# What Are Mars’ Moons Really Made Of? Japan’s MMX Mission Will Find Out

An episode of [Bedtime Astronomy](https://invisiblenetwork.ai/podcast/1736397134), 2 Sep 2026, 30 min.

Audio: https://dts.podtrac.com/redirect.mp3/api.spreaker.com/download/episode/74193121/phonosp.mp3

Japan’s MMX mission is preparing to land on Mars’ moon Phobos, collect samples, and study Deimos to uncover whether the moons are captured asteroids or remnants of a massive impact. The mission could reveal clues about the delivery of water and organic materials to early Earth while testing technologies for future Mars exploration. With China’s Tianwen-3 pursuing a similar sample-return goal, a new race to bring Martian material back to Earth is underway. Thank you for listening to Bedtime Astronomy — your guide to the cosmos. New episodes on space exploration, NASA missions & the latest astronomy breakthroughs. This episode includes AI-generated content.

## Transcript

[0:03] Speaker 1: Welcome to Bedtime Astronomy. Explore the wonders of the cosmos
[0:07] Speaker 1: with our soothing Bedtime Astronomie podcast. Each episode offers a
[0:12] Speaker 1: gentle journey through the stars, planets, and beyond, perfect for
[0:16] Speaker 1: unwinding after a long day. Let's travel through the mysteries
[0:20] Speaker 1: of the universe as you drift off into a peaceful
[0:22] Speaker 1: slumber under the night sky.
[0:26] Speaker 2: I want you to hold out your hand for a second.
[0:28] Speaker 3: Just hold it out, palm up, and imagine feeling the
[0:32] Speaker 3: weight of two little packets of sugar resting right there
[0:36] Speaker 3: in the center of your palm.
[0:38] Speaker 2: Right.
[0:38] Speaker 3: It's practically nothing, exactly, or maybe like a couple of
[0:42] Speaker 3: small coins. It weighs barely ten grams. Now, what if
[0:46] Speaker 3: I told you that those ten grams, that tiny, almost
[0:49] Speaker 3: imperceptible amount of weight, could hold the absolute origins of
[0:53] Speaker 3: the entire Solar system.
[0:55] Speaker 4: It sounds like science fiction, honestly, it.
[0:57] Speaker 3: Really does, and potentially the origins of life on Earth itself.
[1:00] Speaker 3: It sounds like magic, but we are talking about an actual, literal, physical,
[1:05] Speaker 3: cosmic heist. That is well, it's on the verge of
[1:08] Speaker 3: taking place.
[1:09] Speaker 4: The premise is just staggering. When you break down the logistics.
[1:12] Speaker 4: I mean, we are talking about a spacecraft traveling millions
[1:15] Speaker 4: of miles across the dark void of space, essentially breaking
[1:19] Speaker 4: and entering onto an alien moon, grabbing just a tiny
[1:22] Speaker 4: pinch of dirt and rock, and making a break forward
[1:24] Speaker 4: back to Earth.
[1:25] Speaker 3: Okay, let's unpack this because Japan is getting ready to
[1:27] Speaker 3: do exactly this. The Japan Aerospace Exploration Agency or JAXA,
[1:33] Speaker 3: has this imminent, highly ambitious space mission called the Martian
[1:37] Speaker 3: Moons Exploration Mission or MMX MMX, and it's set to
[1:41] Speaker 3: blast off from the Tanagashima Space Center in the coming months.
[1:44] Speaker 3: It's an unmanned mission and its target isn't just Mars,
[1:47] Speaker 3: it's the moons of Mars, you know, Phobos and Demos.
[1:51] Speaker 4: And to understand the sheer audacity of this, we have
[1:54] Speaker 4: to look at the isotopic and chemical signatures locked inside
[1:57] Speaker 4: those ten grams. Because to the name eye, ten grams
[2:01] Speaker 4: of extraterrestrial dirt is just a smudge of gray powder.
[2:04] Speaker 3: Oh.
[2:05] Speaker 4: But structurally, on an atomic level, those ten grams are
[2:08] Speaker 4: an entirely unread encyclopedia of planetary history. Wow. They hold
[2:12] Speaker 4: records of billions of years of cosmic events, completely unaltered
[2:15] Speaker 4: by the weather, tectonic plates, or you know, the atmospheric
[2:18] Speaker 4: degradation that constantly erases geological history here.
[2:21] Speaker 3: On Earth, which means we are going to explore how
[2:23] Speaker 3: a tiny scoop of dirt from a Martian moon could
[2:26] Speaker 3: unravel our cosmic history. We have to look at the
[2:29] Speaker 3: mind bending engineering required to pull off this extraterrestrial heights. Oh, absolutely,
[2:34] Speaker 3: because landing a spaceship in near zero gravity is a
[2:37] Speaker 3: complete physics nightmare. And maybe most surprisingly, we need to
[2:41] Speaker 3: get into the intense, high stakes geopolitical race happening right
[2:45] Speaker 3: now to bring these secrets back to Earth first, because
[2:49] Speaker 3: Japan is not the only ones sprinting toward the finish line.
[2:52] Speaker 4: No they aren't. The geopolitical landscape of space exploration is
[2:55] Speaker 4: shifting dramatically. The race for Martian material is becoming one
[2:59] Speaker 4: of the finding scientific competitions of our era, fundamentally altering
[3:04] Speaker 4: how nations collaborate and compete.
[3:05] Speaker 2: It's a massive shift.
[3:07] Speaker 4: But before we get into the international politics, we really
[3:09] Speaker 4: have to unpack the intricate mechanics of the MMX mission itself.
[3:13] Speaker 4: The orbital choreography required to pull this off is just
[3:16] Speaker 4: a masterpiece of physics.
[3:18] Speaker 3: The timeline of this mission profile is what immediately stands
[3:21] Speaker 3: out to me. The MMX spacecraft launches, it travels the
[3:24] Speaker 3: millions of miles to Mars, and.
