic carbon, you know, water matrix is [00:21:00] capable of. It's really quite extraordinary.

Mat Kaplan: Life as we know it. Yeah.

Penny Boston: Yeah, life as we know it. And of course, you know, many of us consider life as we don't know it and that life as we don't know it extends to other ways of making life even out of organic carbon. So there're, there're people thinking about other alternative sets of chemistry that might work on other planets. But from the point of view of Mars, my conviction is that we're really looking for carbon based life, uh, in a water matrix because Mars is not all that different from Earth.

And certainly as Jim pointed out, early in its history, it was much more similar. And so that early childhood of our rocky terrestrial planets together, uh, seems to me very significant. And even Venus in its current state which is quite inhospitable to life as we understand it. Uh, but its early history may have also shared in, in, uh, habitable zone. [00:22:00] So it's not, not just Mars alone that is compelling but really Mars, as this beautiful red jewel, within this entire spectrum. This entire crown of jewels that we have in our solar system and, and what they offer for life.

Mat Kaplan: Have your, your studies and, and what we've learned from others in looking for biosignatures, that, that key term. Has it led you to the point where you think that if we had life staring us in the face, we would, we would recognize it?

Penny Boston: Well, yes, maybe. Uh, the slide that was just put up shows a variety. And, uh, this of course is for my, from my own work. Um, all of these colorful and drippy gooey things that you see are all examples of microbes as tiny as they are but making major changes in the rock and mineral environments that they live in. They orange stuff that you see that looks sort of like a pizza or the surface of IO, uh, [00:23:00] that's all rock breakdown material that's been chewed through by organisms that use manganese and iron. Uh, rather than, you know, eating hamburgers for lunch, they eat rock.

Mat Kaplan: Wow.

Penny Boston: And they use those minerals and then they poop out, so to speak, uh, all of this fluffy stuff. And so they're, you know, they're major geological agents on Earth but it shows that they can make their living off a geological source. You can see the screaming blue patch that one of my French colleagues is standing by sort of in the middle, uh, lower part of the, of the screen. And you can see an example of the same process. You were talking, Mat, about the copper material that I showed you. These are organisms all over the world.

They're different and very unrelated but they still are able to do the same thing. And so that makes me even more excited because it doesn't have to be the same organisms. It's finding a pathway of organisms in different places that can use the same [00:24:00] energy sources. And so, to me, that seems like an encouraging, uh, sign for extraterrestrial life.

Mat Kaplan: [Sighs]. Jim, on a jump back now to that hypothetical that I posed of the outset. That press conference which you would very likely be a part of, as I hope you're still on the job in 2024. You've got big news for us.

Jim Green: Right.

Mat Kaplan: What's this going to mean if indeed we find evidence better than we've gotten in the past? I'm thinking of a certain, uh, meteorite ALH84001, that, that seems hard to argue with that maybe we have found at least evidence of past life on Mars. What's that going to mean to us here on earth?

Jim Green: Well, let me just mention. Of course, um, uh, there is, um, uh, an important aspect of thinking about that future when we start that announcement. And that really boils down to looking at what's happened in the past by analogies. The ALH84001 is a good one in the sense that we would organize that [00:25:00] press conference. Uh, on that press conference, we would have, uh, the, the scientists that a-are announcing the discovery but also scientists that are a little skeptical. That announcement then would go out to the public and then there would be a period where the community of scientists would really dig into the results.

Perhaps, um, if we've returned samples, uh, soon after that they would then be able to have those in the laboratory, uh, et cetera, and really tease it out and then public reaction. And then an education has to go on to everyone in terms of the context of what, what this means. But if we just take that supposition that indeed in the long run it proves to be true and we have found that second Genesis and it is on Mars, what does that mean? And here by analogy, I think, uh, we have to look at perhaps, um, several. One, one comes to mind, is what Copernicus did.

At the time Copernicus was, uh, coming out with a theory that the planets went [00:26:00] around the sun and that everything went around the earth. It changed the world view. Everyone, mentally, had to now rearrange their thoughts about their place in the solar system in the universe. And it had a profound effect. People thought, well, we are the center of the universe because everything goes around us and now they go around the sun just like the other planets. And then, to them that means, well, maybe there are other societies like us on other planets. This was really profound change.

