Planetary Radio: Space Exploration, Astronomy and Science - 20 Years on Mars with Matt Golombek

Episode Date: July 12, 2017

When the Pathfinder lander reached Mars 20 years ago it began a Martian renaissance that has never paused. JPL scientist Matt Golombek was the mission’s Project Scientist. He looks back and to the future of our explorations at the Red Planet.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Matt Gollenbeck and 20 Years on Mars, this week on Planetary Radio. Welcome. I'm Matt Kaplan of the Planetary Society, with more of the human adventure across our solar system and beyond. We just celebrated the 20th anniversary of the Pathfinder lander's arrival on the Red Planet. We're also celebrating the continuous presence of humanity's robots on and above Mars ever since. And I can't think of anyone better to celebrate with than JPL's Matt Golombek, who has been deeply involved in every American mission to Mars over those two decades. Matt will join us in a few minutes.

Bill Nye has the week off as he sets out on tour with his brand new book, Everything All at Once. But we've got Bruce Betts to tell us about the night sky and offer some great prizes in the new space trivia contest. We begin by spending a few minutes with the Planetary Society's Director of Space Policy, Casey Dreyer. Casey, good to get you back on the regular edition of Planetary Radio. It sounds like the nation once again has a National Space Council, sort of. Yes, we do. The executive order has been signed. That means we have a, at least on paper, a group of individuals, heads of various government agencies that all involve space, an as yet

undefined user advisory group of outside experts, probably industry representing space interests, and led by Mike Pence, the Vice President of the United States, as yet to meet to form some sort of coherent space policy for both military and civilian space in the United States. That is the intention. We haven't had one since the early George H.W. Bush administration back in the United States. That is the intention. We haven't had one since the early George H.W. Bush administration back in the late 80s. So it's a step. It's something. And Pence had some pretty flowery things to say when he spoke at Kennedy Space Center the other

day. He certainly did. And he even touched a piece of space hardware that said, don't touch, but don't worry, NASA said it was OK. But, you know, he came and, you know, if I kind of was thinking that I were vice president, I would totally go to all of the NASA centers and give cool speeches and see space hardware. That would be a good perk of the job. I'd, listen, I wouldn't have stopped at touching Orion, I'd have climbed inside. Right, they may have tackled you before you got into that one. But the, it's interesting, I mean, he went down to Kennedy Space Center. He gave a nice speech, and that really shows he didn't have to do that.

Even as the head of the National Space Council, the vice president is always kind of nominally the head of that since back in Nixon and even before days. I think it does show that he has genuine interest in space exploration, and we should appreciate that and be thankful for that because that will make our job in promoting space science and exploration a lot easier here in the next four to eight years. Long ways to go, though. I mean, there are some pretty key members of this group that are still missing. Notably, the NASA administrator does not exist, has not been nominated, nor confirmed, obviously. And the director of the Office of Science and

Technology Policy within the White House has yet to be even nominated. Those are two key positions that we're waiting for. And even again, if they were nominated, let's say tomorrow, as we record this, the U.S. Senate, which confirms these positions, is only in service for about another two and a half weeks before they take a long summer break, the August recess, for about six weeks. And then they come back to some pretty heavy political stuff. And we're not even talking about health care. We're talking about the budget, debt ceilings, debt limits, and all this other kind of attack stuff. Maybe, who knows, there is going to be a very packed schedule, and we may not see an NASA administrator in the office for maybe even towards the end of the year.

Wow, and it's already a record. We do talk about the National Space Council on the latest edition of the Space Policy Edition, and that was posted just last Friday on July 7th. People can find it at planetary.org slash radio. We cover some other great stuff. Casey, what else did we talk about? Well, I posted on Twitter that if you want to cool down from the hot July heat, you can learn all about the ice giants plans that NASA is looking at for explorations of Uranus and Neptune, probably in the 2030s or 2040s. And we look at the policy papers that are happening right now

that are helping to define the efforts that we may see as old men or old women, if you're listening to it, and how that process, how long that process has to take, what they want to do, the type of constraints that they have to be thinking about and working with. It just really shows you just the immense level of planning, preparation, argumentation, and effort that goes into creating even robotic spacecraft, just going out to places like Uranus and Neptune. It was a really fascinating insight into that. Great conversation, too, about ice giants and ocean worlds.

