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Speaker 2: We've all seen the pictures from Mars, right, It's incredible rovers, curiosity, perseverance.
Speaker 2: They're just engineering marvels.
Speaker 3: Absolutely peak technology, nuclear powered, incredibly complex systems, some of
Speaker 3: the size of a small car.
Speaker 2: And the science they send back is I mean, it's priceless.
Speaker 2: But there's always that butt, isn't there. The cost is
Speaker 2: enormous billions of dollars.
Speaker 3: That's one side, yeah, billions permission.
Speaker 2: And the other thing is they're slow. They cover ground
Speaker 2: really slowly. We measure their progress in what kilometers per year?
Speaker 3: That's pretty much it. And that's the fundamental trade off
Speaker 3: you make with that kind of traditional exploration. You get
Speaker 3: incredible precision, amazing longevity at one specific spot, but you
Speaker 3: totally sacrifice scale. Our picture of Mars, you know, the geography,
Speaker 3: the climate, It's been shaped for decades by what these
Speaker 3: very expensive wheeled robots can see right where they happen to.
Speaker 2: Be, which leaves a pretty big gap, doesn't it. What
Speaker 2: if you want to understand something huge like planet wide
Speaker 2: climate patterns, or I don't know, track geological futures over
Speaker 2: hundreds thousands of kilometers.
Speaker 3: Exactly, a single rover, however advanced, just crawling along it
Speaker 3: can't give you that big picture, that systemic, distributed view.
Speaker 3: And that's precisely why this other idea, the one we're
Speaker 3: looking at today is well, it's so radical, the tumbleweed
Speaker 3: rover concepts.
Speaker 2: Tumbleweed, Okay, Yeah.
Speaker 3: The idea is basically to ditch all that complex propulsion
Speaker 3: that motors the heavy wheels, the nuclear core, and instead
Speaker 3: use the most abundant resource on Mars.
Speaker 2: Which is the wind. You're talking about these sort of spherical,
Speaker 2: lightweight things just getting blown across the surface like giant
Speaker 2: planetary dandelions.
Speaker 3: That's a pretty good analogy, actually. Yeah, And look, we've
Speaker 3: just gotten some really critical results back from wind tunnel tests,
Speaker 3: field tests. This isn't just some sci fi fantasy anymore.
Speaker 3: It's quickly moving towards being a real possibility for future missions.
Speaker 2: Wow.
Speaker 3: Okay, so the really big question here is, you know,
Speaker 3: how can a massive ball we're talking five meters across
Speaker 3: just push by guts of when become this transformative technology?
Speaker 3: How does that let us explore Mars on a continental scale?
Speaker 2: It sounds more like a giant, very sophisticated beach ball
Speaker 2: than a rover.
Speaker 3: Huh. Well, it might look simple, but the science behind
Speaker 3: making it work is anything. But it seems simple, but
Speaker 3: it's actually more pragmatic and scientifically robust then you might
Speaker 3: think at first glance.
Speaker 2: Okay, let's unpack this then, because yeah, it sounds like
Speaker 2: it relies on radical simplification, but simplicity has to be
Speaker 2: grounded in some pretty solid physics.
Speaker 3: Right, absolutely, Let's start with the machine itself.
Speaker 2: Okay, define this tumble weed rover physically. What are we
Speaker 2: talking about? Size construction?
Speaker 3: Physically? Yeah, they're designed as ultra light weight spheres and
Speaker 3: the scale is well, it's kind of astonishing. Fully deployed, the
Speaker 3: target size is five meters in diameters five.
Speaker 2: Meter Wait a minute, perseverance is about three meters long.
Speaker 2: That's huge, like giraffe height rolling on Mars.
Speaker 3: Pretty much. Think about that visual. The structure itself is
Speaker 3: basically an advanced, very durable shell, maybe like a tough
Speaker 3: balloon made from extremely light but really resilient materials. The
Speaker 3: whole design is about maximizing that surface area while keeping
Speaker 3: the mass incredibly low.
Speaker 2: But why so big? Why five meters wouldn't something smaller
Speaker 2: be I don't know, easier to handle, easier to launch.
Speaker 3: Ah, But the size is actually the secret sauce. It's
Speaker 3: directly linked to the challenge of moving anything in Mars's
Speaker 3: atmosphere because it's so thin exactly compared to Earth, Mars
Speaker 3: has almost no atmosphere, less than one percent of ours
Speaker 3: at the surface. So to actually catch enough wind to move.
Speaker 2: You need a big sale.
Speaker 3: You need a huge surface area for that thin wind
Speaker 3: to push against. Combined with the absolute minimum possible weight,
Speaker 3: A five meters sphere seems to hit that sweet spot
Speaker 3: that optimal ratio of sail area to mass. It gives
Speaker 3: you enough oomph, enough rolling torque from the Martian wind.
Speaker 3: It's all engineered around fluid dynamics in that specific environment.