[3:26] Speaker 2: Then it just hangs out right.
[3:28] Speaker 4: It waits.
[3:29] Speaker 3: It is slated to spend roughly three years orbiting Mars.
[3:33] Speaker 3: Three entire years. The primary objective is to eventually touch
[3:37] Speaker 3: down on Phobos, the larger of Mars's two moons, scoop
[3:41] Speaker 3: up that minimum of ten grams of surface material, and
[3:44] Speaker 3: launch a return capsule back to Earth. And there's a
[3:47] Speaker 3: secondary objective too, Yeah, to conduct close fly by observations
[3:51] Speaker 3: of the other moon demos without actually landing.
[3:54] Speaker 4: And if the entire sequence executes successfully, the sample capsule
[3:57] Speaker 4: detaches from the main spacecraft, upon which, turning to our
[4:00] Speaker 4: planetary neighborhood, re enters Earth's atmosphere at a blistering speed
[4:04] Speaker 4: and parachutes down into the remote Australian outback around the
[4:08] Speaker 4: year twenty thirty one.
[4:09] Speaker 3: And they aren't going alone either. The spacecraft is deploying
[4:13] Speaker 3: a rover onto the surface of Fogos named id Efix.
[4:17] Speaker 4: I love that name.
[4:18] Speaker 2: Yeah.
[4:18] Speaker 3: If you are a fan of classic French comic books,
[4:20] Speaker 3: you'll recognize that as the name of Asterix's little dog.
[4:24] Speaker 3: Idfix will handle the localized surface observations on Phobos, basically
[4:27] Speaker 3: sniffing around the surface like a robotic scout.
[4:29] Speaker 4: The Idfix rover represents a critical piece of international collaboration,
[4:34] Speaker 4: highlighting the French Space Agency's contribution to the mission.
[4:38] Speaker 2: Right because having that ground truth is huge.
[4:40] Speaker 4: Exactly, having a surface asset providing localized data while the
[4:44] Speaker 4: main spacecraft operates from orbit is invaluable for characterizing the
[4:49] Speaker 4: regolith that's the loose, dest and broken rock. They need
[4:52] Speaker 4: to understand that before the main sampling event even happens.
[4:55] Speaker 3: But from an efficiency standpoint, spending three years in orbit
[4:59] Speaker 3: before the sample seems totally counterintuitive. I mean, you spend
[5:03] Speaker 3: all this time, all this fuel, billions of dollars to
[5:06] Speaker 3: fly to Mars. Why not just fly there, match orbit, sland,
[5:10] Speaker 3: grab the dirt and fly back. So our question, why
[5:13] Speaker 3: commit to a massive three year delay in a Martian orbit?
[5:16] Speaker 3: It's like circling a grocery store for three years just
[5:19] Speaker 3: to buy a single grade.
[5:20] Speaker 4: That's a funny way to put it. But what's fascinating
[5:22] Speaker 4: here is that those three years in orbit are the
[5:24] Speaker 4: most crucial phase for ensuring the mission doesn't end in
[5:28] Speaker 4: immediate disaster. You have to consider the physical reality of Phobos.
[5:32] Speaker 4: We aren't dealing with a smooth spherical moon like Earth's Moon,
[5:36] Speaker 4: which has been mapped by decades of orbiters down to
[5:39] Speaker 4: the meter. Phobos is a highly irregular body. It is lumpy,
[5:44] Speaker 4: heavily cratered, and just deeply uneven.
[5:47] Speaker 3: It basically looks like a giant, heavily scarred potato floating
[5:50] Speaker 3: in space.
[5:51] Speaker 2: It's not round at.
[5:51] Speaker 4: All, exactly a space potato, and that irregular shape creates
[5:55] Speaker 4: chaotic gravitational fields. When you insert a spacecraft into orbit
[5:59] Speaker 4: around fund a massive spherical body like Earth, the gravity
[6:03] Speaker 4: is relatively uniform. Your orbital mechanics follow predictable, smooth curves.
[6:08] Speaker 2: Because the mass is evenly distributed right.
[6:11] Speaker 4: But when a body is shaped like a potato, its
[6:13] Speaker 4: center of mass doesn't align perfectly with its geometric center.
[6:16] Speaker 4: You have mass concentrations or mask ons that tug on
[6:20] Speaker 4: the spacecraft unevenly.
[6:21] Speaker 2: Oh wow.
[6:22] Speaker 4: If you just plunge toward the surface without mapping those
[6:25] Speaker 4: gravitational anomalies, the spacecraft's targeting software would be instantly overwhelmed
[6:30] Speaker 4: by the unpredictable pulling and pushing.
[6:32] Speaker 2: So the three years is actually a painstaking mapping process exactly.
[6:36] Speaker 4: The spacecraft has to spend a vast amount of time
[6:38] Speaker 4: analyzing the gravitational anomalies, mapping the surface hazards, identifying boulders,
[6:44] Speaker 4: and measuring the slopes of craters.
[6:45] Speaker 2: It's all prep work.
[6:47] Speaker 4: Choosing a safe landing site on an irregular body requires
[6:50] Speaker 4: immense precision. If you pick a spot with a slight
[6:52] Speaker 4: incline or a spot where the regulith is too soft,
[6:55] Speaker 4: the mission fails upon contact and the.
[6:57] Speaker 3: Orbital insertion itself isn't Mars is moving. Phobos is moving
[7:02] Speaker 3: around Mars incredibly fast. It completes an orbit in just
[7:05] Speaker 3: over seven hours, and the MMX spacecraft has to slip
[7:09] Speaker 3: into that system and pace alongside it.
[7:11] Speaker 4: Phobos orbit so fast that to an observer on the
[7:13] Speaker 4: surface of Mars, it actually rises in the west and
[7:16] Speaker 4: sets in the east twice a day.
[7:18] Speaker 2: That is so weird to think about.
