# A New Mission Opportunity Could Bring JUICE Close to Jupiter’s Mysterious Moon

An episode of [Bedtime Astronomy](https://invisiblenetwork.ai/podcast/1736397134), 9 Sep 2026, 39 min.

Audio: https://dts.podtrac.com/redirect.mp3/api.spreaker.com/download/episode/74779501/jupitermoonp.mp3

Scientists are taking a closer look at Kallichore, one of Jupiter’s smallest and least understood moons, ahead of potential exploration by ESA’s JUICE spacecraft. By refining its orbit and physical characteristics, researchers reduced positioning errors by 80%, helping enable a possible future flyby. This tiny, dark world could offer rare clues about the early solar system. 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 Astronomy 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.
[0:27] Speaker 2: Imagine, just for a second, that you are packing your
[0:30] Speaker 2: bags for the ultimate road trip. But you aren't just
[0:33] Speaker 2: crossing a country or, you know, even a continent. You
[0:36] Speaker 2: are crossing the entire solar system.
[0:38] Speaker 3: Right. A massive journey.
[0:39] Speaker 2: Exactly. And your destination is Jupiter. Now, naturally, if you're
[0:45] Speaker 2: making that unimaginably long trek across the cold, empty void
[0:49] Speaker 2: of deep space, taking years of your life to get there,
[0:52] Speaker 2: you are going to want to visit the famous destination.
[0:54] Speaker 3: Oh, absolutely. The tourist spots.
[0:56] Speaker 2: Yeah. You want to see the massive glittering moons with
[0:59] Speaker 2: their towering sulfur volcanoes. Or the ones with hidden, world-spanning
[1:03] Speaker 2: oceans buried beneath miles of cracked ice. You want the
[1:06] Speaker 2: postcard views, you know. You want to see the things
[1:08] Speaker 2: that dazzle the eye.
[1:09] Speaker 3: The things that look spectacular in the photos.
[1:11] Speaker 1: Right.
[1:12] Speaker 2: But what if I told you the most important stop
[1:14] Speaker 2: on your entire itinerary wasn't a glittering, icy world at all?
[1:19] Speaker 2: What if the absolute most crucial destination was a tiny,
[1:22] Speaker 2: pitch-black pebble hurtling chaotically through the darkness, completely invisible to
[1:27] Speaker 2: the naked eye?
[1:28] Speaker 3: It really is wild to think about. It completely flips
[1:32] Speaker 3: our human intuition about what makes a destination valuable. We're,
[1:36] Speaker 3: you know, we're instinctively drawn to the spectacular, the bright,
[1:39] Speaker 3: and the active.
[1:39] Speaker 2: We like shiny things.
[1:40] Speaker 1: We do.
[1:41] Speaker 3: But in planetary science, those flashy characteristics are often distractions.
[1:46] Speaker 3: The quiet, the dark, and the entirely overlooked corners of
[1:50] Speaker 3: our cosmic neighborhood, they often hold the most profound secrets
[1:54] Speaker 3: about our own origins.
[1:55] Speaker 2: And that brings us to today's mission. We are exploring
[1:57] Speaker 2: the European Space Agency's GIE spacecraft. That stands for Jupiter
[2:02] Speaker 2: Icy Moons Explorer, by the way. And we're looking at
[2:05] Speaker 2: its unbelievably ambitious plan for October 2031.
[2:08] Speaker 3: A really, really critical milestone.
[2:11] Speaker 2: It is. This billion-dollar spacecraft is attempting to intercept a tiny,
[2:15] Speaker 2: irregular moon named Calicor. So our mission in this conversation
[2:19] Speaker 2: today is to uncover exactly why thousands of scientists and engineers...
[2:22] Speaker 2: are so utterly fixated on a 3.8 kilometer speck of rock.
[2:26] Speaker 3: It's a tiny target. So tiny. We are going to
[2:29] Speaker 3: figure out how human beings manage to even track something
[2:33] Speaker 3: so incredibly dark and distant and most importantly, what this
[2:37] Speaker 3: stealthy ancient moon can reveal about the very darn of
[2:42] Speaker 3: our solar system.
[2:43] Speaker 2: The scale of this endeavor represents a phenomenal challenge. I mean,
[2:48] Speaker 2: both in terms of theoretical astrophysics and well, just Practical engineering.
[2:53] Speaker 3: Yeah, building the thing.
[2:55] Speaker 2: Right, because the target is an object that barely reflects
[2:58] Speaker 2: any light. It's moving in a highly unpredictable path, and
[3:01] Speaker 2: it's hundreds of millions of miles away from Earth. It
[3:04] Speaker 2: tests the absolute limits of what we can calculate and
[3:07] Speaker 2: what we can actually build.
[3:09] Speaker 3: And for you listening right now, it's worth keeping this
[3:10] Speaker 3: in mind as we go along. While everyone else is
[3:12] Speaker 3: looking up at the stars, searching for aliens, or looking
[3:15] Speaker 3: at the bright, shiny objects in our solar system... Looking
[3:17] Speaker 3: at the overlooked, hidden, darkest corners might just be the
[3:20] Speaker 3: key that unlocks the secrets of our own origins. We
[3:23] Speaker 3: have to look past the celebrities of the solar system
[3:26] Speaker 3: to find the real story.
[3:27] Speaker 2: I love that phrasing, the celebrities of the solar system.
[3:30] Speaker 2: It's true. Okay, let's unpack this. Because to understand why
[3:33] Speaker 2: Calicor is so special, we first have to understand the
[3:36] Speaker 2: neighborhood it lives in. Jupiter isn't just a planet. I mean,
[3:40] Speaker 2: calling it a planet almost feels like an understatement.
[3:43] Speaker 3: It really is. It's practically its own mini solar system.
[3:46] Speaker 2: Exactly. It is a bustling, chaotic neighborhood with over 100
[3:50] Speaker 2: known moons. But the vast, vast majority of scientific funding
[3:54] Speaker 2: and public attention is completely hogged by just four of them.
[3:59] Speaker 2: The Galilean moons, Io, Europa, Ganymede, and Callisto.
[4:04] Speaker 3: And to be fair, they command that attention for a
[4:06] Speaker 3: very good reason. Discovered by Galileo in 1610, these four
[4:11] Speaker 3: moons are massive. I mean, some are even larger than
[4:14] Speaker 3: the planet Mercury. But more importantly, they are dynamic.
[4:17] Speaker 2: They've got a lot going on.
[4:18] Speaker 3: They do. They possess active geology, which completely thrills planetary
[4:22] Speaker 3: scientists because it means these worlds are alive in a
[4:24] Speaker 3: geological sense. They're constantly changing, moving and generating energy. Right.
[4:29] Speaker 2: And when we say active geology, we aren't just talking
[4:32] Speaker 2: about a few minor earthquakes or like a hot spring
[4:36] Speaker 2: here and there. We are talking about worlds that are
[4:40] Speaker 2: literally tearing themselves apart from the inside out.
[4:43] Speaker 3: Right. Oh, the violence happening on these moons is hard
[4:45] Speaker 3: to overstate. Let's just look at Io, the innermost of
[4:49] Speaker 3: the four. Io is the most volcanically active planetary body
[4:53] Speaker 3: in our entire solar system.
[4:54] Speaker 2: More than Earth.
