Planetary Radio • Aug 12, 2020

Another Ray Gun Heads for Mars. We Hear It Working.

On This Episode

20120917 wiens with chemcam

Roger Wiens

SuperCam Prinicpal Investigator for Los Alamos National Laboratory

Betts bruce headshot 9980 print

Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

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Mat Kaplan

Planetary Radio Host and Producer for The Planetary Society

First there was ChemCam on Mars rover Curiosity. Now, SuperCam is on its way to the Red Planet aboard Perseverance. We’ll talk with principal investigator Roger Wiens about the new and improved, laser-firing instrument that delivers rock spectra and other science from a distance. SuperCam’s microphone will finally let us listen to the Martian wind and more. Mastcam-Z is right next to SuperCam on the Perseverance mast. You’ve turned it into great acronyms that we’ll share in What’s Up.

Integration of SuperCam’s Mast and Body Units
Integration of SuperCam’s Mast and Body Units The two parts of the SuperCam instrument are shown mounted on an optical bench. The two units are connected by electronic cables and an optical fiber (blue cable at left). LANL
Mars 2020 SuperCam transmission spectrometer
Mars 2020 SuperCam transmission spectrometer Cut-away view of the transmission spectrometer used for remote Raman spectroscopy on SuperCam. Light enters from an optical fiber bundle on which the aperture slit is mounted. The dichroic (left) splits light into two traces. Of the two side-by-side gratings, one is a compound, splitting the light into a third trace, all of which are intensified and collected by a single CCD detector which reads them in three sequential digitization windows. LANL

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Trivia Contest

This week's prizes:

Dr. Louis Friedman’s new memoir Planetary Adventures: From Moscow to Mars.

This week's question:

What is the wavelength of the SuperCam laser you’ve been hearing about?

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Wednesday, August 19th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

What was the only completely unintended splashdown of a spacecraft carrying humans?


The winner will be revealed next week. 

Question from the 29 July space trivia contest:

The stereo camera atop the mast on the Perseverance Mars rover is called Mastcam-Z because it is a mast-mounted camera with zoom capability. Your challenge is to create an acronym that contains all letters in that name!


Listen to the show to hear the winning Mastcam-Z acronym suggestions!


Mat Kaplan: Another ray gun heads for Mars, and we'll hear it working this week on Planetary Radio.

Mat Kaplan: Welcome, I'm Mat Kaplan of The Planetary Society, with more of the human adventure across our solar system and beyond. Roger Wiens heads the SuperCam instrument on the Perseverance rover. Its laser will heat up our search for past life. Well, its microphone will finally let us listen to the wind blow on the Red Planet.

Mat Kaplan: Our great conversation is coming right up. SuperCam's big eyes up on top of the Perseverance mast sharing that space with the stereo vision, Mastcam-Z. We'll hear your great attempts to turn that name into a NASA acronym in today's What's Up along with Bruce's guide to the night sky. Shining brightly in that sky is my Jupiter, a beautiful new view of the planet tops the August 7 edition of the Downlink which also includes these headlines.

Mat Kaplan: Mars once had liquid water on its surface but there may have been less than some hoped. A new study says most of the water may have been hidden under the surface in giant ice sheets. This could actually be good news for a possible life as it might have been better protected from radiation and other challenges.

Mat Kaplan: Back to Jupiter for a story we'll take a deep dive into next week. According to a new study, the big bully may have prevented the formation of more worlds in our sun's habitable zone. Of course, we knew the early solar system was a dangerous place what with big chunks of planet-forming materials slamming into everything.

Mat Kaplan: China's Yutu-2 has found more evidence of this below the moon's surface. The little rover's radar sees multiple layers of impact rock dating back more than three billion years. As always, you'll find much more at including a chance to join Bill Nye for the landing of Perseverance in February of next year.

Mat Kaplan: A quick mea culpa before we proceed, I said in last week's show that the Super Draco rocket engines on the Crew Dragon capsule fire to begin the spacecraft's reentry. Wrong. That job goes to the smaller Draco engines. The Super Draco's are key components of the emergency escape system. Kudos to those of you who caught this error.

Mat Kaplan: Roger Wiens has joined us several times but it has been a while since he last dropped by. Now, with the Perseverance rover on its way, he's back to tell us about the descendant of Curiosity's brilliantly successful and just plain brilliant, ChemCam. As you'll hear, SuperCam builds on that success but promises much more and it includes a tiny microphone that will deliver even more science as it lets us listen in on the Red Planet.

Mat Kaplan: Roger's a fellow at the Los Alamos National Laboratory in New Mexico and a member of the lab's Planetary Exploration Team. He remains principal investigator for ChemCam as it continues its work and has the same job for SuperCam. He joined me from Los Alamos a few days ago.

Mat Kaplan: Roger, great to be talking with you again. Congratulations on having yet another, oh, I have to say a ray gun on its way to Mars.