[7:19] Speaker 4: It really is so matching that velocity. Syncing up with
[7:23] Speaker 4: this rapidly moving, irregularly shaped object, and then spending years
[7:26] Speaker 4: studying its composition thermal properties in radiation environment is an
[7:30] Speaker 4: engineering necessity.
[7:31] Speaker 2: You can't just wing it.
[7:32] Speaker 4: No, you have to know the exact thermal inertia of
[7:36] Speaker 4: the surface, how fast it heats up and cools down,
[7:39] Speaker 4: because that tells you how dense the soil is. You
[7:41] Speaker 4: need to know if you are landing on solid rock
[7:44] Speaker 4: or a pool of incredibly fine talcum like dust.
[7:48] Speaker 3: Okay, so that answers the how of the orbital delay,
[7:51] Speaker 3: But that brings up the why. What makes Phobos and
[7:53] Speaker 3: demos so incredibly valuable to science? Why are these two weird,
[7:58] Speaker 3: lumpy little moons the target such a massive undertaking because.
[8:01] Speaker 4: They represent a glaring missing puzzle piece in our understanding
[8:04] Speaker 4: of planetary formation. The MMX mission aims to solve a
[8:08] Speaker 4: long standing mystery regarding how these moons came to exist
[8:11] Speaker 4: in the first place.
[8:12] Speaker 2: And getting that answer is a big deal.
[8:14] Speaker 4: It fundamentally alters our understanding of the history of the
[8:16] Speaker 4: Inner Solar System.
[8:18] Speaker 3: There are two great hypotheses competing to explain the origin
[8:20] Speaker 3: stories for these moons, and the mechanics behind them are
[8:23] Speaker 3: completely opposite to one another. We are looking at the
[8:26] Speaker 3: giant impact hypothesis versus the capture hypothesis.
[8:29] Speaker 4: The giant impact hypothesis is a story of absolute cosmic violence.
[8:34] Speaker 4: This theory suggests that long ago, in the early Solar System,
[8:37] Speaker 4: a massive celestial body, perhaps a rogue planetoid or a
[8:41] Speaker 4: colossal asteroid, collided directly with Mars.
[8:44] Speaker 3: The scale of a collision like that is hard to
[8:47] Speaker 3: even conceptualize. We aren't talking about a meteor leaving a crater.
[8:50] Speaker 3: We are talking about an impact that literally melts.
[8:53] Speaker 4: The crust, an impact of unimaginable kinetic energy. The force
[8:57] Speaker 4: of that collision would have blasted billions of tons of
[9:00] Speaker 4: Martian crust and mandle right past the planet's escape velocity,
[9:04] Speaker 4: ejecting it out into space.
[9:05] Speaker 2: Just planetary shrapnel everywhere.
[9:07] Speaker 4: Yes, this would have created a massive swirling ring of
[9:10] Speaker 4: molten debris and shattered rock orbiting around Mars over millions
[9:15] Speaker 4: of years. The physics of planetary accretion takeover. That debris
[9:18] Speaker 4: ring eventually cooled, and through mutual gravitational attraction, the particles
[9:22] Speaker 4: clumped together, coalescing into the two moons we see today,
[9:25] Speaker 4: Phobos and Demos.
[9:27] Speaker 3: So, if the giant impact theory is true, Phobos is
[9:30] Speaker 3: basically an amalgamation of ancient Martian crust that got violently
[9:33] Speaker 3: blown into orbit.
[9:34] Speaker 2: It's a child of Mars.
[9:36] Speaker 4: Yes, and we have precedent for this. The leading theory
[9:39] Speaker 4: for the formation of Earth's own moon is a giant
[9:42] Speaker 4: impact between the early Earth and a Mars sized body
[9:45] Speaker 4: named thea right, But the competing theory for Mars moons,
[9:49] Speaker 4: the capture hypothesis, tells a completely different story. In this scenario,
[9:54] Speaker 4: Phobos and Demos were not born near Mars at all.
[9:57] Speaker 2: They're adopted exactly.
[9:59] Speaker 4: Instead, there ancient rogue asteroids that originally formed in the frigid,
[10:04] Speaker 4: dark outer reaches of the Solar System, far beyond the
[10:07] Speaker 4: rocky inner planets.
[10:08] Speaker 3: Way out past the Asteroid belt, maybe out by Jupiter
[10:11] Speaker 3: or even further into the Kuiper Belt.
[10:13] Speaker 4: Over millions of years, gravitational perturbations, perhaps interactions with the
[10:17] Speaker 4: massive gravity wells of Jupiter or Saturn, disturb their orbits,
[10:21] Speaker 4: sending them plunging inward toward the Sun. As they wandered
[10:24] Speaker 4: into the inner Solar System, they passed too close to
[10:26] Speaker 4: Mars and got caught through a complex gravitational interaction. They've
[10:30] Speaker 4: led off enough kinetic energy to be snared by MARTA's
[10:33] Speaker 4: gravitational pull, becoming permanently trapped in orbit.
[10:36] Speaker 3: Okay, wait I have a question about the physics of that.
[10:38] Speaker 3: Here's where it gets really interesting. But if an asteroid
[10:41] Speaker 3: is falling in from Jupiter, it's picking up an immense
[10:43] Speaker 3: amount of speed as it drops toward the Sun. How
[10:46] Speaker 3: does Mars just catch it?
[10:49] Speaker 4: That's the tricky part.
[10:50] Speaker 3: Wouldn't it just fly right past like a comet? Gravity
[10:53] Speaker 3: alone can't slow something down, It just bends the path right.
[10:57] Speaker 4: That is a phenomenal point, and it's the exact reason
[11:00] Speaker 4: and the capture hypothesis is so fiercely debated. You are
[11:03] Speaker 4: entirely correct about orbital mechanics. If a rogue asteroid enters
[11:07] Speaker 4: a planet's gravitational sphere of influence, it will accelerate on
[11:11] Speaker 4: the way in and then decelerate on the way out,
[11:13] Speaker 4: ultimately leaving with the same relative speed it arrived with.