[4:55] Speaker 3: Way more than Earth. And its activity isn't driven by
[4:59] Speaker 3: radioactive decay in its core, like ours is. Instead, it
[5:03] Speaker 3: is caught in this brutal gravitational tug of war.
[5:06] Speaker 2: Because Jupiter is so huge.
[5:08] Speaker 3: Exactly. On one side, you have the immense gravity of
[5:10] Speaker 3: Jupiter pulling it inward. But on the other side, you
[5:13] Speaker 3: have the gravity of Europa and Ganymede pulling it outward
[5:16] Speaker 3: every single time their orbits align.
[5:18] Speaker 2: So it's essentially caught in a cosmic vice.
[5:21] Speaker 3: A vice that never stops tightening and loosening. And this
[5:24] Speaker 3: creates immense tidal forces. If you imagine taking a solid
[5:27] Speaker 3: rubber ball and squeezing it, then releasing it, squeezing it,
[5:30] Speaker 3: releasing it over and over again.
[5:31] Speaker 2: It gets warm.
[5:32] Speaker 3: Right. The friction of those rubber molecules rubbing against each
[5:35] Speaker 3: other inside the ball generates heat. That exact same physical
[5:39] Speaker 3: process is happening to Io on a planetary scale. Solid
[5:42] Speaker 3: rock is being stretched and compressed by up to 100 meters.
[5:46] Speaker 3: That's over 300 feet. Every single orbit.
[5:49] Speaker 2: Wait, I just need to clarify that. The solid ground
[5:52] Speaker 2: of the moon rises and falls by 300 feet, like
[5:55] Speaker 2: the rock itself.
[5:55] Speaker 3: The rock itself flexes.
[5:57] Speaker 2: That is insane.
[5:58] Speaker 3: It is. And the internal friction from that constant flexing
[6:01] Speaker 3: generates incomprehensible amounts of heat. That heat literally melts the interior.
[6:07] Speaker 3: resulting in hundreds of active volcanoes blasting plumes of sulfur
[6:11] Speaker 3: and sulfur dioxide hundreds of miles into the vacuum of space. Wow.
[6:15] Speaker 3: The surface of Io is constantly being repaved with fresh
[6:18] Speaker 3: molten lava. It is just a world of constant violent renewal.
[6:22] Speaker 2: It sounds like an absolute nightmare world. Visually stunning, I'm sure,
[6:25] Speaker 2: but just a complete nightmare to be on. And then
[6:28] Speaker 2: on the complete opposite end of the spectrum, you have Europa,
[6:30] Speaker 2: which is sort of the darling of astrobiologists everywhere.
[6:33] Speaker 3: Oh, Europa is the great hope for finding extraterrestrial life
[6:37] Speaker 3: in our solar system right now. On the surface, it
[6:39] Speaker 3: just appears to be a barren, frozen wasteland. It's covered
[6:43] Speaker 3: in a thick crust of ice that's scarred by these
[6:45] Speaker 3: massive cracks, ridges, and chaotic terrain.
[6:48] Speaker 2: Right.
[6:49] Speaker 3: But the Galileo spacecraft data from the 1990s strongly suggested
[6:52] Speaker 3: that beneath that icy shell lies a vast global subsurface
[6:57] Speaker 3: ocean of liquid water.
[6:58] Speaker 2: And we aren't talking about a small hidden lake here.
[7:01] Speaker 2: The scale of this ocean is what always gets me.
[7:03] Speaker 3: It's massive. It is estimated that Europa's hidden ocean contains
[7:07] Speaker 3: more than twice the amount of liquid water found in
[7:09] Speaker 3: all of Earth's oceans combined.
[7:11] Speaker 2: A moon that is smaller than our own moon has
[7:13] Speaker 2: twice the liquid water of Earth. It's just a staggering thought.
[7:18] Speaker 2: And I assume that where there is that much liquid water,
[7:20] Speaker 2: there's intense interest from scientists looking for life.
[7:24] Speaker 3: Biology, at least as we understand it, requires three fundamental ingredients, right?
[7:28] Speaker 3: Liquid water, an energy source, and the right chemical building blocks.
[7:32] Speaker 2: And Europa has the water. It has the water.
[7:34] Speaker 3: It also has an energy source. The same tidal heating-warming
[7:38] Speaker 3: IO affects Europa, just to a lesser extent because it's
[7:41] Speaker 3: further away from Jupiter. But that flexing could be driving
[7:44] Speaker 3: hydrothermal vents at the bottom of its dark subsurface ocean.
[7:48] Speaker 2: Oh, like the ones we have in our deep oceans.
[7:50] Speaker 3: Exactly. If those vents exist, they could be mixing heat
[7:53] Speaker 3: and complex chemistry into the water, potentially supporting ecosystems. Entirely
[7:58] Speaker 3: independent of sunlight? Much like the vibrant communities of tube
[8:02] Speaker 3: worms and bacteria we find at deep-sea hydrothermal vents here
[8:05] Speaker 3: on Earth?
[8:06] Speaker 2: I see the appeal. I really, really do. You have
[8:08] Speaker 2: volcanoes going off on Io and massive, potentially life-harboring oceans
[8:13] Speaker 2: on Europa. It's incredibly exciting. But I see a massive
[8:16] Speaker 2: contradiction here in how we study the solar system. How so? Well,
[8:19] Speaker 2: we are pouring billions of dollars and decades of research
[8:22] Speaker 2: into these active, dynamic moons. We love them because they
[8:25] Speaker 2: are changing. Because they have volcanoes and shifting ice plates.
[8:29] Speaker 2: But if a moon is highly geologically active, if it
[8:32] Speaker 2: is constantly erupting and repaving itself with fresh lava or
[8:35] Speaker 2: cracking and refreezing fresh ice, it is constantly destroying its
[8:39] Speaker 2: own history. Oh, absolutely.
[8:40] Speaker 3: Right.
[8:41] Speaker 2: If a surface is only a few million years old
[8:42] Speaker 2: because it just got paved over yesterday, in geological time,
[8:46] Speaker 2: it can't tell us anything about what the solar system
[8:49] Speaker 2: was like four and a half billion years ago.
[8:51] Speaker 3: OK, let's unpack this because this seems like a huge
[8:53] Speaker 3: blind spot.
[8:54] Speaker 2: What's fascinating here is that you have isolated the exact
[8:58] Speaker 2: fundamental paradox that planetary historians grapple with every day. Active
[9:03] Speaker 2: geology is the great eraser of planetary history.
[9:07] Speaker 3: The great eraser. I like that.
[9:08] Speaker 2: When an instrument points at Io or Europa, it is
[9:11] Speaker 2: observing a modern, ongoing process. The material being observed has
[9:16] Speaker 2: been melted, mixed and chemically altered and recycled countless times.
[9:20] Speaker 3: It's like trying to learn about the ancient Roman Empire
[9:22] Speaker 3: by studying a modern glass and steel skyscraper in downtown Rome.
[9:26] Speaker 2: That's a perfect analogy.
[9:27] Speaker 3: The old stuff, the original foundations, they've been completely bulldozed
[9:31] Speaker 3: and built over. You can't learn about antiquity by looking
[9:34] Speaker 3: at new construction. Precisely. The original primordial material that clumped
[9:38] Speaker 3: together to form those large moons just no longer exists
[9:41] Speaker 3: in its original state. The differentiation process where the heavy
[9:45] Speaker 3: elements sink to the core and and lighter elements rise
[9:48] Speaker 3: to the crust completely destroys the pristine chemical signature of
[9:52] Speaker 3: the early solar nebula.
