Speaker 1: Welcome to Bedtime Astronomy. Explore the wonders of the cosmos
Speaker 1: with our soothing Bedtime Astronomie podcast. Each episode offers a
Speaker 1: gentle journey through the stars, planets, and beyond, perfect for
Speaker 1: unwinding after a long day. Let's travel through the mysteries
Speaker 1: of the universe as you drift off into a peaceful
Speaker 1: slumber under the night sky.
Speaker 2: Welcome Today, we are peering through the invisible really to
Speaker 2: understand just how enormous and maybe how fragile our planet's
Speaker 2: atmospheric bubble actually is.
Speaker 3: Quite something.
Speaker 2: Yeah, forget that clean, neat blue line you see in
Speaker 2: photos from space. Earth is actually well hiding this truly
Speaker 2: massive dynamic halo of gas, right, and it stretches what
Speaker 2: a million miles out into the cosmos.
Speaker 3: It's an astounding concept. Really. It fundamentally redefines where we
Speaker 3: think our planet ends. Yeah, we're used to thinking of
Speaker 3: the atmosphere stopping neatly, you know, maybe a few hundred
Speaker 3: miles up in the thermosphere. Sure, but this outer layer,
Speaker 3: often called the geo corona, that's our true sprawling frontier.
Speaker 3: And now, for the first time, NASA is dedicating a
Speaker 3: mission solely to understanding it, and that's.
Speaker 2: Our mission today. We're going to unpack the story and
Speaker 2: the scientific promise behind the Carruthers Geocrona Observatory or CGO.
Speaker 2: This isn't just about taking pictures. It's about getting the
Speaker 2: first continuous, comprehensive movies of this dynamic invisible layer of
Speaker 2: the atmosphere.
Speaker 3: Real time dynamics.
Speaker 2: We've got a whole stack of sources detailing the history,
Speaker 2: the discovery, the really cutting edge tack involved, and what
Speaker 2: it all means scientifically.
Speaker 3: And this knowledge it matters profoundly to you listening. Yeah,
Speaker 3: this is really your shortcut to understanding the complex environment
Speaker 3: of near Earth space. It has huge implications like what
Speaker 3: well it impacts everything from how we predict dangerous space weather,
Speaker 3: you know, the stuff that threatens satellites, even our infrastructure
Speaker 3: on the ground. Okay, and maybe most immediately, how we
Speaker 3: protect the Artemis astronauts. They'll soon be traveling right through
Speaker 3: this region on their way to the Moon.
Speaker 2: Right through this invisible halo exactly.
Speaker 3: So we're going to map Earth's invisible reach and explain
Speaker 3: why it really governs our cosmic future in some important ways.
Speaker 2: Okay, let's unpack this. We should probably start with the basics,
Speaker 2: the fundamental physics. We've used a couple of big terms already,
Speaker 2: the exosphere and the geo corona, right before we dive
Speaker 2: into the new mission itself, which sounds like an engineering marvel.
Speaker 2: We need to know what this invisible barrier actually is,
Speaker 2: what's it made of? How does it stretch so darn far?
Speaker 3: Absolutely, the exosphere is the key thing here. Structurally speaking.
Speaker 3: It is the outermost layer, really the most tenuous layer
Speaker 3: of our atmosphere.
Speaker 2: How far up does it start?
Speaker 3: It starts roughly three hundred to maybe six hundred miles up.
Speaker 3: It varies a bit, depends on solar activity. Okay, think
Speaker 3: of it as the boundary zone. It's where the atmosphere
Speaker 3: just gradually, almost chaotically, dissipates into the vacuum of interplanetary space.
Speaker 2: So we're talking way above the International Space Station, way
Speaker 2: above most low Earth satellite.
Speaker 3: Oh yeah, much higher.
Speaker 2: If it's so diffuse, so thin, what's actually in it?
Speaker 2: Is it just like a random mix of gases that floated.
