NASA Podcasts

NASA EDGE: MSL Curiosity Landing
10.09.12
 
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NASA EDGE: MSL Curiosity Landing
Transcript

Featuring
Live coverage of the MSL Landing
- Monica Grady
- Lou Mayo
- Ian Hutchinson
- Lewis Dartnell

[Music]

ANNOUNCER: Its journey through space is over. NASA's Mars Science Laboratory is ready to take planetary science to a whole new level. Curiosity is fully operational on the surface of Mars. Discover how NASA’s latest rover will explore this next great scientific frontier.

[Music]

CHRIS: Welcome to NASA EDGE.

FRANKLIN: An inside and outside look...

BLAIR: … at all things NASA.

CHRIS: We’re here live in the piazza at Media City, UK in Salford.

BLAIR: Yes, and we’re also live on twenty-two screens around the United Kingdom, thanks to the BBC. Welcome everyone to our live coverage of the MSL landing.

FRANKLIN: We’d like to thank all of the people who have come out here to Media City, UK, who woke up early with us to join us on our broadcast this morning.

BLAIR: Free breakfast.

[Clapping]

FRANKLIN: Free breakfast.

CHRIS: This is such a great event.

BLAIR: Absolutely.

CHRIS: In about a half hour or so, Curiosity will be landing on Mars; a very historic occasion. Also, besides talking about MSL and the Mars rover, Curiosity, we’re also going to be talking about ExoMars a little bit later in the broadcast.

BLAIR: We’ll also be going back and forth to JPL as things unfold and develop throughout the course of events today. They are providing obvious coverage at Mission Control. We want to keep apprised of that, keep up to date as things are going.

CHRIS: It’s traveling over 8,000 mph right now.

BLAIR: It’s Olympic speed.

CHRIS: Faster than Usain Bolt.

BLAIR: Yes, something like 300 times faster than Usain Bolt did yesterday in the 100-meters.

BLAIR: I’m sorry. I’m a bit distracted because you’re holding a piece of Mars. Tell us about this piece of Mars.

MONICA: It’s a bit of meteorite that has come from Mars. So, we already have Mars rocks. These come to Earth when an asteroid hits the surface of Mars and breaks bits off and they just fall completely at random on Earth. We know they’re from Mars...

BLAIR: That was going to be my next question. She could see if forming in my head.

MONICA: I know it’s from Mars because it’s got gas trapped in it. When you heat up the rock you get the gas out and the gas has got the same composition as Mars’ atmosphere. It’s got carbon dioxide and argon and other things, which are exactly the same as Mars’ atmosphere. It was a real detective story.

BLAIR: I was going to say it sounds like a detective situation. It’s almost like you’re looking for Mars’ fingerprints, and that’s found by gases, huh?

MONICA: Yep, that’s absolutely right. If we look at the Earth and think about the Earth, and what’s in its atmosphere, we know it’s about 4/5 nitrogen and about 1/5 oxygen. That’s how we can live here. The pressure of the atmosphere is 1,000 millibars. We know that from the weather forecasts and stuff like that. But on Mars, it’s very different. It’s only 6 millibars; so .006 of the pressure of Earth’s atmosphere. It’s practically all carbon dioxide. Nobody could stand on the surface of Mars and live there. A human couldn’t.

BLAIR: Now, that’s got to be rare. You’re holding a very rare artifact. I’m nervous being in this proximity to something so valuable.

MONICA: Are you talking about me, or the rock?

BLAIR: Both.

[Laughing]

FRANKLIN: I’m here with Hugh Perryman from Manchester. What’s your question, Hugh?

HUGH: What is the significance of the Gale Crater where it’s landing?

LOU: Well, of course, the selection of the landing site was critical. They came up with a number of great, potential candidates and Gale Crater won out. Gale Crater is south of the Martian equator and it’s a very low-altitude crater. It has some very interesting properties. While being low altitude, water runs down hill. So, perhaps there’s a chance that water once stood in Gale Crater. We believe there are clays on the base of the crater and there’s a large mountain that looks like it’s made of different sediments right in the middle of the crater. It’s a fascinating place to explore.

CHRIS: We have a question here from Twitter. Why isn’t MSL using airbags like other missions?