Roger Wiens: Well, thanks, Mat. It's just great to ... We're just jumping for joy.

Mat Kaplan: I imagine you are, and I cannot wait. And neither can anybody who listens to this show cannot wait for that next seven minutes of terror and that mast unfolding and SuperCam being able to start its work on the surface of Mars. How is SuperCam going to build on the success of ChemCam? They're similar in a lot of ways, aren't they?

Roger Wiens: We certainly built on ChemCam when we designed SuperCam. So that's a very nice feature because ChemCam has done just an awesome job of exploring Gale crater on Mars. But SuperCam takes the chemistry that ChemCam can do and it adds two mineralogy techniques, not one but two, and then it also adds to the imaging by making it color imaging. And then we have a microphone on board as well.

Mat Kaplan: Well, we're going to get to all of those, particularly that microphone. As you might imagine since that's an old dream of The Planetary Society that you're making a reality or we certainly hope it will be in February. Take us back though first to Curiosity and ChemCam which just celebrated eight very productive Earth years on Mars a few days ago as we speak. We're just past that eighth anniversary.

Mat Kaplan: It sounds like ChemCam has been able to accomplish everything you hoped it would and maybe more?

Roger Wiens: Oh, absolutely, Mat. In fact, well, let me just start with saying ChemCam is the large eye. It's like a four-inch diameter eye on the top of the rover Curiosity. It's like a Cyclopes' eye up there and we fire the laser out of that eye at rocks and soils up to about 25 feet away from the rover, about seven meters.

Roger Wiens: The laser beam is a very rapid short pulse with high energy and it actually creates a small plasma, little briefly going flash on the target. The telescope that we have behind that eye actually looks at the rock or soil and that plasma and it actually tells us the composition by looking at the atomic emission spectrum. And so, by calibrating that, we can tell you how much silica and aluminum, carbon, other elements there are in these rocks or soils on Mars.

Roger Wiens: And we can do it without ever driving up to that rock or soil. We can do it some distance away. And in fact, the laser shockwave actually blows dust off of the surface so that we can get a nice clean analysis of that surface and then we get closeup images as well. So, we do all of that with ChemCam.

Mat Kaplan: A laser broom in a sense in addition to everything else that it does?

Roger Wiens: Yeah.

Mat Kaplan: Tell me about the laser. Is it the same laser in SuperCam that you have in ChemCam and how powerful is it? I'm tempted to ask if you can set it for stun.

Roger Wiens: Yeah. At the landing time of Curiosity, we got some pictures on the internet from, I don't know if it's people joking or enthusiasts, but they had some large explosion happening. So I don't know if they were thinking that this came from a defense lab. But anyway, we don't do anything like that.

Roger Wiens: The laser itself puts out about 30 millijoules that when it's translated out to the target, it's about 12 millijoules. It is something that, like we said, makes a small spark. If we shoot a lot of laser pulses, we can make a small pit in the rock. But it doesn't destroy the rock by any means. It's just a very small pit well under a millimeter.

Roger Wiens: That is still great for us scientifically because it allows us to probe the very surface of the rock to look for weather encodings or other things. And then we can also average together the spectra we get from that to get a more accurate reading. So, that is a neodymium KGW laser. It's a little bit unusual but it was built to withstand a fairly large temperature range on Mars.

Roger Wiens: The SuperCam laser is almost exactly the same but it's more typical neodymium YAG laser that most people hear about much more often. So, it's a slightly different crystal. We found a different way to accommodate the thermal range and so it's much easier to use the more traditional or more widely used on Earth type of crystal. And it's, again, about almost exactly the same energy as the ChemCam laser.

Mat Kaplan: One of the things that amazed me about ChemCam and will about SuperCam is this ability that you have given both rovers to sort of reach beyond their grasp. The fact that SuperCam, as ChemCam has, will be able to target rocks that are pretty far away from the reach of the arm on either rover. And that has really been a very productive tool. I mean, it really has helped Curiosity do its job and will do the same on Perseverance, won't it?

Roger Wiens: Yeah. Mat, we've realized a long time ago, long before Curiosity launched, that if you can make a technique that is going to be easily usable out there, it's going to be used well and used a lot. And so, we set out to use something not typical in the laboratory but rather something that you could use without ever touching or driving up to a sample.

Roger Wiens: Seeing a demonstration of that way early on, it is said this kind of technique just has to fly to Mars and be used. And sure enough, it's been very, very useful that way. Because, you can imagine, for other sort of more typical laboratory techniques, you might have to polish the sample or get it to a certain size or whatever it is. We don't have to do that at all. We never touch the samples and we can analyze them all around the rover.

Roger Wiens: And so that's why that's the beauty of this kind of technique and we're really sold on this, and that's why we're doing SuperCam and we've got other ideas as well.