I think, indeed, we're gonna have to come to grips with that. Many people, uh, because of our literature and our movies are, you know, all set to accept that there's a second Genesis out there. And in fact many scientists and that would include me, think it's almost inconceivable that there isn't some sort of life out, not only in sources but certainly is certainly o-on other planets. And so our worldview [00:27:00] then, once again, will have to change. And I think it will change many different things. The, the results of finding microbes might be as revolutionary as cracking DNA. You know, the concept of what, w-what's come out of microbiology, which is only a handful of decades old, has just been phenomenal. That is awaiting us with this kind of discovery if we do indeed find microbial life on Mars, I think,

Mat Kaplan: [Sighs]. Penny, what would this mean to you and, and your colleagues, this announcement and the provision of this data?

Penny Boston: Well, you know, I spent my entire life doing this and so have many of my colleagues. So [laughing] I, um, have dreamed about that happening in my lifetime. I hope it does. I'm trying to stay as healthy as possible to get the maximum chance.[Laughing]. And um, you know, the minute [00:28:00] we got any kind of indication that there might be extent life or even extinct life, okay? Cause I also do paleomicrobiology and I'm interested in the entire deep history of planets with life. The entire community would go into a frenzy of trying to test whatever features this potential life would have. And so there would be an enormous, uh, flourishing. Uh, maybe in directions that were already pursuing, maybe a new direction. So it depends on what those results would find. And then I would throw one heck of a big party.

Mat Kaplan: [Laughing].

I'd like to attend that.

Penny Boston: [Laughing].

Jim Green: [Laughing].

Mat Kaplan: [Laughing]. Please invite me.

Penny Boston: I will.

Jim Green: [Laughing].

Mat Kaplan: Um, we should get into a, the topic that topic maybe our, our sponsors here that explore Mars are most interested in after all, they are the humans to Mars people. And that is, what, uh, the possibility evidence for, not just pass but [00:29:00] possibly existing life on Mars stuff that's still kicking up its heels there today, would mean for sending humans there? Jim, you were a, a, a big contributor to that movie, The Martian.

Jim Green: Yes. [Laughing].

Mat Kaplan: I would not be a good idea for us to head there and, and plant coop potatoes, would it?

Jim Green: Uh, uh, uh. No. Actually, Curiosity has found the, the nitrogen, oxygen, uh, carbon, phosphorus and sulfur on Mars. All the right stuff. The soils are, are moist and indeed, um, uh, there's nitrates in the soils. Now, where Curiosity is sitting, turns out to have alkaline, uh, soil's, not acidic. So what would grow better here would beans and, uh, asparagus. And, and, and I don't know about you but if I had to e-e-e-eat two or three years worth of asparagus, I'd just take my helmet off and walk outside.

Penny Boston: [Laughing].

Mat Kaplan: [Laughing].

Jim Green: But I-I'm assuming, I could do the potatoes. I'm assuming, we all are assuming there'll, there'll be more acidic soils to elsewhere. And so [00:30:00] indeed the analogies between Mars soils and Earth soils is really strong. That's, uh, really quite important. If we found evidence, uh, for current life, uh, that current life, uh, has to be below the surface. We haven't found evidence of life on the surface. And for human exploration, uh, I think we'd have to talk about how we're gonna share Mars and I think we can share Mars.

There are many, uh, approaches unlike the Martian where, uh, the concept was, you land Ares 1 and the next time it's Ares 2, Ares 3, Ares 4. We would plan to go to one particular area, perhaps, uh, 150 or 200 kilometer area called an exploration zone where we land in one part, live in another part and then have the ability of mobility to go around and perform a whole variety of scientific experiments but really confine ourselves to that part of Mars.

And in so [00:31:00] doing then, it gives us a wonderful opportunity, perhaps over several decades of, of continuing to go there and continuing to build and develop things at that site. And opportunity to really learn and obtain a deep understanding of what Mars is all about. And then we can take it to the next step with that kind of knowledge. So I'm all for sharing Mars.