[9:53] Speaker 2: It cooks it out.
[9:54] Speaker 3: It does. So if the goal is to understand the
[9:57] Speaker 3: primordial soup, the original building blocks of our solar system
[10:00] Speaker 3: from the very moment of its birth, those celebrity moons
[10:03] Speaker 3: are entirely useless.
[10:05] Speaker 1: Wow.
[10:06] Speaker 2: Useless.
[10:07] Speaker 3: Historically speaking, yes, they have been permanently altered. To find pristine,
[10:12] Speaker 3: untouched samples, the focus has to shift entirely away from
[10:15] Speaker 3: the active giants and toward the wallflowers. The smaller, lesser-known
[10:19] Speaker 3: moons that have just been sitting quietly in the deep
[10:21] Speaker 3: freeze of space, completely unchanged since the epoch of formation.
[10:24] Speaker 2: The rocks that nothing ever happened to.
[10:26] Speaker 3: Exactly. The dead, quiet rocks. A lack of geological activity
[10:30] Speaker 3: is exactly what preserves the chemical and physical record. And
[10:33] Speaker 3: this requirement for absolute geological silence brings the scientific community's
[10:37] Speaker 3: focus directly onto one specific target.
[10:40] Speaker 2: All right, let's meet Calicor. We've established that we need
[10:43] Speaker 2: a small, dead rock to act as a time capsule.
[10:46] Speaker 2: I don't want to step on the numbers here, so
[10:48] Speaker 2: lay it out for us. Just how small are we
[10:51] Speaker 2: talking when we look at this particular moon?
[10:53] Speaker 3: When the measurements were finally synthesized, Calicor was determined to
[10:56] Speaker 3: have an area equivalent diameter of just 3.8 kilometers.
[10:59] Speaker 2: 3.8 kilometers. Okay, let me translate that for everyone listening.
[11:03] Speaker 2: That is about 2.4 miles across. Europa, which is the
[11:07] Speaker 2: smallest of the four famous Galilean moons, has a diameter
[11:10] Speaker 2: of over 3,100 kilometers. Calicor is a literal speck of
[11:16] Speaker 2: dust compared to Europa.
[11:17] Speaker 3: A speck.
[11:18] Speaker 2: You could comfortably walk from one end of this moon
[11:20] Speaker 2: to the other in about an hour. It's the size
[11:22] Speaker 2: of a small town or like a large neighborhood floating
[11:25] Speaker 2: out by Jupiter. But I want to pause on a
[11:27] Speaker 2: very specific phrase you just used, area equivalent diameter.
[11:30] Speaker 3: Yes.
[11:31] Speaker 2: Why did you say its diameter is 3.8 kilometers? Why
[11:33] Speaker 2: the fancy term?
[11:34] Speaker 3: Well, that phrase is a mathematical necessity because of how
[11:37] Speaker 3: gravity actually works. When an object in space accumulates enough mass,
[11:42] Speaker 3: like Earth or our moon or Europa, its own internal
[11:46] Speaker 3: gravity becomes so strong that it pulls all of its
[11:50] Speaker 3: material inward toward the center equally.
[11:52] Speaker 2: It crushes itself into a ball.
[11:54] Speaker 3: Exactly. This force molds the object into a sphere. In physics,
[11:59] Speaker 3: we call this state hydrostatic equilibrium.
[12:02] Speaker 2: So gravity is the ultimate cosmic sculptor, rounding off all
[12:05] Speaker 2: the edges. But Calicor is too small for that.
[12:07] Speaker 3: Way too small. An object with a diameter of roughly
[12:10] Speaker 3: four kilometers has virtually no gravity. There is no central
[12:14] Speaker 3: force strong enough to overcome the structural strength of the
[12:17] Speaker 3: rock itself to pull it into a neat, tidy ball.
[12:20] Speaker 2: Okay, so it just stays however it formed.
[12:21] Speaker 3: Therefore, it is highly irregular. It is lumpy, misshapen, asymmetrical.
[12:26] Speaker 3: It could be elongated like a dumbbell or jagged like
[12:29] Speaker 3: a piece of shrapnel.
[12:30] Speaker 2: So if it's not a sphere, the word diameter doesn't
[12:32] Speaker 2: really apply in the traditional sense. I mean, a dumbbell
[12:34] Speaker 2: has a different diameter depending on where you measure it, right?
[12:37] Speaker 3: And that is exactly why scientists use area-equivalent diameter. It's
[12:41] Speaker 3: a standardization technique. They calculate the total surface area of
[12:45] Speaker 3: this lumpy, irregular shape, and then they mathematically squish all
[12:49] Speaker 3: that surface area down into a perfect sphere.
[12:52] Speaker 2: Ah, good.
[12:52] Speaker 3: That theoretical sphere would be 3.8 kilometers across. It allows
[12:57] Speaker 3: researchers to compare the sizes of wildly different asymmetrical objects
[13:01] Speaker 3: on a completely level playing field.
[13:03] Speaker 2: Okay, so it is a tiny, lumpy space potato. That
[13:06] Speaker 2: makes it hard enough to find in the vastness of space.
[13:09] Speaker 2: But here's where it gets really interesting, because its size
[13:12] Speaker 2: is only half the problem. The other half is its albedo.
[13:15] Speaker 3: Yes, the albedo is the real kicker here. The geometric
[13:18] Speaker 3: albedo calculations for Calicor return a value of 0.037. Okay,
[13:21] Speaker 3: let that number.
[13:22] Speaker 2: Sink in, 0.037. The albedo scale is how we measure
[13:27] Speaker 2: brightness or reflectivity. It goes from zero, which is perfectly dark,
[13:31] Speaker 2: absorbing all light, to one, which is perfectly bright, reflecting
[13:34] Speaker 2: everything like a mirror. So 0.037 means this object reflects
[13:37] Speaker 2: only 3.7% of the light that hits it. For context,
[13:41] Speaker 2: fresh snow has an albedo of about 0.8 or 0.9.
[13:45] Speaker 2: Even a lump of charcoal has an albedo of about 0.04.
[13:49] Speaker 2: This moon, this tiny 3.8 kilometer rock, reflects less light
[13:53] Speaker 2: than a lump of barbecue charcoal.
[13:54] Speaker 3: It acts as an almost perfect light sponge, absorbing the vast,
[13:57] Speaker 3: vast majority of photons that strike its surface.
[14:00] Speaker 2: Okay, I have to push back here because it sounds
[14:02] Speaker 2: mathematically and physically impossible. You were telling me we have
[14:04] Speaker 2: a rock the size of a small town. It is
[14:07] Speaker 2: covered in material darker than asphalt, darker than charcoal, absorbing
[14:10] Speaker 2: over 96% of the sunlight that hits it. Yes. And
[14:13] Speaker 2: it is sitting out by Jupiter, which is hundreds of
[14:16] Speaker 2: millions of miles away from Earth. How is it even
[14:19] Speaker 2: physically possible for human beings to see something that small
[14:22] Speaker 2: and that incredibly dark floating in the literal abyss of space?
