Planetary Radio: Space Exploration, Astronomy and Science - All Shook Up: The InSight Mission to Mars

Episode Date: May 2, 2018

No mission to Mars has done what InSight will do.  The lander’s spectacularly sensitive instruments will use the Red Planet’s heat and marsquakes to reveal its deep interior while also revealing secrets of other rocky worlds like our own Earth.  Principal Investigator Bruce Banerdt came to Planetary Society headquarters barely a week before launch for a long and fascinating conversation. Planetary Society CEO Bill Nye says the European Space Agency’s Gaia spacecraft has mapped our galaxy as never before.  Bruce Betts will help us explore a bit of the Milky Way in this week’s What’s Up segment. Learn more about this week’s topics and see images here: http://www.planetary.org/multimedia/planetary-radio/show/2018/0502-bruce-banerdt-insight.htmlLearn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Shaking things up on Mars, this week on Planetary Radio. Welcome, I'm Matt Kaplan of the Planetary Society, with more of a human adventure across our solar system and beyond. You may think InSight is a mission to the Red Planet. Bruce Bannert says it's really about understanding our own world. Join me for an in-depth, pun intended, conversation with the leader of the next spacecraft heading for Mars. I don't think you'll learn more about this mission of discovery anywhere else. But there's more to learn about the night sky from Bruce Betts in this week's What's Up segment.

And we have just learned more about the entire Milky Way galaxy. Much more, according to Planetary Society CEO Bill Nye. Bill, big news from the European Space Agency. We know our galaxy a lot better than apparently we did not long ago. Yes, the Gaia spacecraft, European Space Agency spacecraft, has just completed another round of survey, however that expression is, another survey, finding billions more stars.

And not just finding them, but finding them in three dimensions. So knowing their distance relative to other stars and their motions relative to other stars. It's just one more way to know the galaxy, to know the cosmos and our place within it. Among the many things I found cool about this, it's the Hertzsprung-Russell diagram. I learned that. Intro to astronomy. Yes, brightness and size and age. Anyway, this makes it much more thorough.

There's more data on the graph. They've mapped some asteroids. So not only these distant, distant stars, but these, in cosmic sense, nearby objects, things that would only take you, you know, five hours at the speed of light to get to. So it's really amazing. And so more power to them. It's the European Space Agency's project called Gaia. Space exploration really does bring out the best in us. These scientists in Europe have developed spacecraft that will produce data that will be shared worldwide. And do you know what we're going to learn from this? Nobody knows, Matt.

But it will give us more insight, I hope. What I see, here's the thing. What I'd like found in my lifetime is life on another world. If there is an asteroid with our name on it that's going to hit the earth, I'd like to figure out where it is and give us a chance to deflect it. And then I would like to know what dark matter and dark energy is, are, what. By knowing more about the positions of stars in the galaxy and their relative motions, you're going to learn something about this mysterious force and a mysterious source of energy that we don't know yet. One more thing that goes on in the background. That's kind of

a cosmic radiation pun. It's one more thing that goes on in astronomy that will have a profound effect on us. It's cool. It's exciting. Thank you, Matt. Speaking of profound effects, obviously space exploration has had a profound effect on you because you've put your money where your mouth is. Oh, yes. On the matching gift campaign. Yeah.

Could you tell us about this so-called Reach Higher campaign that the Planetary Society has underway right now? There's a member of our board who's closely connected with something called the Hudson Foundation, and they have offered matching gifts. That is to say if you send money—oh, not send money, excuse me. to say if you send money, not send money, excuse me, if you engage in our opportunity to participate in our culture of philanthropy, they will match the gift and so will I. So Matt, between you and me, I've been working on television for a long time. The last couple of years have been good. I wrote some New York Times bestselling books. So I also came in on the same program at half the price, frankly. I believe in the organization, the Planetary Society. I'm a charter member. We'd like you

to join us in supporting our work. So, you know, it's an exciting time. We're going to launch LightSail 2 later this year. We have a Planetary Science Caucus in the United States Congress, where we advance planetary science in the legislation and governance of the world's largest space agency and how it cooperates with other space agencies. Consider a listener to Planetary Radio and participating in our cultural philanthropy by giving us some money and I and the Hudson Foundation will match your gift. It's an exciting time. It's planetary.org slash reach higher, both words, but as one word. And the deal is that the first 50,000 that we receive from people will be matched by both you and the Hudson Foundation.

$50,000. So you're really tripling that money. We're here for you, man. And then the next $50,000, it's just doubled, only doubled by the Hudson Foundation. So here's the thing about philanthropy and donations. There's a big human nature component to it. So if you guys are willing to donate money i am willing to donate money if you all are willing to donate money the hudson foundation is willing to donate

money so thank you for your support we're just out here trying to change the world people do you mind saying the name of that board member who is basically charlie hooser so when you spend time with Wally, if you spend 20 seconds, you will find out that he loves space exploration. He's a radiologist in the Texas University system. Everybody loves him. They bring him back for all these guest lectures. And he is a space enthusiast, man. So Wally and I are here for you. If you donate money, we are going to donate money.

All right. One more time. Planetary.org slash reachhigher. Well, it's on your homepage, planetary.org. Just go to reachhigher. Thank you, Bill. Thank you, Matt. We have roved the surface of Mars, we've dug into its Arctic, we have tasted its sky,

and we've mapped it better than any world other than our own. But we know very little about what's going on deep inside. What secrets are hidden away hundreds, thousands of kilometers beneath the sands and rocks? Can Mars tell us about the origin and evolution of our own planet? Bruce Banner thinks so. He is principal investigator for the InSight mission and a principal research scientist at the Jet Propulsion Laboratory. Yep, it's an acronym. Interior Exploration Using Seismic Investigations,

Geodesy, and Heat Transport. Nothing like it has ever visited the red planet. It was my pleasure to welcome Bruce Bannert on his first visit to the headquarters of the Planetary Society a few days ago. It's my pleasure to be here, and you got me kind of at the sweet spot. Any time later than this, and I would probably not even notice your inquiry. I am incredibly grateful and somewhat surprised, though pleased, that a week out, the PI of the mission going to Mars in seven days had time to join us here. But I'm really glad you were able to.

Part of my job and actually part of my passion is actually sharing this stuff. So a lot of the time between now and launch, I'm not going to actually spend in front of microphones like this, just talking to reporters, talking to people and spreading the word. Well, you know how important we feel that is around here. So we're happy to give you yet another audience. Now, by the time most of our listeners or many of our listeners hear this, fingers crossed, Insight will be on its way to Mars, right? Whoosh, yes, absolutely. A six-month trip, roughly? Yeah, about six and a half months if we go off on the first launch opportunity. How long is the window?

The launch window is actually two hours. We call the daily interval a window. So we have two hours per day for five weeks going all the way to, I think, June 8th. So plenty of time to get it right. I'm going to come back later to where you're launching from, because as a native Californian, I'm pretty proud. But let's talk more about where you're going to, first of all. Where on Mars are we headed this time? We're going to a spot in western Elysian Planitia, and it's just a few degrees north of the equator of Mars, and actually only about 450, 500 kilometers north of Curiosity, which is in Gale Crater.

And this is a nice, flat, what my geologist friends call boring spot on Mars. And we actually picked it not because it was a scientifically interesting place to go, although I think just about any place on Mars is scientifically interesting, but because the point of this mission is not to study the environment of any particular place on Mars, but to make the first detailed map of the inside of the planet from the surface through the crust all the way down through the mantle to the very core of the planet and understand what the structure of the inside of the planet is. And I tell people that if you're going to study the core of the planet,

anywhere you stand, the core is right under you. So it doesn't really matter where you go as far as the science of the mission goes. It's always pointing down. Absolutely. So if you find a little puddle of microorganisms wells up, you don't really care. No, not really. I'll pass that off to some of my astrobiology friends. Tell curiosities, needs to take a longer hike. Before we go on, one of the people on your team, Matt Golombek, maybe Mr. Where to Go on Mars guy.