Now, you may know that many scientists, particularly, Carl Sagan, thought that if we found microbes on Mars, we need, uh, to leave Mars alone and go to the, go to another body in the solar system. But, um, I think because life also has to evolve over time, the evolution of that life is going to be completely different than ours. And that gives us, I think, an opportunity to coexist. And, and those are some of the new ideas that are coming out now.

Mat Kaplan: Penny, what's your view about all this? I mean, I think you wanna see boots on Mars as well. But, um, you-

Penny Boston: I'd like to see my boots on Mars [00:32:00] actually.

Jim Green: [Laughing].

Mat Kaplan: [Laughing]. Me too.

Penny Boston: But I'm going to be too old, I'm afraid. But, um, i-i-it's something I've wrestled with my entire career because I have this, uh, desire for exploration for our species to go beyond other bodies in our solar system. And who knows, someday even out of our solar system in some number of hundreds of years. But at the same time, of course, I'm very, uh, very aware of the deep ecology aspects of another biosphere. And this applies to Mars or any other biosphere that we may find in our solar system.

And that is, how do we study it? How do we, perhaps, co-habit with it as Jim points out without doing damage to it? And in turn without doing damage to us. I think that many years ago, probably 25, when I first started writing about the Mars subsurface as being the best place to look for, uh, life on Mars, it was not taken very seriously. Well, we knew a lot less about the planet at that [00:33:00] time but we've plugged along on that theme and I think it's become manifest that, that is the place. As Jim says, uh, where we would have the highest chance of finding subsurface, uh, life, even if Mars once was covered in life at the surface.

That the subsurface, in many cases, particularly even on earth, is a refugium, a refuge for organisms when circumstances change on the surface. We see this in microorganisms and macro organisms. So there are caves with fish and invertebrates that have been separated for 20 million years from the surface and things of that sort. So I think that the expectation that I have is that any Mars life is going to be quite deep. And that helps us with this conundrum. Because as long as we don't contaminate aquifers as we're trying to get resources for human use then the surface Mars environment is [00:34:00] very harsh.

And while I wouldn't call it entirely self sterilizing, it will do a lot to reduce the plume of biological contaminants within some distance from, uh, a human colony. And then of course if we want to study things like the slope lineae, these trickles of water, a briny water that Jim mentioned early on in our, in our discussions, those are juicy targets literally and figuratively. We can't wait to get our hands on that but our hands will not be our hands. Our hands will hopefully be sterilizeable robotic sampling devices that we'll be able to send out and bring those samples back for analysis. So there are ways to do this and you know, we're living through it now. Uh, with this pandemic that we're all experiencing, how do we separate our activities from, in this case, a pathogen but in the case of humans on Mars, how do we se-separate ourselves from potential organisms [00:35:00] that are the margins and keep all of us safe?

And so, uh, all of these real world things are being worked out in real time. And as, as, uh, where you mentioned that Jim is on the COSPAR panel, that dates back to the, uh, 1950s and the early part of the space age. So it's not like we just discovered that, oh, gee, there might be a problem. Many of us have served on panels and workshops and, uh, we're writing about it all the time. So, uh, it's very, very much foremost in our minds about how to do this safely. I think we can do it. I hope I'm not being naïve.

Mat Kaplan: Jim, I'm, I'm really glad that Penny brought us back to that COSPAR committee that, that, uh, where you are the Planetary protection representative from NASA, from the United States. How is this being considered by the international community? These, uh, questions are protecting Mars but also wanting to go there and like have humans explore?

Jim Green: Well, indeed, uh, uh, COSPAR over the years has, uh, looked at each and every one of the [00:36:00] bodies in the solar system that were, uh, being considered by space agencies to go to. And indeed early on, we didn't know much about the moon in terms of, uh, uh, whether there'll be pathogens there. And so consequently, those guidelines that came from the COSPAR committee, that, uh, the international community signed up to, meant that we, for, for a NASA perspective, wanted to implement a quarantine system.

