Next Week, A Return To Martian Soil

IRA FLATOW: This is Science Friday. I’m Ira Flatow. Next week, the Mars 2020 mission arrives at its destination. And if all goes as planned, the Perseverance rover will land on the red planet next Thursday.

Joining me now for a look ahead to the new rover mission and what it’s planning to do is Lori Glaze. She’s Director of NASA’s Science Mission Directorate’s Planetary Science Division in Washington, DC. Welcome to Science Friday, Dr. Glaze.

LORI GLAZE: Thank you. Glad to be here.

IRA FLATOW: Could you sum up for us this mission? What’s the main mission here?

LORI GLAZE: The key objectives of this mission, it’s a lander that’s going to land in a place called Jezero crater on Mars. I mean, it’s actually going to rove around. This will be our fifth rover on the surface of Mars.

And the primary objective is to understand the geology in that location, understanding the geologic history of Jezero crater, but also really looking at the astrobiology history at that location, where astrobiology is the science of understanding what types of environments can support life and actually looking for potential chemical markers of early microbes that may have existed 3 and 1/2 billion years ago. And then the third major objective is to collect samples of rocks and soils and store them on the surface for eventual return back to Earth. And then finally, it also has a goal to help us better prepare for eventual future human exploration of Mars.

IRA FLATOW: So let’s see if we can unpack some of this, because there are a lot of interesting mission objectives here. The landing site, is there something special about this site that would help you accomplish what you want to do there?

LORI GLAZE: Yes there is something special. So we are landing in Jezero crater. There were lots of potential great landing sites on Mars with lots of great science questions that could be answered. But this particular landing site was intriguing, because we can tell by looking at orbital images of the surface of Mars and looking at Jezero crater that there was a river that once flowed into this crater and that there must have been a standing body of water that persisted for a very, very long time.

Because we can see that as that river flowed into the standing body of water that it dropped sediments onto the ground, onto the floor of the lake, and created a river delta right in there inside the crater. And we also know that that crater and this river delta system would have been active about 3 and 1/2 billion years ago. That’s about the time that life was starting to form on Earth. And we know that Mars was much warmer and wetter, as evidenced by the rivers and lake, and that had life started to form on Mars at that same time, this would be exactly the kind of deposit that would preserve those really early microbiologic fossils in the river delta.

In addition, because it’s a river delta, the river would have been picking up sediment from a huge catchment area and then delivering it all into this more or less confined spot right in Jezero crater. So as we’re thinking about trying to address questions about the early evolution of Mars and understanding whether or not life ever existed on Mars, this is the ideal place, or one of the most ideal places, on Mars that we can visit.

IRA FLATOW: So this would have been a catch basin for any kinds of life forms that once lived there?

LORI GLAZE: Exactly so.

IRA FLATOW: What kinds of experiments do you have on board?

LORI GLAZE: Several of the instruments are really designed for this understanding the geology and the astrobiology history. We have SHERLOC, which is an instrument to help us better understand the organic chemistry that’s present. We also have PIXL, which is an X-ray instrument that also is looking at chemistry of the surface. And then we also have another instrument called SuperCam, which is, again, another remote instrument that shoots rocks with a laser to help us better understand what chemistry is present.

So those three instruments, as a package, are doing a lot of work trying to understand the chemistry and mineralogy of the rocks. We have another instrument called RIMFAX. It’s a ground penetrating radar to understand the structure of the crust just beneath the rover. We also are carrying a whole bunch of camera systems that are going to be able to do panoramic images and stereo images for context to help us both with navigation, but also to understand what we’re looking at.

We have a meteorological station that will be taking regular measurements of temperatures, and pressures, and winds on the surface. We actually have microphones that will help us hear what’s happening on the surface of Mars for the first time. And then we also are carrying a really cool experiment called MOXIE, which is a technology demonstration to actually convert the carbon dioxide of Mars’s atmosphere and convert that into breathable oxygen. And this is an experiment that’s being sponsored by human exploration to help us better prepare to explore Mars with humans and take advantage of the resources that can be found there in situ.

IRA FLATOW: Will Perseverance be able to look at a rock sample and say, hey, this has a greater chance of having life, let me pick that one up versus the one next to it?