Absolutely, yes. He's the Mars landing site guy. That's how he calls himself. And has been a frequent guest on our radio show. I'm going to go out on a limb. And we've reported frequently as well on this program about MAVEN, that orbiter, which has told us so much about what's above the surface of Mars. In that sense, is it appropriate to think of InSight as sort of doing for our knowledge of Mars, looking down what MAVEN has done for what's above? That's actually right on the nose. I mean, before MAVEN, we'd sent, I don't know,

probably dozens of missions to Mars to study the geology, to study the rock composition of the surface, do spectroscopy, do mineralogy, and trying to understand the environment today and in the past. Everything above that and below that, I think, got kind of short shrift in a way, just because, you know, we were so successful with the geology and we had these amazing robot geologists that could tell us so much about the planet. With MAVEN, you know, I think we finally were able to sort of extend our view sort of outward from the planet and understand, you know, the upper atmosphere

and its interaction with the solar wind and so forth, which left what I consider to be the last big gaping hole in our fundamental knowledge of Mars, which is the deep interior of the planet, which is volumetrically, we're talking about, you know, 99.99% of the planet, you know, everything below the top few centimeters or maybe a few kilometers if you count some of the sounding radar from some of the orbiters. We have a fuzzy idea. We know that there's a core in Mars. We know it has a crust. We have ideas about roughly how big these things are, and we have theories about what they're made out of.

But there's nothing like a measurement to really push the science forward on something like that. And we will get measurements of these quantities for the very first time with InSight. So this is geophysics as opposed to geology? Exactly. And geophysics is taking the methods of physics, of using physical processes to extend our vision in places where we can't see or touch. If you want to go and figure out what's inside a planet, you can say, well, let's just drill down and see what's down there. And you get down about 12 or 15 miles. I'm not sure what the record is right now in the deep hole up in the Arctic of Russia, but 12 or 15 miles doesn't get you very close to a core that's 6,000 kilometers below your feet. So

you have to use other methods, you know, how the materials down there affect physical processes that you can detect at the surface. So you can use gravity measurements. You can use magnetic measurements. Or you can use what we're going to use, which are seismic measurements, which turns out to be sort of the gold standard for probing deep into a planet. I want to come back to not just your seismic experiment, but all three of the main instruments that you've got on this spacecraft. But first, and a lot of this is on the website, which we will put up a link to on the show page at planetary.org slash radio, as always. And it's a really good site. It has lots of great explanations of everything that's going on in the mission, very easily understood.

It talks about two main science objectives, which you've talked a little bit around now, but what are those? science objectives, which you've talked a little bit around now, but what are those? Well, the main objective is, our overall goal, in fact, is actually to understand the formation of rocky planets, what we call terrestrial planets, planets like the Earth that are made of rocks rather than the gas giants or the ice giants of the outer solar system, which, by the way, Juno is doing an amazing job of doing kind of the same kind of thing. Insight is after, but for Jupiter rather than for Mars. And the reason why we can do that is because Mars is kind of a special place. We call it the Goldilocks planet because it's not too big, it's not too small. It's just right for

looking at the processes that occurred at the birth of the planets in the early solar system. What happens when a planet accretes from the solar nebula, it heats up and starts to melt, and then the materials separate. The heavy material, the metallic iron and nickel, kind of rain down and accumulate at the center of the planet in the core. And then as the silicate, the rock component, starts to crystallize, the light elements, light minerals rather, tend to float towards the top,

and the heavier ones sink towards the bottom. And you end up with a stratified planet with a crust made out of what we call low-pressure phase minerals and rocks, a crust made out of what we call low-pressure phase minerals and rocks, and the mantle made up of more dense, higher-pressure phases. But that process gets hijacked by dynamics, by stirring up of this melted material. So if it was still, everything would settle out, and you could figure out exactly what a planet would look like just from our laboratory experiments. But meanwhile, this thing is convecting.

It's churning around. Things are getting mixed back in. Some things that were solid, as it gets cooler but higher pressures, they can actually remelt and then crystallize as something else. And so it's a really complex process that we can't really model completely in the laboratory. And so we'd like to understand that process, which occurs just in the first few tens of millions of years of the planet's life, which is just a couple ticks in the clock out of the four and a half billion year lifetime of a planet. Very early in the planet's history, this whole structure, crust, mantle, and core is set up. And then that kind of determines where the planet's going to go along its path forward. So on the Earth, that path included

plate tectonics, which has had the effect of erasing all the evidence of those processes. So all the crust on the Earth has been recycled back into the mantle multiple times probably. crust on the Earth has been recycled back into the mantle multiple times probably. And so none of the original crust is left on the Earth. And we've had continuous remelting, both from volcanism and also from the formation of basalts at mid-ocean ridges and so forth. And the mantle has been completely mixed over and over again by convection. And so the fingerprints of those processes really don't exist on the Earth today or are very faint. So we went to the moon, and we actually took seismometers to the moon and did a lot of studies of the interior of the moon.

We brought back samples, did isotopic measurements, and we learned a lot about this differentiation process, this process of separation of the materials. But that is not very applicable to the Earth because on the Moon, if you figure out what the pressure and the temperature is at the very center of the Moon, that's only about maybe 200 miles deep into the Earth, which doesn't cover much of the territory. Furthermore, all these processes are really dependent on pressure and temperature. And so you have another several thousand kilometers of area, which is undergoing processes that we just never see happen on the moon because it's just not big enough.

Mars is big enough to have undergone most of those processes. It's big enough to have pressures and temperatures that go all the way through the upper mantle of the Earth and into the lower mantle. And so it underwent the kinds of processes that the Earth went through, but it stopped. It stopped once the structure was set up. And in terms of the interior structure, very little has happened since then. We have several lines of evidence that lead us to that conclusion. So we think that Mars is really a window into the distant past, into the very earliest sort of birth throes and evolution of the planet. And we should be able to take that information, which is contained in some fairly basic numbers, like the average thickness of the crust, the size of the core, whether the crust is a single composition or whether it has maybe lighter rocks on the top

and more dense rocks below and some kind of stratification. And then if there's some kind of stratification or layering in the mantle, these are all clues as to how these processes went on, layering in the mantle, these are all clues as to how these processes went on, as well as things like the composition of the core. If you have iron that rains very quickly down to the core, it's going to be relatively pure because it doesn't have time to absorb and dissolve lighter elements in this molten metal droplets. If it takes a long time to percolate down there, it probably absorbed more of these lighter elements and the core itself is going to be less dense, which has implications.

Implications keep on going. I could talk for an hour just pulling one of these threads. But if you have, say, a few percent to maybe 10 or 15% sulfur in the core, that lowers its melting temperature. So whereas today, a pure iron core would almost certainly be solid, completely solidified, whereas we know from orbital measurements that there is some liquid layer, at least in the outer core, and that means that its melting temperature must have been lowered by adding some lighter element mixture to it. So Mars, even though you hope to look back, what, four and a half billion years, it's maybe even today not quite as dead as we might once have thought.