Speaker 3: Up mostly No. Theorists figured this out a long time ago,
Speaker 3: and we've confirmed it now. It's overwhelmingly made. The lightest
Speaker 3: element there is neutral hydrogen.
Speaker 2: Atoms just hydrogen. Why hydrogen?
Speaker 3: Well, because the atmosphere gets progressively hotter as you go
Speaker 3: up through the thermosphere right right, So the atoms way
Speaker 3: up at this altitude, they get really energized. They're moving
Speaker 3: at extreme speeds.
Speaker 2: Ah. So this sounds like that process thermal escape, where
Speaker 2: things get so hot and move so fast they can
Speaker 2: just overcome gravity.
Speaker 3: That's exactly the mechanism. Hydrogen atoms are incredibly light, so
Speaker 3: light that when they reach the exosphere, their thermal velocity
Speaker 3: their speed is often high enough to actually exceed Earth's
Speaker 3: escape velocity.
Speaker 2: They can just leave.
Speaker 3: They can just leave. I mean, these individual atoms are
Speaker 3: traveling in these chaotic, ballistic paths. Some fall back towards
Speaker 3: Earth's sure, but many escape entirely. They just slowly bleed
Speaker 3: off into interplanetary space. It's happening constantly.
Speaker 2: Wow. Okay, So if it's just individual hydrogen atoms floating around,
Speaker 2: really spread out, why can't we see it. You call
Speaker 2: it a halo, which makes me think of light. But
Speaker 2: you also said it's invisible.
Speaker 3: Right, good question. That's where the geocrona comes in. The
Speaker 3: geocrona is basically the invisible light show that reveals the shape,
Speaker 3: the density, and the extent of the exosphere. Ok, it's
Speaker 3: a faint halo, but it's made of ultraviolet light UV
Speaker 3: light specifically, it's radiation caused by sunlight interacting with those
Speaker 3: hydrogen atoms solar lime and alpha light.
Speaker 2: To be precise, liman alpha, that's the characteristic spectral line
Speaker 2: of hydrogen, isn't it exactly?
Speaker 3: So when the hydrogen atoms way out there in the
Speaker 3: exosphere get hit by this liman alpha radiation coming from
Speaker 3: the Sun, they absorb that energy for a split second,
Speaker 3: and then they immediately rea or scatter that same UV
Speaker 3: photon ah, like a tiny echo sort of. Yeah, And
Speaker 3: this scattering process creates a measurable glow, but it's incredibly faint,
Speaker 3: and it's in the UV spectrum, which our eyes can't see.
Speaker 2: So that faint UV glow is the geo corona.
Speaker 3: That's the geo corona, and you need very specialized instruments
Speaker 3: UV cameras to actually map its shape and monitor how
Speaker 3: it changes over time.
Speaker 2: So we've got this enormous escaping cloud of hydrogen that's
Speaker 2: the exosphere, and it's revealed only by its faint UV glow.
Speaker 2: That's the Geo Corona.
Speaker 3: You got it.
Speaker 2: What's fascinating, though, is that even before this brand new mission,
Speaker 2: scientists kind of knew the Geo Corona was hiding this
Speaker 2: massive secret about how big our atmosphere really is.
Speaker 3: That's right before cgo, the new NASA effort, we had
Speaker 3: very little comprehensive data, just snapshots. Really, scientists could only speculate,
Speaker 3: sometimes wildly, about how far the atmosphere truly extended, what were.
Speaker 2: The boundaries, how did it all work internally exactly?
Speaker 3: And that uncertainty was entirely rooted in the fact that
Speaker 3: we can couldn't see it clearly, not from Earth, not
Speaker 3: even from low Earth orbit. You really need to get
Speaker 3: outside the halo to properly measure the.
Speaker 2: Halo, which brings us perfectly to a moment in space
Speaker 2: history that's absolutely fundamental here. It's why this new observatory
Speaker 2: is needed, and it explains the name we have to
Speaker 2: talk about. The pioneer, doctor George Carruthers.