LOU: It’s difficult to go to Mars and we’ve had a few failures. It was thought that using airbags to cover the rovers we send to Mars, and kind of let them bounce until they settle on the surface of Mars was a pretty low risk, pretty good idea, pretty good way to send rovers to Mars. But Curiosity is just too big. This thing weighs a metric ton and it’s too big to put bags around. So, they’ve adopted this very intricate method of landing with many multiple steps that occur automatically and must occur in proper order and proper sequence for it to make it to the ground.

CHRIS: We’re going to go back to the actual animation of MSL as it enters the Martian atmosphere.

BLAIR: This theoretically happened minutes ago on Mars in the Martian atmosphere.

CHRIS: You see what happens is with that 14-minute delay…. Are we really here or is it 14 minutes past or in the future?

[Franklin laughing]

BLAIR: Don’t get me on time travel. I’ll get wrapped around the axle and it will be bad news for everybody.

FRANKLIN: No, we don’t want to do that.

CHRIS: We have the guidance navigation control. It’s steering the spacecraft entering the Martian atmosphere.

BLAIR: Interestingly enough, MEDLI is actually getting important engineering data from the entry.

CHRIS: Yeah, this is the first time we’re actually going to be getting important scientific data inside the heat shield and going to be studying about the Mars’ atmosphere.

FRANKLIN: Those measurements are being taken through MEDLI until the heat shield is discarded.

BLAIR: Any time now.

CHRIS: Then with the parachute, it slows it down to below super sonic speed with the largest parachute ever to be used on a planetary surface.

FRANKLIN: It weighs just about 100 pounds.

CHRIS: Once we collect all that data from the MEDLI instrument, which stands for Mars Science Laboratory, MSL, Entry, Descent and Landing Instrumentation Unit. That data is going to be transferred to the rover and then the heat shield jettisons.

BLAIR: Yep. And then, of course, a very dramatic, probably one of the most complex things designed for this mission is the Sky Crane. Which we’ve never done anything like this, ever. Actually, deploying a rover from a hovering Sky Crane.

FRANKLIN: Looking at this, this is the type of stuff sci-fi movies are made of.

BLAIR: That’s right.

FRANKLIN: When you look at this animation, it’s mind blowing.

CHRIS: It’s pretty Star Wars.

BLAIR: Yeah, Jawas are feasting on this. They’re ready to take this into their sandcrawler.

CHRIS: But it’s just hard to fathom we’re looking at essentially a mini cooper falling down to the surface of Mars.

BLAIR: Falling? Sky Craning down.

CHRIS: Yes, Sky Craning down.

[Music]

MISSION CONTROL: Touchdown confirmed. We’re safe on Mars.

[Cheering]

CHRIS: Touchdown confirmed! All right.

[Franklin and Blair laughing]

CHRIS: Yes! Look at that!

BLAIR: Oh, awesome!

CHRIS: Live from Media City, UK in Salford, we have touchdown.

[cheering]

BLAIR: Across the United Kingdom, people are seeing the joyous reactions of the team out of JPL, all around NASA. It looks like we have had a successful landing of Curiosity.

[Cheering]

CHRIS: Wow.

BLAIR: Let the science begin.

CHRIS: This first image we get is going to be a very low-resolution black and white image. It may be very difficult to see on screen if it comes through. That’s coming from one of the cameras onboard Curiosity.

FRANKLIN: I’m just looking at these pictures and saying to myself, “It worked, that Sky Crane.”

CHRIS: And for those of you out in the crowd on the piazza, what do you guys think?

[Cheering & clapping]

BLAIR: Years from now, when we’re landing on Mars, you can tell all your family where you were the day Curiosity landed and made that possible, paved the way for that to happen.

BLAIR: It’s great to see the enthusiasm of everyone out at JPL. Now we’re beginning a new era of massive science coming from the surface of Mars.

CHRIS: Absolutely, and over the course of the next several days and weeks, they’re going to be turning on the instruments, getting a lot of feedback from Curiosity. We’ll begin the journey. Remember it’s not a sprint. We have the Olympics going on and if you really want to pick an event, I would say it’s a marathon because it’s going to be a two year mission, minimum. Curiosity is in it for the long haul.

FRANKLIN: But to pick another event, gymnastics; we can absolutely say that Curiosity stuck the landing.

