NASA Considers Cheaper, Faster Ways To Retrieve Mars Samples

IRA FLATOW: This is Science Friday. I’m Ira Flatow. In case you missed the news, I’m welcoming Flora Lichtman on board as a host. Yes, we’ll be working side by side to continue bringing you the fun, the thought-provoking, and even the weird science stories.

FLORA LICHTMAN: Thank you. Ira Yes. Excited to bring the weird and excited to be here. Later in the hour, what you need to know about the bird flu outbreak. The US just reported its first death from the virus. How worried should we be? And artificial general intelligence. We’re going to parse the hype. Should we be preparing for our AI overlords?

But first, the latest on NASA’s Mars sample return mission. That’s the ambitious project that aims to use the Perseverance Rover to collect Martian rocks and sand, and even gulps of Martian air, and then, through a complicated hand-off between different spacecraft, return those Martian samples back to Earth.

In 2023, a review board said that the original plan to bring the samples back home would be much more expensive and take much longer than originally planned. So this week, NASA announced two options on how to cut costs and bring the samples back to Earth by the late 2030s. But the agency did not commit to a plan, leaving it to the next administration to out. So is the mission on the rocks?

Joining me now to get us up to speed is my guest, Dr. Jim Bell, Professor of Earth and Space Exploration at Arizona State University, based in Tempe, Arizona, and distinguished visiting scientist at NASA’s Jet Laboratory. Dr. Bell, welcome back to Science Friday.

JIM BELL: Thanks for having me on, Flora.

FLORA LICHTMAN: OK, Jim. So what do you make of this announcement of these two possible plans with no commitment to either? Is this a good sign for the future of the mission, a bad sign, neutral? What’s your take?

JIM BELL: Well, the good news is that NASA is supportive of doing this mission, continuing to try to find ways to bring these spectacular samples that the Perseverance Rover is collecting back to the Earth. This has been the highest priority that’s been identified by the National Academy of Sciences and the planetary science community for this next decade.

The frustrating part is, as you said, it’s been a couple of years now that we’ve been trying to figure out how to get this mission on the books.

FLORA LICHTMAN: Yeah. So why has it taken this long to even just get some possible plan B’s?

JIM BELL: Yeah, I think the reason is it will be the most complicated robotic mission that NASA or any space agency has ever attempted. It’s a hard thing to do. And there are pieces of what need to be done, the big lander to go back to Mars, a rocket to launch the samples off the surface, an orbiter to rendezvous with those samples in Mars orbit, bring the samples back. The pieces exist from past missions, but putting those pieces together, as you alluded to earlier, is incredibly complex.

FLORA LICHTMAN: Yes.

JIM BELL: And hard things take time. And hard things take a lot of money.

FLORA LICHTMAN: Yeah. I mean, to me, it reminds me of like a relay in the Olympics or something. You just have to pass this baton to all these different spacecraft, robot to spacecraft. Does that sound right to you?

JIM BELL: Yeah. Or that game mousetrap. I don’t know if you played that as a kid, where you get all these different parts, and this part has to integrate with that part. And hand over to that part. And the ball has to keep moving forward. In this case, the ball is a collection of at least 30 amazing samples very carefully selected by the Perseverance Rover team on Mars.

FLORA LICHTMAN: Yeah, I want to talk about that. So this mission has two parts. Part 1 is collect the samples. Part 2 is send them back to Earth. So your team is working on part 1, working with the Perseverance Rover to collect the samples. What are you looking for? What makes a good sample?

JIM BELL: Yeah, that’s a great question. And we’ve thought a lot about that and started thinking about that a decade ago, when this mission was sort of dreamed up and thinking about where to send it. You know, think about it. Where would you go on the Earth to collect samples, to learn about the early history of life on Earth and the environment of the planet as a whole?

And it’s a tough problem. And there are dozens and dozens of places that were proposed. And ultimately, we chose a place that– by Earth standards– we thought would be considered habitable a long time ago on Mars, an ancient delta, an ancient crater lake, a place where there was water ponding and flowing on the surface, where there was sedimentary rocks, preserving anything that was flowing down into that lake.

On Earth, deltas like the Mississippi River delta, those are amazing places to preserve evidence of biology and life. And maybe that’s true on Mars, we thought. And so we’ve been trying to sample sedimentary rocks, mudstones, sandstones, delta deposits, the soil itself, and the basic kinds of chemistry and mineralogy, and the rocks, the volcanic rocks– really try to get a snapshot of an ancient environment that may preserve evidence of past life or past habitability on Mars, and also will tell us lots, we believe, about Mars just as a planet itself.

FLORA LICHTMAN: So Perseverance has already collected the samples, is what I’m gathering.

JIM BELL: Many of them, not all of them, but we’ve got more than 20 now collected.

FLORA LICHTMAN: Do people fight for it? Or are they like, no, I want this delta. And someone’s like, no, I want this mudstone.