Speaker 3: Yes, doctor Carruthers, a brilliant physicist and engineer. He really
Speaker 3: dedicated his career to developing these highly specialized untraviolet cameras
Speaker 3: needed to see the GEO Corona.
Speaker 2: He was instrumental, wasn't it, and showing that we could
Speaker 2: actually map this incredibly faint UV light and get meaningful
Speaker 2: data from it.
Speaker 3: Absolutely, and the sources make clear this wasn't an overnight thing.
Speaker 3: He didn't just sketch the final instrument on a napkin. No,
Speaker 3: he had to launch prototypes first on sounding rockets, test rockets.
Speaker 3: It was a methodical, step by step process of refining
Speaker 3: the technology needed to capture this specific kind of light
Speaker 3: that nobody had really imaged well before.
Speaker 2: It sounds like a huge technical challenge. UV light is
Speaker 2: gets absorbed.
Speaker 3: Easily, tremendous challenge. UV is easily absorbed by normal glass,
Speaker 3: even by the thin atmosphere itself if you're too close.
Speaker 3: So building a working camera meant dealing with vacuum technology,
Speaker 3: unique materials for lenses and detectors, really pushing the envelope.
Speaker 2: And all that were culminated in this pivotal moment in
Speaker 2: April nineteen seventy two during the Apollo sixteen mission.
Speaker 3: That's the one people think of Apollo from moon rocks geology.
Speaker 3: Mostly yeah, but this was a key scientific experiment that
Speaker 3: had nothing directly to do with the moons. Surface itself.
Speaker 2: What did they do?
Speaker 3: As part of their lunar surface activities? The Apollo sixteen
Speaker 3: astronauts John Young and Charles Duke set up Coruther's specially
Speaker 3: developed camera. It was called the far UV Camera Spectrograph.
Speaker 3: Right did they put it right there on the Moon
Speaker 3: in the Descartes Highlands region? Wow?
Speaker 2: So this was it, This instrument sitting on the Moon's
Speaker 2: surface looking back at Earth. It gave humanity our first direct,
Speaker 2: clear glimpse of the GEO Corona mapped against the blackness
Speaker 2: of space.
Speaker 3: The images were historic, groundbreaking.
Speaker 2: It sounds like a total scientific triumph. But you said
Speaker 2: earlier there was a twist. This is where it gets
Speaker 2: really interesting.
Speaker 3: Right.
Speaker 2: The images were stunning, but they also revealed a massive
Speaker 2: problem with how we understood the atmosphere's scale exactly.
Speaker 3: The finding was so unexpected that Laura Waldrop, who's the
Speaker 3: principal investigator for the new CGEO mission, she described those
Speaker 3: original Apollo sixteen results as really shocking.
Speaker 2: Shocking. Why shocking? What did they see or not see?
Speaker 3: Well? The shock was that the camera, even though it
Speaker 3: was way out there on the Moon, wasn't actually far
Speaker 3: into a way to capture the entire Geo corona in
Speaker 3: its field of view.
Speaker 2: Wait, seriously, the camera on the Moon was too close.
Speaker 3: Too close. They discovered that the camera was sitting inside
Speaker 3: this massive atmosphere kalo itself. Yes, this light, fluffy cloud
Speaker 3: of hydrogen extended much much farther from Earth's surface than
Speaker 3: any existing theory, any model had predicted up to that point.
Speaker 2: That is, that's an incredible thought. We sent a camera
Speaker 2: a quarter of a million miles away to the Moon,
Speaker 2: thinking we get a good look from the outside, and
Speaker 2: we realized we were still basically swimming in Earth's atmosphere.
Speaker 2: That just tells you everything about the scale we were underestimating.
Speaker 3: It completely blew the existing theories out of the water.
Speaker 2: Uh huh.
Speaker 3: They were proven incomplete instantly. Before Apollo sixteen, atmospheric models
Speaker 3: were pretty conservative about.
Speaker 2: The upper limits, and after.