I mean, you said that there's thinking that there may still be some molten iron down there. Oh, absolutely. And, you know, Mars, you know, the basic structure has been pretty static since its early history. But, you know, we can look at the geology of Mars. I mean, the Mars rovers have shown that there's been a very, you know, active geological history on Mars. And we can see lava flows from orbit, which have no craters on them, which means they're less than a few million years old. So there is active volcanism in the recent past. There's no reason to think that it's completely dead even today. In fact,

we're counting on the fact that Mars isn't dead because one of our main tools we have that we're planning to use with InSight are the seismic waves that are generated by Mars quakes. And so we need to have forces in the Martian crust, which are continuing to produce motion along faults. And we're pretty confident that that's happening, again, through several lines of evidence. It seems like so much to be hoping to learn from one little spacecraft on a planet with three major instruments. But I guess this is all based on good science that has been done here on Earth, right? Yes. I mean, all the techniques that we're using on inside are ones that are tried and true, well-tested on the Earth. Maybe 90% of what we know about the inside of the

Earth has come from seismology, from analyzing earthquake waves that have traveled through the Earth. They're like little trains that run through the earth and pick up baggage along the way, you know, as they go through the various different rocks, you know, little souvenirs. And once they come back up to the surface, we look at those wiggles and put them through our mathematical analysis techniques and try to pull all that information out that those waves have picked up as they go through the planet. Let's talk about this instrument, probably the one that has attracted the most attention, SISE, the Seismic Experiment for Interior Structure. Does that work in French as well?

No, actually, they have to kind of anglicize even the pronunciation, but they're very gracious about that. And the reason, of course, that I bring up French is because this is basically a French instrument. That's right. The French Space Agency has funded most of this instrument, and they have overseen the construction. It's actually built by a consortium. I think France is responsible for north of 80% of the instrument, but they have contributions from Switzerland, instrument, but they have contributions from Switzerland, from the UK, from Germany, and from the US. JPL has built some key components of the instrument as well. And so it's a very international instrument, but the French have definitely done the lion's share of the work on it.

Yeah, like most planetary science missions nowadays, it's a global mission, basically. You mentioned JPL. I don't want to let this go by as we talk about the size instrument without saying, I mean, the major hiccup, I suppose, in developing the spacecraft was this problem with this vacuum chamber that's part of the size instrument. Yeah, that's right. The seismometer, it's, well, I have to say it was a very challenging development. I mean, we're building an instrument and I don't think people, when they think about earthquake research, you know, they think about, especially here in Southern California, everybody knows what an earthquake feels like. You know, it moves things around. You feel the building swaying. You know, you think a seismometer, that must be, you know, a reasonable instrument.

But most of the science that's done with seismology is done with earthquakes that happened on the other side of the world. In California, we pick up earthquakes that happen in Japan, in the Middle East, in the middle of the oceans. By the time those waves get here, they are extremely small vibrations. And not only do you not notice them, it's very difficult to measure them. So the seismometer that we're sending to Mars actually has, we have a specification on the sensitivity of it. And that specification is to be sensitive to motions that are equivalent to

about half the radius of a hydrogen atom. Which is just extraordinary. And I tell people, that's not diameter, that's radius. That's small. And so these are the motions that we're trying to pick up on Mars. And it's, you know, it's not crazy stuff to do because the standard research instruments on the Earth, you know, do this routinely. Of course, they usually do that in a temperature pressure controlled room, you know, that's buried to get away from the noise and stuff like that. We have to do it in the dirt on Mars, you know, 60 million miles away. After flying through space for six and a half months. And putting it on the ground.

And with, you know, temperature variations of 100 degrees Fahrenheit per day, that starts to make it challenging. Yeah, yeah, starts. So anyway, all that is an excuse, I guess, to say that, you know, that instrument was quite a bit late on its delivery to our first launch opportunity. And we had to fix a number of technical problems.

But the last technical problem we had, as you said, was we found that there was a leak in the vacuum enclosure of this instrument. Now, why did you need a vacuum enclosure, first of all? Well, a seismometer, in essence, is a mass suspended by a spring. And so that mass, well, you can say the mass moves up and down, but what actually happens is the mass tends to stay still while the planet moves up and down next to it. But in any case, what you want to eliminate is any air resistance or air effect on what we call the proof mass. In addition, we also want to insulate it quite well from temperature variations because I think variations of temperature of like a ten thousandth of a degree are enough to make quite a large signal on a seismometer. So a vacuum is a very good insulator.

So the vacuum around these seismometers is our first line of defense against temperature variations. We call it a sphere, but actually it's kind of a squashed spheroid. We pump it down and we weld it shut. That needs to hold its vacuum then for about three years by the time we have delivered it to the spacecraft and gone to Mars and operated for two years by the time we have delivered to the spacecraft, gone to Mars and operated for two years on the surface. And in the very last test that we did before we were going to deliver it to the spacecraft,

put it on there, test it, and blast off, we found that there was a leak. And this last test was actually operating it under Mars conditions. So we put it in a chamber, put six millibars of carbon dioxide in there, and then took it to sort of the warmest we expected on Mars and the coldest we'd expected on Mars and did that several times. And what happened is after we'd done that a few times, we noticed that there was some pressure starting to build up inside that sphere. And we noticed it because the seismometer sensitivity started going down. Wow.

Even in the near vacuum of Mars, this leak was pretty significant. Oh, yes. And to give you an idea of the size of this leak, I calculated that if the tire in my car was leaking at that rate, it would be about 50 years before I would notice one PSI difference. So this is what we call a hard vacuum inside there. And even a tenth of a millibar, it would be enough to start affecting our measurement. We tried to fix it. We tried to put some glop on it, hoping it would get into this little crack. Not the stuff you buy at the auto parts store. No, no. This is special scientist, you know, high, low temperature glop.

Yeah. But even the, you know, the things that we could get, they couldn't really withstand, put it through those huge temperature changes and you have thermal expansion contraction and it would just keep opening it up again. So we weren't able to come up with a repair that we could do in the very limited time we had before our launch. And we had to stand down from our 2016 launch. That's tough. But you're there now. We are there now. We spent the last two years, which of course, when you want to go to Mars, you have to wait 26 months if you miss your shot

because of the way the planets align. So instead of fixing that leak, what we actually did was go back to the drawing board, completely redesign that vacuum enclosure, make sure that we had no flaws in it because we actually, it was a mistake, honestly. We had feed-throughs which allowed the wires basically to feed signals and power between the sensors on the inside and the electronics on the outside. That feed-through was basically – it's like a ceramic plug with metal posts going through it. It was actually specced. The specification was it's good to minus 30 degrees C. Whoever was designing it, and I don't even want to know who that was.

They probably don't want you to know either. I don't think so. And it's not important. The important thing is we needed to go to like minus 100 degrees on Mars. And so it really wasn't quite designed to survive in the conditions on Mars. And so we went through, we made sure there were no other sort of misses like that, that we didn't pick up. When you build a spacecraft, when you build an instrument like that, what you're supposed to do is somebody designs it, does the best job they can, they know what they're doing. But almost everybody, except for me, of course, makes mistakes. I'm kidding. And so on a space project, you have, you know, people who check the people and you have people who check the people who check the people.

And somehow this just fell through the cracks, which happens occasionally. It happens, yeah. Space is hard. Space is hard. And, you know, this is just one of those details. I mean, when you think about trying to measure, you know, sub-Angstrom vibrations on Mars, the last thing you're wondering about is, well, what about the vacuum system? You think that that's just a thing that you get. But, no, you have to pay attention to every detail. And this one just got past us. But we've redesigned the vacuum system.

As you can imagine, we've tested the bejesus out of it. Many, many times up, down, sideways, going way past the temperature limits. And that vacuum system, something might fail on this mission, but it's not going to be the vacuum system. I can guarantee you that. Speaking of the testing, and it goes back to the exquisite sensitivity of this device, I read that during some of the testing, one of the problems you had was, and I don't know where this was happening, but you were picking up the surf hitting the California coast.