[11:16] Speaker 2: It will just be moving in a different direction.
[11:18] Speaker 4: Precisely to actually achieve orbital capture, you have to bleed
[11:22] Speaker 4: off kinetic energy during the encounter.
[11:24] Speaker 2: So what puts the brakes on?
[11:26] Speaker 4: There are two main mechanisms astrophysicists look at. The first
[11:30] Speaker 4: is aerocapture. In the early Solar System, Mars had a
[11:33] Speaker 4: much thicker, denser atmosphere.
[11:35] Speaker 2: Oh, so it acts like a parachute kind of.
[11:38] Speaker 4: If an incoming asteroid grazed the upper atmosphere of early Mars,
[11:42] Speaker 4: the atmospheric drag could act as a break, bleeding off
[11:45] Speaker 4: just enough speed to keep the asteroid from escaping back
[11:48] Speaker 4: into deep space.
[11:49] Speaker 2: And the second mechanism, it's a.
[11:51] Speaker 4: Three body interaction. If the asteroid was actually a binary
[11:55] Speaker 4: pair two rocks orbiting each other as they flew past Mars,
[11:59] Speaker 4: the gravitational chaote dance could result in one rock being
[12:03] Speaker 4: flung out at a higher speed while the other rock
[12:06] Speaker 4: loses energy and gets captured.
[12:08] Speaker 2: That is wild.
[12:09] Speaker 3: The Moon is either a chunk of Mars or the
[12:11] Speaker 3: surviving half of a binary asteroid pair that got ripped
[12:14] Speaker 3: apart by gravity. But why should we care if they
[12:17] Speaker 3: are blasted off Mars or kidnapped from the outer Solar System.
[12:20] Speaker 4: It sounds like trivia, but it's not right.
[12:22] Speaker 3: Whether these two lumpy rocks were blasted off the surface
[12:25] Speaker 3: or kidnapped. It's a great story, but why is it
[12:27] Speaker 3: worth billions of dollars to figure out?
[12:29] Speaker 4: It matters because of what it proves about the mechanics
[12:31] Speaker 4: of the early Solar System. If the capture theory is true,
[12:35] Speaker 4: it changes everything. It turns these moons into pristine, untouched
[12:39] Speaker 4: timed capsules from the outer Solar System that have been
[12:41] Speaker 4: conveniently stored right next door to us in orbit.
[12:44] Speaker 2: Like a cosmic museum.
[12:45] Speaker 4: Exactly if they are captured asteroids. It proves the specific
[12:49] Speaker 4: pathways that rogue objects took from the frozen outer limits
[12:53] Speaker 4: into the warmer, rocky inner regions.
[12:55] Speaker 3: And this connects directly to how habitable environments arose on
[12:58] Speaker 3: the terrestrial planet Mercury, Venus, Earth, and Mars. Because the
[13:03] Speaker 3: early Earth, right after it formed, was a blistering molten rock.
[13:08] Speaker 2: It was utterly.
[13:08] Speaker 4: Barren, completely inhospitable.
[13:10] Speaker 3: The things we need to survive water, organic compounds, volatile elements.
[13:16] Speaker 3: They weren't necessarily baked into the Earth from day one
[13:18] Speaker 3: in the quantities we see today.
[13:20] Speaker 4: No, the inner Solar System was too hot inside what
[13:22] Speaker 4: astrophysicists call the frost line or the snow line. The
[13:25] Speaker 4: intense radiation and heat from the young Sun prevented water
[13:29] Speaker 4: and other volatile compounds from condensing into solid ice. They
[13:32] Speaker 4: just vaporize right They were made as vapor and were
[13:35] Speaker 4: largely blown outward by the solar wind. Therefore, the rocky
[13:38] Speaker 4: planets that formed close to the Sun formed relatively dry.
[13:41] Speaker 4: The crucial life giving elements had to be delivered from
[13:44] Speaker 4: the much colder outer Solar System past the frost line,
[13:47] Speaker 4: where water could exist as solid ice.
[13:49] Speaker 2: Deliveries of the fundamental ingredients for life.
[13:52] Speaker 4: We call these transport mechanisms. During a period known as
[13:56] Speaker 4: the Late Heavy Bombardment, the inner planets were pummeled by
[13:59] Speaker 4: a relentless rain of comets and asteroids originating from the
[14:03] Speaker 4: Outer Solar System. These impactors brought the water that fills
[14:07] Speaker 4: our oceans and the organic molecules that form the building
[14:10] Speaker 4: blocks of life.
[14:12] Speaker 3: Let's look the insight from Patrick Mitchell, the French astrophysicist
[14:15] Speaker 3: working on the idfix rover. He pointed out that if
[14:18] Speaker 3: phobos and demos are indeed remnants of these early delivery systems,
[14:22] Speaker 3: they hold the absolute clues to the transport of materials
[14:25] Speaker 3: that were vital for the emergence of life on rocky planets.
[14:29] Speaker 4: We are essentially tracing the ancient shipping routes of the
[14:31] Speaker 4: Solar System. By analyzing the isotopic ratios of the oxygen, carbon,
[14:36] Speaker 4: and water locked in those ten grams of dirt, we
[14:39] Speaker 4: can definitively say yes, this matches the chemical signature of
[14:43] Speaker 4: the outer Solar.
[14:43] Speaker 2: System, which is incredible.
[14:45] Speaker 4: We aren't just looking for life on Mars with this mission,
[14:47] Speaker 4: We are looking at Mars moons to understand the literal
[14:49] Speaker 4: chemical ingredients that allowed life to flourish right here on Earth.