Speaker 3: Based on that initial nineteen seventy two data, the scientific
Speaker 3: consensus had to shift dramatically. The exosphere. This hydrogen halo
Speaker 3: is now thought to stretch at least halfway to the Moon.
Speaker 2: Halfway, so that's nearly one hundred and twenty thousand.
Speaker 3: Miles out at a minimum. It's huge.
Speaker 2: So this is why the new mission is absolutely vital.
Speaker 2: Apollo sixteen give us this shocking snapshot proved it was massive.
Speaker 2: But the new Corruther's Geocrona Observatory is designed to finally
Speaker 2: show us how this gigantic structure moves, how it changes
Speaker 2: over time, the dynamic.
Speaker 3: That's the perfect analogy. It's the difference between looking at
Speaker 3: a single photograph of a river versus on watching a
Speaker 3: continuous high resolution movie of its currents, its eddies, its floods,
Speaker 3: its flow patterns.
Speaker 2: Seeing the whole system in action exactly.
Speaker 3: And it's really fitting that this modern mission, designed to
Speaker 3: finally capture the full scope the dynamics of this region,
Speaker 3: is named in honor of doctor Carruthers, the scientists who
Speaker 3: first proved it existed and showed us just how enormous
Speaker 3: it truly was.
Speaker 2: Okay, let's shift gears. Then let's talk about the engineering
Speaker 2: and the orbital mechanics of this new mission. If the
Speaker 2: Apollo sixteen camera on the Moon was too close, where
Speaker 2: does the Coruthers Geocorna Observatory CGO need to go to
Speaker 2: get that complete view?
Speaker 3: It needs to get far away, much much farther than
Speaker 3: the Moon. The CGO spacecraft itself it's relatively compact, the
Speaker 3: sources say about five hundred and thirty one pounds, roughly
Speaker 3: the size of a love seat sofa.
Speaker 2: A scientific love seat floating way out there pretty much.
Speaker 3: But its destination is the absolutely critical part.
Speaker 2: So what's its main job out there?
Speaker 3: Its primary goal is capture those first continuous movies of
Speaker 3: Earth's entire exosphere, reveal not just its overall size, but
Speaker 3: its complex internal dynamics.
Speaker 2: Like how the hydrogen atoms get accelerated, where they escape from,
Speaker 2: how the solar wind pushes them.
Speaker 3: Around precisely that continuous full disc view showing change over time.
Speaker 3: That's the data we've literally never had before.
Speaker 2: And the launch itself is interesting. CGO isn't going up alone,
Speaker 2: is it. It's part of a bigger package deal, which
Speaker 2: kind of speaks to its strategic importance in understanding the
Speaker 2: whole solar environment.
Speaker 3: That's right. It's launching fingers crossed for the schedule no
Speaker 3: earlier than Tuesday, September twenty third, from NASA's Kennedy Space
Speaker 3: Center aboard of SpaceX Falcon nine rocket, and it is
Speaker 3: launching alongside two other incredibly critical missions. It's a trio
Speaker 3: heading out together, creating this powerful synergistic observing platform.
Speaker 2: Okay, walk us through the companions. Who else is hitching
Speaker 2: a ride and how do they connect to CGO.
Speaker 3: So launching the CGO, we have NASA's IMAP, that's the
Speaker 3: Interstellar Mapping and Acceleration Probe and NOAA's sd WFO L
Speaker 3: one satellite. SWFO stands for Space Weather follow on and
Speaker 3: the L one tells you the destination.
Speaker 2: Ah, so all three are headed for the same spot exactly.
Speaker 3: They're all heading toward the same very strategic destination point
Speaker 3: in space.
Speaker 2: Lagrange point one lagarannge point one L one. Let's pause there,
Speaker 2: because that location is key hy L one. What makes
Speaker 2: it so special gratationally that it's the only practical place
Speaker 2: for CGO to get this view.