A report about that, too, and a chance to meet your new colleague, Matt Renninger, who is the third member of the space policy team at the Planetary Society. You know what? This is completely objectively, I think it's one of the greatest shows on podcasting right now. Well, we got plenty of listeners who agree with you. Casey, thanks. I hope people will check out that new extended space policy Edition at Planetary.org. Thank you, Matt. That's Casey Dreyer. He's the Director of Space Policy for the Planetary Society.

He and his colleagues are doing good work on behalf of those of us who care about the final frontier in Washington, D.C., where all the big decisions are made. We're going to go on now to talking to a guy who has been a Martian for over 20 years, Matt Golombek, about the 20th anniversary of the landing of Pathfinder on the Red Planet. Matt Golombek was the project scientist for Pathfinder, the Mars lander that brought us back to the Martian surface in 1997. As you'll hear from Matt, this marked the end of a decades-long drought. It also reminded all of us just how exciting a Mars mission is, especially one that included a cute little rover called Sojourner. Pathfinder was more a proof of concept than a science mission, but it still did great science,

and it did blaze a path for the twin Mars exploration rovers and many other efforts to follow. Matt is now the project scientist for Opportunity, the rover that recently completed a stunning 13 Earth years of activity on Mars. But there are many other missions that benefit from Matt's vast experience on the Red Planet, and he has also played a key role in determining landing sites. The senior research scientist received NASA's Exceptional Scientific Achievement Medal and is a fellow of the Geological Society of America. He happily accepted my invitation for a return to Planetary Radio and talked to me via Skype from

his office at the Jet Propulsion Lab. Matt Golombek, welcome back to Planetary Radio and congratulations on helping to be a part of not just the beginning, but throughout 20 years of a continuous human presence at Mars. That is quite an accomplishment. Yeah, I'm amazed it's happened. It's certainly a pleasure to be back, of course. I often talk of myself as being one of the oldest Martians. So a Martian, I'll define as someone who has done nothing but Mars. And I've been doing that now since Pathfinder development. And that was the first Mars mission in the modern era. And I've been doing that now since Pathfinder development. And that was the first Mars mission in the modern era. And I've been doing that continuously. Well, that's 23, 24 years now.

Without regret, I think, right? Do you ever, you know, look up at Jupiter and think, how come I'm not studying gas giants? No, no, no. Mars is way too cool. Not even close. Now, Europa, you know, being a geologist, Europa is kind of cool. But now Mars is it. Yeah, you're a geologist.

So it's nice to go where there are rocks and not just gas. Take us back 20 years to the landing of that spacecraft. Spacecraft and rover on top of it because we we got to talk about Sojourner as well, and what that marked in terms of essentially a return to Mars. Yeah, and I think it's actually, I want to take you back to 25 years before, which is a hiatus of almost 20 years in our exploration of Mars and the failure of Mars Observer, which had happened not that long before. That was supposed to be our return to Mars. And in the Mars science community, I would say a lot of our interpretations were getting pretty

stale because there was no new information. A lot of us who were in the planetary program just felt we needed some way to get back to Mars to revitalize our thought processes about what were going on. All of the analysis was based on 20-year-old Viking data, and people have been picking over that for a really long time. We had to get back there somehow. And we did in style. I mean, it was during that era of better, faster, cheaper, right? Yeah, that's right. Pathfinder was the first or second discovery mission. It was better, faster, cheaper. It was done for less than the movie you didn't see called Waterworld. So we landed a spacecraft and a rover and explored Mars for less than a movie that didn't do very well at the box office. Yeah, I think you got

much better results from the public as well, by far. Did it mark this turnaround in our exploration of Mars and more importantly, our understanding of Mars? Yeah, I think in both cases, the answer to that's yes. I don't think you can consider how could you have a MER if you didn't have a Sojourner? How could you have a Curiosity if you didn't have a MER? And we certainly wouldn't be thinking of a Mars 2020 rover if you didn't have a Curiosity. And so there's a direct lineage from the Pathfinder rover. It was just smaller, but it's basically the same rocker bogey design. There's not really all that much different. You know, we just had a 20-year reunion, and we had an oral history here at jpl and even more so than just