[14:53] Speaker 3: So what does this all mean for you? If you
[14:56] Speaker 3: look at a glass of water on your desk, or
[14:58] Speaker 3: if you think about the carb that makes up the
[15:00] Speaker 3: cells in your own body, the origin story of that
[15:04] Speaker 3: water and that carbon might be locked inside the dirt
[15:07] Speaker 3: on Phobos.
[15:08] Speaker 4: It's deeply personal in a cosmic sense.
[15:11] Speaker 3: If the capture theory is validated by the material MMX
[15:14] Speaker 3: brings back, we will have physical proof of the type
[15:17] Speaker 3: of asteroids that acted as the delivery trucks for our oceans.
[15:20] Speaker 3: But to read that story, we actually have to get
[15:22] Speaker 3: the dirt, and that brings us to the immense physical
[15:25] Speaker 3: difficulty of actually pulling this off.
[15:27] Speaker 4: Because great scientific rewards always require overcoming massive engineering hurdles,
[15:32] Speaker 4: MMX is facing one of the most perilous physical challenges
[15:35] Speaker 4: in modern space exploration. The incredibly low gravity of Phobos.
[15:39] Speaker 3: Phobos is tiny. It's only about fourteen miles across. Its
[15:43] Speaker 3: mass is minuscule compared to Earth, which means its gravitational
[15:47] Speaker 3: pull is almost non existent.
[15:49] Speaker 4: It's barely there.
[15:50] Speaker 3: The gravity on Phobos is roughly one two thousandth of
[15:54] Speaker 3: Earth's gravity. If you were standing on Phobos and you jumped,
[15:57] Speaker 3: you wouldn't just pop back down. The escapeable is so low,
[16:01] Speaker 3: about twenty five miles per hour, that a good sprint
[16:04] Speaker 3: and a hard jump could literally launch you into orbit.
[16:06] Speaker 4: And that near zero gravity environment creates an entirely different
[16:10] Speaker 4: paradigm of physics for spacecraft design. When you're trying to
[16:13] Speaker 4: land to spacecraft there, you aren't so much landing as
[16:16] Speaker 4: you are trying to delicately dock with the moving object
[16:19] Speaker 4: without bouncing off.
[16:20] Speaker 3: Akinari Uahara, an engineer at Mitsubushi Electric who is working
[16:24] Speaker 3: on this mission, highlighted that the development of the spacecraft's
[16:27] Speaker 3: landing legs is particularly difficult. You can't just rely on
[16:31] Speaker 3: weight to keep the probe planted now.
[16:33] Speaker 4: Whara explicitly noted the critical need for legs that can
[16:37] Speaker 4: absorb and completely dissipate the kinetic energy of the impact.
[16:41] Speaker 4: In standard Earth gravity, if you drop an object, it
[16:44] Speaker 4: hits the ground, maybe bounces slightly and quickly settles because
[16:47] Speaker 4: gravity is constantly pulling it downward, overcoming the upward force
[16:51] Speaker 4: of the bounce right.
[16:52] Speaker 2: Gravity does the work for you.
[16:53] Speaker 4: But in microgravity the coefficient of restitution how much kinetic
[16:57] Speaker 4: energy remains after the impact, because comes your biggest enemy.
[17:01] Speaker 4: If the shock absorbers don't perfectly nullify that energy, the
[17:05] Speaker 4: spacecraft will literally bounce back up into space, tumbling out
[17:08] Speaker 4: of control.
[17:09] Speaker 3: It's like trying to land a heavy helicopter on a
[17:11] Speaker 3: trampoline in slow motion. If you come down even slightly
[17:15] Speaker 3: too fast or at a slight angle, the suspension springs
[17:18] Speaker 3: back and you flip over.
[17:19] Speaker 4: That's the great analogy.
[17:21] Speaker 3: And if the probe tips over, the mission is completely ruined.
[17:24] Speaker 3: You can't scoop the dirt if your scoop is pointing
[17:27] Speaker 3: at the stars. So how do they actually engineer legs
[17:30] Speaker 3: that don't bounce? Are they using hydraulics?
[17:33] Speaker 4: Traditional hydraulics can be risky in deep space due to
[17:36] Speaker 4: the extreme temperature fluctuations freezing the fluids. Often engineers rely
[17:41] Speaker 4: on crushable materials like aluminum honeycomb structures inside the leg struts.
[17:45] Speaker 2: Oh like crumple zones in a car.
[17:47] Speaker 4: Exactly when the spacecraft makes contact, the honeycomb permanently crushes
[17:51] Speaker 4: and deforms, absorbing the kinetic energy without acting like a
[17:54] Speaker 4: spring that pushes back. But you only get one shot
[17:57] Speaker 4: at that. Once the honeycomb is crushed, it's done.
[18:00] Speaker 3: And we have very recent stark cautionary tales about how
[18:03] Speaker 3: difficult this is. Like Japan's own recent lunar mission, the
[18:07] Speaker 3: smart Lander for Investigating Moon, known as SLIM.
[18:11] Speaker 4: Or the Moon Sniper. Yes. In twenty twenty four, SLIM
[18:15] Speaker 4: achieved an incredibly precise pinpoint touchdown on Earth's Moon. The
[18:19] Speaker 4: navigation software worked flawlessly, but during the final dissent, an
[18:23] Speaker 4: anomaly in one of the main engines caused a loss.
[18:25] Speaker 2: Of thrust, which threw everything off.
[18:27] Speaker 4: It induced a lateral velocity, meaning the spacecraft was moving
[18:30] Speaker 4: slightly sideways as it touched down, and that.
[18:32] Speaker 3: Lateral movement caused it to tip over. Upon landing, it
[18:36] Speaker 3: ended up resting on its nose.
[18:37] Speaker 4: Remarkably, SLIM was such a robust piece of engineering that
[18:41] Speaker 4: even resting upside down, it survived.
[18:43] Speaker 2: Yeah.
[18:43] Speaker 4: Once the sun angle changed and hit its solar panels,
[18:45] Speaker 4: it managed to wake up, transmit data and survived several
[18:48] Speaker 4: grueling two week lunar.