Speaker 3: L one is crucial because it directly addresses that core
Speaker 3: lesson from a poly sixteen. You need distance and you
Speaker 3: need stability. L one is this specific gravitationally balanced point
Speaker 3: in space.
Speaker 2: Where is it.
Speaker 3: It's positioned about one million miles from Earth, but closer
Speaker 3: to the Sun along the Sun Earth.
Speaker 2: Line one million miles. Okay, that's roughly four times farther
Speaker 2: away than the Moon exactly.
Speaker 3: And that distance finally, gives CGO the clear, unobstructed field
Speaker 3: of view it needs to capture the entire geo corona
Speaker 3: without being inside it.
Speaker 2: And why is it stable? What does lagrange point mean?
Speaker 3: Okay, So L one is one of five special points
Speaker 3: in the Sun Earth system where the gravitational pulls of
Speaker 3: the Sun and the Earth plus the centrifugal force of
Speaker 3: orbiting all balance out almost.
Speaker 2: Perfectly, like a gravitational saddle point.
Speaker 3: Kind of Yeah, So placing a spacecraft there means it
Speaker 3: can stay relatively stationary with respect to Earth, using minimal
Speaker 3: fuel for station keeping. It effectively orbits the Sun with
Speaker 3: the Earth, but staying in that balance spot ahead of us.
Speaker 2: So it offers this continuously stable, unhindered viewpoint looking back
Speaker 2: at Earth, always seeing the sunlit side without Earth ever
Speaker 2: blocking the view.
Speaker 3: That continuous stable perspective is the key. It avoids all
Speaker 3: the scattered light issues and background interference that hampered the
Speaker 3: Apollo sixteen view, and it allows for uninterrupted monitoring of
Speaker 3: how the geocrona reacts to things coming from the Sun.
Speaker 2: How long does it take to get there?
Speaker 3: The cruise phase to reach L one is about four months,
Speaker 3: and this is maybe a one month checkout period once.
Speaker 2: It arrives and then the science starts.
Speaker 3: Then the primary science phase begins, planned for March twenty
Speaker 3: twenty six, and it's set to last for at least
Speaker 3: two years.
Speaker 2: Okay, now let's look back to those co launching partners
Speaker 2: IMAPP and SWFOL one. Why are they necessary neighbors for
Speaker 2: CGO at L one. If CGO is watching the atmospheric response,
Speaker 2: what are IMAP and SWFOL one doing measuring the cause?
Speaker 3: It's a perfect setup for cause and effects science. SWFOL
Speaker 3: one being right there between the Sun and Earth at
Speaker 3: L one, its main job is to steer at the
Speaker 3: Sun looking for trouble exactly, monitoring solar flares, watching for
Speaker 3: coronal mass ejections CMEs. It's designed to provide crucial early warnings,
Speaker 3: sometimes hours before those energetic particles or plasma clouds actually
Speaker 3: arrive at Earth. It's NAA's frontline space weather outpost.
Speaker 2: So SWFAL one is the warning system. It measures the
Speaker 2: incoming energy blast correct.
Speaker 3: IMAPP, meanwhile, is a bit different. It's designed to study
Speaker 3: the more fundamental physics of the heliosphere. That's the giant
Speaker 3: magnetic bubble created by the Sun that involves the solar system.
Speaker 2: How particles get accelerated by the Sun, and how the
Speaker 2: solar wind works.
Speaker 3: That kind of stuff, right, how the solar wind interacts
Speaker 3: with the interstellar medium beyond our system. It measures the
Speaker 3: fundamental properties of the solar wind itself, the magnetic feels
Speaker 3: the cosmic rays constantly bombarding us. It's looking at the
Speaker 3: ambient conditions in the particle physics.
Speaker 2: Okay, So SWFOL one sees the big eruptions coming. IM
Speaker 2: measures the details of the particles and fields within those eruptions,
Speaker 2: and just the general solar wind. And then CGO takes
Speaker 2: the baton. It watches how Earth's tenuous exosphere, our outermost boundary,
Speaker 2: reacts in real time to those measured inputs from its neighbors.