the spacecraft and the hardware yeah the rover is real similar and that stayed common but but the way in which we operate a rover on the surface is fundamentally different from the way you operate an orbiter or even in some ways a fixed lander, because with a fixed lander, nothing, you know, you're in the same place all the time. Rover, each day that you move, you have to make a decision that's based on what happened the previous Sol. And that set up a whole new way of organizing the science team into these science theme groups that would have input. The whole rover can only go in one direction at a time. You can't have the camera guys looking in one direction and sample guys. Everybody's got to be together and organized. And all of that organization of the science team,

the way we operated, the main functioning of how we collected data and put it into sample cache, a lot of the hardware, the operating systems on the central computers, all of that was laid out and begun by Pathfinder. So I would say, you know, without Pathfinder, as a Pathfinder, it's not clear we would have a Mars exploration program. And that's just talking about it from a technical and scientific standpoint. I think if you add in the fact that this was, in my view, without question, the most popular Mars mission ever. I mean, at that time, this is before the Internet was really going. We had front page headlines on every newspaper in america for a week a week there is no other mars mission that's had it for more than a day or two

and this was continuous the whole world was watching us and we had one day we had trouble with the rover being communicated with uh and everyone was interested in what was going to happen. It was, you know, did the rover get off today? What did it do? Oh, my God, is it getting lost? And it brought a whole generation to the surface exploration of a planet in a way that's fundamentally different from a flyby or an orbiter. That excitement, that's what gave us a Mars program. I remember this so well.

And the feeling, particularly from Sojourner, that little rover, it was so charming. It was this little pet that was exploring Mars for us. Yeah, absolutely. And each day you'd look at it, where'd the rover go? What is it doing today? Absolutely. How did you feel when Sojourner was resurrected for the film The Martian? You know, lots of fun, lots of fun. I thought maybe, because I know JPL helped the filmmakers, right, to get it right.

Yeah, yeah. Yeah, that's right. That, as you say, was the beginning that you built on to go to the Mars Exploration Rovers. Opportunity, of course, still very much exploring the surface of Mars. But to stick with Pathfinder for another moment or two, even the MER spacecraft, even the MER rovers, we don't want to forget Spirit, though it is now resting in peace, we hope, had the Mars Reconnaissance Orbiter looking down from above. You didn't have that with Pathfinder, did you? Yeah, that's the main difference is that we had no new information outside of what Viking had collected 20 years before. So if you think about it, you know, I do landing sites as well. We selected a landing site based on Viking images from 20 years before. And the average resolution on Mars from Viking was about 200 meters per pixel. And the engineers are worried about rocks the size of your desk. So it was a whole different world.

MGS had not gotten there yet. There had been no Mars orbiter cameras yet. None of that new information existed. It was from the dark age to... So in a lot of ways, things were tougher. I mean, even our ellipse, we didn't know where Mars was. We didn't know the ephemerides of Mars well enough. There was still a kilometer uncertainty, and that made the ellipse even bigger than... That's the landing ellipse, of course. And that made the ellipse even bigger than that's the landing ellipse, of course.

Absolutely. And it was just a completely different world. And yet now, 20 years, the what Pathfinder started in some ways, I think even the science results were so intriguing and interesting. I mean, it wasn't a it wasn't a science mission. It was a technology demo. I mean, it wasn't a science mission. It was a technology demo. But we had lots of hints that Mars was wetter and warmer and more like the Earth than the moon. And that provided maybe just enough interest, along with, of course, MGS getting there not much later, to really show that Mars was a far more interesting place than we maybe knew or guessed from the Viking data. And that interest helped with the generation of the, as you say, 20 years of continuous presence on Mars. And I would call it the renaissance of Mars science because it wasn't just one mission. It was a whole group of 10 or 12 missions with different kinds of instruments and on the surface and in orbit. And the synergy between

all of those investigations have given us a much, much better view of what Mars is really about. You've mentioned MGS a couple of times, that of course Mars Global Surveyor, that orbiter that served us from orbit over Mars for so many years. What are the most important things that we have learned that have been revealed to us about Mars in this 20 years since Pathfinder? I think the major difference is that from the Viking data, there were hints of valley networks in the ancient Milwaukeean terrain on Mars to suggest that the early environment on Mars may have been wetter. We didn't know how much warmer and how much wetter or how continuous it was. And I would say it was a hint. It wasn't fully accepted that it was wetter. But now, with all of the information we've gotten in the past 20 years, including examples from the surface and from orbit, we have, I would say, unassailable information that rocks were processed into water-bearing minerals on the surface of Mars, that that occurred for significant periods