Oh, yeah, this is a standard problem with seismology is that anywhere you go on the Earth, no matter how far away it is, and in our case, you know, we had our seismometers in Denver where we were building the spacecraft and we wanted to do some testing of seismometers, so we had our seismometers in Denver where we were building the spacecraft and we wanted to do some testing of seismometers. So we put reference seismometers in Denver. But, you know, you can go to, you know, the center of the Asian continent as far away from the oceans as you can possibly get. And your sensitivity to your seismometer is limited by what we call the micro seismic background peaks.

what we call the micro seismic background peaks. And those micro seismic background peaks are noises that occur from the turbulence in the water, basically waves hitting the coastlines and the continental shelves. And you just can't get away from that on the earth. And the quietest site that you can find, that's your limit. So how big a problem is noise like that going to be on Mars? I mean, at least as far as you know right now. Well, noise is always sort of your first, second, and third problem in seismology because noise is what limits how small a signal that you can actually pick up. We can have seismometers that easily pick up, as I said, fractions of an atomic radius. But for those vibrations to be meaningful, they have to be actual seismic waves.

They can't be the wind shaking the seismometer around or the temperature going up and down and causing the seismometer itself to warp and move. Or even as a shadow passes over the seismometer, the ground actually expands and contracts and causes the motion of the ground. So all those noise sources, we have to either control or measure in order to make sure that we can either remove them from our signal or at least recognize them so that we don't mistakenly think

that they're seismic sources. I got to throw another one in because you mentioned it at lunch not long ago. When Phobos, the bigger of the two moons of Mars, goes over, it moves the surface of Mars. Yeah, yeah. It sets up a solid tide on Mars. And so if Mars had oceans, you would see the ocean tide going up and down. Since there's no oceans, the actual surface of the planet gets pulled up about roughly a centimeter as Phobos goes over every six and a half to seven hours.

I don't remember the exact period. And we can measure that with a seismometer as well, yeah. In fact, that's a key piece of information that we can actually use to probe the depths of the planet because the size of that tide depends on the properties of the core because if the core is liquid, the planet acts like a hollow ball, which is much easier to deform than a solid ball. It's like the difference between a tennis ball and a racquetball. You can squeeze a tennis ball with your hands.

You try to squeeze a racquetball, unless you're the Hulk or something like that, you're not going to get very far. And so by measuring that displacement very precisely, we can actually get to the size of the core of Mars. Now, because of issues with calibration and noise, that's kind of right on the edge of our measurement capability. But it turns out the longer we're there, since Phobos goes over every single day, we can actually use that repetition to sort of build up our signal to noise ratio. And perhaps after two years or three years, we can actually get a scientifically interesting number out of that. scientifically interesting number out of that. Is this seismometer just going to, once it's deployed,

monitor continuously on the surface? Yeah, and that's kind of the architecture of this mission is that we land on Mars, which is incredibly kinetic and a fast-moving process. I was going to call it six minutes of terror as a tribute to Curiosity. Yeah, we're about six and a half minutes. We get down a little bit faster than Curiosity. But once we're down on the surface, we still have quite a bit of work to do because the instruments are bolted to the deck of the lander. And, of course, what we want to measure is what's on the ground.

So we actually go through a process of deploying the instruments to the ground. We have to characterize the area that we have in front of the spacecraft, and then we have a two-meter robotic arm, about seven feet long, that then can grapple the instruments one at a time, pick them up, once we release their bolts from the spacecraft, and place it on the ground at a place that we select for being nice and flat and not having any holes or rocks. So we put our seismometer down and it has its own feet that then level it very precisely.

And once we're satisfied with that, we pick up our wind and thermal shield, which looks like an upside down walk that you could do some stir fry in with a nice shiny curtain around it that comes down and seals around it. So we put that on top of the seismometer to protect it again from the wind and temperature. And once that's deployed, we do our final deployment, which is our heat flow probe, which is we take the heat flow probe structure and put it onto the surface of Mars. And at that point, you know, we're done with the robotic arm deployment system, but we still have one step left, and that is getting that heat flow probe down into the ground. And we have a sort of little torpedo. It's about, oh, about a foot and a half, two feet long,

with a hammer on the inside. It's a little motor-driven hammer with a mass that squeezes up on a spring and knocks down about once every three seconds. And millimeter by millimeter, that thing's going to drive itself down five meters below the surface of Mars. Five meters, which is pretty good. At 16 feet, that's higher than the ceilings in most rooms. So that's a pretty good penetration. You're going to have the Guinness Book of World Records for digging holes on Mars. Yeah, except it must be the Guinness Book of Universal Records, right? I suppose so, yeah. It's not on the world, right?

So yeah, and of course, the instrument turns out not to be the mole. The instrument's actually the cable that it pulls down behind it. Oh, yeah. And on the cable, about every two feet or so, we have a little thermal sensor, a little thermocouple that measures the temperature very precisely. So we get the profile of the temperature as you go down this hole. And as you go down into a planet, you find this out on the earth as well, it gets warmer and warmer. So over 15 feet, it doesn't get much warmer, a few hundreds of a degree maybe, but we measure that temperature gradient, the increase very precisely. And by combining that with a measurement of the thermal conductivity, which is how quickly, or basically it's a measure of how much a rock

insulates, how quickly heat can go through it. Those two quantities allow us to figure out how much energy is radiating up out of the depths of the planet. And that, of course, gives us a measure of the energy available to drive geological processes, to drive volcanism, to drive tectonic motions, and to drive volatile species like water and other gases out of the interior up to populate the atmosphere even. So five meters, I mean, deep as that may be compared to how deep we've been able to dig in the past, just doesn't sound like that far.

This must, I mean, this thermal system in its own way sounds as sensitive as the seismometer. Yeah, we have to measure extremely precisely. Like I said, the total change in temperature is maybe a hundredth or two hundredths of a degree. And we need to be able to measure fractions of that to actually be able to get precise increase in temperature. And so we have a lot of electronics in there to allow us to get the relative temperature among these sensors very, very precisely. It turns out the accuracy, if you've taken a physics lab recently, you probably remember what the difference between precision and accuracy is. Otherwise,

we forget it after a while. But the accuracy is not so important, you know, whether it's, you know, minus 32.1 degrees or minus 32.15 degrees isn't so important as to make sure the difference between each of those sensors is very well done. And so, you know, we go through a lot of electronics tricks to get that to be extremely precise. Do you expect those measurements to vary for reasons coming from the interior, or is that going to be pretty stable? I mean, obviously, the surface temperature is going to change as you go through the seasons, But what about what's coming from below? What's coming from below should be pretty constant.

I mean, you know, it's decreasing with time on the, you know, billion-year timescales. But, you know, the heat coming from the interior is coming from two different processes. I mean, one is just the heat that was deposited in the planet when it was formed originally, you know, 4.5 billion years ago. Some of that heat is still trapped on the inside and trickling out little by little. The other component is the heat that's being generated by the decay of radioactive elements, mostly uranium and thorium, which are the long-lived radioisotopes. One of the big questions is how much of the heat coming out of the planet today is primordial heat, the heat from its birth, and how much of it is radiogenic that's been generated by these things, these other elements. And that then goes back to its thermal history, how quickly it lost its heat early in its history, how quickly it's losing its heat now.

heat early in its history, how quickly it's losing its heat now, and then, of course, that goes back to the evolution of the planet and the processes that happened early on, how much modification there's been since then. And the evolution of our own planet. That's right. And who's this instrument from? This is coming from Germany, isn't it? Yeah, the heat flow probe was designed and built in Germany. The hammering mechanism was actually coming from Poland. They turned out to be the experts in this, and the Germans and the Poles have collaborated on a similar instrument on Rosetta and one on Beagle 2, neither of which got to do their complete job, but did give us a lot of experience, give them a lot of experience in building the instrument that they made for InSight.