Mat Kaplan: How often has the work that ChemCam has done ended up with results that made the science team for Curiosity decide, "Yay, there's a rock over there. We weren't going to drive over there, but maybe we should because ChemCam has made it seemed pretty intriguing."

Roger Wiens: Yeah, that's happened a number of times, Mat. One very memorable time was when in 2015, Curiosity had just driven up a pretty steep incline. We got to a different area. We started shooting at some rocks in that vicinity and then we're going to drive on. It just so happened that there was a team meeting of the whole Curiosity science team and we were able to really talk about the results that we got and how different they were.

Roger Wiens: It turns out they were very high in silica like in opal for a mineral that was actually found there. And the rover team decided to turn the rover around. We stopped and we analyzed that whole area and that was an amazing discovery because there was a whole layer of this silica-rich mineral tridymite, which it turns out we have a lot of here in Los Alamos, New Mexico because we're on a mountain made of volcanic ash.

Roger Wiens: And that is what tridymite usually comes from. That suggests that there was probably some eruption that spread tridymite around in Gale lake when this was a lake there and that it's all settled to the bottom in one layer. And we just discovered that layer right there. But it told us what we think is a lot more information about volcanism on Mars. So there's a big story behind some of these discoveries.

Mat Kaplan: Nice work. Let's turn to some of those new capabilities that you have given SuperCam. I was surprised to see that SuperCam adds yet another laser to its arsenal.

Roger Wiens: Yeah, the laser actually has two different colors that we can use with a single laser.

Mat Kaplan: Oh, it's a single laser?

Roger Wiens: It is a single laser, yes. And so it does normally sort of its fundamental frequency is in the infrared at just over one micron. So, it's invisible to the human eye. We'd like to still show it as a red beam. But then, we can change the wavelength of that. We can double the frequency or half the wavelength. So, instead of 1,064 nanometers, it is then 532 nanometers which is smack in what we see as green color.

Roger Wiens: So that gives us the ability to use that laser for green, Raman spectroscopy, something that's quite well-known in the laboratory on Earth. We used it at a distance which is very different, of course, from the laboratory, and so we used some innovate techniques to allow us to do that including an optical intensifier that we pulled out of the assembly line for night vision goggles.

Roger Wiens: So that allows us to do this Raman spectroscopy not under the microscope or right up close, but up to a few meters away, just like we can do for the chemistry technique, the LIBS.

Mat Kaplan: That is fascinating. And something to do also with the fact that there are minerals that if you hit them with the right wavelength, the right color of light, they'll phosphoresce, they'll glow?

Roger Wiens: Yes, the Raman spectroscopy is actually an immediate response. So, while that laser is firing on the target and that's only for a few brief four nanoseconds, four billionths of a second, that rock lights up with not only green light coming back which is reflected laser light but a little bit of other light. We have to filter out the green light.

Roger Wiens: And so, we have two filters in our light path to get rid of about a factor of a million of that green laser light so we can see the other light because it's much, much dimmer. But what happens is, is that the molecules on the surface are effectively tickled or smacked a little bit but not quite as hard as the LIBS laser does. They're not blasted off. We don't make a pit in the target at all with the green laser.

Roger Wiens: But they're tickled, as I like to say, and they vibrate and the vibration actually causes the light to come back at slightly different wavelengths that are characteristic of the vibration frequency that those molecules are vibrating at. Depending on what the molecule is, what the end members are of those bonds, we can see the different wavelengths of those vibrations. Be they H and O like you have in water or C and O like you have in a carbonate rock or a silicon and oxygen like you have in a silicate.

Roger Wiens: And the relative masses of those atoms in the molecular bond give the different vibration frequencies which then give us wavelengths of light that we see coming out for that Raman spectroscopy. And so the Raman is instantaneous and then afterwards, we get an effect called fluorescence where materials that are excited go briefly to hire atomic excitation levels. And then sometimes, they stay there for a while and then they drop back down to a ground state or to a lower energy state and that's called phosphorescence or luminescence and that's a delayed effect.

Roger Wiens: And we can actually separate those because with that night vision goggle intensifier, we actually pulse it very rapidly and we can actually take exposures all the way down to a hundred nanoseconds, a hundred billionths of a second. And so, we can separate the instantaneous light that we get in the Raman effect from the phosphorescence or luminescence or fluorescence that we get from the minerals as they shine or glow later.

Roger Wiens: And that's really useful because that luminescence can be an interference on the Raman signals but we want to see them both. And so that way, we can separate them out with this shutter that's really highly adjustable to these very, very fast timescales.

Mat Kaplan: That's one heck of a fast shutter. At least a portion of what you're talking about, what I see when I go to a lot of natural history museums and you see minerals in a case lit in natural light. And then it will switch to an ultraviolet lamp and you see something completely different.