[14:25] Speaker 2: I mean, it's not emitting its own light. It's just
[14:27] Speaker 2: a black rock against a black background. How do you
[14:29] Speaker 2: even begin to track that?
[14:31] Speaker 3: Your skepticism is completely warranted. And honestly, it highlights the
[14:35] Speaker 3: profound technical challenge this study undertook. Observing Calicor is nothing
[14:40] Speaker 3: like looking up and seeing a star or even a planet.
[14:43] Speaker 2: Because they glow or they're huge.
[14:44] Speaker 3: Right. When you look at Jupiter through a backyard telescope,
[14:47] Speaker 3: you see it because Jupiter is massive and its thick
[14:51] Speaker 3: clouds are highly reflective. Sunlight travels from the sun, hits Jupiter,
[14:55] Speaker 3: and massive amounts of it bounce all the way back
[14:57] Speaker 3: to your eye.
[14:58] Speaker 2: It's like a giant mirror in the sky.
[14:59] Speaker 3: Exactly. But with Calicor, the sunlight out in the Jovian
[15:03] Speaker 3: system is already incredibly weak. It's only about 4% as
[15:07] Speaker 3: intense as the sunlight we feel here on Earth.
[15:10] Speaker 2: So you have super weak light hitting a super dark rock.
[15:13] Speaker 3: And of that weak light, only 3.7% manages to bounce off.
[15:17] Speaker 3: The actual number of photons, the individual particles of light
[15:20] Speaker 3: returning to Earth from Calicor, is staggeringly small. It is
[15:24] Speaker 3: barely a whisper of light against the vast, roaring glare
[15:27] Speaker 3: of Jupiter sitting right next door in our field of view.
[15:30] Speaker 2: If it's just a whisper, how do we hear it?
[15:32] Speaker 3: By throwing the absolute best, most extreme optical technology humanity
[15:37] Speaker 3: has ever developed at the problem. A standard telescope just
[15:40] Speaker 3: cannot do this. You need to combine an unprecedented level
[15:43] Speaker 3: of spatial precision with sheer brute force light gathering power.
[15:48] Speaker 2: Which brings us to the logistics of how scientists actually
[15:50] Speaker 2: cracked this mystery. The astronomical effort required to just find
[15:55] Speaker 2: this thing, let alone measure it, was monumental. This research,
[15:59] Speaker 2: led by Juan Luis Rizos and his team, required a
[16:02] Speaker 2: tag-team approach.
[16:03] Speaker 3: Very much a tag-team.
[16:05] Speaker 2: They didn't just point one big telescope to the sky.
[16:07] Speaker 2: They combined data from two entirely different types of observatories. First,
[16:12] Speaker 2: they used NASA's Hubble Space Telescope, which is obviously orbiting
[16:15] Speaker 2: high above Earth. And second, they combined that data with
[16:18] Speaker 2: the Gran Telescopio de Canarias, which is a massive multinational
[16:22] Speaker 2: telescope located on the island of La Palma off the
[16:25] Speaker 2: coast of West Africa.
[16:26] Speaker 3: It is a masterful strategy of observational astronomy. They leverage
[16:30] Speaker 3: the unique, non-overlapping strengths of two entirely different technological platforms
[16:35] Speaker 3: to solve this complex algebraic problem. Okay.
[16:38] Speaker 2: Help me understand the necessity of that coordination. Because if
[16:41] Speaker 2: Hubble is in space, flowing free from clouds, weather, and
[16:45] Speaker 2: atmospheric distortion, shouldn't Hubble just be the ultimate tool for everything?
[16:50] Speaker 2: Why do we need to coordinate with a telescope sitting
[16:53] Speaker 2: on an island off West Africa? Are they just, like,
[16:56] Speaker 2: covering for each other's blind spots?
[16:57] Speaker 3: Well, if we connect this to the bigger picture of
[17:00] Speaker 3: how telescopes actually function, the need for both becomes really clear.
[17:03] Speaker 3: Telescopes have two primary and very distinct jobs.
[17:07] Speaker 2: Okay.
[17:07] Speaker 3: The first is resolution, which is the ability to see
[17:10] Speaker 3: fine detail, to pinpoint exact locations, and to separate objects
[17:13] Speaker 3: that are very close together. The second is light gathering power,
[17:17] Speaker 3: which is the sheer ability to collect as many faint
[17:19] Speaker 3: photons as possible. Hubble is the undisputed king of resolution.
[17:23] Speaker 2: Because it's in space. The Earth's atmosphere is what makes
[17:27] Speaker 2: stars twinkle, right?
[17:27] Speaker 3: Yeah.
[17:28] Speaker 2: Which is great for poetry and romance, but absolute garbage
[17:30] Speaker 2: if you're trying to do precise astrophysics.
[17:33] Speaker 3: Exactly. The atmosphere is turbulent. Looking through it is like
[17:37] Speaker 3: trying to read a book while looking through the water
[17:39] Speaker 3: of a moving swimming pool. The light waves get bent, distorted, blurred.
[17:43] Speaker 2: That makes perfect sense.
[17:44] Speaker 3: Because Hubble is above that atmospheric pool, its vision is
[17:48] Speaker 3: crystal clear. It can pinpoint exactly where a tiny point
[17:52] Speaker 3: of light is located without any blurring. However, Hubble has
[17:56] Speaker 3: a strict physical limitation, and that is the size of
[17:59] Speaker 3: its primary mirror. Hubble's main mirror is about 2.4 meters across.
[18:04] Speaker 2: Which, to be fair, was a massive achievement to launch
[18:07] Speaker 2: into space, but tiny compared to what we can build
[18:10] Speaker 2: on the ground.
[18:11] Speaker 3: Think of a telescope mirror like a bucket left out
[18:13] Speaker 3: in a rainstorm. But instead of catching raindrops, it's catching
[18:16] Speaker 3: photons of light. Hubble has a 2.4 meter bucket. It
[18:20] Speaker 3: catches very clean, undisturbed photons, but it doesn't catch very
[18:24] Speaker 3: many of them.
[18:24] Speaker 2: Right.
[18:25] Speaker 3: Now consider the Gran Telescopio de Canarias. Its primary mirror
[18:29] Speaker 3: is a staggering 10.4 meters across.
[18:32] Speaker 2: Building a 10.4 meter mirror sounds like a total nightmare.
[18:35] Speaker 2: You can't just pour a piece of glass that big.
[18:37] Speaker 2: It would sag under its own weight, wouldn't it?
[18:39] Speaker 1: It would.
[18:39] Speaker 3: The engineering is extraordinary. It isn't a single piece of glass.
[18:44] Speaker 3: A 10.4-meter mirror would indeed deform under Earth's gravity just
[18:49] Speaker 3: from tilting it to look at the sky.
[18:51] Speaker 2: So how do they do it?
[18:52] Speaker 3: The mirror is segmented. It is made up of 36
[18:55] Speaker 3: separate hexagonal mirrors, all perfectly aligned using computer-controlled actuators that
[19:00] Speaker 3: adjust their positions hundreds of times a second to maintain
[19:02] Speaker 3: a perfect parabolic shape. The result is a massive light-gathering area.
[19:08] Speaker 3: It is a giant photon bucket.
[19:10] Speaker 2: So because Calicor is so incredibly dark, reflecting almost nothing,
[19:15] Speaker 2: Hubble's 2.4 meter bucket struggles to catch enough photons to
[19:18] Speaker 2: get a robust signal on its own, even with its
[19:21] Speaker 2: perfect vision.