of times in which water was at least moderately stable on the surface. And thus the suggestion that the very early history of Mars, at about the same time when life got started here on the Earth, that Mars might have been similar. So if water is the common, liquid water is the common denominator for life, as we know it here on Earth, did Mars have a second genesis? Could life have formed anywhere that liquid water was stable, or are we an accident of the highest order? And that's the kind of question that we can ask from a Mars exploration program in a scientific manner. I'd say that's about as compelling as you can get. I also, and you've partially addressed this, but I think of how every spacecraft that has gone to Mars and had success

there has added something to solving this puzzle. You know, Maven, Phoenix, the great European spacecraft like Mars Express, and now, of course, a mom from India. Do you see that as well? Yeah, and that's what I mean by the Renaissance. It wasn't just one spacecraft provided, it was the sum total. And the fact that you could look both on the surface and from orbit with different kinds of instruments looking at different wavelengths, that assemblage is much, much stronger and more powerful than any one of those missions would have been by itself. Let's jump forward to, well, a few years and really to the present, because of course you are the Mars Exploration Rover project scientist. Opportunity, as we said, continues to explore the surface, building on what came before. What is opportunity after now? And what would you say is the beginning of having opportunity land at a location in which

we saw clear evidence for evaporites, sulfate evaporites, that occurred in standing water at the surface of Mars in the late Milwaukee and early Asperian. I don't see any other geologic model that fits that observation. The fact that we've, Spirit saw water processed rock in the Milwaukee and highlands of the Columbia Hills. Those are undeniable cases of groundwater and even surface water being involved in the genesis of those materials on Mars. Undeniable, in my view. Opportunity has since explored the rim of a Milwaukeean crater and found clay minerals that form in neutral pH conditions, kind of like water that you could drink here now. kind of like water that you could drink here now unlike the earlier sulfates which were dominantly acid rich waters almost so acid it's a little more acid than your your car battery

there are things that live in that kind of solutions but they're not a lot of them and we usually think of the earlier neutral ph waters as being more conducive to the genesis of life. So I think we have clear evidence that water was common early on in Mars. And in the earlier period, it was a kind of water that is just fine for life. And so the next question is, you know, were all the elements, were all the things you needed to form life there? Those are kinds of questions that Mars Science Laboratory of Curiosity is beginning to take a crack at. And certainly that Mars 2020 is going to have a major stab at with the return of the samples, eventually we hope, but also the analytic instruments on board. I'm going to come back to that 2020 rover,

but does the work that Opportunity is doing complement the work that Curiosity is doing elsewhere on Mars? Oh, absolutely. I mean, to think about all the surface land area of the Earth, which is about the surface area of Mars, and you only get one rover to land, and you land in Kansas, and you think the whole planet's like Kansas, and that's just not the way it is. There's quite a lot of variety, and the Opportunity rover is the only rover on Mars that is looking at these Milwaukeean rocks. The rocks that Curiosity is looking at are younger and they're fascinating as well, but they're not from that critical period in the Milwaukee when we know that the water was different. We're, of course, hoping that Curiosity gets to drive up the mound and see transitions and stuff. But those are younger materials than this early period when we think if life could have gotten a start,

that would have been the incubator period when it did. JPL Senior Research Scientist and Certified Martian Matt Golombek. We'll be back with much more after the break. This is Planetary Radio. Hey, Planetary Radio listeners, the Planetary Society now has an official online store. We've teamed up with Chop Shop, known for their space mission posters, to bring you space-inspired art and merchandise. You can find exclusive Planetary Society t-shirts, posters, and more. Visit planetly slash space shop to learn more. That's planet dot l y forward slash space shop. planet.ly forward slash space shop.