Speaker 3: Precisely, that systematic view lets scientists directly connect the dots.
Speaker 3: Here's the solar event from SWFOO one. Here are the
Speaker 3: properties of the particles hitting us from IM, and here's
Speaker 3: exactly how the geocorna responded. From CGO.
Speaker 2: It creates this incredibly comprehensive picture of space weather, doesn't
Speaker 2: it From the eruption source, through its journey across space
Speaker 2: right to its impact on our planet's boundary layer.
Speaker 3: It maximizes the scientific return for all three missions. They
Speaker 3: really complement each other perfectly. Now.
Speaker 2: To actually capture these continuous movies from L one, CGO
Speaker 2: uses two main instruments, right, both specialize UV cameras, but
Speaker 2: they work together.
Speaker 3: Yes, two cameras designed to cover both the close in
Speaker 3: action near Earth and the vast far out scope simultaneously.
Speaker 3: They look at slightly different things.
Speaker 2: Okay, what's the first one.
Speaker 3: The first is the Near Field Imager. As the name suggests,
Speaker 3: this camera is optimized to look closer to the planet.
Speaker 3: It uses a specific range of UV wave of length
Speaker 3: suited for that region.
Speaker 2: The mission scientist said, it lets them zoom up really close.
Speaker 2: What are they looking for right near the planet? Isn't
Speaker 2: the main action way out?
Speaker 3: Well, they need to see the source dynamics too. The
Speaker 3: Near Field Imager focuses on how the exosphere is varying
Speaker 3: closer in, where is the hydrogen coming from, maybe from
Speaker 3: water molecules breaking down lower down? What are the initial
Speaker 3: escape processes?
Speaker 2: Ah tracking atoms just starting their journey or maybe falling
Speaker 2: back Exactly.
Speaker 3: It requires different optical properties because the UV light scatter
Speaker 3: is actually denser closer to Earth, so you need to
Speaker 3: filter image that differently than the really faint stuff way out.
Speaker 2: Okay, so that's the close up view, then there must
Speaker 2: be the wide field imager. Is that the one designed
Speaker 2: to solve the Apollo sixteen problem seeing the.
Speaker 3: Whole picture precisely? The wide field imager is built with
Speaker 3: a much larger field of view. It lets them see
Speaker 3: the full scope and expanse of the exosphere, as they
Speaker 3: put it, and crucially, crucially, how that whole hydrogen cloud
Speaker 3: is changing far far away from Earth's surface, out where
Speaker 3: the atoms are truly making their escape, where the interaction
Speaker 3: with the solar wind is most direct. That's the region
Speaker 3: Apollo sixteen showed us was so unexpectedly huge.
Speaker 2: So by using different UV wavelengths, different sensitivities, different fields
Speaker 2: of view, these two imagers together will map not just
Speaker 2: where the hydrogen is right, but also things like its velocity,
Speaker 2: the direction is traveling, the rate at which it's escaping
Speaker 2: as it moves through the geo corona and out into space.
Speaker 3: That's the goal to get the full forty picture three
Speaker 3: D space plus time, which.
Speaker 2: Brings us finally to the really big so what question. Okay,
Speaker 2: we map the dynast of this million mile long hydrogen
Speaker 2: halo in exquisite detail. What does that actually do for
Speaker 2: us here on Earth and maybe even beyond.
Speaker 3: Well, the most immediate, you could say life critical relevance
Speaker 3: of this mission is space weather forecasting and tied to
Speaker 3: that planetary protection.
Speaker 2: Right, which is why it's launching with NOAA's dedicated space
Speaker 2: weather satellite SWFOL one exactly.
Speaker 3: We often talk about solar flares or CMEs reaching Earth,
Speaker 3: causing those beautiful auroras, but also potentially knocking out power
Speaker 3: grids or damaging satellites. Yeah, but we have to remember
Speaker 3: those eruptions, that blast of energy and particles, it hits
Speaker 3: the exosphere, in the ionosphere first, that's the front line
Speaker 3: it is, and.