[19:22] Speaker 3: Exactly. Hubble provides the absolute clarity of position, the pinpoint
[19:25] Speaker 3: accuracy of where that faint signal is coming from. But
[19:28] Speaker 3: the Gran Telescopio de Canarias, with its massive 10.4 meter mirror,
[19:31] Speaker 3: provides the brute force required to capture enough of those
[19:34] Speaker 3: rare bouncing photons to actually measure the object's brightness.
[19:37] Speaker 2: And this is where the aha moment happens for me.
[19:41] Speaker 2: Because this isn't just about taking a picture. It's about
[19:44] Speaker 2: solving a really difficult math problem. If you just see
[19:47] Speaker 2: a single faint pixel of light in a telescope, you
[19:51] Speaker 2: have a massive algebraic variable. You do. You don't know
[19:54] Speaker 2: if that faint pixel is caused by a tiny object
[19:57] Speaker 2: that is highly reflective like a small floating mirror, or
[20:01] Speaker 2: if it's caused by a massive object that is incredibly
[20:03] Speaker 2: dark like a giant mountain of coal. A small shiny
[20:06] Speaker 2: thing and a big dark thing It can look exactly
[20:09] Speaker 2: the same through a lens, right?
[20:10] Speaker 3: Yes. The degeneracy between size and albedo is one of
[20:13] Speaker 3: the classic problems in astronomy. You cannot solve for one
[20:16] Speaker 3: without knowing the other.
[20:18] Speaker 2: But by combining the telescopes, they crack it. Hubble gives
[20:21] Speaker 2: them the pinpoint spatial data, tracking its exact movement to
[20:24] Speaker 2: help calculate its mass and orbital dynamics, and then the
[20:28] Speaker 2: sheer volume of photons collected by the massive ground-based mirror.
[20:32] Speaker 2: gives them the precise photometric data needed to nail down
[20:35] Speaker 2: the brightness.
[20:36] Speaker 3: It's a perfect pairing.
[20:37] Speaker 2: You combine the two and the variables collapse. You suddenly
[20:40] Speaker 2: know exactly how big it is and exactly how dark
[20:42] Speaker 2: it is.
[20:42] Speaker 3: The synthesis of those two data sets is what allowed
[20:45] Speaker 3: Rizos and his team to strip away the ambiguity. They
[20:49] Speaker 3: didn't just guess at Kalator's properties. They definitively calculated its 3.8
[20:54] Speaker 3: kilometer size and 3.7% albedo.
[20:57] Speaker 2: It takes a global... Yeah, you have the big planet
[20:59] Speaker 2: in the middle. And the moon travels around it in
[21:02] Speaker 2: a nice, neat, perfectly circular track, usually right around the
[21:06] Speaker 2: planet's equator. The moon goes around the Earth, nice and predictable.
[21:10] Speaker 2: But Calicor's orbit is extremely non-circular. It's wildly off-kilter.
[21:16] Speaker 3: It shatters that textbook image completely. A regular moon typically
[21:20] Speaker 3: has what we call a prograde orbit, meaning it orbits
[21:23] Speaker 3: in the same direction that the host planet rotates. Furthermore,
[21:27] Speaker 3: it orbits near the planet's equatorial plane... and its orbital
[21:31] Speaker 3: path is nearly circular.
[21:32] Speaker 2: And there is a physical reason for that neatness, right?
[21:35] Speaker 3: Yes, those regular moons formed in place. When a giant
[21:38] Speaker 3: planet like Jupiter forms, it is surrounded by a massive,
[21:42] Speaker 3: swirling disk of gas and dust called an accretion disk.
[21:45] Speaker 2: Okay.
[21:46] Speaker 3: Over millions of years, the material in that disk clumps
[21:48] Speaker 3: together to form moons. Because the disk was spinning in
[21:51] Speaker 3: a specific direction around the planet's equator, the moons that
[21:55] Speaker 3: form from it also spin in that direction, on that plane,
[21:58] Speaker 3: in circular paths.
[21:59] Speaker 2: They grew up in the neighborhood, so they follow the
[22:01] Speaker 2: traffic laws of that neighborhood.
[22:02] Speaker 3: That's a great way to put it. But an irregular
[22:05] Speaker 3: moon like Calicor is a completely different beast. And the
[22:08] Speaker 3: statistics regarding these moons are often surprising to those outside
[22:11] Speaker 3: the field of astronomy. Out of the 456 currently known
[22:15] Speaker 3: moons across all the planets in our solar system, an
[22:18] Speaker 3: estimated 396 of them are irregular moons.
[22:21] Speaker 1: Wait.
[22:22] Speaker 2: Let me pause you there. 396 out of 456. That
[22:24] Speaker 2: is roughly 87%.
[22:28] Speaker 3: That proportion is accurate based on current discoveries.
[22:30] Speaker 2: So what does this all mean? If 87% of all
[22:33] Speaker 2: moons are irregular, doesn't that mean our neat, orderly textbook
[22:37] Speaker 2: diagrams of the solar system are actually a complete lie?
[22:41] Speaker 2: If the vast, overwhelming majority of moons are flying in
[22:44] Speaker 2: these chaotic, non-circular, wildly tilted orbits, then irregular is actually
[22:49] Speaker 2: the norm. Why do we even call them irregular if
[22:52] Speaker 2: they are the most common type of moon in the
[22:53] Speaker 2: solar system?
[22:54] Speaker 3: This raises an important question about nomenclature in science. And
[22:57] Speaker 3: you're right. It is highly ironic that we label them
[23:00] Speaker 3: irregular when they absolutely dominate the census of planetary satellites.
[23:04] Speaker 3: But the term does not refer to their statistical abundance.
[23:07] Speaker 3: It refers to their origin story. The regular moons are
[23:09] Speaker 3: called regular because they follow the standard rules of planetary
[23:13] Speaker 3: formation they formed in place from the primordial disk. The
[23:16] Speaker 3: irregular moons broke those rules.
[23:18] Speaker 2: Because they didn't form there.
[23:19] Speaker 3: Right. They are interlopers. They are ancient prisoners of gravity.
[23:23] Speaker 3: And you can see this in Calicor's wildly eccentric flight path.
[23:28] Speaker 3: Calicor orbits Jupiter at an average distance of about 23
[23:32] Speaker 3: million kilometers, or roughly 14.3 million miles. But that average
[23:37] Speaker 3: is heavily deceiving.
[23:38] Speaker 2: How so?
[23:39] Speaker 3: Its actual distance dramatically swings, ranging from 17.7 million kilometers
[23:44] Speaker 3: at its closest approach to Jupiter, all the way out
[23:46] Speaker 3: to 30.4 million kilometers at its furthest point.
[23:49] Speaker 2: That is a variance of over 12 million kilometers. That's
[23:52] Speaker 2: not a circular track. That is a massive, highly elliptical,
[23:56] Speaker 2: stretched out oval. It's like a chaotic pendulum swinging wildly
[23:59] Speaker 2: in and out of the Jovian system rather than a
[24:01] Speaker 2: car driving on a neat circular racetrack.