Speaker 2: Okay, so the entire mobility system is just harnessing Martian wind,
Speaker 2: Like you said, like the tumblewheez we see rolling across
Speaker 2: deserts on Earth as a model, which means you're basically
Speaker 2: swapping out the need for well for power sources, no
Speaker 2: complex motors, no RTGs.
Speaker 3: Precisely, and that leads straight to the core goal, the
Speaker 3: really revolutionary part, large scale and low cost exploration. When
Speaker 3: you use the wind that's already there, you sidestep massive
Speaker 3: engineering headaches. Think about traditional rovers, they often rely on
Speaker 3: those RTGs, radioisotope, thermoelectric generators.
Speaker 2: Some nuclear batteries.
Speaker 3: Yeah, basically nuclear batteries, super high cost, very heavy, politically
Speaker 3: tricky to get approved for launch. By taking RTGs out
Speaker 3: of the equation, along with motors, complex gears, heavy wheels,
Speaker 3: the cost just plummets. The whole platform becomes almost disposable,
Speaker 3: relatively speaking, and that opens the door to mass production.
Speaker 2: And if you cut the cost and complexity that much,
Speaker 2: suddenly you can think about not just sending one precious
Speaker 2: billion dollar machine exactly.
Speaker 3: You can employ the swarm strategy. The goal isn't one rover,
Speaker 3: it's deploying entire swarms of these relatively inexpensive rovers all
Speaker 3: at once.
Speaker 2: Swarm. Okay, now that changes things. What's the scientific advantage
Speaker 2: of having a whole bunch of these rolling around.
Speaker 3: That's where this mission concept really truly shines. The scientific
Speaker 3: payoff of a distributed swarm. You shift from measuring things
Speaker 3: at just one point.
Speaker 2: Like Curiosity does now.
Speaker 3: To systemic distributed sensing. The strategy allows for an unprecedented
Speaker 3: simultaneous view. As the team puts it of atmospheric and
Speaker 3: surface processes from different locations on Mars. We could track
Speaker 3: dynamic things happening across the planet that are basically invisible
Speaker 3: to us right now.
Speaker 2: That distributed sensing, Yeah, I can see how that's a
Speaker 2: game changer, especially for climate science, maybe large scale geology too.
Speaker 2: What kind of questions could you actually answer with, say,
Speaker 2: dozens of these spread across the continent and things we
Speaker 2: just can't tackle.
Speaker 3: Now, Okay, think about planetary climate modeling. Yeah, we know
Speaker 3: Mars has these huge, sometimes planet encircling dust storms, right, Yah,
Speaker 3: the massive ones and powerful atmosphere pressure waves sort of
Speaker 3: like big weather fronts moving cross Earth. With one rover
Speaker 3: like perseverance, you can see a wave pass over you.
Speaker 3: You get a snapshot in time at one place, right,
Speaker 3: But imagine you have fifty tumbleweeds spread out over a
Speaker 3: thousand kilometers. Suddenly you can map the pressure gradients, the
Speaker 3: temperature changes within the wave. Simultaneously, you can track its speed,
Speaker 3: how it evolves in real time across a huge area. Wow,
Speaker 3: that's just impossible. With single point sampling or thing geologically
Speaker 3: could give you statistical data on soil composition or magnetic
Speaker 3: fields over a vast region. You move beyond just finding
Speaker 3: one interesting rock. You start understanding planetary scale trends.
Speaker 2: Okay, so the rolling phase is obviously crucial for spreading
Speaker 2: them out and gathering that kind of data, But you
Speaker 2: mentioned there's more to it. The mission isn't just about rolling, that's.
Speaker 3: Right, and this is where it gets, as you said,
Speaker 3: really interesting. The rolling is the deployment method, getting the
Speaker 3: instruments distributed across strategic target areas. But once they reach
Speaker 3: those spots, maybe preplan zones or areas of interest identified
Speaker 3: during the traverse, they stop rolling. The plan is for
Speaker 3: them to actually collapse into fixed positions. Collapse, Yeah, they
Speaker 3: transform into permanent measurement stations dotted strategically across the Martian surface.
Speaker 2: Hold on, how does a five meter lightweight ball just
Speaker 2: stop and anchor itself? Does the source material give any
Speaker 2: clues about that mechanism, how do you deflate it or
Speaker 2: stick it to.
Speaker 3: The ground that specific mechanism. The how is likely still
Speaker 3: part of the team's ongoing development, probably proprietary at this stage,
Speaker 3: but the core concept involves a controlled deflation or maybe
Speaker 3: retraction of that outer shell. Okay, The key is that
Speaker 3: the interior payload bay, the part with the actual science instruments,
Speaker 3: needs to be secured to the ground somehow. This transition
Speaker 3: from mobile to static is absolutely essential for the long
Speaker 3: term science value.
Speaker 2: So they become little weather stations.