Speaker 2: The exosphere acts as our first line of defense or
Speaker 2: maybe more like the first point of contact.
Speaker 3: Yeah, maybe point of contact is better. When those highly
Speaker 3: energized particles from the Sun slam into those hydrogen atoms
Speaker 3: and the geo corona, it triggers this complex chain reaction
Speaker 3: that energy cascades downwards, eventually causing those dangerous geomagnetic storms
Speaker 3: closer to the ground.
Speaker 2: So understanding how the exosphere initially reacts, does it compress,
Speaker 2: does it expand does it channel that energy differently depending
Speaker 2: on the storm. That's essential for making better predictions.
Speaker 3: It's absolutely essential for refining the forecast models. If we
Speaker 3: know the state of the geocurana before the storm hits
Speaker 3: and we see how it responds initially, we can predict
Speaker 3: the downstream effects much more accurately.
Speaker 2: And this connects directly to human exploration, doesn't it. You
Speaker 2: mentioned Artemis, this is a core requirement for protecting those astronauts.
Speaker 3: It really is. When astronauts travel beyond Earth's protect magnetic field,
Speaker 3: which they do on the way to the Moon or Mars,
Speaker 3: they are far more vulnerable to intense bursts of radiation
Speaker 3: from severe space weather events.
Speaker 2: That journey to the Moon takes several days. They need
Speaker 2: highly accurate real time forecasts to know if a big
Speaker 2: solar particle event is coming, so they know when to
Speaker 2: shelter inside the most shielded parts of their spacecraft.
Speaker 3: Exactly. Knowing the density, the structure, the dynamics of the
Speaker 3: the exosphere, which is what CGO will map continuously, helps
Speaker 3: make those radiation predictions much more reliable. It provides better
Speaker 3: input data for the complex models that forecast radiation exposure levels.
Speaker 2: So if we can accurately forecast that initial atmospheric reaction cgoces.
Speaker 3: We give the crews a much safer transit window for
Speaker 3: traveling to the Moon and eventually for future Mars missions too.
Speaker 3: It's about managing risk.
Speaker 2: Okay, so astronaut safety is paramount, But let's pivot to
Speaker 2: the second big science goal, this whole atmospheric escape process.
Speaker 2: You mentioned hydrogen is a building block of water ho
Speaker 2: So when CGO maps escaping hydrogen, are we fundamentally talking
Speaker 2: about understanding how Earth holds onto its water over geological time,
Speaker 2: or maybe how it slowly loses it.
Speaker 3: That's precisely what we're getting at, and for me, this
Speaker 3: is one of the most exciting aspects of cgeoscience. When
Speaker 3: we map the precise rate the mechanisms of hydrogen escape today,
Speaker 3: we are shedding light on this absolutely crucial planetary question.
Speaker 3: Why does Earth have oceans? Why does it retain vast
Speaker 3: amounts of water while other seemingly similar planets like Mars
Speaker 3: or maybe even Venus, appear to have lost most of
Speaker 3: airs over billions of years.
Speaker 2: It's that fundamental planetary struggle, isn't it between keeping your
Speaker 2: water and having it stripped away or leak out.
Speaker 3: It is. We think Mars was much wetter and warmer
Speaker 3: early on.
Speaker 2: Yeah, Yeah, the evidence for ancient rivers and lakes is
Speaker 2: pretty strong.
Speaker 3: But then it lost its global magnetic field, its atmosphere
Speaker 3: thinned out, and most of the surface water vanished. How
Speaker 3: exactly did that happen? Atmospheric escaped the main driver.
Speaker 2: So a planet's ability to hold onto water seems directly
Speaker 2: linked to its ability to stop its atmospheric hydrogen from
Speaker 2: escaping too quickly.