Hi, I'm Kalisa with the Planetary Society. We've joined with the U.S. National Park Service to make sure everyone is ready for the 2017 North American Total Solar Eclipse. Together, we've created the new Junior Ranger Eclipse Explorer Activity Book. It helps kids learn about the science, history, and fun of eclipses. Call your nearest national park and ask if they have the Eclipse Explorer Book, or you can download it from mps.gov slash kids or at planetary.org slash eclipse. Welcome back to Planetary Radio. I'm Matt Kaplan. I seriously doubt that there is a scientist who has furthered our exploration of Mars more than JPL's Matt Golombak. Name the mission, and he has probably had a hand in it and helped lead

the process of choosing its landing site, if it was a lander or rover. He is the Mars Exploration Rover Project Scientist, overseeing the science conducted by that Mars veteran, Opportunity. overseeing the science conducted by that Mars veteran, Opportunity. What is ahead for Opportunity if it continues to do this utterly incredible job of outliving its warranty? We're so far beyond now. We've had several additional hardware difficulties. The other front wheel is no longer turning, you know, steering, but they still rotate. We've had good luck since that occurred with steering the rover and continuing our traverse. Just driving backwards now, right? Driving backwards, and those wheels turn just fine, and we also do skid turning. It's

good skid steering like a tank, and that's working okay as well so so we're still hopeful that even though there's lots of things that aren't as good as when it was brand new it's still capable of doing some fundamental exploration today in fact we just started our plunge into perseverance valley which is we think a water worn valley on the edge of Endeavour Crater. And we're getting ready for the conjunction, which is coming up in a couple of weeks, when Mars will be on the opposite side of the sun from the Earth. We'll be out of communication for several weeks at least. And then a winter is coming as well for opportunity.

And then a winter is coming as well for opportunity. And we need to make sure that which are north-facing areas that we can park on from day to day and continue to scoot between them and continue our exploration. And our hope is to figure out whether this was rainwater, water from a lake that breached the rim and went down the valley? Or could this have been like a mud flow or some saturated lithic with a lot of debris in it that carved this valley and tried to distinguish between the formation mechanisms? You reminded me of something, not to be too irreverent, I hope, but I wonder if you and the team ever thank the gods of Mars that there are dust devils on that planet to clean off opportunity now and then. Yeah. And remember, during the development of MER, because of the fallout of dust on the Pathfinder panels, which were measured for about 90 sols, we noticed at the very end there was this pretty continuous rise of the dust on the panels. And at the end, it almost looked like it leveled off, but we didn't have enough data at the end

to know what was going on. And so the projections for MER with the size of the panels is that by Sol 85 or so, there wouldn't be enough power to move the rover. And that was the 90 Sol mission. I remember back to our operating those rovers in Mars time in the early part of the mission, it was like we had a sniper trained on us. And we had to do whatever we could do to get as much as we could. And then we noticed that there were these dust cleaning events. And we think they're probably dust devils. There could be other factors involved as well that are cleaning the panels. And it's clear that's occurring over and over and over.

And that's led to the longevity of our spacecraft. So they're pretty fortunate. It's a great part of the story. So, of course, Curiosity doesn't have that problem. It's got those radio thermal generators, radio isotope thermal generators. Same will be true with the 2020 rover. Technology marches on. But beware now, because of the half-life, they will also decrease in power with time.

Yeah. Yeah, yeah. Such is the nature of plutonium, right? I'm also thinking of another improvement, though, a genuine technological improvement, and that is to go back to your mention of that big ellipse you had to deal with for Pathfinder. Those ellipses keep shrinking, don't they? Yeah, they're dramatically smaller. So I think at the end, I think we were like 20 by 15, 20 at the final ending point there when we were tracking it coming in. With aerial maneuvering, Curiosity's gotten it down to even smaller. Mars 2020 is using a new shoot deploy algorithm that shrinks it down to 12 by 8, 20 by 12, very, very small.

So you can put them in lots more interesting places. using a technology called terrain relative navigation, where the spacecraft takes an image, it matches it to an image that we've created from orbit. It then knows exactly where it is. And we've already defined as well the areas that have rocks that could be hazardous for landing or steep slopes or large bed forms that you might not be able to drive out of, and it can steer away from those. And thus it can land in much more, I'll say, hazardous areas than you could where you didn't have any control as to where you would actually wind up in the ellipse. All of this very reassuring and must be very nice for the scientists like yourself to consider. How is this process of choosing where 2020 will land going? I ask because, of course, you are the Mars Exploration Program Landing Site Scientist at JPL.