Speaker 3: Or something exactly, or size mix stations, radiation monitors. They
Speaker 3: can provide sustained measurements from fixed points over potentially years,
Speaker 3: tracking atmospheric pressure changes, temperature cycles, maybe detecting marsquakes, monitoring
Speaker 3: radiation levels. Long term, they can form a kind of
Speaker 3: data backbone across the planet.
Speaker 2: Or even communication relays for other future missions.
Speaker 3: That's definitely a potential application. So yeah, the movement phase
Speaker 3: is the deployment strategy getting them spread out. But the
Speaker 3: static phases where you get that really long term scientific
Speaker 3: return on investment.
Speaker 2: Okay, the concept is well, it's brilliant, but the practical
Speaker 2: side still feels daunting. We established Mars's atmosphere is incredibly thin.
Speaker 2: Trying to roll a giant, super lightweight ball in that
Speaker 2: low pressure, even with strong winds. It feels like it
Speaker 2: needed some serious proof.
Speaker 3: Hard evidence, absolutely essential. You can't just assume Earth physics
Speaker 3: scales directly to Mars, especially with atmospheres. The staling factors
Speaker 3: are notoriously tricky. So yes, The source material details two
Speaker 3: main experimental phases that have now provided that crucial proof
Speaker 3: of concept, right the tests.
Speaker 2: Let's start with phase one. That was the wind tunnel
Speaker 2: physics right July twenty twenty five at RHUs University's Planetary
Speaker 2: Environment Facility. They basically had to build a little piece
Speaker 2: of Mars on.
Speaker 3: Earth pretty much. They used scaled down prototypes for this,
Speaker 3: specifically models with diameters of thirty, forty and fifty centimeters.
Speaker 3: They put these inside a special wind tunnel.
Speaker 2: Chamber, and the key was the atmosphere, the absolute key.
Speaker 3: The tests were run under a very low atmosphere and
Speaker 3: pressure seventeen.
Speaker 2: Millibars seventeen okay, remind us Earth's atmosphere at sea level is.
Speaker 3: About one thy thirteen millibars, so seventeen is less than
Speaker 3: two percent of earth pressure. It's practically a near vacuum environment.
Speaker 2: Why is simulating that low pressure so vital and I
Speaker 2: imagine technically quite hard to do.
Speaker 3: It's vital because the way air interacts with the surface,
Speaker 3: the whole fluid dynamics picture changes dramatically at such low pressures.
Speaker 3: Air becomes highly rarefied, how wind actually pushes the sphere,
Speaker 3: how the sphere interacts with the ground through that thin air.
Speaker 3: It's just fundamentally different physics in here. Okay, if the
Speaker 3: rover design can roll efficiently at seventeen millibars, it tells
Speaker 3: you the basic aerodynamic and structural design works for Mars.
Speaker 3: And yeah, maintaining that low pressure while also generating controlled
Speaker 3: wind inside a chamber is definitely a technical challenge.
Speaker 2: Did they just test it on a flat surface?
Speaker 3: No, that was another critical part. They ran tests over
Speaker 3: five different simulated Mars terrains, things like smooth planes, rough
Speaker 3: rocky areas, fine sand surfaces with pebbles, even simulated boulder fields.
Speaker 3: They want to make sure it wasn't just a con
Speaker 3: set that worked on a perfectly smooth lab.
Speaker 2: Floor, right, because Mars isn't smooth, and the goal is
Speaker 2: to find that magic number right, the minimum wind speed
Speaker 2: needed to actually get these things rolling consistently across different terrains.
Speaker 2: What did they find?
Speaker 3: The results were really positive and remarkably consistent across the
Speaker 3: different setups. They found that sustained wind speeds of nine
Speaker 3: to ten meters per second were enough to set the
Speaker 3: models into continuous motion.
Speaker 2: Nine to ten meters per second. Okay, is that fast
Speaker 2: like hurricane speeds.
Speaker 3: Not hurricane No. On Earth, ten meters is about twenty
Speaker 3: two miles per hour, a strong breeze, maybe a moderate gale.
Speaker 3: But remember on Mars the ear is so thin you
Speaker 3: need dead speed to get enough force.
Speaker 2: And that threshold nine ten meters it worked even on
Speaker 2: the rough terrain, the pebbles, the boulders.
Speaker 3: That's what they found. It held true across all those
Speaker 3: Mars like terrains they simulated, which is a huge finding.
Speaker 3: It proves the basic mechanism is robust. It can handle
Speaker 3: different geological settings you'd expect to find on Mars.
Speaker 2: Okay, so it rolls, but that's only part of the puzzle.
Speaker 2: If this thing is tumbling end over end, how does
Speaker 2: the science package inside stay working? Can it even collect
Speaker 2: accurate data while it's bouncing?