Roger Wiens: Yes, and that's a fluorescence effect. So that is what we see but like I was saying, the shutter that we use in our spectrometer can separate that from the Raman effect.

Mat Kaplan: Are there also things that SuperCam will be able to do without even needing to turn on the laser?

Roger Wiens: Yes. And so, one of the mineral techniques we have added is an infrared spectrometer. Actually, with ChemCam, we don't advertise it a lot but we have a visible range spectroscopy that we do and it has told us some interesting things about the oxidation state of iron in various places, in Gale crater. But a much more useful region of this passive color spectrum for looking at distinguishing things like carbonates and clay minerals is the near-infrared.

Roger Wiens: And so, SuperCam has a spectrometer that covers between 1.3 and 2.6 microns in range that's well above what we can see with our eyes but there are absorptions in that range. And so, if you had just looked at sunlight reflected off of rocks, in that infrared range, you can see the darker spectral regions where light is absorbed by, say, clay minerals or by carbonate minerals.

Roger Wiens: And so, we can distinguish them by looking in that spectral range. And that is our second mineralogy technique.

Mat Kaplan: You'll forgive me, I hope for a second, veil Star Trek reference but SuperCam more and more as you described it sounds like the visor that Commander Geordi used to wear on Star Trek Next Generation. That was a multispectral camera.

Roger Wiens: Cool, yeah. We've talked about the tricorder and so on, yes.

Mat Kaplan: Right.

Mat Kaplan: That's Roger Wiens. He'll return with more about SuperCam including its Mars microphone right after this break.

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Mat Kaplan: Let's turn to an entirely different kind of detection, something that as I said, The Planetary Society has dreamt about for decades. You know what I'm talking about. We tried it with the Mars Polar Lander-

Roger Wiens: The microphone.

Mat Kaplan: Yes, 1999. That didn't go so well. Nine years later, our next microphone made it to the Red Planet in one piece, was never activated because of fear that it could cause technical problems, interference with other electronics. So, now we're hoping, we're not behind this one the way we were the others, but we're sure hoping that this third time's a charm. Yes, we're talking about that microphone. Is it really a part of SuperCam or is it kind of an add-on?

Roger Wiens: We were selected for the mission, and then we started pushing for the microphone after that. We actually wanted to propose the microphone but we were thinking of doing it as an outreach part of the mission or a student project and it turns out that at that time, NASA didn't have a category or a place to do that within the proposal. So, once it was selected, then we started trying to get it back on.

Roger Wiens: We actually worked as a team to try to figure out what are the best purposes or scientific justifications for having a microphone on Mars. And, of course, we all know it's just going to be great to hear sounds on Mars, but we really want to know that this is going to be used scientifically. And in fact, it is.

Roger Wiens: Some of the studies that we've done were with the LIBS, the laser chemistry technique. I don't know if I spelled it out but it's laser induced breakdown spectroscopy that makes these little plasmas. They actually make a sound. It sounds to us a little bit like a zapping sound and it's-

Mat Kaplan: That's appropriate.

Roger Wiens: ... just a little bit ... Yeah, it is. It's not the laser itself that makes the sound, it's the sound of the laser ... What happens to the target and it's actually this little plasma. The plasma expands supersonically at the very beginning when it's very, very tiny and whenever you have supersonic transport, you actually have a sudden noise.

Roger Wiens: And so, it's the little zapping sound that we hear from these little plasmas. It turns out they've been studied for some time. They've been used to check whether your laser is in focus because it gets louder when the laser is in focus and when it's out of focus, things like that. So, we actually used it in the lab with ChemCam long ago.

Roger Wiens: So, now we're pursuing this dream to actually get it onto Mars and listen to the laser plasmas on Mars. The question is what's that going to tell us? Well, you can imagine, we're shooting at, say, two different rocks. And one of those rocks is hard. We shoot a burst of laser pulses and they all hit the surface and they don't really change the surface much. But if we're shooting at a soft rock, we're starting to make a little pit in that rock, and that pit gets deeper as we shoot more laser pulses.

Roger Wiens: Wouldn't you know if the sound actually changes between the first shot and the last shot when we have a little pit that we're making? And so, we can tell. We can use those differences to tell us whether the rock is soft or hard. It's not easy at all really to see the depth of that pit because we're looking straight on to it. Any albedo variations or color variations can be very tricky whether the sunlight is shining directly or something like that. And a little 100 micron pit doesn't really look like much in a dimpled rock.

Roger Wiens: Anyway, the sound is going to tell us whether the rocks are hard or soft and that's a very important physical property that's going to tell us quite a bit about the rock that we wouldn't know otherwise from the chemistry or mineralogy. It turns out that the microphone is also going to be useful for the environment on Mars. We can hear the wind and if you remember or think about walking outside on a windy day, when you're walking kind of straight into the wind, you get a lot of wind noise across your ears. But then when you're turned into or against the wind, you don't hear so much.