[18:49] Speaker 2: Nights, which is incredible.
[18:51] Speaker 4: That is a massive testament to JAXA's engineer resilience. But
[18:54] Speaker 4: you cannot afford a tip over when your primary objective
[18:57] Speaker 4: requires deploying a mechanical sampling arm into the soil beneath you.
[19:01] Speaker 3: But Japan also has an incredible pedigree of success when
[19:04] Speaker 3: it comes to the exact thing MMX is trying to
[19:06] Speaker 3: do bringing back pieces of the Solar System. The Hyabusa
[19:10] Speaker 3: two mission is the foundational proof of concept that makes
[19:14] Speaker 3: MMX possible.
[19:15] Speaker 4: Absolutely. In twenty twenty, the unmanned Hyabusa two spacecraft successfully
[19:20] Speaker 4: returned to Earth with samples that had collected from an
[19:23] Speaker 4: asteroid named Reyugu, located hundreds of millions of kilanders away.
[19:27] Speaker 3: It brought back exactly five point four grounds of rock
[19:30] Speaker 3: and dust. At the time, that was a massive scientific triumph.
[19:34] Speaker 3: Now with MMX, they are aiming to almost double that
[19:37] Speaker 3: payload to a minimum of ten grams. But how did
[19:40] Speaker 3: Hyabusa two actually grab the dirt without landing permanently.
[19:43] Speaker 4: It used a highly innovative mechanism. Instead of landing and
[19:46] Speaker 4: scooping with a shovel, Hyabus two descended kissed the surface
[19:50] Speaker 4: of the asteroid with a long sampler horn and at
[19:52] Speaker 4: the exact moment of contact, fired a small tantalum bullet
[19:56] Speaker 4: into the rock at high speed.
[19:57] Speaker 2: A bullet that's amazing.
[19:59] Speaker 4: Yeah. The impact to the bullet kicked up a cloud
[20:01] Speaker 4: of debris and dust which traveled up the horn and
[20:03] Speaker 4: was captured in the sample container. The spacecraft that immediately
[20:06] Speaker 4: fired its thrusters to back away.
[20:08] Speaker 3: It's a literal touch and go maneuver, and every single
[20:11] Speaker 3: mission feeds into the next. The precise targeting data and
[20:14] Speaker 3: sampling mechanisms from Hayabusa to combined with the shock absorbing
[20:18] Speaker 3: leg data and the tipover analysis from the slim Lunar lander,
[20:23] Speaker 3: all of that hard won data is being synthesized by
[20:25] Speaker 3: engineers to design the perfect bounced proof architecture for MMX.
[20:30] Speaker 4: The iterative nature of space exploration means that a failure
[20:34] Speaker 4: or a complication is often just as valuable as a
[20:37] Speaker 4: flawless success, provided you survive long enough to transmit the
[20:40] Speaker 4: telemetry data. They know exactly how much lateral velocity takes
[20:44] Speaker 4: to tip a lander now, and the NMAX flight software
[20:46] Speaker 4: will be written to aggressively correct for it.
[20:48] Speaker 3: But there's another massive component to this mission. They aren't
[20:51] Speaker 3: just going to Phobos to look into the past and
[20:53] Speaker 3: solve the origins of water on Earth. JXA is actively
[20:57] Speaker 3: using this mission to prepare for the future of human spaces.
[21:00] Speaker 4: The long term vision is extraordinary.
[21:02] Speaker 3: We are talking about stepping stones to Mars because JXA
[21:06] Speaker 3: has explicitly stated that they are exploring the possibility of
[21:09] Speaker 3: using Phobos as a natural space station.
[21:11] Speaker 2: I mean, how sci fi does that sound?
[21:13] Speaker 4: If we connect this to the bigger picture, this is
[21:15] Speaker 4: one of the most visionary aspects of the entire endeavor.
[21:20] Speaker 4: It represents the radical shift in how we approach deep
[21:22] Speaker 4: space architecture. Treating a Moon like an orbital pit stop
[21:27] Speaker 4: or a staging ground for human astronauts solves several critical
[21:30] Speaker 4: bottlenecks and crude Mars exploration.
[21:33] Speaker 3: To understand why a natural space station is brilliant, we
[21:35] Speaker 3: have to talk about the hardest part of going to
[21:37] Speaker 3: Mars coming back. Getting to Mars is relatively straightforward. Landing
[21:42] Speaker 3: on Mars is hard, but taking off on the surface
[21:45] Speaker 3: of Mars to come home is an absolute nightmare of physics.
[21:48] Speaker 4: It comes down to the tyranny of the rocket equation
[21:50] Speaker 4: and delta VV, the change in velocity required to perform
[21:54] Speaker 4: a maneuver. Mars has a significant gravitational wall. It has
[21:58] Speaker 4: about thirty eight percent of Earth's.
[21:59] Speaker 2: Gravity, which is a lot to fight against.
[22:01] Speaker 4: Taking off from the surface of Mars and achieving orbit
[22:04] Speaker 4: requires a massive rocket and tons of chemical propellant. To
[22:07] Speaker 4: get that propellant to the surface of Mars in the
[22:09] Speaker 4: first place, you need an even more massive rocket launching
[22:12] Speaker 4: from Earth. Every kilogram of payload you want to bring
[22:15] Speaker 4: back requires exponentially more fuel at the start of the journey.
[22:19] Speaker 3: It's not like the Apollo missions to our moon. Earth's
[22:21] Speaker 3: moon has one six of our gravity and no atmosphere.
[22:25] Speaker 3: A small ascent module could just pop back up to orbit.
[22:28] Speaker 3: Mars will pull you back down hard, and you have
[22:30] Speaker 3: to fight your way through an atmosphere to get to
[22:32] Speaker 3: space exactly.