Speaker 3: Around, great question, And that was the other major validation
Speaker 3: for the wind tunnel tests. Yeah, they had sensors on
Speaker 3: board the prototypes, and yes, the successfully recorded data even
Speaker 3: during that vigorous tumbling motion. Okay, and maybe even more critically,
Speaker 3: the actual physical behavior of the rover, how it accelerated
Speaker 3: its rolling speed, how it reacted to wind gusts. That
Speaker 3: behavior closely matched the complex computer models, the fluid dynamics
Speaker 3: simulations the team had previously developed.
Speaker 2: Why is matching the models so important? Is it just
Speaker 2: about proving their math was right.
Speaker 3: It's much more profound than just checking the math. It
Speaker 3: validates their ability to reliably predict where these things will go. Ah, Okay,
Speaker 3: think about it. If you're a mission control trying to
Speaker 3: manage a whole swarm of these things being blown around
Speaker 3: by the wind, you can't just rely on luck. You
Speaker 3: need high fidelity predictive.
Speaker 2: Model, right, You need to know roughly where they'll end
Speaker 2: up exactly.
Speaker 3: The our host results basically prove that the physics engine
Speaker 3: they're using to calculate, Okay, if the wind blows this
Speaker 3: way tomorrow, where will tumbleweed number seven likely be? That
Speaker 3: engine is accurate. That's absolutely fundamental for planning emission, for
Speaker 3: coordinating the swarm, for actually achieving the science goals.
Speaker 2: Okay, prediction is key. Now another practical thought. Mars isn't flat.
Speaker 2: It has hills, slopes, crater rims. A strong wind might
Speaker 2: push you up a gentle slope maybe, but what happens
Speaker 2: if the train gets steep? Can a wind blown ball
Speaker 2: actually climb up hill?
Speaker 3: That was a specific thing they tested in our house,
Speaker 3: and the results were pretty impressive. The scaled models showed
Speaker 3: they could climb a slope of eleven point five degrees
Speaker 3: inside that low pressure.
Speaker 2: Chamber eleven and a half degrees.
Speaker 3: Now, because of the differences in gravity between Earth and
Speaker 3: Mars and that low atmospheric density they calculator, they climbing
Speaker 3: eleven point five degrees in the chamber is equivalent to
Speaker 3: climbing roughly a thirty degree slope on the actual surface
Speaker 3: of Mars.
Speaker 2: Thirty degrees. Seriously, that's incredibly steep for any vehicle, let
Speaker 2: alone one that doesn't have powered wheels or direct steering.
Speaker 3: It is. It really pushes the boundaries of what we
Speaker 3: thought possible for passive mobility, and it dramatically increases the
Speaker 3: amount of Martian terrain that would theoretically be accessible to
Speaker 3: these rovers, fewer places they could get permanently stuck.
Speaker 2: That's a big deal for mission planning.
Speaker 3: Huge And get this, the lead scientist, Mario Yuaso Carvolio
Speaker 3: dipinto Balsamasso. He noted that these results are probably conservative,
Speaker 3: how so, because the small prototypes they used in the
Speaker 3: wind tunnel they were actually deliberately made heavier relative to
Speaker 3: their size than the final full scale five meter rover
Speaker 3: is designed to be.
Speaker 2: Ah So they were testing a harder to move version.
Speaker 3: Exactly, if they had perfectly scaled down the weight to
Speaker 3: surface area ratio, the actual threshold wind speed needed to
Speaker 3: get the real thing rolling on Mars might be even
Speaker 3: lower than that nine ten meters per second they measure, So.
Speaker 2: The reel rover might be even more responsive to the
Speaker 2: wind than these tests showed.
Speaker 3: That's the suggestion, which is very encouraging.
Speaker 2: Okay, so Phase one in the wind tunnel nailed down
Speaker 2: the physics, the mobility threshold, the slope climbing, and validated
Speaker 2: their predictive models. What was phase two about? That moved
Speaker 2: things out of the lab right right?
Speaker 3: Phase two is about real world operational data gathering. This
Speaker 3: was the field campaign. Back in April twenty twenty five,
Speaker 3: they took it to an inactive quarry in Mastricht in
Speaker 3: the Netherlands.
Speaker 2: Corey why there.
Speaker 3: Good analog for rough, rocky, irregular terrain, more realistic than
Speaker 3: a controlled lab surface, and for this test they used
Speaker 3: a larger prototypes a two point seven meters diameter version
Speaker 3: called the Tumbleweed Science Test.
Speaker 2: Bit so bigger, closer to the real scale. And the
Speaker 2: focus here wasn't if it rolls, but could the electronics
Speaker 2: survive and work exactly?
Speaker 3: The primary goal was proving that the internal science package
Speaker 3: the electronics could not only survive the chaotic tumbling motion
Speaker 3: over natural ground, but also rather clean usable scientific data
Speaker 3: while tumbling.
Speaker 2: What kind of instruments did this testbed carry? Was it
Speaker 2: just dummy weight or actual sensors?