Roger Wiens: And we can use that same effect with the microphone on Mars. That microphone is mounted right on the mast, the box right next to the Cyclopes' eye of the rover, so it's way up there kind of hanging in the wind. And so, we'll be able to hear wind and be able to determine the wind speed and direction. We're not the only instrument to do that kind of thing. There's the meta instrument which is really dedicated to environmental measurements including wind.

Roger Wiens: But we'll be really curious to calibrate with them and see perhaps some different wind effects that we'll be able to tease out from this microphone.

Mat Kaplan: So, great science that will come out of this microphone, but you have to admit and it sounds like this is where you started, it's also just a lovely romantic notion to be sending something that will approximate to a human ear to the Red Planet?

Roger Wiens: That's right, Mat. And so, we're just curious what else we might hear. By the way, I've got a recording here of my voice through the microphone. Let me see if it comes up.

Mat Kaplan: Oh, sure.

Roger Wiens: This is the voice of Roger Wiens speaking to you through the Mars microphone on SuperCam.

Mat Kaplan: Okay.

Roger Wiens: And then I've got a sound of LIBS going with the microphone.

Mat Kaplan: Yeah, let's do all of this stuff.

Roger Wiens: Hey, everybody. I should say a little more about what you're about to hear. The first zaps are the sound of the SuperCam LIBS laser striking a target at normal atmospheric pressure on earth. Then you'll hear how it may sound in 1% of that, or the 6 millibar pressure on Mars. Now, because that's understandably muted, you'll then hear the Martian zaps amplified by a factor of eight. By the way, we thank ISAE-SUPAERO in France for these recordings.

Roger Wiens: What happens with the sound of that LIBS zapping sound is it's fairly a high pitch on earth but the high pitch frequencies on Mars are really attenuated strongly. The Mars atmosphere is very thin and it's carbon dioxide. The sound actually travels very slowly through that atmosphere and it's strongly attenuated but especially the high pitch sounds. Instead of the zapping, it sounds a little bit like you're just barely tapping a tom-tom drum. So, it's much lower in pitch.

Mat Kaplan: I suppose that not that it would be a good idea if you take your helmet off to try this, that if you were to try to let out a yell on Mars, call for your buddy across the way, it wouldn't carry very far because it is attenuated so much.

Roger Wiens: Yes. Everything is shifted and the lower tones are heard and the higher tones are not. We expect to hear the LIBS plasmas only to a distance of four meters or so. That's about 12 feet away.

Mat Kaplan: Not bad actually when you consider you're going to be doing this in only 1% of the atmospheric density here on earth. Before we go on, and I don't know how much you know about the other microphone that's being carried by Perseverance, but can you say anything about this other microphone that apparently may give us a soundtrack for a Perseverance's descent to the surface.

Roger Wiens: Yes. So, there is a microphone that you could say will be used before the SuperCam microphone, and that is the EDL mic. It's the Entry Descent and Landing microphone. So I think it is on a little camera that is on the port side of the rover, the left side of the rover kind of midway to the back. It is going to be recording what happens as this rover is descending through the atmosphere probably from time that the heat shield is dropped and the rover is parachuting down through the time that the retrorockets start up and through the time that the sky crane is lowering the rover by ropes onto the surface of Mars.

Roger Wiens: And so, I am excited to be able to listen to that microphone eventually. Who knows, maybe we can use that microphone with the SuperCam one to get some stereo sounds on Mars. I'm sure we'll be playing around.

Mat Kaplan: This gets cooler and cooler. The SuperCam is a great example of how international collaboration helps us explore the solar system. Can you take us kind of through its pedigree, because I saw that different portions of it come from various places around the world, beginning of course with where you are, the Los Alamos National Laboratory.

Roger Wiens: First of all, ChemCam was an international collaboration in which half of the instrument was built in France and funded by the French government. Half of it was built in the US and funded by the US and sponsored by NASA, saving the taxpayer half the cost in each country. And each country sort of claims it as its own and nobody fights over it. So, it's just a really great deal and we get to eat a little French cuisine from time to time.

Roger Wiens: When the idea of Mars 2020 rover was coming about, it turns out ... I was at an international conference where we were giving some of the first results of ChemCam and our first actual discussion about the SuperCam instrument was in a pub in Covent Gardens in London with our French colleagues. We went on from there to design SuperCam a lot like ChemCam. So, we used the same international French partners. Then, it came to deciding on a calibration target that would be on the back of the rover. The ChemCam calibration target, while people put a lot of work into it, it was almost an afterthought relative to the rest of the instrument. And we knew we wanted to do better on SuperCam.