Well, hopefully third time's a charm. And good things do come in threes. Tell us about RISE from your JPL colleague. Do you pronounce it Faulkner? William Faulkner? Faulkner, yes. Faulkner, okay. Yes, so RISE is a radio science experiment, which means we don't actually have an instrument on the spacecraft.

So RISE is a radio science experiment, which means we don't actually have an instrument on the spacecraft. We actually use the radio system, which is a fairly sophisticated, we call it a transponder, which means that it receives and transmits. And it does it in a special way that doesn't actually interrupt the radio signal. So as it receives signals from the Earth that are generated by those huge dishes out in the desert from the deep space network. It receives that signal and then turns it around and transmits it back to Earth without a break. So we know exactly the chain that it goes through and the small amount of delay that we have measured inside the radio itself. We don't even break the shape of the wave. So we call it phase coherence. So it doesn't actually even interrupt that wave. And so it just turns it around and sends it back to Earth.

When it gets back to Earth, the dishes pick it up, and we're able to analyze that signal, analyze both the timing of the signal, analyze the Doppler shifting of the signal due to the relative velocities of Earth and Mars, and actually the relative velocities of the signal due to the relative velocities of Earth and Mars, and actually the relative velocities of the receiver on Earth and the receiver on Mars, the two radios. And through the magic of analysis, they're actually able to determine the location of

the InSight lander or the radio antenna on the insight lander to within six inches. And that's at a distance of 60 million kilometers average or something like that. But the precision of that, in fact, the accuracy of that measurement in inertial space that they've set up a coordinate system based on a quasar-based coordinate system. They can find that location within six inches. It's amazing. And, I mean, radio science. I mean, this has delivered so much great science from all over the solar system.

Right, and that's how they navigate spacecraft. That's how they know where a spacecraft is in outer space and how they understand how to modify its orbit to get to where they need to go. And, of course, you know, we've been, we meaning JPL, not meaning anything that I do, but, you know, we've been able to, you know, just nail these entry, descent, and landing targets with an amazing degree of accuracy. Better and better. Yeah.

Right. I should have asked you when we were still talking about size, how many Mars quakes do you expect to experience? That's an excellent question, one that we had to satisfy a lot of people when we first proposed this mission. We've done several lines of analysis, starting with, well, let's see, Mars is bigger than the moon and smaller than the earth. It's probably about halfway in between. And that gives you a number. You can look at the theoretical thermal history of Mars and see how much it has cooled off over the last 4 billion years and how much it's cooling off today and estimate that. We have to estimate it because we don't have the number from our heat flow probe yet, but there's a range there.

And we think that Mars quakes are driven by sort of the thermoelastic cooling of the planet as the planet shrinks. The crust kind of crinkles around it, and those crinkles are all Mars quakes. So you can estimate sort of a seismic potential from that. And then finally, we've looked at all the faults that you can see on the surface of Mars. And Mars is crisscrossed by faults. You know, there's wrinkle ridges where the crust has been pushed together. There are rifts where the crust

has actually been pulled apart and the floor dropped down and you have motion along faults on either side. And there's even a few strike slip faults that you can find on the surface. And so we've gone through the exercise of counting up all those faults and putting dates on all of them. And by date, I don't mean August 30th, 5 billion BC. We know that this set of faults happened 3 billion years ago, and this

set of faults happened 2 billion years ago, and this set of faults happened 1.5 billion years ago. And then we can put those lines on a plot and extrapolate it with an exponential function to the present and get an estimate of what we think that... And all those numbers, more or less coincidentally, hopefully because they're kind of right, tend to be about the same number. And that number indicates that we should see something like a few dozen kind of globally observable earthquakes on Mars in the two-year lifespan of our prime mission. Plus or minus a factor of 10 or plus or minus a factor of 100 because this is really a discovery mission. I mean, we're going and measuring something that's never been measured

before. No matter how smart you are as a scientist, you always have to remember that until you actually measure it, you really don't know. It's all hypothesis and theory until then. That's why we do it, right? Absolutely. It is nice, though, when the existing data kind of all converges. Yeah. And sometimes that can fool you, but it usually is a good sign. Yeah, yeah. All right. Can't wait to get to the first of those. So you know that this being the Planetary Society, a child and part of the late, great Bruce Murray, the former director of JPL, who, of course, was the champion of cameras on spacecraft. You do have some cameras. They're not the main part of what you're doing, but they're essential to the work that InSight's going to do.

Yeah, and as a geophysicist, I sort of have a bias against cameras because, you know, every spacecraft has to have cameras on it. But, you know, geophysical instruments are sort of not so sexy, not so exciting. And so, you know, we always feel a little bit resentful of the Hollywood instruments, which are the cameras. But I had to concede that cameras are very useful instruments. And we use the cameras on InSight. We don't consider them to be one of our instruments. We call them sensors, support sensors. So we kind of denigrate them to second-class citizenship. But they are very important, and we're going to get some really cool pictures out of them. But the main reason they're on there is actually to aid in our deployment process. So when

we put these instruments down on the surface, we don't want to put the seismometer on top of a rock and have it sit there, fall over, or fall down into a hole and not be able to level it. So we're going to use the camera, which we actually have attached to the robot arm in order to save ourselves the expense and complexity of a separate camera mast. We just attach it to the forearm of the robotic arm, and we can point it wherever we want by moving the arm around. We can take a mosaic of the entire workspace, what we call a workspace, which is everywhere the arm can reach, and we can do that in stereo. So we take overlapping pictures and put them together so we get a 3D map of this area in front of our lander,

which is about, it's roughly three to four square meters. And we actually went out of our way to change that camera from black and white camera. These are actually leftover cameras. We didn't actually even have to build these cameras. They were left over from curiosity because when you build an instrument to put on a spacecraft, you know, you build the ones that you're going to fly and then you build two or three more just in case something happens, you know, somebody drops it when they're putting it together or something like that. So you usually have, you know, hardware left over at the end. And we were able to take advantage of that and get some of the spare cameras from Curiosity. And these are like the

HAZCAMs and NAVCAMs. Yeah. So we have one of each. We have one of the HAZCAMs, which is a wide angle kind of fisheye camera. The rover's, you know, use to sort of see a wide-angle view right in front of the wheels to sort of aid in the details of where their wheels are going to go. And we bolted one of those on the front of our lander so that we can see basically our entire workspace with one camera. And there's some distortion to it, and the resolution is not as great as some of them, but it gives us a synoptic view, sort of a full view of this workspace in context. And then the second camera is one of the nav cams, which is a higher resolution camera that we can make our mosaic

of the workspace in higher resolution. We don't have anything like the really high resolution cameras that the other rovers carry. Our best camera is going to be a Leica Navcam, which is still a pretty decent little camera. Enough to make people like me and other members of the public fans happy. I certainly hope so. And then we did go out of our way. We decided to open these cameras up and we put a to open these cameras up and we put a filter over the sensor array to turn it into color. So we took a tiny hit in resolution to get a full color camera. So we won't be bringing back black and white pictures. One of the people on our team said they could not imagine after all these years, pictures we get down from Mount Mars are suddenly just like newspaper pictures from the 1970s. He says, NASA would be the laughingstock if we did that. So we finally agreed and took the

trouble and spent the money to colorize these cameras, and we'll get back full-color pictures of the Martian surface with them. I don't think you'll be sorry. I don't think so either. And I thank you on behalf of a lot of people who listen to this show. Yeah, and even as a geophysicist, I do love the pictures. I do. It comes out. Anybody who looks at this entire lander is going to see its lineage. Anybody who listens to this show is going to remember the Phoenix lander that made it to Mars almost exactly 10 years before your launch.