Speaker 3: Actual sensors. It had a modular payload bay designed to
Speaker 3: fit standard off the shelf components, which helps keep costs
Speaker 3: down too. For this test. It carried a camera, a
Speaker 3: magnetometer for measuring magnetic fields, a GPS obviously for tracking
Speaker 3: his path on Earth during the test, and critically, an
Speaker 3: inertial measurement unit or IMU.
Speaker 2: Okay an IMU on a normal rover that helps with navigation,
Speaker 2: knowing its orientation precisely. But what does an IMU do
Speaker 2: inside something that's constantly spinning and tumbling. Seems like it
Speaker 2: would just be chaos.
Speaker 3: Well, the IMU is maybe the most critical piece for
Speaker 3: getting good data in this unique situation. It measures the
Speaker 3: rover's acceleration and its angular velocity. Basically, attracks exactly how
Speaker 3: fast and in which direction the sphere is rotating at
Speaker 3: every single moment.
Speaker 2: Okay.
Speaker 3: With that raw motion data, the onboard computer can then
Speaker 3: mathematically comp and state for the spin. It can essentially
Speaker 3: despin the readings from the other instruments.
Speaker 2: Ah, so it lets the camera take a stable picture
Speaker 2: or the magnetometer get a consistent reading even while the
Speaker 2: whole thing is rolling.
Speaker 3: Precisely, it allows you to extract stable, scientifically meaningful data
Speaker 3: streams from the chaos of the tumbling motion. And the
Speaker 3: mostric tests confirmed it worked. The platform successfully gathered and
Speaker 3: processed environmental data in real time while tumbling over that
Speaker 3: rough natural quarry terrain.
Speaker 2: Okay, so we have proof they can roll if the
Speaker 2: wind hits nine ten meters per second, they can climb
Speaker 2: surprisingly steep slopes, and they can actually collect scientific data
Speaker 2: while they're rolling. That brings us back to the big
Speaker 2: question about the fuel source you mentioned earlier. Near surface
Speaker 2: winds on Mars. We don't actually know that much about them.
Speaker 3: That's been the historical challenge. Yes, our understanding is patchy.
Speaker 3: Near surface winds are officially described as not well understood.
Speaker 3: Why because most of our data comes from landers or rovers.
Speaker 2: Which tend to land in relatively safe calm air.
Speaker 3: Exactly. We pick landing sites for safety primarily not necessarily,
Speaker 3: because they're the windiest places on Mars. So our data
Speaker 3: has been sparse and localized.
Speaker 2: That sounds like a potential achilles heel for the whole concept,
Speaker 2: doesn't it relying entirely on a power source that we
Speaker 2: admit we don't fully understand.
Speaker 3: It definitely would be except for some more recent data
Speaker 3: that's come in from let's say, non traditional wind sensors.
Speaker 3: And this new data really seems to bolster the tumbleweed
Speaker 3: idea quite significantly.
Speaker 1: Oh like what well.
Speaker 3: NASA's Insight Lander, for instance, its main job with seismology
Speaker 3: listening for marsquakes, but its seismometer.
Speaker 2: Was so sensitive it kicked up vibrations from the wind exactly.
Speaker 3: It recorded ground vibrations generated by the wind blowing across
Speaker 3: the lander in the surface, and it did this for
Speaker 3: over two Martian years, giving us a much longer baseline
Speaker 3: of wind activity at one location.
Speaker 2: Interesting any other sources, Yes.
Speaker 3: And perhaps even more directly relevant measurements taken during the
Speaker 3: flights of the Ingenuity Hell helicopter ah the little drone. Yeah.
Speaker 3: As it flew, it sensors gathered data on air density, temperature,
Speaker 3: and wind speeds much closer to the surface than orbiting
Speaker 3: satellites can measure. And what both Insight and Ingenuity showed
Speaker 3: was that higher wind speeds the kind cumble wheat needs
Speaker 3: seem to occur to hear the surface surprisingly frequently, more
Speaker 3: often than the older, lower average speeds typically reported.
Speaker 2: Okay, so we're getting better evidence that strong winds near
Speaker 2: the ground aren't just rare flukes. They might be a
Speaker 2: regular part of the Martian weather cycle. How does this
Speaker 2: new data line up with that ten meter per second
Speaker 2: threshold they need?
Speaker 3: The analysis, particularly of the Insight data by Mario's team,
Speaker 3: is really encouraging. They suggest that, especially in Mars's northern
Speaker 3: hemisphere during its summer season, the daytime wind speeds show
Speaker 3: a wide distribution, but it skewed towards those higher speeds.
Speaker 3: Needed Around ten meters per second isn't uncommon during the day.
Speaker 2: So it's like a reliable daily power source during summer days.
Speaker 3: That seems to be the pattern. And interestingly, even the nights,
Speaker 3: which are generally calmer, aren't always dead calm. They found
Speaker 3: that sometimes even at night, speeds can spike above ten
Speaker 3: meters per second, maybe due to atmospheric shifts or cold
Speaker 3: air drainage, winds flowing down slopes or canyon walls.