[24:04] Speaker 3: Exactly. And that extreme variance, that massive swing in orbital distance,
[24:09] Speaker 3: is the smoking gun of its origin. It tells astronomers
[24:12] Speaker 3: definitively that Calicor and moons like it were not formed
[24:17] Speaker 3: neatly in place around Jupiter. A moon cannot naturally coalesce
[24:21] Speaker 3: from a dust disk into an orbit that chaotic.
[24:24] Speaker 2: Where did they come from?
[24:25] Speaker 3: These objects were independent bodies wandering freely through the early
[24:29] Speaker 3: solar system.
[24:30] Speaker 2: Wandering around until they got too close to Jupiter. And Jupiter,
[24:32] Speaker 2: being the massive gravitational bully that it is, just snatched
[24:36] Speaker 2: them up.
[24:36] Speaker 3: Essentially, yes.
[24:38] Speaker 2: But wait, gravity alone can't capture something, can it? If
[24:42] Speaker 2: a rock flies past a planet, it'll just speed up
[24:44] Speaker 2: as it gets closer, whip around the planet, and fly
[24:47] Speaker 2: back out into space at the exact same speed, just
[24:50] Speaker 2: in a different direction. It doesn't just magically stop and
[24:53] Speaker 2: stay in orbit.
[24:54] Speaker 3: You're absolutely right. The physics of orbital capture are very specific.
[24:58] Speaker 3: You need a mechanism to bleed off kinetic energy. If
[25:00] Speaker 3: a wandering rock simply flies past Jupiter in a pure vacuum,
[25:04] Speaker 3: it will indeed just execute a hyperbolic flyby and escape
[25:07] Speaker 3: back into deep space. But billions of years ago, during
[25:10] Speaker 3: the early chaotic days of the solar system, space was
[25:14] Speaker 3: not a pure vacuum. The environment around Jupiter was still
[25:18] Speaker 3: filled with a thick envelope of primordial gas and dust.
[25:22] Speaker 2: Ah, so it wasn't empty space, it was a thick soup.
[25:24] Speaker 3: Yes. When wandering objects like Calicor plunged into that thick
[25:28] Speaker 3: gas envelope, they experienced aerodynamic drag. The friction of pushing
[25:32] Speaker 3: through that gas robbed them of their kinetic energy. It
[25:36] Speaker 3: acted like a brake.
[25:38] Speaker 2: That is so cool.
[25:39] Speaker 3: They slowed down just enough that they no longer had
[25:41] Speaker 3: the velocity to escape Jupiter's gravitational pull. The gas eventually
[25:45] Speaker 3: dissipated over millions of years, leaving these captured rocks stranded
[25:49] Speaker 3: forever in these sprawling, highly elliptical, irregular orbits.
[25:53] Speaker 2: So Calicor is literally an intact, frozen relic from the
[25:57] Speaker 2: chaotic birth of our solar system. It was an independent
[26:00] Speaker 2: world captured by gas friction and held prisoner by Jupiter
[26:03] Speaker 2: for billions of years.
[26:04] Speaker 3: That's exactly what it is.
[26:06] Speaker 2: That makes it incredibly valuable for science because it is
[26:09] Speaker 2: an untouched sample of the early solar system. But it
[26:11] Speaker 2: also makes it an absolute nightmare if you are a
[26:14] Speaker 2: mission planner trying to fly a spacecraft past it. Tracking
[26:17] Speaker 2: a wildly swinging pitch black pendulum is hard enough from Earth,
[26:21] Speaker 2: but trying to thread the needle and actually fly a
[26:24] Speaker 2: probe past it seems virtually impossible.
[26:27] Speaker 3: The navigation required is the ultimate test of interplanetary flight dynamics.
[26:31] Speaker 3: The entire purpose of this massive telescopic tag team using
[26:35] Speaker 3: Hubble and the Grand Telescopio de Canarias to precisely calculate
[26:38] Speaker 3: Calicor's orbit was specifically to prepare for a highly ambitious
[26:42] Speaker 3: flyby by the JIC spacecraft plan for October 2031.
[26:45] Speaker 2: Okay, let's look at the numbers of threading this cosmic needle,
[26:49] Speaker 2: because they are intensely stressful. Before this tracking campaign led
[26:53] Speaker 2: by RISOs, the estimated location of Kalator, where scientists thought
[26:56] Speaker 2: it would be when the JIC spacecraft arrives in 2031,
[26:59] Speaker 2: had a margin of error of about 272 kilometers. That
[27:01] Speaker 2: is about 169 miles.
[27:05] Speaker 3: Yes. And that margin of error is basically a sphere
[27:07] Speaker 3: of uncertainty. Prior to the study, we knew the rock
[27:10] Speaker 3: was somewhere inside a bubble of space 272 kilometers across. Right.
[27:14] Speaker 3: In the vastness of the solar system, that sounds tiny.
[27:17] Speaker 3: But for a spacecraft conducting a close proximity flyby, it
[27:21] Speaker 3: is a massive, highly problematic area of uncertainty.
[27:24] Speaker 2: Well, yeah. If you were trying to take a picture
[27:26] Speaker 2: of a 3.8 kilometer rock, and it could be anywhere
[27:29] Speaker 2: within a 272 kilometer bubble, you were essentially flying blind.
[27:33] Speaker 3: Completely blind.
[27:35] Speaker 2: Now, the new measurements from this telescope tag team managed
[27:38] Speaker 2: to reduce that error margin by about 80%. Wait, let
[27:41] Speaker 2: me put that in perspective and do the math for
[27:43] Speaker 2: everyone listening. Reducing a 272-kilometer margin of error by 80%
[27:48] Speaker 2: means we are stripping away about 217 kilometers of uncertainty.
[27:52] Speaker 2: That leaves us with a new, much tighter margin of
[27:54] Speaker 2: error of roughly 54 kilometers. But the data from the
[27:58] Speaker 2: European Space Agency says that the GIC spacecraft actually needs
[28:02] Speaker 2: a margin of error of about 30 kilometers or 19
[28:04] Speaker 2: miles to substantially increase its chances of successfully executing the
[28:08] Speaker 2: flyby and getting the data it needs.
[28:10] Speaker 3: Yes, 30 kilometers is the goal.
[28:12] Speaker 2: So we are at 54 kilometers of uncertainty, but the
[28:14] Speaker 2: engineers want 30. Are we still flying partially blind here?
[28:17] Speaker 3: The situation has transitioned from flying blind to flying with
[28:21] Speaker 3: severe but manageable constraints. You have to weigh risk, capability,
[28:26] Speaker 3: and the sheer scale of the dynamics at play here. Okay.
[28:30] Speaker 3: Consider the physical reality of the intercept. The GUIC spacecraft
[28:34] Speaker 3: will be moving at immense relative velocities. We are talking
[28:37] Speaker 3: about closing speeds measured in kilometers per second. It is
[28:41] Speaker 3: aiming for a target that is only 3.8 kilometers across,
[28:44] Speaker 3: covered in material darker than coal, whose position in space
[28:48] Speaker 3: swings by millions of kilometers over its orbit.
[28:51] Speaker 2: It's like standing in New York trying to photograph a
[28:53] Speaker 2: specific mosquito flying around in Los Angeles. But you only
[28:57] Speaker 2: have a one-second window to snap the picture before the
[28:59] Speaker 2: mosquito is gone forever.