So when samples came back from, uh, Apollo 11, you know, the astronauts went into quarantine and the samples went into quarantine. And then we went through our processes of indeed interrogating those and understanding what they are, what we had whether there were pathogens, et cetera, uh, watching the astronauts over a period of time. And then finally, uh, r-r-recognize that indeed we could, uh, have uncontained sample returned from Mars we didn't need to go through the [00:37:00] quarantine process.

And so then, that means the guidelines were revised. So the committee, indeed, takes it very seriously that as we learn new things about each of the bodies that, that the space agencies are planning to go to, we take that into account to modify those guidelines. And that's been working really well. In fact, just recently we took a good look at, uh, Phobos. And we recognized, uh, that Phobos indeed, one of the moons of Mars, we could actually back off some of the more stringent guidelines on returning samples. And so we've categorized Phobos as our location where we can have unrestricted earth return of those samples. And the, and the Japanese-Jackson mission is, is being planned, uh, to go there and has many international connections and components to it. But that required for us to bring all the knowledge we knew about Phobos forward. And not consider it like Mars [00:38:00] in a category of more restriction. And so we're gonna continue to do that. And that process is working well.

Mat Kaplan: Penny, you touched on it. But it's the question that Explore Mars, our CEO, Chris Carberry posed before we started this. And that is whether what we have learned, uh, about both, how we might handle isolating ourselves from life on Mars or anything else in the field of astrobiology might've helped prepare us to deal with the challenge that we're facing around, uh, this planet right now. The, uh, the pandemic. I mean, do you see any relationship there?

Penny Boston: Yes, I, I, I do. I think that, um, one of the things that this horrible circumstance will maybe help is eventually in better public communication. You know, when you are trying to talk to people who are not microbiologists or scientists of some other sort about microbial life, it's very hard to communicate the size of [00:39:00] these individual entities, their capabilities and just how easily spread they are. You know, in many cases that's very benign. There are many microorganisms that we need in our environment.

They basically run a lot of the bio geo, cho, chemical cycles on our own planet. So on balance, they're beneficial. We only sort of noticed them on the broad scale when they're deleterious. Like in the case of the COVID-19. But you can derive some lessons from this, you know, the, um, the fact that we have a new, uh, virus on the scene means, even though it's related to other earth viruses and similar to others in its group of coronaviruses, it's many different properties. And so a lot of the scrambling that's going on now in the medical and research communities is trying to figure out its properties. The way that we, that we do that in real time is orders of magnitude [00:40:00] accelerated compared to what we would have been able to do with, uh, something like this even 20 years ago.

Mat Kaplan: Mm-hmm [affirmative].

Penny Boston: So within mere weeks we had an entire genomic sequence for this RNA type of virus that was propagated around the world. The biggest issue is, you know, we are a world full of people with different traditions, different levels of technical sophistication and different access to communication. And so it's the human response to that, that's been the trickiest part. One of the things that I think is important to communicate is that microorganisms, for the most part, are benign and a-a-absolutely essential to us. And so one of the things I don't want to see is an increase in sort of mindless germaphobia from this. And you know, that could be a natural outgrowth of this. But we are talking about, uh, studying microbial scaled life on another planet. Although, we're mostly looking at bacterial size [00:41:00] things.

And if you look, if you look at a bacteria, you can probably line up maybe 80 or a 100 of them across t-the diameter of one of your hairs. But if I were going to put viruses across the diameter of your hair, I would probably put a thousand, uh, or 2000, right? So they're even more minuscule. So I think we're mostly focusing on bacteria sized organisms. So those are actually much easier to control and work with for the most part than the viruses. Because the viruses are, are tinier than dust specks.

Mat Kaplan: Mm-hmm [affirmative].

Penny Boston: Whereas the bacteria are much chunkier, you know? And so, uh, our, our methods of controlling bacteria and working with them i-in many ways are easier.