Roger Wiens: And so, we asked our colleagues in Spain if they would be able to help supply a calibration target. They joined us, saving us from having more expense on our side. And so, now we have three nations that are involved in a fairly big way, but the targets that were actually used in that target assembly are coming from different places including different laboratories in France, in Denmark, in Canada, in Spain and in the US. And so, it's a truly international calibrations target set that we have on the back of the rover.

Mat Kaplan: I also saw that the sensor built into both ChemCam and SuperCam is from this company in the UK, Teledyne. But speaking of that calibration target, it kind of has interplanetary sources, doesn't it? Because I hear you are bringing a piece of Mars back home.

Roger Wiens: Yes. In fact, there are two instruments that are actually doing this trick. So, SHERLOC is also bringing a piece of a Martian meteorite back to Mars. So, both SHERLOC and SuperCam are doing that. Actually the Mars meteorite, we have all of these meteorites on the surface of the earth which have fallen to the earth. Most of them are from asteroids but my actual PhD work was involved in determining that some of these meteorites are not just from asteroids but a special few of them are from Mars. They got blasted off of the Red Planet's surface with a large meteor impact on that planet, flew through space for some time and landed on Earth.

Roger Wiens: Well, this particular meteorite piece that we have on the SuperCam calibration target was picked up in North Africa, in the North African desert where it looked very different from the desert sands. And it was identified as a Martian meteorite. It was actually sent to the space station for about a year, so it's already been out of the earth again. And then it came back to earth and then we mounted it on our calibration target assembly. And now it is back in space for the third time. This piece of rock is experiencing quite a ride.

Mat Kaplan: That is one well-traveled rock. I am glad you mentioned SHERLOC, the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals, which rates at least a nine on my NASA acronym creativity scale. As you said, LANL, Los Alamos National Labs, your colleagues there have had a big hand in creating this other instrument that's on its way to Mars?

Roger Wiens: Absolutely. So, in the sort of infancy or dream stage of what we were going to do, what we collectively, meaning the science community, was going to do for this rover, there was a team out at Jet Propulsion Laboratory including the ChemCam instrument engineer that is a very good friend of ours, Lauren Deflores. And she was now on this new instrument team and they were looking to figure out where they were going to get pieces of spacecraft hardware that had what we call heritage, that is, they've flown in space before. And so they're basically tried and true. Those kinds of pieces of hardware are very much preferred because we know they're going to work out there.

Roger Wiens: And so, she called us up and said, "Do you think we could adapt the ChemCam's sensor and electronics for this SHERLOC instrument concept that we have?" And we said, "Sure, we'll think about it." In fact, I've got a very good friend, Tony Nelson, who is our lead electrical engineer. And he is the guy who actually wizarded our way into the SHERLOC instrument. And so, Los Alamos built the detector portion and the electronics for it for the SHERLOC instrument. And so, we're very proud of that as well as SuperCam.

Mat Kaplan: As you should be. Some of your Los Alamos National Lab colleagues were my guests about a year ago. We talked about the lab's major contributions to space exploration that really are not all that well-known, especially compared to facilities like JPL and APL. You sure seemed to be building on this.

Roger Wiens: Yes. Of course, we are doing whatever we can and people here loved to work on space projects. Los Alamos has flown over 500 spacecraft instruments over the course of time. And so, we have a very large experience base and we're looking to build new things for the future as well.

Mat Kaplan: It's quite a record. And speaking of records, Roger, I'll leave you with this. There's something else I think I should congratulate you on. You talked about getting to enjoy French cuisine every now and then because of the partnership you have with CNES. You received a rare honor about four years ago. Should I really have been calling you Sir Roger?

Roger Wiens: Probably not. We don't usually use that. Thanks, Mat.

Mat Kaplan: But as I read it, the French Order of Palms chevalier which is the French knighthood, right?

Roger Wiens: That's correct. Yeah. And I'll say it, it was good for a fun party. Actually, the French have many parties in Paris, so that wasn't so special to them. But we were having a team meeting out in Pasadena, California for the Curiosity rover. And so, we arranged to have a big party at the French consulate in the Hollywood area. And so that was actually a very special thing for all of us because who gets to have a party in Hollywood at a large house over there? So, we had just a great time and it was great to spread the joy and have a lot of fun with all of the team members.

Mat Kaplan: Roger, how soon after its arrival on the Red Planet will SuperCam get to take its first shot quite literally at the Martian surface?

Roger Wiens: Mat, that of course will depend exactly on what happens or how the landing goes and all of the details right after that. If all goes as planned, we would start to ... Well, it's like arriving somewhere and having to unpack. You don't necessarily jump into the pool the moment you get to some place. You have to open your suitcase or bags and get out your swimming suit and so on.