[29:00] Speaker 3: That's pretty accurate, honestly. And a spacecraft's cameras and scientific
[29:04] Speaker 3: instruments have a highly restricted field of view. They act
[29:06] Speaker 3: like long telephoto lenses. If the navigation team believes the
[29:10] Speaker 3: moon is in one spot and points the cameras there,
[29:13] Speaker 3: but the moon is actually 272 kilometers to the left.
[29:16] Speaker 2: They miss it completely.
[29:17] Speaker 3: The cameras will record nothing but empty black space as
[29:20] Speaker 3: the probe zooms past. You only get one shot at
[29:23] Speaker 3: a flyby.
[29:24] Speaker 2: Because you can't hit the brakes, turn the spacecraft around
[29:27] Speaker 2: and say, let's try that again. You just whiz past
[29:30] Speaker 2: it into the void.
[29:30] Speaker 3: Right. The momentum is far too great. Now, while 54
[29:34] Speaker 3: kilometers of uncertainty isn't the 30-kilometer ideal that mission planners
[29:37] Speaker 3: dream of, achieving an 80% reduction in in error is
[29:41] Speaker 3: a monumental triumph of observational astronomy. It transforms this flyby
[29:46] Speaker 3: from a blind hope into a highly calculated game of
[29:49] Speaker 3: interplanetary billiards.
[29:51] Speaker 2: So what do they do at 54 kilometers?
[29:53] Speaker 3: At 54 kilometers of uncertainty, the navigation teams can design
[29:57] Speaker 3: sweeping camera maneuvers. They can program the spacecraft to rapidly
[30:01] Speaker 3: pan its instruments, scanning a slightly wider swath of space
[30:04] Speaker 3: during the critical seconds of closest approach. It brings a
[30:08] Speaker 3: successful October 2031 flyby out of the realm of fantasy
[30:12] Speaker 3: and firmly into the realm of true engineering possibility.
[30:15] Speaker 2: So they basically widen the net slightly, commanding the cameras
[30:18] Speaker 2: to sweep back and forth to account for the remaining
[30:21] Speaker 2: wobble in their calculations. Yeah. It's brilliant.
[30:23] Speaker 3: It's incredible engineering.
[30:25] Speaker 2: But as incredible as this Calicor intercept is... We have
[30:28] Speaker 2: to remember that this tiny dark rock is just the
[30:32] Speaker 2: appetizer for this spacecraft. The full geocision is something straight
[30:36] Speaker 2: out of a science fiction novel. Let's look at the
[30:38] Speaker 2: grand tour they have planned, because it is an exercise
[30:40] Speaker 2: in extreme patience and orbital mastery.
[30:44] Speaker 3: Oh, the timeline and the ambition of the GeoEC mission
[30:47] Speaker 3: are truly staggering.
[30:48] Speaker 2: GeoEC was launched in April 2023. It will not even
[30:53] Speaker 2: arrive in the Jupiter system until July 2031. That is
[30:57] Speaker 2: an eight-year cruise through deep space just to reach the
[31:01] Speaker 2: front door. Why does it take eight years? We've sent
[31:04] Speaker 2: probes to Jupiter much faster than that in the past.
[31:06] Speaker 3: We have, but the travel time is dictated by the
[31:08] Speaker 3: mission's ultimate destination and its need to carry massive amounts
[31:12] Speaker 3: of scientific equipment. You don't just point a rocket at Jupiter,
[31:15] Speaker 3: fire the engines, and fly in a straight line. The
[31:17] Speaker 3: rockets we have today are simply not powerful enough to
[31:20] Speaker 3: push a fully loaded, heavily shielded spacecraft like GEC directly
[31:24] Speaker 3: to the outer solar system at high speeds. Instead, orbital
[31:27] Speaker 3: mechanics requires the use of gravity assists.
[31:30] Speaker 2: Explain the physics of a gravity assist for us, because
[31:32] Speaker 2: I think it often sounds like magic to people. How
[31:35] Speaker 2: do you steal speed from a planet?
[31:38] Speaker 3: A gravity assist is essentially an exchange of orbital momentum.
[31:42] Speaker 3: Imagine you are standing on a sidewalk and a massive
[31:45] Speaker 3: truck is driving past you at 60 miles an hour.
[31:48] Speaker 2: Okay, I'm picturing it.
[31:49] Speaker 3: If you throw a tennis ball at the front of
[31:51] Speaker 3: that truck at 30 miles an hour, the ball bounces off.
[31:54] Speaker 3: But it doesn't just bounce off at 30 miles an hour.
[31:56] Speaker 3: It bounces off with its own speed, plus the forward
[31:59] Speaker 3: speed of the truck. Oh, wow. The ball comes rocketing
[32:02] Speaker 3: back at you much, much faster than you threw it.
[32:05] Speaker 2: So the ball stole kinetic energy from the truck. Did
[32:08] Speaker 2: the truck slow down?
[32:09] Speaker 3: Technically, the truck did slow down. But because the truck
[32:13] Speaker 3: is so massive compared to the tennis ball, the loss
[32:15] Speaker 3: of speed is imperceptible. In this analogy, the spacecraft is
[32:19] Speaker 3: the tennis ball, and planets like Earth and Venus are
[32:22] Speaker 3: the truck.
[32:23] Speaker 2: So GIC is bouncing off planets.
[32:25] Speaker 3: Figuratively, yes. JUICE will fly past Earth, dive toward Venus,
[32:30] Speaker 3: fly past Earth again, and use the gravitational pull of
[32:33] Speaker 3: these planets to slingshot itself. It steals a tiny fraction
[32:36] Speaker 3: of the planet's orbital momentum to build up enough velocity
[32:39] Speaker 3: to traverse the immense distance to Jupiter. It is orbital
[32:42] Speaker 3: mechanics functioning at the absolute highest level of precision.
[32:46] Speaker 2: So it bounces around the inner solar system for years,
[32:48] Speaker 2: building up speed, and finally arrives in July 2031. That
[32:53] Speaker 2: arrival perfectly sets up the Calicor flyby just a few
[32:57] Speaker 2: months later in October 2031. They hit the Dark Rock
[33:00] Speaker 2: right as they enter the system. But after that, Juice
[33:03] Speaker 2: moves on to its primary mission. The main goal is
[33:05] Speaker 2: to study the massive icy Galilean moons to ascertain if
[33:08] Speaker 2: they host conditions habitable for life. We were back to Europa, Callisto,
[33:13] Speaker 2: and Ganymede.
[33:14] Speaker 3: And the instruments on board are specifically designed for this task.
[33:17] Speaker 3: While Calicor offers a look at the dead past, the
[33:20] Speaker 3: icy moons offer a look at potential biology. JUICE is
[33:23] Speaker 3: equipped with ice-penetrating radar, laser altimeters, and highly sensitive magnetic
[33:27] Speaker 3: field sensors. These are designed to peer through miles of
[33:31] Speaker 3: solid ice, mapping the depth, the salinity, and the composition
[33:35] Speaker 3: of those hidden global oceans.
[33:37] Speaker 2: But the absolute grand finale of this mission, the mic
[33:40] Speaker 2: drop moment for the European Space Agency, doesn't happen until
[33:43] Speaker 2: December 2034. That is when Juicy will actually alter its
[33:48] Speaker 2: trajectory and enter orbit around Ganymede, not Jupiter. It will
[33:52] Speaker 2: orbit the moon Ganymede itself. And when it does that,
[33:55] Speaker 2: it will become the first spacecraft in human history to
[33:58] Speaker 2: orbit a moon other than Earth's own moon.