[22:33] Speaker 4: But if you utilize Phobos, which is already perfectly situated
[22:37] Speaker 4: in equatorial Mars orbit yeah, and has almost zero gravity,
[22:40] Speaker 4: the math changes entirely. You can preposition your heavy return
[22:44] Speaker 4: fuel there over several unmanned cargo flights.
[22:47] Speaker 2: Oh, that makes so much sense.
[22:48] Speaker 4: You can have the main heavily shielded return vessel dock
[22:52] Speaker 4: to Phobos. Astronauts could travel from Earth to Phobos, park
[22:55] Speaker 4: the return ship, and then take a much smaller, lightweight
[22:58] Speaker 4: descent vehicle down to the Martian surface.
[23:01] Speaker 3: They do their surface work, ascend back to Phobos in
[23:03] Speaker 3: a small, efficient vehicle, and transfer to a fully fueled,
[23:07] Speaker 3: comfortable return vehicle that doesn't have to fight Martian gravity
[23:10] Speaker 3: to begin its journey home, because taking off from Phobos
[23:13] Speaker 3: requires almost zero fuel, essentially just gently push away and
[23:16] Speaker 3: fire your main engines.
[23:18] Speaker 4: Phobos also offers natural radiation shielding. Deep space is a
[23:22] Speaker 4: wash in deadly cosmic rays and solda radiation. If astronauts
[23:27] Speaker 4: can burrow into the regolith of Phobos or use it
[23:30] Speaker 4: to shield their habitat, it vastly increases the safety margins
[23:33] Speaker 4: for a multi year Mars mission.
[23:35] Speaker 2: A natural bunker.
[23:36] Speaker 4: Furthermore, astronauts station on Phobos could teleoperate rovers on the
[23:40] Speaker 4: Martian surface in real time.
[23:42] Speaker 3: Because the signal delay from Earth to Mars can be
[23:45] Speaker 3: up to twenty minutes each way. If you are driving
[23:47] Speaker 3: a rover from Earth and you see a cliff, by
[23:49] Speaker 3: the time you hit the brake's command reaches Mars, the
[23:52] Speaker 3: rover has been falling for twenty minutes. It's a huge
[23:55] Speaker 3: operational hurdle, but from Phobos, the light delay is fractions
[23:58] Speaker 3: of a second. You could I've rovaled with the joystick
[24:01] Speaker 3: in real time. It's not just the scientific probe, it's
[24:04] Speaker 3: laying the infrastructure for human.
[24:05] Speaker 4: Astronauts and by mastering the technology for a robotic round
[24:09] Speaker 4: trip to Phobos. Right now, JAXA is proving out the
[24:13] Speaker 4: exact celestial mechanics, the rendezvous software, and the orbital staging
[24:17] Speaker 4: infrastructure required for a human crew to do it decades
[24:20] Speaker 4: from now.
[24:20] Speaker 3: But the drive to secure these answers the origins of life.
[24:24] Speaker 3: The staging ground for human exploration has sparked a fierce,
[24:29] Speaker 3: high stakes international space race, because whoever successfully retrieves and
[24:33] Speaker 3: analyzes that Martian material first gains immense scientific prestige and
[24:39] Speaker 3: technological dominance.
[24:40] Speaker 4: This raises an important question about global dynamics. MMX represents
[24:44] Speaker 4: a unified international collaboration. JAXA is the primary operator, but
[24:49] Speaker 4: they are working closely with France's CNS, Germany's DLR, NASA
[24:54] Speaker 4: from the United States, and the European Space Agency.
[24:56] Speaker 2: A massive coalition.
[24:58] Speaker 4: They have scores of universities in tech companies backing them.
[25:01] Speaker 4: But they face determined competition from other global powers who
[25:04] Speaker 4: are running their own independent architectures.
[25:06] Speaker 3: Let's look at the competitors. We have to start with
[25:08] Speaker 3: the United States and NASA. NASA has the Perseverance Rover,
[25:11] Speaker 3: which has been roaming the Jesuo Crater on the surface
[25:13] Speaker 3: of Mars since twenty twenty one. And the incredible thing
[25:16] Speaker 3: is Perseverance has already done the hardest part of sample collection.
[25:19] Speaker 4: It's been working tirelessly.
[25:21] Speaker 3: It has been drilling into the Martian crust, collecting pristine
[25:24] Speaker 3: rock cores and sealing them in highly engineered titanium tubes.
[25:29] Speaker 3: It's literally dropping them on the surface of Mars, leaving
[25:32] Speaker 3: a trail of samples just waiting to be picked up.
[25:35] Speaker 4: The Mars Sample Return architecture was supposed to be the
[25:38] Speaker 4: crowning achievement of the next decade for NASA. The plan
[25:41] Speaker 4: was to send a lander to Mars, deploy a Fetch
[25:44] Speaker 4: rover to collect those tubes, load them into a small
[25:47] Speaker 4: rocket called the Mars Ascent Vehicle, launch them into Mars orbit,
[25:51] Speaker 4: and have a European orbiter catch them and bring them
[25:53] Speaker 4: back to Earth.
[25:54] Speaker 3: It's an incredibly complex chain of events, but recently the
[25:57] Speaker 3: mission hit a massive political and fine financial brick wall.
[26:01] Speaker 3: I mean, the US has the samples literally sitting in
[26:04] Speaker 3: tubes on Mars, but politics pulled the plug. Yes.
[26:07] Speaker 4: Following a budget vote by the US Congress in January,
[26:10] Speaker 4: the administration under President Donald Trump effectively canceled the Mars
[26:13] Speaker 4: Sample return mission in its current form.
[26:15] Speaker 2: Just completely gutted the funding.
[26:17] Speaker 4: The funding was cut due to ballooning cost estimates and
[26:20] Speaker 4: timeline delays, the complexity of that ascent vehicle. Building a
[26:24] Speaker 4: rocket that can survive the journey to Mars, survived the
[26:27] Speaker 4: harsh temperature fluctuations on the surface, and then successfully launched
[26:30] Speaker 4: itself into orbit without a launch pad or a ground
[26:33] Speaker 4: control team. It proved to be a monumental engineering and
[26:37] Speaker 4: budgetary challenge.