Roger Wiens: And it's the same thing with the rover. We're just jumping for joy because rover has landed, but then we have a lot of things to do before we can do all the fun stuff. Some of the very first things are that the rover is commanding the spacecraft right now, and so we will have to change software from flight mode to landed mode. And so that will happen early on. Also, the mast of the rover is stowed down against the deck and that has to get deployed. Once that is deployed and we get the software for operating on the surface, then you can imagine the rover has to look around, make sure that when we command the laser to shoot at a certain place on the surface of Mars, that it is shooting there and not at the rover itself.

Roger Wiens: And so, all of those things have to get checked out. We're going to try to do that as quickly as we can, of course, but once those things are out of the way, then we're going to start zapping up the planet. You can be sure we'll be getting to that as quickly as we can.

Mat Kaplan: So much to look forward to. Roger, once again, congratulations. Best of success to you, the entire SuperCam and for that matter, Perseverance team. We will all be following along and I sure look forward to talking to you again about some of those results when they start to come back from SuperCam and that microphone that you brought along for the ride.

Roger Wiens: Well, thanks so much, Mat. It's such a great pleasure to talk with you and The Planetary Society anytime.

Mat Kaplan: Dr. Roger Wiens is a fellow at the Los Alamos National Laboratory in New Mexico where he is on the Planetary Exploration Team as he is for ChemCam aboard Curiosity. Roger is principal investigator for SuperCam, now on its way to Mars as part of the Perseverance rover. His 2013 book, Red Rover: Inside the Story of Robotic Space Exploration, from Genesis to the Mars Rover Curiosity, is still available, published by Basic Books. We'll put a link on this week's episode page at where you can learn a lot more about SuperCam and the Perseverance mission.

Mat Kaplan: Up next is our little visit every week with Bruce Betts. It will be What's Up.

Mat Kaplan: Time for a very special What's Up with Bruce Betts, the chief scientist of The Planetary Society. Why is it special? Because we're going to be reading some of the acronyms that many of you sent to us from Mastcam-Z. I think that makes it special, just like you.

Bruce Betts: Oh, you too, man.

Mat Kaplan: We're so special. How are you and what's up?

Bruce Betts: Honky dory swell planets. We got in the evening sky, Jupiter, Saturn over in the southeast but up in the early evening, Jupiter looking really, really bright. Saturn, to its lower left, looking yellowish. And Mars coming up now, not too long after those, and two hours later in the east. Mars, brightening as we grow closer to it in our orbits, we will get closest in early October but it is already almost as bright as the brightest star in the sky. Eventually, it will get brighter than Jupiter. It's going to be amazing, so keep your eye on Mars.

Bruce Betts: And in the pre-dawn over in the east, Venus just dominating super bright, it will be hanging out near the moon on the morning of the 15th. That is your sky report.

Mat Kaplan: Jupiter has been really bright. And so, if Mars is going to surpass that, well, I'm impressed.

Bruce Betts: And if Mat is impressed because he is, you're actually very easy to impress.

Mat Kaplan: That's true.

Bruce Betts: So, anyway, moving on this week in space history, this is impressive, Mat. 15 years ago, Mars Reconnaissance Orbiter launched, still doing great stuff at Mars.

Mat Kaplan: What a vet that one is. It's special.

Bruce Betts: Okay, you got me.

Mat Kaplan: I could tell.

Bruce Betts: Onto Random Space Fact, the height of the Perseverance rover's eyes, in other words, the Mastcam-Z cameras we talked about, is about the average height of a small forward in the National Basketball Association. Now, a small forward is a confusing term for those not following basketball since that equates to about two meters or a bit over six feet six inches.

Mat Kaplan: This is why I'm not a forward in the NBA.

Bruce Betts: Yeah, that's why.

Mat Kaplan: And they haven't put a camera on the mast on a rover at my eye height.

Bruce Betts: There are so many comments I shouldn't make right now.

Mat Kaplan: Thank you again because I'm special.

Bruce Betts: Yeah. Please stop, please stop. Okay, we move on to the trivia contest where I delve into theoretical, hypothetical acronyms. Thank you so much that so many of you came along with me on this very strange journey. The stereo camera on the mast of the Perseverance rover is a small forward named Mastcam-Z because it's mast mounted camera with zoom capability. So, I asked you to make up what every letter would stand for if Mastcam-Z were actually an acronym.

Mat Kaplan: I was very pleasantly surprised if not shocked by how many of these we got. Thank you all, fantastic work. And of course as usual, we don't have time to read everybody's but here are the runners up. I'll take Darren Ritchie's who said it from the state of Washington, which is special by the way, "Mat's Awesome Space Trivia Contest Autoreferential Message Zinger," he adds. "I know it's really Bruce Betts' awesome space trivia contest but bizarrely there's no B in Mastcam-Z, better blame Bell," Jim Bell, of course.

Bruce Betts: Definitely the cleverest kissing app now, if we gave them an award for that although there were other good kiss app ones too as well. This one tickled me, Ian Jackson from Germany, Magnificent Amazing Stupendous Tenacious Captivating Audacious Mars Zoomer.