Yeah, and typically site selection is a three- to five-year process that occurs during the development of the spacecraft. It has to occur then because no matter what, the spacecraft changes during development. It's not exactly the same. And you learn a lot more about what it can handle and what it can't during the development process. So we take a slow measured approach. So we take a slow measured approach and we go out and we ask the entire science community where you would land a spacecraft with the science objectives of this type and what it about eight sites to three sites that look the most promising for landing 2020. And it was based on, are there rocks that could have contained a habitable environment? Could we be sequestering the materials and showing what those materials are in that environment

so we know what that environment was? And is this a good place for a potential sample return since we're also collecting samples and wanting to return those? And those three sites are Northeast Sirtis, Jezero, and the Columbia Hills. And we'll be studying those for probably another year or so to when we have another workshop to try to narrow it down further. So are there advocates for each one of these, all of them talking about why? Pick mine, pick my site. Yeah, that's right. But what makes these workshops so exciting is they're really at the forefront of what you can infer and understand about a surface and the geologic materials that are there from orbit.

You're going from orbit and you're trying to get at what the surface is like. I think we've done a pretty good job over the years of determining the safety of a landing site, how many rocks, what are the slopes. Those are things that we've figured out how to measure. But figuring out what rocks are there and the provenance of those rocks and how they formed, that's trickier and much more difficult to do from orbit. And what's so fun about the workshops is everybody comes with their best data and there's these big discussions about how well do you know that and what's that based on? And in ways that don't happen at the usual science conferences where you only get one or two questions and then you're off the stage. So we have long discussion periods with both advocates as well as impartial observers that are looking at it.

And in fact, everybody who's there and everybody gets to vote on what their preference is. I mean, how American is that? American. And it just sounds like exciting science. It just sounds like exciting science to be part of. It really is. It's among the, it's a really just a fun way to understand some of the most compelling aspects of Mars science in a super detailed way. Whatever site ends up being the chosen one for the 2020 rover, we're still looking again at that seven minutes of terror, right? Yeah, and there's nothing you can do about it. That's how long it takes to go through the atmosphere on Mars when you're traveling at several kilometers per second between here and Mars. Yeah, that's right. What else are we looking forward to? Are you part of the InSight mission? That's right. I'm a co-investigator and the landing site lead and

geology lead for InSight. That will be launching in 2018, so less than a year from now, in about May of, Cinco de Mayo of 2018. That will be the first Mars mission to launch from Vandenberg, as opposed to Cape Canaveral. That mission is a, it's kind of, it's like taking the temperature and activity level of Mars. It's carrying a seismometer, extremely sensitive broadband seismometer. It carries a probe that will measure the heat flow of Mars. And it has a precision tracking station that should be able to, between the three of those together, we should be able to understand the interior structure of Mars. And this has been an area that's been wildly overlooked in our Mars exploration program as we're really focused on the Milwaukee. But you have to understand the whole planet together to make real strides in our

exploration. And this will be the first mission that's really devoted to the internal structure. We should be able to determine whether Mars has, we think it has a metallic core. Does it have a liquid metallic core? Is there a solid core inside of that like we have on Earth? What is the structure of the mantle? What are the main phases that make up the mantle? And it will give us a 1D profile, the thickness of the crust, the mantle, and the core, as well as the seismic activity, the tectonic activity that's occurring on Mars today, as well as the impact rate. And those will form then effectively our arrays that will sample the rest of the planet

in terms of the interior structure. So there's another piece of the puzzle called Mars. Looking beyond 2020, we at the Planetary Society are concerned and talking to people in Washington about that because we don't see as much activity, missions being laid out beyond 2020. Even, you know, missions like Orbiter to replace MRO, that's going to allow us to keep talking at the rate we'd like to, to what's already there, Curiosity, if it's still working, Opportunity 2, but also the 2020 rover. Are you concerned as you look out beyond

2020? Well, there's always the planning horizon. And, you know, part of our problem is we're successful. Our missions seem to last much longer. And so there's operating budgets that are required to keep those missions operating. And those come out of the same Mars exploration program pie, if you will. Yes, we are all concerned. We all recognize that MRO is becoming an aging spacecraft. It provides absolutely fundamental information for landing site selection. Having those high-rise images at some meter per pixel are absolutely critical for determining the hazards and kinds of materials. And having a relay there for the future missions to communicate. All of our communications now goes from the surface to an orbiter and the orbiter to Earth.