LORI GLAZE: The Perseverance rover has a fantastic suite of really amazing instruments that will be able to look at the rocks and tell us what the chemistry of those rocks is, what the minerals are that are present in those rocks. And we’ll be looking for those kind of chemical markers, molecules and minerals that contain carbon, hydrogen, oxygen, nitrogen, those key building blocks to life. Answering the question of whether or not life is there or was there in the past, doing that remotely is very, very challenging. So that’s why those instruments will help us identify, as you said, the right samples that we really want to drill and store for return back to Earth.

IRA FLATOW: How will those samples the rover collects make the return trip to Earth?

LORI GLAZE: That is a great question, and one that we are really excited that we are starting to embark on right now is the Mars sample-return mission. This is a really complex endeavor and one that we are not going to take a loan, as NASA. We’re actually partnering very closely with the European Space Agency in our early development and planning for Mars sample return.

We just started what we call phase A, which is the very beginnings of those plannings. We’re working towards a launch in 2026. And what that mission will look like, it will actually include two launches from Earth, a NASA launch, which would carry a sample return lander to the surface of Mars. And that lander would carry a fetch rover that would drive out and collect the samples that Perseverance has picked special locations to drop a bunch of the sample tubes at these caching locations.

So the fetch rover would go to those specific locations and pick up those tubes at maybe several of those cache depots, and then carry them back to the sample return lander, load them into a return capsule that’s then launched from the surface of Mars on the Mars ascent vehicle, and place that capsule into orbit around Mars. The European launch, meantime, has sent an orbiter that is in orbit around Mars and will rendezvous with that sample container and capture that sample container to bring it back to Earth.

IRA FLATOW: Wow. Sounds like a terrific idea, very complex mission. Let’s talk about a test helicopter that you have on board, something totally different.

LORI GLAZE: It is totally different. This helicopter will be the first-ever powered flight on another world. And we are really, really excited about this technology demonstration. It’s not something that’s required for Perseverance’s success, but it is a truly enabling technology that, if we can demonstrate the ability to have powered controlled flight on Mars, this would change the way that we are able to explore the surface of Mars. So it is a helicopter, a rotorcraft, very small, and it will be demonstrated in the first few months while we’re on the surface of Mars.

IRA FLATOW: And does it look like a helicopter we might see right here on Earth?

LORI GLAZE: It kind of looks like a small drone. It’s a little box. It’s got two pairs of rotating rotors. It’s got four little legs on it that help it to land gently. I think it would be recognizable as a helicopter.

IRA FLATOW: Yeah. How does Perseverance fit into the big picture of other Mars missions? You’ve had Curiosity, Insight. We’ve had a succession of very successful missions. How does that complete what they’ve done?

LORI GLAZE: So Perseverance really is the culmination of what we’ve learned with all of our exploring to date. Every mission that we send to Mars answers questions, but asks new questions. And we keep building on what we’ve learned on each one of those missions.

So in the earliest times, we sent Viking, of course, to the surface of Mars. In a sense, it was designed, we thought, to look for signs of life. But as we look back on that experiment now, those experiments that were held on Viking, we didn’t know enough about what we didn’t know. Even if life had been there, those experiments probably would not have been successful. But then we learned from that, and we learned about the need to really understand the environments where we were going so that we could design the right experiments.

Spirit and Opportunity rovers were able to identify and conclude that there was actually some water present in the past. It wasn’t clear whether that water was really the right acidic or pH level to support life as we know it. But then we sent the Phoenix lander, which actually found water ice on the surface of Mars, confirming that there is water ice present on Mars.

And then the Curiosity rover and Gale crater was able to confirm that not only was there standing water for a persistent time in Gale crater, but that water was a pH level that could support life. And then Curiosity also found these complex organic molecules, another building block for life. And so each of those helped us to better understand what kind of environments we need to be looking for and how to design our experiments. And one of the big lessons learned there is that, really, bringing the samples back to Earth is the key piece that we need to really understand what we’re seeing in the rocks on Mars. And so that’s one of the fundamental elements of Perseverance.

IRA FLATOW: You, meaning NASA, has had such great success with the longevity of its rovers. What, the first rovers were supposed to last 90 days, and then decades later still working. What is the life expectancy of this one?