Speaker 2: Okay, so the fuel seems to be there, and maybe
Speaker 2: more reliably than we used to think. That's great news
Speaker 2: for planning emission. Now let's get to the numbers that
Speaker 2: really show why this is such a different approach the range.
Speaker 2: If you take that r who's wind tunnel data feed
Speaker 2: it into their validated prediction models, what kind of distances
Speaker 2: could these things actually cover on Mars.
Speaker 3: This is where the sheer advantage of just letting the
Speaker 3: wind do the work becomes incredibly clear. Their models predict
Speaker 3: that an average tumbleweed rover, just following the typical daily
Speaker 3: shifts and day night cycles of the Martian wind, it
Speaker 3: could travel about four hundred and twenty two kilometers over
Speaker 3: one hundred Martian souls.
Speaker 2: Four hundred and twenty two kilometers in one hundred souls, okay,
Speaker 2: sol is a Martian day just a bit longer than ours.
Speaker 3: Right, about twenty four hours in thirty nine minutes. So
Speaker 3: one hundred souls is roughly three earth months.
Speaker 2: Okay, let's put four hundred and twenty two kilometers in
Speaker 2: three months into perspective. How does that compare to say,
Speaker 2: Curiosity or perseverance.
Speaker 3: It absolutely dwarfs them. I mean, think about Curiosity. The
Speaker 3: gold Standard landed in twenty twelve. It took over a decade,
Speaker 3: ten years to drive a total distance of just over
Speaker 3: thirty kilometer.
Speaker 2: Thirty kilometers in ten years. Wow.
Speaker 3: Perseverance is on a similar track, measured in tens of
Speaker 3: kilometers total traverse. So far, this tumbleweed concept is projected
Speaker 3: to cover more than ten times the distance Curiosity managed
Speaker 3: in its entire mission in just the first three months.
Speaker 2: That's a completely different scale of exploration.
Speaker 3: It's moving from a slow, methodical crawl in one small
Speaker 3: area to potentially widespread, almost regional or continental coverage. That's
Speaker 3: the technological leap here.
Speaker 2: If you break down that four hundred and twenty two
Speaker 2: kilometers in one hundred souls, what's the average speed? Must
Speaker 2: still be pretty slow overall.
Speaker 3: The average overall speed works out to abouto point three
Speaker 3: to six kilometers per hour. Yeah, it sounds slow if
Speaker 3: you think about a car, but the key thing to
Speaker 3: remember is that speed is sustained whenever the wind blows adequately.
Speaker 3: It requires no fuel from the rover itself. It only
Speaker 3: stops when the wind drops below the threshold. It's persistent.
Speaker 2: Okay, So four hundred and twenty two kilometers is the
Speaker 2: average predition based on typical wind cycles. What about the
Speaker 2: best case scenario if you get lucky with strong, consistent
Speaker 2: winds blowing in the same general direction for a long time.
Speaker 2: What's the maximum potential range?
Speaker 3: According to their modeling under those ideal conditions favorable terrain,
Speaker 3: sustained strong winds, the maximum potential range is just staggering.
Speaker 3: A single tumbleweed rover could potentially traverse as much as
Speaker 3: twenty eight hundred kilometers.
Speaker 2: Twenty eight hundred kilometers, that's like driving from Chicago to Denver,
Speaker 2: or maybe halfway across the US.
Speaker 3: It's enormous. We're talking about the potential to map geological
Speaker 3: changes atmospheric phenomena across entire, vast regions of Mars that
Speaker 3: are currently completely inaccessible to us, all powered by nothing
Speaker 3: more than the thin Martian air. It really opens the
Speaker 3: door to true continent scale exploration.
Speaker 2: That twenty eight hundred kilometer figure, Wow, that really sells
Speaker 2: the vision. So who's behind this, who's the engine driving this? Well?
Speaker 2: Pretty bowl high risk but potentially a very high reward idea.
Speaker 3: The group is called Team Tumbleweed, and they're specifically described
Speaker 3: as an interdisciplinary group of young, entrepreneurial scientists. Their structure
Speaker 3: kind of reflects the whole low cost, high impact vibe
Speaker 3: of the project itself.
Speaker 2: Young and entrepreneurial often means agile, quick to adapt, and
Speaker 2: you mentioned they're international very much.
Speaker 3: So, which definitely helps when you're tackling a complex, multifaceted
Speaker 3: problem like this. While the main hubs seem to be
Speaker 3: in Vienna, Austria, and Delft in the Netherlands, the team
Speaker 3: actually brings together people from over twenty different countries.
Speaker 2: That's impressive. That global collaboration must be key for pulling
Speaker 2: together expertise in what atmospheric physics, material science, robotics, software, all.
Speaker 3: Of the above. You need all those disciplines working together
Speaker 3: simultaneously to make concept fly literally.