Not a coincidence, is it? No, the lander that we're using is almost a carbon copy of the Phoenix lander. And again, I mentioned this before, this is a cost cap mission. This is a discovery mission. We actually won this mission in a competition. We put in a proposal, and the NASA ground rules for these kinds of proposals are you cannot exceed this cost and you must do great science. And anybody can put together a proposal, submit it to NASA. The time that we did it, I think there were 27 proposals that we were

competing with. And those are 27 great, I mean, you start reading proposals from planetary scientists, you just, you start reading proposals from planetary scientists, you just, you come away crying knowing that you can't do all those missions. Yeah, in a perfect world. So anyway, we were in a competition and we could not go over this cost cap. And so we have to think of lots of ways to save money. Getting used cameras, that was one of the ways that we did this. I'm thinking of the arm too.

You recycled the arm. That's right. The arms recycled as well. That was supposed to fly on a 2001 mission that ended up being canceled and it's sat in storage for the last 10 years before we picked it up and refurbished it. So the spacecraft we're using is just about a carbon copy of the Phoenix spacecraft, and that saved us the expense of designing a new spacecraft. So we didn't have to reinvent the wheel. We had a proven spacecraft that was able to land on Mars, which is no mean feat. That's a tough thing to do.

It did it successfully, and so by going back to Lockheed Martin, which is the company that built it, and saying, we want to do things as close to Phoenix as possible, how cheaply can you sell us a spacecraft? And since they don't have to hire an army of design engineers to redo it, they were able to give us a pretty good bargain basement price on this spacecraft. And so when you look at the spacecraft, except for the instruments that are bolted to the deck, which are a completely different set of science instruments, it is really just the Phoenix spacecraft.

I mean, the details that have changed, I think we added six inches to the solar arrays to give us a little bit more power. I think we added six inches to the solar arrays to give us a little bit more power. We beefed up some of the struts just a little bit so that we could stand a little bit higher parachute loads when we're coming in. But, you know, those are things that only an engineer with a micrometer would ever notice. But, yeah, this is the Phoenix spacecraft, and, you know, we're happy to have something that's already been successful once and use it again. If it ain't broke. I was so envious of my colleague, Emily Lakdawalla, because she got to go north to Vandenberg Air Force Base and go into the clean room with you.

You both look great in your bunny suits. And I should say that this is actually going to be, it's available now in the current edition of our Planetary Post show, hosted by Bob Picardo, board member of the Planetary Society. And he cuts away to Emily being a reporter and talking to you in that clean room. And we'll come back to why Vandenberg in a moment, but obviously a lot of concern, as there always is when you're sending something to the surface of another world, about making sure you take as little of Earth as possible, at least the stuff that you don't intend to send to Mars, right? Planetary protection is what I'm getting at. That's right. And of course, you know, the United States is a signatory to, you know, an international treaty agreement that specifies, you know, how much biological material that you can take to Mars. And so there are protocols about, you know, how many spores per square

centimeter and, you know, what the biological load is. And it's extremely small, even though you're going through, you know through the vacuum of space for six months and being exposed to burning heat on the sun side and bone-chilling cold on the shadowed side. Don't forget the radiation. And the radiation in interstellar space, or interplanetary space, rather. There are still things that can survive that, statistically speaking. And so, yes, we have very strict rules on when we're building this, how clean we have to keep it, scrub it down at the end, we scrub it with alcohol over and over again, every little nook and cranny of the spacecraft. And that goes all the way up to when the whole thing is sitting inside the

fairing on the rocket. In fact, there are people, as we speak, there are people up there now with little swabs, you know, little Q-tips with alcohol on them, scrubbing every square centimeter inside the fairing and making sure that there are no, you know, germs or spores that we're taking to Mars. Wow. Did you have to meet or do you have to meet the same standards as, let's say, the Curiosity rover? We have slightly lower standards that we have to meet. And the reason is because, first of all, we're not going to a region that is expected to be able to support life, terrestrial life. So we're going to the equator of Mars, which means it's extremely dry.

You get water that's condensed as ice, you know, as you get up into the high latitudes. Yeah, as Phoenix found, just digging a few centimeters. That's right. But that ice is not stable at the equator, at least not anywhere closer to the surface than maybe a few kilometers down. And then because of the heat flow coming in from the interior, it probably isn't stable there either, although there may be an aquifer, there may be a water table as you get down several kilometers. We don't know, but it's certainly nowhere near the surface. So because it's not something that is thought to be conducive to life surviving, we're allowed to satisfy somewhat relaxed standards.

Also because we're not doing any experiments looking for life, and no one's intending to come anywhere near us to do those kinds of experiments. Again, you know, so there are about three different levels of planetary protection that are specified depending on how close you come to a potentially habitable zone, which means a zone that can support water, even tiny bits of water in between the grains of the rocks, and the kinds of experiments that you intend to do with it. InSight is not going alone on this mission. You're bringing along a couple of CubeSats, a format for spacecraft that we care a lot about here at the Planetary Society because of our LightSail 2, which is a CubeSat, of course. I've read that they're just kind of test platforms, but they might actually be able to help InSight out a little bit, at least as it's getting down to Mars?

Yeah, these CubeSats, they're experimental craft, so I'm required by my bosses to emphasize that InSight does not depend on these in any way, which is absolutely true. But it is a really interesting experiment. These are technology demonstration spacecraft. They're about the size of a briefcase. I mean, really, really small little spacecraft. really small little spacecraft, and yet they're designed to fly and survive in deep interplanetary space, which no CubeSat's been put beyond the orbit of the Earth as far as I know. These were built on a shoestring budget. I'm sure you're familiar with that as well. Yeah. They were built on a shoestring budget, which is kind of the paradigm for CubeSats.

built on a shoestring budget, which is kind of the paradigm for CubeSats. And there's several really kind of cutting edge technologies that they're putting on there. It has its own propulsion system to make its own trajectory adjustments. It has its own solar power system. Plus it has a dual communication system because the job it's going to do if it gets to Mars is to actually relay the data that InSight will be broadcasting as it lands, as it descends through the atmosphere and lands. We'll be getting that data back through MRO, through Mars Reconnaissance Orbiter, but the way that the Mars Reconnaissance Orbiter works is it records the data for playback at a later time. So it'll probably be four to six hours before we get that data back, which is fine, technically speaking.

But if you're sitting on landing day in front of your consoles in Southern California wondering what happened to the spacecraft. Biting your nails. Yeah, you can lose a lot of nails in six hours. So it would be really cool if this works because it will – if they get to Mars and if they operate or even one of the two operates, we'll be able to see our landing data, our descent landing data in near real time.

There's just a few second delay and then, of course, the light delay getting back to Earth. time. There's just a few second delay, and then, of course, the light delayed getting back to Earth. But the way that this experiment is set up is that actually all the technology goals of the CubeSat will be satisfied in the first few days of its flight. You know, they need to see whether these things can survive launch, whether they can survive the injection into the Earth-Mars trajectory, and turn on several other systems and show that they can survive in deep space. And so if they last for a few days, that will be considered a raving success for these things. But, of course, everyone hopes, particularly the people who put their heart and soul into building these things

as carefully as possible, they're hoping that they'll get all the way out to Mars, do their job of relaying our data back. Wouldn't that be cool? Although I'm glad they're not essential to the mission. Absolutely. Back to Vandenberg. Why are you launching from the central California coast? First time ever for a planetary mission like this.