[34:00] Speaker 3: Achieving orbital insertion around a moon of another planet is
[34:03] Speaker 3: a monumental milestone in space exploration.
[34:06] Speaker 2: Never been done.
[34:07] Speaker 3: Never. And Ganymede is a fascinating world in its own right.
[34:10] Speaker 3: It is the largest moon in the solar system. It's
[34:12] Speaker 3: actually larger than the planet Mercury. More importantly, it is
[34:15] Speaker 3: the only moon in the solar system now to generate
[34:18] Speaker 3: its own internal magnetic field, driven by a churning liquid
[34:21] Speaker 3: iron core, much like Earth's.
[34:23] Speaker 2: But wait, Juicy arrives at Jupiter in 2031, but doesn't
[34:27] Speaker 2: orbit Ganymede until 2034. Why does it take three years
[34:31] Speaker 2: just to park around a moon once you are already
[34:33] Speaker 2: in the neighborhood?
[34:34] Speaker 3: It is because the environment around Jupiter is incredibly hostile,
[34:37] Speaker 3: and orbital mechanics require a delicate, grueling dance. Jupiter's massive
[34:42] Speaker 3: magnetic field acts like a giant particle accelerator.
[34:45] Speaker 2: Oh, the radiation.
[34:46] Speaker 3: Intense radiation. It traps highly charged particles that are intensely
[34:51] Speaker 3: destructive to spacecraft electronics. If JUICE just flew directly to
[34:55] Speaker 3: Ganymede and tried to stop, it would require too much
[34:58] Speaker 3: fuel and it would be heavily exposed to this radiation.
[35:00] Speaker 2: So it has to weave its way in.
[35:01] Speaker 3: Exactly. It will spend those three years executing dozens of
[35:05] Speaker 3: complex flybys of Europa, Callisto, and Ganymede, using their gravity
[35:08] Speaker 3: to slowly, methodically alter its trajectory and bleed off velocity.
[35:13] Speaker 2: Just kept bouncing around the moons.
[35:15] Speaker 3: It is a grueling, radiation-soaked orbital dance. It has to
[35:19] Speaker 3: survive the radiation belts dipping in and out until its
[35:21] Speaker 3: speed perfectly matches Ganymede's, allowing it to finally be captured
[35:25] Speaker 3: by the moon's gravity in 2034.
[35:27] Speaker 2: Over a decade of absolute patience, from a 2023 launch
[35:31] Speaker 2: to a 2034 orbital insertion, dodging radiation and threading cosmic needles.
[35:38] Speaker 2: I have to ask, how does a single mission effectively
[35:41] Speaker 2: balance these two incredibly distinct goals? I mean, on one hand,
[35:45] Speaker 2: you have astrobiology, the hunt for habitability and liquid oceans
[35:49] Speaker 2: on the massive icy moons. On the other hand, you
[35:51] Speaker 2: have ancient history, the flyby of a tiny, dead, pitch
[35:55] Speaker 2: black rock like Calicor. They seem like completely different fields
[35:59] Speaker 2: of science crammed onto one robot.
[36:01] Speaker 3: Well, if we connect this to the bigger picture, this
[36:04] Speaker 3: dual approach beautifully synthesizes the ultimate questions of humanity. The
[36:08] Speaker 3: two goals are not opposed at all. They're deeply complementary.
[36:10] Speaker 3: You cannot fully understand the present potential for life in
[36:14] Speaker 3: a solar system without understanding the raw materials that are
[36:17] Speaker 3: available when that solar system formed and evolved.
[36:19] Speaker 2: You have to know the ingredients of the cake before
[36:21] Speaker 2: you can understand how it baked.
[36:22] Speaker 3: Exactly. On one hand, investigating Ganymede in Europa is a
[36:25] Speaker 3: search focused on the future, the potential for biology, the
[36:28] Speaker 3: study of active dynamic environments. On the other hand, the
[36:32] Speaker 3: flyby of Calicor is a profound look into the deep
[36:35] Speaker 3: foundational past. It reveals the chemical baseline. By capturing both
[36:40] Speaker 3: ends of the spectrum, the primordial building blocks and the complex,
[36:43] Speaker 3: potentially habitable modern world's juice is providing a comprehensive start-to-finish
[36:49] Speaker 3: narrative of our cosmic neighborhood.
[36:51] Speaker 2: It's all connected.
[36:51] Speaker 3: It really is. Orbiting Ganymede in 2034 will undeniably be
[36:55] Speaker 3: a monument to human engineering, changing our relationship with the
[36:59] Speaker 3: cosmos by proving we can navigate and reside in the
[37:02] Speaker 3: complex orbital mechanics of another planet's satellite system.
[37:06] Speaker 2: It is the complete story of us, of the chaotic
[37:08] Speaker 2: birth of the solar system represented by the dark, battered
[37:11] Speaker 2: pebble of Calicor and the complex, watery, potentially life-harboring present
[37:15] Speaker 2: represented by the giant icy moons. I want to thank
[37:19] Speaker 2: you listening right now for coming on this incredible journey
[37:22] Speaker 2: with us today through the Jupiter system. We've gone from
[37:24] Speaker 2: the blazing, sulfur-spewing volcanoes of Io to the dark, stealthy,
[37:28] Speaker 2: ancient surface of Calicor.
[37:30] Speaker 3: It's a vast neighborhood.
[37:31] Speaker 2: Truly vast. And we've seen how hundreds of scientists and
[37:35] Speaker 2: engineers are pushing the absolute limits of optical technology, building
[37:39] Speaker 2: massive 10.4 meter mirrors on Earth and crunching orbital math
[37:43] Speaker 2: just to catch a fleeting glimpse of a rock the
[37:45] Speaker 2: size of a small town millions of miles away.
[37:48] Speaker 3: The persistence required to execute a mission like this is
[37:51] Speaker 3: a testament to human curiosity. We simply refuse to leave
[37:54] Speaker 3: the dark corners unexplored, no matter how difficult the physics
[37:57] Speaker 3: or the engineering become.
[37:59] Speaker 2: And as we wrap up, I want to leave you
[38:01] Speaker 2: with a lingering thought to mull over. We spend so
[38:04] Speaker 2: much of our time, so much of our funding, and
[38:06] Speaker 2: so much of our collective human imagination looking for alien
[38:09] Speaker 2: life on places like Europa. We're constantly looking forward to
[38:13] Speaker 2: what could be out there, focusing heavily on the potential
[38:15] Speaker 2: of the future. But in doing so, in focusing so
[38:18] Speaker 2: intensely on the bright, active, sparkling worlds that dazzle our instruments,
[38:22] Speaker 2: we risk flying right past the very object that tells
[38:25] Speaker 2: us exactly where we came from. If an object as small,
[38:28] Speaker 2: as dark, and as fragile as Calicor has managed to
[38:30] Speaker 2: survive perfectly intact, silently orbiting in the dark since the
[38:34] Speaker 2: very dawn of the solar system? What other tiny, pitch-black
[38:37] Speaker 2: time capsules are silently waiting out there in the deep void,
[38:40] Speaker 2: holding the ultimate secrets of our origins, just waiting for
[38:43] Speaker 2: us to finally build a telescope big enough to notice them?

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