Jim Green: Yes. Penny, did a wonderful job, uh, explaining the various aspects of that. Uh, what's critical also to understand is, um, you know, viruses aren't considered alive. They really are cellular parasites. If I, if I were [00:42:00] to describe them in some way and they, they invade the body and, uh, they have some genetic material associated with them but in reality, for them to live and grow, they actually have to co-evolve with a host. And so when we think about bringing material back from Mars that i-is alive, that life has, perhaps, a second Genesis, perhaps is related in some way to us in terms of the fact that it started in a similar environment like Earth but it has a completely different evolutionary track. And so the current thinking is, um, yes, we're going to quarantine those samples. Uh, yes, there'll be in, in what we call Bio level 4 facility, you know, where they handle anthrax and everything else and it will be closely monitored.

But I think, uh, as penny points out, our ability to understand the, the microbiome and virus environment will allow us to those current [00:43:00] tools to interrogate those samples and begin the process of releasing things to the science community. Which will be really important to do because that's where those laboratory equipment, uh, really comes into, into play. Many places a-around the world that will really tease out some of the most spectacular science in terms of really having a deep understanding of that planet, then we, then we can dream up today.

Mat Kaplan: Mm-hmm [affirmative].

Jim Green: So, um, uh, those are all, those are all just right around the corner, you know. And, I'm, I'm hoping also to be, uh, to be around when we start cracking into that next generation.

Mat Kaplan: You and me and Penny, all of us, uh, and everybody watching this program, I am sure.

Jim Green: Now, I was alive and in high school at the time of the lunar landings and it was just, awe inspiring even with the grainy yeti-

Penny Boston: Oh, yeah.

Jim Green: You know, black and white [00:44:00] TV.

Penny Boston: Yeah.

Jim Green: And so today we're gonna be doing it in the high definition. And the colors will be spectacular and the shadows will be long and it will be incredibly eerie but it will be just as inspirational. So everyone, you know, that hasn't seen that original l-lunar landing of any of the Apollo astronauts, have really got a treat in store for them. And that's coming up.

Mat Kaplan: What a great way for us to, to end this wonderful conversation. I wanna thank both of you. Um, there truly were no better people to, uh, be a part of this discussion of Life on Mars and why, we, examples of life down here are so excited about it. Thank you. Uh, Jim Green, NASA Chief Scientist. Thank you Penny Boston of NASA Ames astrobiologist.

Penny Boston: Thank you. Thank you.

Mat Kaplan: And, uh, thanks to all of you for tuning in, for joining us for this a-and to Explore Mars for making it all happen and the great people there who have been helping us out. [00:45:00] Wade, Janet, Chris, uh, Ron Sparkman, uh, Adrianne, uh, and keep looking up there at Mars. We're there and we're going back. Thanks for, again for joining us. Have a great day and stay safe.

Penny Boston: Live long and prosper.

Jim Green: [Laughter]. Live long and prosper. Thanks Mat.

Mat Kaplan: My pleasure.

Penny Boston: Thanks Jim. Thanks Mat.

Jim Green: Take care, Penny.

Mat Kaplan: Time for What's Up on Planetary Radio. Uh, it means that we are joined by the Chief Scientist of the Planetary Society, the Program Manager for LightSail 2 which could be over your head right now.

Bruce Betts: [Laughing]. In fact, it probably is.

Mat Kaplan: [Laughing]. We're everywhere. You can't escape us. Welcome back.

Bruce Betts: Thank you. Good to be back.

Mat Kaplan: I got a message from Allie, uh, saying that her boyfriend, Galen, is an avid listener of Planetary Radio and a member of the Planetary Society. It's his 30th birthday on May 2nd. She's hoping that we could express our condol- N-no, I'm sorry.

Bruce Betts: [Laughing].

Mat Kaplan: Give him a happy birthday [00:46:00] wishes. As you know, Bruce, we can't do that. We're sorry.

Bruce Betts: No, no. We cannot.

Mat Kaplan: Like if we did it for you, we'd have to do it for, let's all say it together, everyone.

Bruce Betts: Everyone.