[26:38] Speaker 2: It's a huge blow to the scientific community.
[26:40] Speaker 4: The cancelation demonstrates the vulnerability of multi decades scientific endeavors
[26:45] Speaker 4: to short term political and economic cycles.
[26:48] Speaker 2: It's stunning.
[26:49] Speaker 3: The United States successfully landed a nuclear powered rover slawlessly
[26:53] Speaker 3: drilled and sealed the samples, and then the political will
[26:56] Speaker 3: to fund the retrieval vehicle just evaporated. The most valuable
[27:01] Speaker 3: scientific material in human history sitting in tubes on the
[27:04] Speaker 3: surface of another planet, and terrestrial politics shut it.
[27:06] Speaker 4: Down, leaving a huge gap.
[27:08] Speaker 2: It effectively benches the United States and the sample return race,
[27:11] Speaker 2: at least in the short term, and in geopolitics, nature
[27:14] Speaker 2: abhors a vacuum.
[27:15] Speaker 4: With the US program stalled, China has aggressively stepped into
[27:18] Speaker 4: the spotlight to fill that vacuum. China has officially announced
[27:22] Speaker 4: its tean Win three spacecraft, scheduling a launch around twenty
[27:26] Speaker 4: twenty eight. Their explicit goal is to return samples directly
[27:30] Speaker 4: from the surface of Mars to Earth around twenty thirty one,
[27:33] Speaker 4: which is.
[27:33] Speaker 3: The exact same timeframe that MMX's sample return capsule is
[27:36] Speaker 3: slated to parachute into the Australian outback. We are looking
[27:40] Speaker 3: at a literal neck and neck finish line in twenty
[27:42] Speaker 3: thirty one between Japan bringing back pieces of Mars moons
[27:46] Speaker 3: and China bringing back pieces of Mars itself.
[27:48] Speaker 4: And we cannot underestimate China's technological capability here. In twenty
[27:53] Speaker 4: twenty one, their tan Win one mission successfully landed the
[27:56] Speaker 4: Zorrong rover on the surface of Mars, which.
[27:58] Speaker 2: Is incredibly hard to do.
[28:00] Speaker 4: Landing on Mars is notoriously difficult the atmosphere is thick
[28:03] Speaker 4: enough to create superheated plasma and burn up a spacecraft,
[28:05] Speaker 4: but too thin to slow it down with parachutes alone.
[28:08] Speaker 4: You have to execute a flawless entry, descent, and landing sequence,
[28:12] Speaker 4: often relying on supersonic parachutes and powered retro rockets.
[28:15] Speaker 2: And China did it on their first try.
[28:17] Speaker 4: They executed this flawlessly on their very first independent attempt.
[28:20] Speaker 3: Their progression has been staggering. The race is incredibly real.
[28:25] Speaker 3: Space exploration is as much about terrestrial politics, demonstrating technological
[28:30] Speaker 3: dominance and national prestige as it is about astrophysics. A
[28:34] Speaker 3: collaborative international coalition led by Japan is racing against the
[28:39] Speaker 3: highly focused, rapidly advancing space program of China.
[28:42] Speaker 4: It is a remarkable conversion subplanetary science, bleeding edge engineering
[28:47] Speaker 4: and global ambition. MMX is a mission that tests the
[28:51] Speaker 4: absolute limits of autonomous flight, software, material science, and orbal mechanics.
[28:56] Speaker 3: We started with ten grams of dirt in the palm
[28:58] Speaker 3: of your hand. Those ten ms carry the weight of
[29:00] Speaker 3: testing the capture versus impact theories, proving the physical shipping
[29:04] Speaker 3: routes of water to the early Earth, establishing the groundwork
[29:07] Speaker 3: for human infrastructure on Phobos and serving as the grand
[29:10] Speaker 3: prize in a geopolitical space race.
[29:12] Speaker 4: It's a lot of pressure for a handful.
[29:14] Speaker 2: Of dust, it really is.
[29:15] Speaker 3: But I want to leave you with a final mind
[29:17] Speaker 3: bending thought to ponder long after you wrap up here.
[29:20] Speaker 3: Let's assume MMS is successful. They bring back those ten grams.
[29:24] Speaker 3: Scientists analyze the isotopic signatures and they prove the capture hypothesis.
[29:28] Speaker 2: They prove that the.
[29:30] Speaker 3: Ingredients for life, the water, the complex organics, were delivered
[29:34] Speaker 3: to a dead, molten Earth by rogue asteroids crashing into
[29:38] Speaker 3: the inner planets. If life is essentially seated by celestial
[29:41] Speaker 3: delivery trucks, think about the rest of the universe.
[29:44] Speaker 4: It completely alters the statistical probability of life on a
[29:48] Speaker 4: galactic scale exactly.
[29:49] Speaker 3: We know there are billions of other star systems out there.
[29:53] Speaker 3: We are discovering rocky exoplanets orbiting distant stars every single day.
[29:58] Speaker 3: If the building blocks of life are just cosmic shrapnel
[30:01] Speaker 3: wandering through the dark, cold void until they get caught
[30:04] Speaker 3: in the gravity wells of inner planet, it makes you
[30:06] Speaker 3: wonder how many billions of other Phobos like deliveries are
[30:10] Speaker 3: happening across the galaxy right this very second. If the
[30:13] Speaker 3: ingredients for life are just waiting in the cold dark
[30:16] Speaker 3: to be captured by any passing world, what does that
[30:18] Speaker 3: mean for the abundance of life waiting to be found
[30:20] Speaker 3: in the universe. It makes you look up at the
[30:22] Speaker 3: night sky and those ten grams of dirt in a
[30:24] Speaker 3: completely different way.

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