Well, the short answer is because we can, which is not always the case. In fact, I don't think it's ever been the case before. And that's because of the physics of launching a spacecraft into orbit around the Earth tell you that, first of all, rockets are expensive. And the bigger the rocket you have, the more you're spending. And so we tend to try to get the smallest rocket possible to just barely get us to where we need to go. Otherwise, you're just basically leaving money on the table that you could be spending on science. When Phoenix was built, it was designed to fit onto a Delta 2 launcher. A Delta 2 is a rocket. It's a relatively small rocket. Rockets are not small,

but this is relatively small. By launching from Florida, you want to launch over the ocean so you're not, you know, in the case of a disaster, you're not raining down on an inhabited area. So you launch eastward and you're launching in the same direction that the earth's rotating. And so you're using the earth's rotation, which is about, I don't know, about three kilometers per second, I think, at that latitude. The closer you get to the equator, the faster you go. So that is velocity that's helping slingshot you into orbit. Come all the way up to 2018 with InSight, InSight is the Phoenix lander. And so we are pretty much stuck with the size of the Phoenix lander. And even if we wanted to build

it up, we couldn't really because the entry, and landing system is sized for a certain amount of mass. And so we're stuck with how big the Phoenix lander is, which is about 360 kilograms dry on the ground. So we can't really grow in size. But meanwhile, the Delta II launcher has left the inventory. They no longer make them, use them. The smallest launcher that's available to us is an Atlas V. So we are using the smallest of the family of Atlas Vs. It's a 401, which means it's the small fairing, the small nose cone, which is four meters in diameter. The zero means there

are no solid rocket boosters. Scrapped on around the first stage, yeah. Right. And the one means that the Centaur upper stage has one rocket motor in it, and there's a variant with two. So this is sort of the smallest launcher that is qualified for a planetary launch, and that means that you can't just go out to anybody's garage and buy a rocket. You have to have something with a pedigree

and a 90% plus success ratio for launches so that this one-off, one-of-a-kind, nearly billion-dollar spacecraft isn't left in the ocean somewhere. So we have this Atlas, and it turns out it has about twice the capability of the Delta, which means that we don't need no Earth slingshot. We can launch into a polar orbit, which doesn't take any advantage of Earth rotation at all, and then punch ourselves out towards Mars directly. And so we had the option of going either from the Eastern Test Range, the Kennedy Space Center, or from Vandenberg Air Force Base, which is where

NASA and the Air Force go to launch polar satellites, which are most weather satellites and reconnaissance satellites, also known as spy satellites. They go into a polar orbit because that means that the whole Earth rotates underneath you as you're going into orbit, rather than if you're in an equatorial orbit, all you ever see is the equator. So there are reasons for different orbits. And so that's why we have one on the west coast and one on the east coast for these two different kinds of orbits. And so we can go into a polar orbit. So we had a choice.

And it turns out that because of this advantage that the Earth's rotation gives you, there's a traffic jam of satellites that want to launch from the East Coast. Planetary launches usually take priority, and you have to block out a certain amount of time for them. And so by moving this to the West Coast, which doesn't have nearly as much traffic going out of it, we actually relieve a lot of the congestion at the launch pad on the East Coast and make less of a headache for NASA for a lot of the other satellites that they're trying to launch. And thank goodness, as you implied, the Atlas series, the Atlas V, it's a very reliable rocket. It's amazingly reliable. I mean, this is a great rocket. It has well up into the high 90% success ratio.

Going back, I don't know, 15 or 20 years, I mean, the Atlas, I don't remember when the Atlas V variant took over from the Atlas IV, but the lineage goes all the way back to the 1960s. Mercury astronauts. Yeah. Yeah. This is great, but you can't tell me

you aren't at least a little bit anxious. Or maybe you can. I'm not that anxious. I mean, I've been up to Vandenberg several times and I've, you know,

rubbed shoulders with the launch people and these guys are, I mean, they are the best. Plus, I mean, they're just so solid and down to earth. I mean, I work with engineers all my career at JPL and some of the most brilliant engineers in the world. And, you know, they have an imagination that's incredible.

But if, you know, if your life depended on it, nothing personal against any of those people, the men and women that I work with. But it's a different kind of class of people that launch things because they're working with basically giant explosives. And they're working around it all the time. They have to be solid and on it all the time. And they are. What's the term? Steely-eyed rocket men, I think. And women nowadays. Yeah, right.

And women nowadays. Yeah, yeah. And it's funny. So I went up and took a tour of the launch pad. We're launching from Slick 3E, which is Space Launch Complex 3 East. So Slick 3E. Three different people that were showing me around just tell me, the perfectly straight face says, different people that were, you know, showing me around, just tell me, you know, the perfectly straight faces, this is the best launch pad in the world. And they were absolutely, you know, they were serious. And then they explained to me why they thought so. And they were just so proud of this particular launch pad that you don't want to go and work with these other guys. This one, this one's the best. And so I really do have a lot of confidence. I'm saving

all my fingernails for entry, descent, and landing. That's going to be nerve-wracking. When did you first start to dream of doing this kind of mission? This kind of mission, I started working seriously on probably, I'm thinking, 1988, 89. It's been a long time. And I shake my head, but this is not out of the ordinary that you have a 30-year history with essentially what we'll be launching next week. That's true. I mean, I know PIs of other missions that have spent 25, 30, 35 years working on it. I think Gravity Probe B, I think, was originally conceived back in the mid-60s, and I think it finally launched a dozen years ago or something like

that. New Horizons and others. Yeah. So getting a mission together, I mean, there are some people who've had a mission idea, put in their proposal, got it selected, off you go to Mars, six years start to finish, and God bless them. But I think it's a little bit more likely that you have an idea and, first of all, most of our ideas aren't fully formed the first time we get them. And I've learned a lot over the last 25 years on how not to do a Mars mission. They were pointed out to me in various proposal reviews. One of the jokes, my standard joke is that I figured out a dozen different ways how to fail in a Mars mission. And once you've eliminated all the ways that fail, all you have left is success. Yeah. Isn't that great? It's easy from that point, I guess.

Yeah. So yeah, it's a tough business. And like I said, there's a lot of competition of great ideas, great places to go. There's more science questions than I think the human race will ever answer. And so our curiosity just keeps on pushing outward more and more. And so you have to have a great goal. You have to have great ideas and great people, you know, coming up with implementation. And then you have to be a little bit lucky to kind of excite somebody, some review panel, get them a little bit more excited about your particular mission than the other ones. And that's very subjective.

I think on, you know, when you get down to it, you have a half a dozen missions that are all low risk, all great science. Which one's the most exciting? And that's subjective. That really comes down to some very human qualities. And we just happen to hit the magic mix, get the right stuff at the right time. And I'm incredibly grateful for that. The right stuff is right.

Congratulations on reaching this point after going through that very human process, where we are now literally, if you go to the website for the mission, and all you have to do is Google Insight Mars, I-N capital S-I-G-H-T. Or we'll have the link, of course, on the show page at planetary.org slash radio. And with any luck, we'll be up there feeling Mars move under us in barely more than half a year. I just got one more thing to thank you for, and that is taking my name along with you. Yes, yours and 2.4 million other people. Yeah. Oh, that was a lot of fun, actually. Because of our launch slip, we were

able to actually do this twice because we collected names, you know, back in 2015 for the 2016 launch, and we engraved them on a chip. And we left that chip on the spacecraft for the two years while we were waiting. And meanwhile, we brought that whole system back up again and said, hey, if you missed it the first time around, here we are. Send your name in. And we put together another chip. And right now, again, we're a Guinness World Record holder for the most number of names shot off the surface of the Earth. At this point, we beat out Curiosity and the Orion. I'm sure that Mars 2020 has their sights set on us.