Almost nothing is sent direct to Earth as we did in Pathfinder days. Yep. No choice. so we need a replacement we need a mars next orbiter and i guess my view is that if we go with 2020 and we find compelling samples that we have collected that will hopefully provide the impetus for completing the sample return, portions of a full sample return to get those samples back from Mars. So I'm an optimist, so I'm hopeful. I'll just follow that up with one other sort of personal question. If you were the NASA administrator and were handed a lot of money for another mission to Mars, let's assume that there is another orbiter, an MRO replacement with communications technology and a big telescope like HiRISE. What mission would you most like to see going to Mars next

as a follow-on to what's already happened? In a sense, the Mars science community has made a statement that the return of carefully collected suite of samples from the surface of Mars would provide the biggest advance in our knowledge. And I don't disagree with that. The difficulty is getting those samples back from Mars and how many additional missions and the cost of those missions to do it. So the Mars 2020 rover will collect and cache those samples. You now need a mission to go and get those samples and put them into a sample return canister and launch them from the surface of Mars, presumably into orbit, the current kind of scenarios. Then you need a Neville mission that would go and collect that

sample canister from Mars and bring it back to the Earth. And then you need a sample collection facility on Earth that rivals the Center of Disease Control contamination facility, that would cost equally as much as any of those missions to ensure that those materials were kept separate from the Earth. So those are all big ticket items. And how you then begin those steps towards returning those samples are really the difficult part of our planning exercises. Sample return, I guess if it was easy, everybody would have already done it. Yeah, and we would have done it a bunch of times too. I hope that that is still in our future as we continue to explore the red planet.

as we continue to explore the red planet. Thank you for your long career on that world and on this one. And I hope there are many more successes ahead and that we can talk to you again as we continue the exploration. I look forward to it. Matt Gollenbeck, we've been talking with him in his office at the Jet Propulsion Laboratory, where he has been for so many years. Currently is the MER Project Scientist, that's Mars Exploration Rover Project Scientist. Previously, of course, as the Pathfinder Project

Scientist, but with many other jobs and research efforts underway, he continues to be one of the leaders of our efforts to choose a landing site on Mars for the next rover that we'll visit there, the 2020 rover, which still doesn't have a nicer name. I hope there'll be a nice contest for that. I'm sure there will. We're used to offering contests. We're going to have another one right now, another space trivia contest, when we go to Bruce Betts for this week's edition of What's Up. week's edition of What's Up. Time for What's Up on Planetary Radio.

Bruce Betts is the Director of Science and Technology for the Planetary Society, and he's back with more about the night sky and other good stuff and another Planetary Radio t-shirt to give away. The new design, which one of my brothers now has. I still design, which one of my brothers now has. I still don't have one.

It's really hard to feel sorry for you. I don't know how this happened. But we do like your brothers better than we like you. So that could have something to do with it. Everybody does. It's just not fair. And he became a member and was able to pick up a shirt. But I'm still looking forward to getting mine anyway.

You don't have one yet, do you? No, but I'm not complaining, am I? No more complaints. Tell me about the sky. Well, get up earlier, stay up late, because Venus is just looking lovely in the eastern sky in the pre-dawn, and it's hanging out for the next week or so. It's actually moving past Aldebaran, the bright star in Taurus. So that's something to look for. And on the morning of the 20th of July, the crescent moon will be hanging out near Venus looking quite lovely.

And, of course, in the evening sky, we've still got Jupiter bright in the west in the early evening and Saturn up in the south in the early evening. And both of them uh I'm sorry then up later in the evening I'm so excited about Venus and Aldebaran and the moon I just kind of petered out and t-shirts t-shirts all right we move on to this week in space history 1965 1965, Mariner 4 did the first successful flyby of Mars. 50 years later, to the week anyway, New Horizons in 2015 this week flew past Pluto. And they look remarkably the same. No, not true. They're both reddish.

Yeah, that's true. They both have varied terrains. You can make analogies, but they're made of very different stuff on the surface. Yeah, great milestones. Are you taking requests for random space fact impressions? Yes, as long as people are okay with how terrible my impressions are. It's unfortunate because my son, particularly Daniel, is very talented at impersonations. And I'm not, but let's have fun with it.