Speaker 2: Okay, so they've proven the basic physics works, they prove
Speaker 2: mobility and simulated Mars conditions. They prove they can collect
Speaker 2: data while tumbling. What are the next big steps? What
Speaker 2: do they need to do to get this platform from
Speaker 2: say a working prototype, to something genuinely flight ready.
Speaker 3: The main goal now is moving up the ladder of
Speaker 3: technology readiness levels or.
Speaker 2: Trls TRLS, right, that's the standard scale NASA and eesus
Speaker 2: to gauge how mature a space technology is. Isn't it
Speaker 2: goes from one to nine exactly?
Speaker 3: TRL one is just basic principles observed. Tier nine is
Speaker 3: flight proven on a successful mission. These recent tests, the
Speaker 3: wind tunnel and the Qrey field test have likely pushed
Speaker 3: Tumbleweed into the mid level TRLS, maybe TROL four or five.
Speaker 3: Validation in a lab or relevant environment.
Speaker 2: Okay.
Speaker 3: To get to flight readiness, say TRL seven, eight, or nine,
Speaker 3: they need to push forward on primarily two tracks.
Speaker 2: Now, Track one, I'm guessing is making those prediction models
Speaker 2: even better. Since you can't steer it, you absolutely have
Speaker 2: to know where it's going precisely.
Speaker 3: They need to keep refining those rover dynamics models. The
Speaker 3: real challenge is modeling the chaotic nature of Martian wind accurately.
Speaker 3: You've got turbulence, unpredictable gusts, maybe small dust devils that
Speaker 3: could knock it off course. Terrain features like canyons or
Speaker 3: large dune fields. It could block it or channel the
Speaker 3: wind in unexpected ways. Mission control needs models sophisticated enough
Speaker 3: that they can feed in the latest wind data, maybe
Speaker 3: from orbiters or other assets, and get reliable trajectory predictions hours,
Speaker 3: maybe even souls in advance. That's essential for coordinating the
Speaker 3: swarm and making sure they actually hit their scientific targets.
Speaker 2: What happens if one does get stuck, you know, rolls
Speaker 2: into a deep crack or gets wedged in a really
Speaker 2: dense field of boulders, there's no way to drive it out.
Speaker 2: How do they handle that inevitability?
Speaker 3: That's the inherent risk, and the operational philosophy has to
Speaker 3: accept it. There's no rescue capability like with a wheeled rover,
Speaker 3: so the mission relies on two things. First, that's surprising
Speaker 3: thirty degree slope climbing ability. We talked about that significantly
Speaker 3: reduces the chances of getting permanently stuck in many types
Speaker 3: of unfavorable.
Speaker 2: Terrain, okay, makes it more robust.
Speaker 3: Second, and maybe more importantly, the swarm strategy itself provides
Speaker 3: redundancy because each rover is relatively low cost. If one
Speaker 3: or two out of a swarm of say twenty, get incapacitated,
Speaker 3: it's not mission failure.
Speaker 2: It's an acceptable loss exactly.
Speaker 3: The overall mission continues with the remaining units. The low
Speaker 3: cost allows for a higher tolerance for individual unit failure
Speaker 3: compared to a single billion dollar asset.
Speaker 2: Okay. So refining prediction models is track one. What's track
Speaker 2: two for reaching higher trls? Integrating better instruments?
Speaker 3: Yes, moving beyond the foundational sensors like the camera and
Speaker 3: IMU that they used in the test bed. The next
Speaker 3: phase is about integrating more specialized science focused instruments into
Speaker 3: that payload bay. Instruments that really leverage the fact that
Speaker 3: you'll have many of these spread out.
Speaker 2: Like what specifically are they looking at.
Speaker 3: They're focusing on things like advanced radiation set to map
Speaker 3: radiation levels across different latitudes and terrains, specialized soil probes.
Speaker 3: Maybe something that can be quickly deployed or inserted into
Speaker 3: the ground when the rover naturally pauses for.
Speaker 2: A bit ah interesting like a little quick sample.
Speaker 3: Maybe, And also highly sensitive dust sensors. Given that the
Speaker 3: whole vehicle relies on atmospheric dynamics in Mars is famously dusty,
Speaker 3: understanding dust transport and properties across wide areas is crucial.
Speaker 3: These instruments make the platform much more scientifically potent.
Speaker 2: More sophisticated instruments, better models. That brings us to the
Speaker 2: next big test, doesn't it, the final really critical field
Speaker 2: test before they can claim high TRL status. They're going
Speaker 2: somewhere very specific, very Mars like.
Speaker 3: That's right. The next major field campaign is scheduled for November,
Speaker 3: and it's taking place in the Atacama Desert in Chile.
Speaker 2: The Atacamma, Yeah, that's famous for being one of the
Speaker 2: best Mars analog environments on Earth, Isn't it? Super dry,
Speaker 2: high altitude, intense UV.