BLAIR: Absolutely.

CHRIS: That was a perfect 10, wasn’t it?

FRANKLIN: Yes, perfect 10.

FRANKLIN: I’m here with Kate from Manchester. What’s your question, Kate?

KATE: I’d like to know how long the power source stays live?

CHRIS: Very good question.

LOU: It’s an outstanding question. We had one set of landers on Mars, the Viking Landers that used a nuclear power source back in the 1970s. Since then, we’ve been using solar cells but the Curiosity rover has a plutonium nuclear power source. That power source is going to last for about one Martian year, which is about two Earth years.

CHRIS: Now that’s called on the technical terms, RTG, or radioisotope.

CHRIS & LOU: thermoelectric generator.

LOU: I like that word. We can say that again.

CHRIS: RTG, say it again.

LOU: Say that ten times.

CHRIS: Yes, yes. For Spirit and Opportunity back in early 2000s, it was only designed to last three months. We still have Opportunity still going now.

LOU: That’s right. That’s been a wonderful addition to that mission. Spirit and Opportunity are using solar cells. So the thought was that Mars is a dusty environment. Dust would build up on the solar cells and make them not very useful after awhile but it looks like that dust is being swept off the cells by perhaps little Dust Devils or other atmospheric winds. They’ve been able to operate quite some time.

CHRIS: The great thing about having a RTG on Curiosity is the fact that the power source will out live much of all the actuators, the engineering mechanisms on the rover. They’ll probably go first before the actual power source.

LOU: Uh, hard to say. We’ve designed missions in the past for a finite lifetime and they’ve lasted well beyond their design specs, a good example of that is Voyager. Voyager missions were initially targeted just to go to Jupiter and Saturn. They said, well, let’s go onto Uranus and Neptune with Voyager II. And now it’s an interstellar mission breaking through the heliopause and moving off into deep space.

FRANKLIN: Quick question: What is the temperature on the dark side of Mars?

LOU: Well, Mars, like the Earth, has an atmosphere. It’s a thin atmosphere but it has an atmosphere to spread heat, and it rotates just like the Earth does. In fact, its day isn’t that much longer than an Earth day. Nighttime temperatures get down to -100 Centigrade, -120 Centigrade, something like that. It’s awfully, awfully cold. It’s an interesting plant because it’s so much like Earth in so many ways and it’s so different from Earth in so many ways.

CHRIS: That is one of the questions we had. It says, “How is Mars like Earth?” There you go.

LOU: Okay. Let’s see. Mars is a terrestrial planet. It’s got a hard surface like Mercury, Venus… Mercury, Venus, Earth and Mars are the terrestrial planets. They all have hard surfaces. They’re relatively small. They’re relatively dense, something on the order of 5 grams per cubic centimeter; all about the same density. They all have atmospheres, Mercury, not so much, but a little bit. And they’re all relatively near the sun. Mars is about half the size of Earth. It has evidence of volcanism. It has the tallest mountain in the world, Olympus Mons, an extinct volcano in the Tharsis region. It has polar caps like the Earth does but unlike Earth, it’s polar caps are both water, ice, and carbon dioxide ice. It has evidence of water flows and probably oceans maybe in the northern hemisphere. A long time ago, in its early formation, Mars once had a magnetic field like the Earth does but it looks like it lost that field. That opened its atmosphere up to erosion by the solar wind, and that, and other processes, collisions from space and so on, resulted in a much thinner atmosphere, and a much colder surface. Those are some of the ways that Mars is like Earth and different from the Earth.

CHRIS: Will Curiosity be analyzing rocks and soil?

LOU: Oh, absolutely. That’s one of its primary functions on Mars. It is a geology laboratory sitting there doing all of this analysis, a lot of it automatically. It’s going to be able to come up close to a rock, just like the MER rovers and analyze the rock that way. It can look at rocks from far back. It can scoop up soil and put it in analysis containers for spectroscopy to tell what minerals are in the soil. Is there water? Are there water-bearing compounds? Is there organic life in the soil that might link to possibilities for life, that kind of thing.

CHRIS: This particular rover is not detecting life. It’s detecting the habitability of maybe once life existed or still exists.

LOU: That’s exactly right. Could life have lived in an environment like Mars in the past? Are the habitable areas currently? Maybe under the surface, can we find water? In other words, evidence of habitability, that’s what it’s really looking for.