LORI GLAZE: That’s a really great question. And you’re right, I mean, the Spirit and Opportunity rovers were, oh my goodness, the Energizer bunnies. They just wouldn’t stop going. And then finally, of course,

Opportunity was overcome by a dust storm, by all things. The rover was still going strong, but the dust storm finally took it out. We couldn’t recharge the batteries with the solar arrays any longer.

Now, Curiosity is still going strong as well. But both Curiosity and the Perseverance rover have different power systems than those early Spirit and Opportunity rovers. Spirit and Opportunity had solar arrays that powered them, required the sun. Curiosity and Perseverance, of course, have nuclear power sources, which means we’re not susceptible to dust storms impacting our power, which is great.

But the downside of that, of course, is that a nuclear power source does have a limited lifetime. Eventually, the nuclear source will decay sufficiently that we won’t have enough power to do our work. But as we’ve seen with Curiosity, it’s already been on the surface of Mars what, I think about eight years now, and still going strong, expected to continue going strong for a few more years. And we expect Perseverance to have a similar lifetime capability. The primary mission is just one Mars year, which is two Earth years, but we fully expect it to be operational well beyond that.

IRA FLATOW: Just a quick reminder, this is Science Friday from WNYC Studios. In case you’re just joining us, I’m talking with Dr. Lori Glaze, Director of the Planetary Science Division in NASA’s Science Mission Directorate, talking with her about the upcoming lander of the Perseverance rover on Mars. What should we expect to see next week? How will the landing take place? Walk us through the sequence.

LORI GLAZE: OK. The landing is an incredibly exciting experience. It puts you on pins and needles. It’s often called the seven minutes of terror, because landing on Mars is really a complex operation, where the spacecraft comes in well over 10,000 miles an hour as it hits the top of the atmosphere, and then within seven minutes it needs to completely autonomously slow down and land softly on the surface.

And that sequence this time is really going to demonstrate a couple of new things, a couple of new technologies that are enabling us to actually even land in Jezero. Jezero is a much smaller target than we’ve ever tried to hit before. And so as we come in to the top of the atmosphere and then we take a look and identify where we are, and that helps us to pinpoint exactly the timing of that parachute release to help us begin that vertical drop in the right location.

And then as we get closer to the surface, we have what we call terrain relative navigation, which is an imaging system taking images of the surface and in real time comparing those against maps that we have that identify the safer places to go and the riskier places to go and as we’re coming down, can quickly identify what’s the safest place within our reach to land and then maneuver over to that location before the sky crane lowers the lander down to the surface. So a really exciting chain of events, really encourage folks to watch it. This is a step up from what we did with Curiosity. But we learned a lot from Curiosity, and we think we’re definitely prepared.

IRA FLATOW: I didn’t really realize there was something different going on in the sky crane part of this.

LORI GLAZE: Yeah. We could not have landed in Jezero with Curiosity. The landing ellipse was too large. But there was so much exciting science that the engineers put their thinking caps on and came up with these really clever additional technologies that we can allow us to pinpoint our landing, which is actually another feed forward to human exploration.

IRA FLATOW: You say this is going to be a very busy time, but there are missions from the United Arab Emirates and China arriving around the same time. Nothing like this has ever happened before.

LORI GLAZE: That is correct. This has never happened before. We do have, of course, partners already in orbit at Mars. The European Space Agency and Indian Space Research Organization have orbiters at Mars. But this will be, I think, the first time that we have three different countries arriving at Mars almost at the same time.

We all launched back in the summer, and we’re all arriving approximately the same time in February. Yes, United Arab Emirates arriving on February 9, and then closely followed by China with their orbiter arriving on February 10. And then Perseverance arriving on the 18th. I think it’s an amazing time for Mars science to have this much interest and this much international participation in the global science.

IRA FLATOW: Well, we all wish you great luck, everybody who’s involved in the project and everybody in the world watching this. Thank you, Dr. Glaze, for taking time to be with us today.

LORI GLAZE: It’s my absolute pleasure Thank you.

IRA FLATOW: Dr. Lori Glaze, Director of NASA’s Science Mission Directorate’s Planetary Science Division in Washington, DC.

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