Speaker 3: Exactly. It's about as close as you can get to
Speaker 3: Martian surface conditions without lee the planet ideal for pushing
Speaker 3: the system to its limits?
Speaker 2: And what's the main goal in the Atacamma. It's not
Speaker 2: just about proving one rover can roll again.
Speaker 3: Right, No, this is a system's level test. The plan
Speaker 3: is to deploy at least two of the Tumbleweed Science
Speaker 3: Test bed rovers simultaneously and significantly, they'll be carrying instruments
Speaker 3: provided by researchers from external partner organizations.
Speaker 2: Oh interesting, So other science teams are starting to buy in,
Speaker 2: wanting to get their instruments on this platform, it seems so.
Speaker 3: That's a really good sign for the project's credibility within
Speaker 3: the wider planetary science community. But the absolute key objective
Speaker 3: in the ATA comma, the thing they really need to
Speaker 3: nail down the swarm. Yes, operationalizing the core concept the
Speaker 3: swarm itself.
Speaker 2: Testing how multiple windblown balls coordinate with each other? How
Speaker 2: does that even work?
Speaker 3: That's what they need to figure out and demonstrate. The
Speaker 3: priory goal is testing and validating the swarm coordination strategies
Speaker 3: in that realistic, harsh Mars like environment. This involves some
Speaker 3: pretty complex software and algorithms. How do two or more
Speaker 3: rovers constantly moving semi randomly based on the wind maintain
Speaker 3: communication links?
Speaker 2: Yeah? How do they talk to each other?
Speaker 3: How do they coordinate their science? For example, can mission
Speaker 3: control instruct one rover that happens to be an interesting
Speaker 3: spot to try and stop or slow down to take
Speaker 3: a soil measurement while another nearby rover keeps rolling to
Speaker 3: track an incoming weatherfront. Can they re elect data between
Speaker 3: themselves to get back to an orbiter.
Speaker 2: So it's moving way beyond just a single tech demo.
Speaker 2: It's about proving they can operate as an intelligent distributed.
Speaker 3: Network, precisely autonomous coordination. That's the final piece needed to
Speaker 3: show this is a viable, functional scientific exploration strategy ready
Speaker 3: for space.
Speaker 2: So they're really ticking the boxes mobility, proven data integrity,
Speaker 2: while tumbling, proven wind availability, looking more promising, slow climbing
Speaker 2: capability demonstrated, and now the final hurdle. Autonomous swarm coordination
Speaker 2: in a Mars like place.
Speaker 3: Really is the comprehensive arc of the validation process they've undertaken.
Speaker 3: It's fascinating, isn't it. The core idea is so simple,
Speaker 3: let the wind push it. But making it actually work
Speaker 3: reliably as a coordinated scientific tool requires this incredibly complex,
Speaker 3: highly specialized software and system design to manage the inherent
Speaker 3: chaos of the environment.
Speaker 2: It really is a remarkable achievement just to get to
Speaker 2: the stage all this experimental validation. It feels like it
Speaker 2: successfully dragged the tumbleweed concept out of the realm of
Speaker 2: cool idea and into something measured, practical, application focused. They've
Speaker 2: shown the mobility works. They can survive steep slopes, they
Speaker 2: can get real time data, all using Martian wind.
Speaker 3: Yeah. I think this project really signifies a potential shift,
Speaker 3: maybe a fundamental one, in how we think about exploring planets.
Speaker 3: We could be moving away, or at least augmenting the
Speaker 3: traditional model centralized very high cost, low moving platforms towards
Speaker 3: methods that are inherently cheaper, much more extensive in coverage,
Speaker 3: and actually use the planetary environment itself for mobility.
Speaker 2: Right.
Speaker 3: It just completely redefines what parts of Mars we consider accessible.
Speaker 3: The Tumbleweed is kind of a testament to the idea
Speaker 3: that sometimes the biggest breakthroughs come from embracing well radical
Speaker 3: simplification in the core engineering, even if the supporting systems
Speaker 3: get complex.
Speaker 2: So what does this huge leap in potential coverage actually
Speaker 2: mean for the science we can do on Mars? If
Speaker 2: you really could have dozens of these low cost sensors
Speaker 2: rolling potentially thousands of kilometers like that twenty eight hundred
Speaker 2: kilometer max range. What revolutionary questions could we finally answer
Speaker 2: things that are impossible now, Questions that only as swarm
Speaker 2: traversing continents simultaneously could tackle. Think about tracking atmospheric waves
Speaker 2: or mapping huge geological boundaries over time. What discoveries might
Speaker 2: be out there just waiting for a rover that doesn't
Speaker 2: need to stop for fuel, doesn't need complex repairs, It
Speaker 2: just needs the wind to blow.
Speaker 3: That's the million dollar question, isn't it, or maybe the
Speaker 3: multimillion dollar question. Even if the rovers themselves are cheaper,
Speaker 3: it genuinely changes the scale of what we even think
Speaker 3: of as planetary exploration.