But for right now, I'm going to bask in the glory of having the most names on a microchip going outside the gravitational well of the Earth. And hopefully soon basking in the glory of great science as well. Thank you. Thank you, Bruce, very much. And what do you say? I don't know if best of luck is appropriate at this point. Go Insight. Go Insight.

Go Insight indeed. Bruce Bannard, he is the principal investigator for the Insight mission and a principal research scientist at the Jet Propulsion Laboratory. Thanks again. You're welcome. Time for What's Up on Planetary Radio. Bruce Bett is the chief scientist for the Planetary Society, and he is back with another look at the night sky and some great responses to the trivia question of a couple of weeks ago. And even more than that.

Welcome. Thank you, man. We get lots of terrific mail when people enter the contest. There's a place for them to put a special greeting or message, as it says, if they enter through the form that we have at planetary.org slash radio. Then people just send us email. Thank you to everybody. I try to respond to everyone who has something nice to say. Eric Sonhammer in Sweden.

He says, thanks for a very awesome show. What's up is hilarious. He says without a, without a trace of irony there wasn't any kind of emoticon to try to indicate that he was being sarcastic no awesome let's go with it let's accept it face value face value we'll try to live up to that today you know what else lives up to our expectations matt i bet it's the night sky the night sky and the cool looking stuff there jupiter rising it's the night sky. The night sky and the cool looking stuff there. Jupiter rising, it's about to hit opposition on May 8th, which means it's on the opposite side of the Earth from the sun,

which means it rises around sunset and sets around sunrise. It is at its closest for the year, although it isn't a huge difference. It's enough of a difference to make it a little bit brighter. It's certainly super bright over in the east in the early evening. If you look over in the west in the early evening, we've got super bright Venus. And then coming up in the middle of night and up high in the sky by pre-dawn are Mars and Saturn. And you can check out the moon between Mars and Saturn on May 5th. Mars brightening is now reddish and brighter than Saturn and will keep brightening for the next

few months until it reaches opposition. And you said this is going to be a pretty close pass with Mars in a few months. You told me at the office the other day. Yes, I did. And yeah, we don't have to worry about it hitting us, but it's been since the particularly close opposition of 2003. So Mars goes through cycles because of its elliptical orbit. So each opposition is a little different. And we're on the good side of the cycle now. So it's actually going to be brighter than the brightest star in the sky. Bright as Jupiter.

Okay. All right, we move on to this week in space history. It was this week in 1961 that Alan Shepard became the first American in space. Yeah. A little suborbital jump. We move on to random space fact. The poorly named planetary nebulae have nothing to do with planets. A planetary nebula is a shell of ionized gas that was blasted off by a star during the last stages of its life when the star was a red giant.

leading astronomers of the 1700s, those wacky, wacky astronomers, to liken them to planetary disks, thus generating the ridiculously confusing name planetary nebula. My astronomy professor in college, the second most frustrating thing to him after how too many people pronounce Uranus was that planetary nebula are so-called because, like you said, they have nothing to do with planets. Don't get me started on these things. Oh, it's such a historical science. Let's move on to the trivia contest. And I asked you, in Greek mythology, who were Andromeda's mother and father?

And I gave the hint that all three have constellations named after them. How do we do? Well, here's an incorrect answer to get us started from Torsten Zimmer in Germany. He says, in Greek mythology, Andromeda is the lesser-known brainchild of Gene Roddenberry, which is true as far as it goes. We get any other answers? Yeah, we got a whole bunch of regular answers because this one was very popular. Edward Lupin, first time I heard from him was over three years ago. But as far as I know, he's a first time winner with this. He says it was Cepheus, or is it Cepheus, and his wife, Cassiopeia, who had Andromeda as their offspring. Is he correct?

That is correct. Edward, congratulations. You have won yourself that coveted Planetary Society rubber asteroid and a Planetary Radio t-shirt. Also, a 200-point itelescope.net astronomy account. What a haul. A 200-point itelescope.net astronomy account. What a haul.

Perry Metzger suggested that perhaps this week's rubber asteroid can just remain in circulation, owned for one week each by each contest winner, sort of the way the America's Cup is in perpetual competition, just gets handed off to the new winner each time. I don't know if a rubber asteroid would hold up well enough to go through all those rounds. That would be a logistical complication. Yeah, I suspect. As you might also suspect, we got a whole bunch of other entries, like from Eric O'Day in Medford, Massachusetts.

If you know the story, it's a very dramatic story, of course, about Andromeda and, you know, Perseus and Pegasus gets into it and sea monsters. He says family drama included attacks by sea monsters, rescue by classical heroes, also represented by constellations. He says, I guess the sky was the tabloids of 4,000 years ago. Indeed, it apparently was, at least for the Greeks. Christopher Mitten in Carbondale, Illinois, where, of course, I drop in now, and then it seems, at Southern Illinois University. He says that the constellation Cassiopeia contains some of his favorite objects, including the owl cluster, while Stan Shull in Kirkland, Washington, says Andromeda has one of his favorite galaxies, the gorgeous edge-on spiral NGC 891.

But a sad comment from Michael Booth in Australia. From 42 degrees south, we never see Andromeda's parents. They're too far north toward Polaris. From September to December, however, Andromeda appears in our very short summer evening sky, hugging the northern horizon with M31, the Andromeda Galaxy there in a must-see object. It is indeed a must-see object. We close with Dave Fairchild, our poet laureate. Oh, what a mother was Cassiopeia.

She bragged on her daughter too much. Poseidon with Triton created a monster that wanted her country for lunch. But Cepheus, her father, just couldn't be bothered, so chained up his daughter instead. Who knew that this drama would be a space opera enshrined in our stars overhead? Nice work, Dave. He always does good work. This one's particularly good. We're ready to move on to yet another contest.

What star is most commonly referred to as the Demon Star? The Demon Star. Wow. Where do they enter? Go to planetary.org slash radio contest. And you have until May 9, 2018 at 8 a.m. Pacific time to get us this answer. And somebody out there with that right answer is going to win a Planetary Radio t-shirt. Not the Society t-shirt.

Both are nice. But the Planetary Radio t-shirt, of course, is cooler. Don't tell the boss I said that. You can check them all out at chopshopstore.com because that's where the Planetary Society store is. And a 200-point itelescope.net account. Society store is, and a 200-point itelescope.net account. 200 points worth of observation on that worldwide nonprofit network of telescopes. We're done.

All right, everybody, go out there, look up in the night sky, and think about your top three spices in order. Thank you, and good night. That's easy. They'd be oregano, oregano, and oregano. You are quite the oregano fan, aren't you? No doubt about it. And he is Bruce Betts, chief scientist for the Planetary Society, without a doubt, who joins us every week here for What's Up.

We're hilarious. I'll keep that. I've heard from many of you about last week's great live conversation with Emily Lakdawalla and others. I neglected to thank Planetary Society volunteer Rich Evers for helping us get that special show recorded. Rich is part of a great podcast called The Drunken Taoist that you might want to check out. Our friend Jeff Bennett also has something new that's worthy of a look. It's an Eclipse app for iOS and Android called Totality. Jeff and Big Kid Science have made it available absolutely free,

because that's the kind of great science popularizer he is. Last, not least, I'll be at this year's Humans to Mars Summit in Washington, D.C., May 8, 9, and 10. They've just added brand new NASA Administrator Jim Bridenstine as a keynote speaker. If you can't join me there in person, consider checking out the live webcast that yours truly will be hosting. All the info is at h2m.exploremars.org. Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by its members who like to dig deep. Mary Liz Bender is our associate producer.

Josh Doyle composed our theme, which was arranged and performed by Peter Schlosser. I'm Matt Kaplan at Astren.