Mat Kaplan: And you know what? You make it even better with that reading. That was great, not to say special. Here's one from Jessica Heckman in Switzerland. She says it's her first entry and she says, "Why not try? She's a space geek. She hopes to be a planetary scientist someday." Hey, good luck with that, Jessica. We're glad you're with us right now. Here is hers, Marvelous Atmospheric and Surface Target Camera to Analyze Mars Zealously. Great work, Jessica. Thank you.

Bruce Betts: I like that. It starts goofy, ends goofy and serious in the middle. It's kind of like an Oreo, I guess. Here's one from Mel Pall in California. Mat Always Says The Comments Are Missing, Zoinks.

Mat Kaplan: That little Scooby edition was nice, nice touch. Here's Maureen Benz in also the state of Washington. She actually submitted a couple and here's one anyway, Mars Ancient Samples Teach Children About Martian Zeitgeist. Very good, and of course, it will. We're ready now to go through our winners. And the first of these we both like, we're going to call it our realistic winner. Why, Bruce?

Bruce Betts: Well, despite tossing in an extra word or two, it's the one that to me sounded the most like it could be an actual acronym of NASA instrument.

Mat Kaplan: It comes to us from, congratulations, Jonathan [Gajewski 00:44:22] in Michigan, Mast Attached Stereoscopic Topographical Camera for Anisotropic ... I should let you do this one ... Anisotropic Mapping with Zoom. Sounds NASA to me.

Bruce Betts: You need to read it in a more formal way. The Mast Attached Stereoscopic Topographical Camera for Anisotropic Mapping with Zoom.

Mat Kaplan: Oh, that was marvelous. That was very special indeed. Jonathan, you will have your choice of that Planetary Society 40th anniversary T-shirt, the one that shows the positions of all kinds of bodies in our solar system on the day The Planetary Society was founded or, and it's your choice, the classic, the iconic Planetary Society caravel in space, our original logo of that ship in space. They're both pretty cool.

Mat Kaplan: Here is our other winner. We had a realistic winner. Here's the surrealistic winner. It comes to us from Thorsten Zimmer in Germany. And he submitted really several excellent ones, but here's the one that Bruce and I both liked the most, Might Actually See Turtles, Cockroaches and Martian Zebras.

Bruce Betts: What did you call that, the surrealistic winner? I think that was [crosstalk 00:45:42]

Mat Kaplan: Yeah, thank you. Thorsten, by the way, you'll have your choice of those T-shirts as well. Anybody wants to check them out,, or just

Mat Kaplan: Dave Fairchild, our poet laureate in Kansas, "Up there on Mars, Curiosity rover is searching for smack tights and other cool stuff. It has a camera that tracks where we travel and warns us of times when the surface gets rough. It has a name that is really an acronym, I know the secret but don't like to brag, Masterful Aperture Science Transmitter of Carefully Analyzed Martian Zigzags." Wonderful poem, the only problem, of course, is that it's not on Curiosity. It's on the upcoming Perseverance 2020 Mars rover. But nevertheless, great work, Dave.

Mat Kaplan: Again, thank you to all of you who took the trouble to come up with these and submit them to us this time. We're going to move on to another contest.

Bruce Betts: For something a little more concrete, what is the wavelength of the SuperCam laser you've been hearing about, SuperCam on the Perseverance rover? Go to

Mat Kaplan: Oh, and if you were listening carefully to this week's guest, Roger Wiens, you are ahead of the game, aren't you? All right, you have until the 19th, August 19th at 8:00 a.m. Pacific Time to get us this answer. And I goofed last week, I completely forgot. I mean, here we had Louis Friedman on the show, talking about his book. And I forgot that we have a copy to give away. So, we're going to do it this week.

Mat Kaplan: Planetary Adventures: From Moscow to Mars from Page Publishing, written by ... a reminiscences, a memoir from Bruce and my original boss at The Planetary Society anyway, Dr. Louis Friedman. All those great stories that we talked about last week, they're all in the book. And that's going to go to the winner of this new one. We'll award that in a couple of weeks. I think we're done.

Bruce Betts: All right, everybody, go out there. Look up at the night sky and think about your favorites Dawn fruit pit. Thank you, good night.

Mat Kaplan: Avocados, I can't eat them but I had the pit, the seed, what would you call it in that case with an avocado? It's amazing. It's special, one might even say. He's Bruce Betts. He's not happy now. He's the chief scientist of The Planetary Society who joins us every week here for What's Up.

Mat Kaplan: Planetary Radio is produced by The Planetary Society in Pasadena, California and is made possible by its members who are all ears. You'll do more than listen to our show and to become a member at Mark Hilverda is our associate producer, Josh Doyle composed our theme, which is arranged and performed by Peter Schlosser. Ad astra.