Mat Kaplan: [Laugh] But you can, here's our birthday gift to you, Galen. You can join in on Thursday, April 30th at 1:00 PM Pacific, 4:00 PM Eastern, 2000 hours UTC. Uh, go to and you will be part of the first Planetary Society Live better known this week, as What's Up Live. Because Bruce and I will be the very first ones to start this new weekly series of live and interactive events from the Planetary Society, And I love it cause you have to do all the heavy lifting.

Bruce Betts: [Laughing]. We'll see. We'll see, Mat.

Mat Kaplan: [Laughing]. It's like a live and interactive WhatsApp, right?

Bruce Betts: Exactly. So we'll, uh, we'll do the random space facts and the trivia and the night sky and uh, [00:47:00] we'll, uh, probably take some trivia in real time and we'll put up some graphics and mostly we'll just be the usual goofballs that we are.

Mat Kaplan: [Sighs]. For all of about 30 minutes. All right.

Bruce Betts: All right. Maybe we should talk about the night sky.

Mat Kaplan: Oh, do we do that?

Bruce Betts: We used to. Uh, so in the night sky we've got, in the evening, Venus now at the brightest, pretty much that it ever is a ridiculous, astronomical, apparent magnitude of -4.7 which is really, really bright. It is also moved into being a crescent. If you look at it through a telescope and it will getting, get more presenty, get dimmer and start dropping lower in the West after sunset in the coming weeks. So check out Venus. In the predawn, we've scoped the three planets hanging out, upper right is bright Jupiter and this is the pre Donnie's.

Bright Jupiter, yellow Saturn and then reddish Mars. As you go [00:48:00] towards your lower left, Mars is separating away. It's, uh, it doesn't want to associate with Jupiter and Saturn anymore. Those gas giants, you know, social stigma.

Mat Kaplan: They're gassy.

Bruce Betts: [Laugh]. We, uh, we were looking for one comment to brighten in may and then we were looking for another but common Atlas. She's breaking up. She's breaking.

Mat Kaplan: [Laughing].

Bruce Betts: Also, seems to be disintegrating. So I wouldn't get your hopes up for a, a bright common than me but we'll keep you posted. Oh wait, it almost is me. Let's move on. [Laugh]. Shall we? Onto this week, in space history in 1989, Magellan was released by the space shuttle and headed off on its way to radar map the surface of Venus.

Mat Kaplan: Oh. And radar, radar is gonna come up again.

Bruce Betts: Oh, cool. Onto. [Singing]. I went down a rabbit hole learning about this. [00:49:00] So I'm sure Mat and many of our listeners are familiar with the astronaut's symbol, the U.S. astronauts and, uh, the lapel pin. Which, uh, looks like three lines headed up to a star going through a halo or an elliptical thing. Well, it turns out at least according to the Manned Spacecraft Center's Roundup from 1964, that those three lines rather than just being kind of a generic shooting star kind of looking thing, actually represent unifying the mercury Gemini and Apollo teams.

Mat Kaplan: Ooh.

Bruce Betts: Is one set of astronauts. I've also seen things that, that don't refer to it that way but it seemed like a pretty good source. But is also interesting and part of this random space fact is that they are awarded silver lapel pins when they graduate from astronaut candidacy to being full blown astronauts and then they get gold ones when they find space.

Mat Kaplan: [00:50:00] That is fascinating. I did not know that. Now really, they ought to add to our lines, one for the space shuttle and maybe now for commercial crew.[Laughing]. Which is about to happen.

Bruce Betts: The circle l-lips represents an orbit, by the way. Not surprisingly sought of an opening here.

Mat Kaplan: Ah, Okay. Not the moon.

Bruce Betts: Not at the, take your pick. I don't know. I'll dive back down the rabbit hole. Let us move on to the trivia contest, shall we?. You, you wild man, had NASA administrator Jim Bridenstine on a couple shows ago. So I asked him what kind of aircraft did NASA administrator Jim Bridenstine fly combat missions off the carrier USS Abraham Lincoln? How'd we do Matt?

Mat Kaplan: One of our few non-space related trivia questions. We have a winner. He's a past winner. But it has been nearly two and a half years since Neil Ashlyn's, uh, name came up in the hopper Neil out of[00:51:00] Davenport, Iowa. I happen to know that he's right about this because it's, it's right there in Jim Bridenstine's official NASA bio. Uh, you can even find it on our website. I'm told it says, uh, Jim flew the E-2C Hawkeye.