JIM BELL: Fight? Yes, in a collegial way. We’re all on the same team. So there’s lots of heated discussions about, do we sample here? Do we drill there? Do we drive left? Do we drive right?

FLORA LICHTMAN: Yeah.

JIM BELL: But in the end, we’re all working towards the same goal.

FLORA LICHTMAN: So where are they stored? Is there a little hidey hole somewhere on Mars? Is there a shoebox in the Rover? Where do you put them?

JIM BELL: There’s two places that they’re stored. The main place is inside the Rover. Inside the front of the belly of the Rover, there’s a tray and an entire collection of sample tubes, and a little tiny robotic arm– I think about it like a little tiny Tyrannosaurus Rex arm– inside the Rover that moves those sample tubes around. They can pick them up and deliver them to the drill and the coring system, and then collect them from the coring system and put them back into the tray and seal them hermetically.

So most of the samples are stored in that tray. But 10 of the samples have already been dropped onto the surface. And so as a contingency, as just in case, the Rover doesn’t survive long enough to transfer the samples to this Mars sample return lander– in case that doesn’t happen, there are 10 of them out in a very flat parking lot kind of place in the crater that we’re at, just spread out across the surface. And a future mission could go pick those 10 up if we can’t get the primary samples out of the Rover itself.

FLORA LICHTMAN: Sample takeout, they’re just waiting for them to be picked up.

JIM BELL: That’s a great way to think of it. Yes, Yes.

FLORA LICHTMAN: OK, so NASA had this press conference talking about how to possibly get these samples back. Can you just give me a high-level overview of the options?

JIM BELL: So, as you mentioned earlier, the plan of record, it just has proven untenable in terms of schedule, because the samples wouldn’t come back until sometime in the 2040s. And in terms of cost, because some estimates of cost had it over $10, $11 billion. So the plans put forward are combination of try to trim the size of some of the components, lower the costs, use more what NASA calls heritage components, pieces that have flown into space before, like the sky crane system that landed the Curiosity and Perseverance rovers on Mars.

NASA engineers and others were able to sharpen their pencils and reduce the size of this rocket that needs to take the samples off of Mars, and lowered the mass, and get it into the realm of being able to use the sky crane and other kinds of equipment. So that lowers cost.

And the other part of it is bringing in more involvement of commercial space companies like SpaceX, or Intuitive Machines, Firefly. So there’s a big commercial space industry out there that is eager to get involved in NASA science missions. And while I don’t know all the details, I know a lot of us are looking forward to seeing what parts of the commercial space world NASA can bring in to help solve this problem.

FLORA LICHTMAN: Best case scenario, when do you think we might see these samples back on Earth?

JIM BELL: Best case scenario, for me, is like the second half of the 2030s. Hopefully before 2040.

FLORA LICHTMAN: Are there people who are like, I will not retire until these samples come back?

JIM BELL: [LAUGHS] Yeah, sign me up. Yes.

FLORA LICHTMAN: Is that you? Are you that person, Jim?

JIM BELL: I’m among them. Yes, I absolutely want to see. I’d love to see the dust on Mars with my own eyes and studying it with telescopes and spacecraft for decades. But more importantly, there’s a lot of amazing lab equipment and skill here on Earth that has been working on lunar samples and meteorite samples and asteroid samples, ready to get samples from Mars and uncover those secrets. And so the sooner we get those samples into amazing laboratories around the world, the better.

FLORA LICHTMAN: So imagine these samples have just arrived in the lab. You’re unboxing them. What would that moment feel like for you?

JIM BELL: Oh, Christmas morning. [LAUGHS] I mean, one of the realities of being involved in space exploration is it takes a lot of time. It takes years, decades, sometimes, of your professional career to realize these kinds of missions and their success. In the case of bringing back samples from Mars, it’s been something that hundreds and hundreds of people have been working to try to make happen literally for decades.

FLORA LICHTMAN: Because this is the way that we would figure out whether there was life on Mars, right? This is the way.

JIM BELL: Yeah, I mean, unless something just gets up and walks in front of our cameras, you’re absolutely right. We don’t actually have any evidence of anything like that happening, and we don’t expect it because life on Mars appears to– if there was life on Mars, it probably existed very early in the history of the planet. And we know from our own planet that the early history of life on Earth was very simple, single-celled, multicellular colonies of organisms, soft bodied, no fossils.

And the traces of that early life on the Earth, on our own planet, are incredibly difficult to find and study. And our expectation is that’s going to be true on Mars. And so the best that we can do is go to a place that has the best odds of preserving that subtle evidence, and then get those samples into the same kind of laboratories, the cutting edge laboratories on the Earth that study that subtle evidence for early life on our own planet.

FLORA LICHTMAN: That’s just about all the time we have. I’d like to thank my guest, Dr. Jim Bell, Professor of Earth and Space Exploration at Arizona State University, based in Tempe, Arizona, and distinguished visiting scientist at NASA’s Jet Laboratory. Thank you, Jim.

JIM BELL: Thanks, Flora. It’s been a lot of fun.

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