CHRIS: Because ultimately, I think the big question for our viewing audience, even here in the piazza, is there life on Mars? I think everyone wants to know that question. Hopefully one day we’ll be able to answer that.

LOU: That’s right. Maybe ExoMars will help us, as well as in future missions.

BLAIR: Let’s talk about ExoMars. That’s the mission you guys are working for to go to Mars. Tell me, what is ExoMars?

IAN: ExoMars is a mission that’s formed from two parts. Firstly, there will be an orbiter this June to go up in 2016. That will also be used as a data relay for the rover which will be launched in 2018.

BLAIR: Is that similar to Odyssey? How Odyssey helped us complete communication.

IAN: That’s absolutely right.

BLAIR: And so that will deploy and then ExoMars has a rover as well.

IAN: That’s right. The 2016 mission, first though, needs to demonstrate the entry, descent, and landing system. It’s a practice if you like, for the rover itself. And then, once we’ve got all the data back from instruments on there, we’ll be able to verify the final performance of the rover descent, and then hopefully we get all the data back from the instruments from that rover as well.

BLAIR: I’m very curious, what does Exo stand for?

LEWIS: I think the reason they’ve called it ExoMars is because this rover is an astrobiological mission. So, what Curiosity will be able to tell us how habitable Mars has been in the past, whether it was ever appropriate for life. The next step after which is what the European Space Agency, the ESA mission, ExoMars will be able to do; is to tell us know if there are actual signs of life on the surface of Mars. This field of science called astrobiology or exobiology, so it’s the ExoMars mission.

BLAIR: So, when you’re watching the good news of Curiosity come back, you’re happy not just for the success but you’re actually going to be able to use that data to help your future missions.

LEWIS: Exactly. We’re both very, very excited about this mission and the science it is going to send back. We’ve seen what the engineers have been able to pull off with that incredible entry and descent landing, the EDL. And now, it’s kind of handing the baton onto scientists to start doing these experiments and using all these incredible instruments to find out as much as we can about Mars.

BLAIR: Obviously we’ve talked about MSL and Curiosity going to Gale Crater. And obviously, they’ll be sending that data back based on that region. Will you look for a similar region or will you deliberately look for a different region of study?

LEWIS: We’ll be looking for a similar region. The reason we went to Gale Crater with Curiosity is because as far as we can tell from orbit, it was a wet place; an ancient, primordial Mars. We think there was a lot of liquid water lying down these minerals, and, in fact, clays. There seems to be a lot of clays right in the base of this great big mountain in the middle of this crater, Gale Crater. On Earth, clays are only laid down in standing water. Life needs water, so it’s a signature for a habitable environment that might have been there on primordial Mars. With ExoMars we want to go to a very similar environment. We want to find places where it seems to be a warm, wet environment and then see if anything ever did get started there.

BLAIR: Wow. Are there a lot of candidates like that? Have you identified them? Where are you guys in the process for picking a landing site?

LEWIS: I think we’ll probably use some of the short list that was drawn up for Curiosity. We’ve now mapped to a very, very small scale a great deal of the surface of Mars. We know what its geography is like. We’ve identified some of the most promising candidate sites. And Curiosity has gone to one of these most promising. And depending on what it finds, we might go to Gale Crater as well with ExoMars. We might go somewhere else. We might do a follow up mission, kind of land along side it perhaps.

BLAIR: Can you imagine the tag team mission in Gale Crater?

LEWIS: High five on the surface of the two rovers.

BLAIR: That’d be fantastic. Obviously, you’ve make that decision not on the cool factor of being in close proximity but based on how rich the area is for the science.

LEWIS: Exactly. Yeah.

IAN: Another key point to make about the ExoMars’ mission is that the rover will carry a drill. An exciting point is it will be able to go down into the subsurface and extract samples for investigation.

LEWIS: Because Mars doesn’t have a magnetic field like the Earth does and as we’ve already seen it has a very thin atmosphere. There’s a lot of space radiation beating down onto the surface of Mars. This will break up any organic molecules, any signs of life that might remain there. What we really want to do is get down beneath that surface layer that is being degraded and destroyed. This ExoMars drill is about two meters long.