Bruce Betts: But wait, we had someone from Iowa win something involving the hot guy?

Mat Kaplan: Yes we did. Isn't that wonderful? [Laughing].

Bruce Betts: That is.

Mat Kaplan: He says, "The strange radome on top of that bad boy or its earlier cousins always fascinated me as a kid." Congratulations Neil. Neil is one of those who we are going to offer an outgoing message or whatever else you want us to record. We just recorded a couple for a couple of the other winners, uh, from Bruce and me for your voicemail system or replace your doorbell chime with it. That'd be fun.

Bruce Betts: Nice.

Mat Kaplan: Earnest Jacobs in the State of New York, which is a state of mind. He says, ready? Hmm. This wasn't on my radar.

Bruce Betts: [Laughing].

Mat Kaplan: From Mark Little in Northern Ireland. Recent winner. As of [00:52:00] 2016, Bridenstine, is a State of Oklahoma record holder in, are you ready for this? Bruce and I, fellow former competitive swimmers. Record holder in the 200 meter long course freestyle relay.

Bruce Betts: Really? Wow.

Mat Kaplan: Yeah. So it says as of 2016. So who knows since then.

Bruce Betts: [Laughing]. I mean, I'd still give them a lot of credit one way or the other.

Mat Kaplan: Martin Joskey, uh, he now spends, that is Jim Bridenstine, now spending a lot of his time in congressional hearings. Might be wishing he was back in combat. [Laughing].

Bruce Betts: [Laughing]. And Maybe.

Mat Kaplan: Finally, a poem from Jean Lewin in Washington. Arising from a flat roost upon Pacific seas enabling sight beyond Horizon's line back to its floating airy. The name of this winged craft for over miles. It can spy like hero from, Mohi, he can last, it bears the name Hawkeye. E2-C was the version [00:53:00] though it was also dubbed with a nickname, not quite as grand. It was called super Fud.

Bruce Betts: Super Fud.

Mat Kaplan: That's it, uh, for this round. We have a cool prize for the next, uh, time around. Yeah, you wanna start that up for us?

Bruce Betts: Back to astronaut pins. Whose silver astronaut lapel pin is on the Moon? Go to

Mat Kaplan: You have until Wednesday, May 6 at 8:00 AM Pacific time to get us this answer. And here's the prize. The great space artist Michelle Rouch. She h-had given us some stuff, donated some work to give away some time ago and somehow this fell, uh, into a, between the cracks apparently or into a crack, I suppose. It's a print of Neil Armstrong that she did, uh, let's see. About six years ago. It apparently, has been a very popular work for me from, from her.

It comes with a certificate of authenticity, uh, from Michelle. [00:54:00] And uh, this will be yours. It's, it's a lovely print. Number 11 of 500 of, uh, Neil, the first man himself. I have it here so it will be easy, relatively easy, to get it out to, uh, our winner.

Bruce Betts: Excellent. All right everybody. Go out there and look up the night sky and think about Marsupial's. Thank you. Good night.

Mat Kaplan: Maybe I should have said it. It m-must have fallen into someone's pouch. Um.

Bruce Betts: [Laughing].

Mat Kaplan: By the way, Michelle's website is www.rouche, that's R. O. U. C. I bet you can just do My fellow, uh, uh, uh, uh, traveler over there is Bruce Betts. He's the Chief Scientist of the Planetary Society. Who joins us every week here for What's Up. And, uh, if you manage to join us in time, you can join us live at for What's Up Live. We'll post it after the fact. For those of you who missed it and you can enjoy it in retrospect as well.

Planetary Radio is produced by the Planetary [00:55:00] Society in Pasadena, California. And is made possible by its members who know that we are the Martians. You can join our Martian Chronicles at Mark Hilverda is our Associate Producer, Josh Doyle composed our theme which is arranged and performed by Peter Schlosser. Be safe everyone. Ad astra.