What do you got? Well, you can always bring Daniel back in on one of these. But since he's not around right now, here is a request from Gabriel Thelen in Australia, one of our Down Under fans. There are a lot of them. He says, has Bruce done an Emperor Palpatine random space fact impression? I can guarantee I have not. I can try. I mean, what's the worst that I do?

I butcher, you know, the evil dude. So I suppose that's okay. Go for it. All right. Young fool, only now, at the end, do you understand the power of random space fact. Well done, well done. I can feel the star system slipping through my fingers as you speak. It's channeling the power of the dark side.

Goodness knows I've got plenty of it. There you go, Gabriel. He might be a better director of science and technology and astronomer than he is an impressionist, but you can't complain about that. I don't know how to answer that. So I'll just give you the fact. This I find fascinating. Pluto's minimum distance from Uranus at 11 AU, 11 astronomical units,

distance from Uranus at 11 AU, 11 astronomical units, is actually less than its minimum distance that it ever has to Neptune at over 17 AU. That's because Pluto is in a two to three orbital resonance with Neptune. In other words, Pluto orbits twice for every three orbits of Neptune. One of the implications is that the objects never come that close to each other. That is a truly great random space fact. I'll file it under truly great ones. Yeah, me too. All right, on to the contest. All right, I asked you,

in what year was the supernova observed that formed the Crab Nebula, which you can still see even in relatively small telescopes now? How'd we do? What I loved about this one is how many people said they didn't need to look it up. What an audience. Jeff Belback. Jeff Belback, I think a first time entry, said that the supernova that would form eventually the Crab Nebula was recorded by Chinese astronomers in, drum roll please, 1054. 1054, is that right?

That is correct. Jeff, congrats. Nice work on your first outing. And if it's not, nice work anyway. You are going to receive that brand new Chop Shop Design planetary radio T-shirt along with a 200-point itelescope.net astronomy account to do astronomy from home, but using telescopes all over the world on that network that belongs to iTelescope.

So have fun doing that. A different Gabriel, actually, Gabe Eggers in Atlanta, Georgia. He said, fun fact, the Chinese called supernovae guest stars due to their bright and temporary nature. And this evening's guest star will form the Crab Nebula. You stand back, please. Ilya Schwartz. We hear from him a lot in Columbia, Maryland.

It was observed later by English astronomer John Bevis in 1731. The nebula was the first astronomical object identified with historical supernova explosion, he says. There's also some evidence, according to Ilya, that it was seen in the Middle East, in Baghdad. There was a report made, actually it was a copy of a report that didn't appear until the 13th century, copy of a report that didn't appear until the 13th century, but apparently it was observed back in 1054 from there as well. Then, just to throw this in, Joseph Ladd, with this comment for us, thanks for continuing to spread the word. Whenever someone asks me about my planetary radio shirt, I beam with joy and tell them of all the great things you do. So happy I can be part of it.

Did you write that one? I missed it. No, didn't I say Joseph Ladd in El Portal, California? Not one of my pseudonyms. One of your brothers with a planter radio t-shirt? No, no, they're all named Kaplan. All right, here's your trivia question for next time. What other kind of ice forms what appeared to be snow-capped peaks on the top of water ice mountains on Pluto. What's the ice that was found to be covering some of the peaks of the water ice mountains on Pluto?

Go to planetary.org slash radio contest. Good one. You got until Wednesday, July 19 at 8 a.m. Pacific time to get us the answer. Win yourself a Planetary Radio t-shirt, the new design from Chop Shop, the Planetary Society Chop Shop store. You can check that out online, 200.9telescope.net account, and your very own set of Bill Nye and Planetary Society eclipse glasses. of Bill Nye and Planetary Society eclipse glasses. They're the cardboard kind, but they have the certified plastic that you can look through safely when the eclipse comes on August 21st, the Great American Eclipse.

Excellent. Go out there, look up at the night sky, and think about what you would do with force lightning. You know, that stuff that shoots out of the emperor's hands. What would you do with it? Thank you, and good night. I'd make toast. He's Bruce Betts, the Director of Science and Technology for the Planetary Society,

who joins us every week here for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by its members, who are pretty much all Martians. Danielle Gunn is our associate producer. Josh Doyle composed our theme, which was arranged and performed by Peter Schlosser. I'm Matt Kaplan. Clear skies.