BLAIR: Wow.

IAN: It’s a good arm’s length, in fact, longer than my arm, delving right down through the surface grabbing a handful of Martian soil and bringing that dirt back up to the surface to analyze and test, and then find something that might have survived a bit deeper.

CHRIS: Lewis, you have a couple of…

LEWIS: Things on my knee.

CHRIS: … pieces of rock on your leg. And something is growing there it looks like.

LEWIS: Yes. One of the earlier questions was what preparation can you do before you go to Mars? Obviously, one of the things you want to do is test your equipment, your instruments before you launch it to the Red Planet. The samples I’ve got here are from Mars analog sites. They are samples of rock from some of the most Mars like places on Earth, so we can study what the rocks there are like or their survival mechanisms of organisms. On this rock, if I hold it up like that you should be able to see, this is some a hard, granite type rock.

CHRIS: Is that microbes growing on there?

LEWIS: These are lichens. These crustaceans, these bright orange crustaceans you can see here are lichen. They’re actually an advanced life form. This is an obvious thing to see with your eye but we wouldn’t actually expect anything as advanced and complex as this sort of lichen, this multi-centered life that we have on this rock. What we’re hoping to find; it does look a bit more boring, if you can see right on the inside edge of this rock. You’re looking at the side of the rock where it’s broken open.

CHRIS: Okay.

LEWIS: Just under the surface, if you squint, you might be able to convince yourself you can see a thin band of green. It’s the green of chlorophyll, the molecule that allows plants and trees to photosynthesize and grow by sunlight. And there are microscopic cyanobacteria cells that have grown inside the rock themselves to protect themselves from the outside environment and tinting it just green. What we would do with ExoMars is use much more sensitive equipment than just our eyes to analyze inside rocks like this by grinding them up and see what bio signatures or what signs of life we can find inside.

CHRIS: You’re working on an instrument for ExoMars called the Raman instrument?

IAN: That’s right. It’s a Raman Spectrometer, a lasar spectrometer that forms part of the analytical laboratory. There are several instruments on ExoMars itself. There’s an instrument on the drill which illuminates the hole which the sample is extracted from and gets some initial information on the environment that the sample has been in. And then there are several other instruments that take images and look at the sample itself and does this before it gets crushed into powder, and then passed to the analytical instrumentation. The Raman Spectrometer is one of those. It incorporates a laser. You shine the laser onto the sample and then the light that comes back give you information on the molecular composition. So, you can determine what the sample is made from and hopefully detect any bio signatures or signatures that indicate the presence of past or present life.

CHRIS: From my understanding, this rover will be about the size of Spirit and Opportunity?

IAN: That’s right.

CHRIS: Okay. And it’s using solar power?

IAN: Yeah. You can imagine all the technical challenges here getting the drill in place to extract the sample, then to crush it without any thing getting jammed, and then to pass it around to all the individual instruments and get results from each one of those.

CHRIS: That’s a good point. Coming back and looking at this drill, you want to be able to take a core sample. The ground has to soft enough. You don’t want to land on a surface where it’s going to be so hard to drill 1 to 2 meters deep. You take that into consideration when you’re looking at the landing sites.

LEWIS: Yeah, absolutely.

IAN: Selection of the landing site and the rover also incorporates the radar instrument called WISDOM. They collect, use all the different data from instruments to determine an appropriate place to look for samples.

CHRIS: I think it would be kind of cool if you had some of these rovers actually meeting up one day.

LEWIS: One of the plans for ExoMars was to land as a twin mission; to have two rovers land at the same site and doing tag team science having different instruments on board to build up the story together; collaborate.

IAN: You can imagine the engineers’ response to that kind of suggestion.

CHRIS: That’s a good point.

LEWIS: They will collide in midair.

CHRIS: It goes back to the scientists and engineers working hand in hand.

LEWIS: Yeah.

CHRIS: We want to thank everyone who came out here today to help us celebrate the arrival of Curiosity on Mars. Thank you to the mayor, the city of Salford, Media City, UK, the BBC, everyone who made this webcast possible. You are watching NASA EDGE.

BLAIR: An inside and outside look…

FRANKLIN: …at all things Curiosity.

BLAIR: You even folded that in there.

CHRIS: Have a great day.

BLAIR: That’s nice.



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