Speaker 3: That seems to be a key factor. Yeah, and CGO
Speaker 3: is giving us the detailed physics for Earth we need
Speaker 3: to know. Is the escape purely thermal just atoms getting
Speaker 3: hot and fast enough, or is the solar wind actively
Speaker 3: stripping away hydrogen through electrical interactions? Is it a combination.
Speaker 2: By quantifi ying Earth's current escape rate and mechanisms the
Speaker 2: ones happening right now, we.
Speaker 3: Get a master key, a baseline for understanding that cosmic puzzle,
Speaker 3: not just here, but across the Solar System and importantly beyond, which.
Speaker 2: Leads us naturally to the biggest picture of all exoplanets.
Speaker 2: You're saying, the data CGO gathers about atmospheric escape right
Speaker 2: here on Earth will greatly inform our understanding of exoplanets
Speaker 2: planets orbiting other stars.
Speaker 3: Absolutely, this is where the physics becomes truly universal, or
Speaker 3: at least applicable far beyond home. We're discovering thousands of
Speaker 3: new exoplanets all the time now, thanks to missions like
Speaker 3: Kepler and tests.
Speaker 2: Yeah, the numbers are staggering, but.
Speaker 3: The monumental challenge isn't just finding them. It's figuring out
Speaker 3: which ones might actually be habitable, and not just habitable now,
Speaker 3: but habitable long term.
Speaker 2: And habitability isn't just about being the right distance from
Speaker 2: the star for liquid water the quote unquote habitable zone.
Speaker 2: It's also about whether the planet can actually hold onto
Speaker 2: an atmosphere.
Speaker 3: Right. That's becoming increasingly clear a planet needs to keep
Speaker 3: its atmosphere intact over billions of years. CGO helps us
Speaker 3: understand how quickly their atmospheres can escape under different conditions.
Speaker 2: Give us an example.
Speaker 3: Okay, think about planets orbiting M dwarf stars. These are
Speaker 3: the most common type of star in the galaxy, small
Speaker 3: dim red stars. To be warm enough for liquid water,
Speaker 3: a planet has to orbit incredibly close to an M dwarf,
Speaker 3: much closer than Earth orbits the Sun. But the problem
Speaker 3: is many m dwarfs are highly unstable, especially when young.
Speaker 3: They erupt with powerful flares much more frequently and intensely
Speaker 3: than our Sun sometimes.
Speaker 2: Ah So a planet orbiting super close gets blasted by
Speaker 2: these flares, constantly.
Speaker 3: Gets blasted, and that intense radiation and particle wind can
Speaker 3: aggressively strip away a planet's atmosphere over time, especially lighter
Speaker 3: gases like hydrogen.
Speaker 2: So even if a planet is in the habitable zone
Speaker 2: today based on temperature, if it's losing its atmosphere rapidly
Speaker 2: due to its stars activity.
Speaker 3: It won't be able to hold on to liquid water
Speaker 3: on its surface for the long haul, not long enough
Speaker 3: for life as we know it to potentially evolve. It
Speaker 3: might just be a dry, barren rock despite being in
Speaker 3: the right place.
Speaker 2: So CGO is effectively building the physics rule book for
Speaker 2: atmospheric survival.
Speaker 3: In a way. Yes, it's providing the robust, detailed physics
Speaker 3: models based on a planet we know does support life
Speaker 3: and has retained water. Earth scientists can then take those models,
Speaker 3: scale them for different star types, different planetary masses, different magnetic.
Speaker 2: Fields, and plug them into observations of exoplanets to better
Speaker 2: estimate their long term habitability, their water retention potential exactly.
Speaker 3: It helps us move beyond just checking the distance box
Speaker 3: to making more dynamic forecasts so about whether an atmosphere
Speaker 3: could actually stick around.
Speaker 2: So this mission cgo, it really is far more than
Speaker 2: just a survey of our immediate cosmic backyard Rushmore, it's
Speaker 2: helping define the very parameters of planetary survival potentially across
Speaker 2: the universe. It shifts the focus, adding atmospheric dynamics and
Speaker 2: retention capability as this critical filter for identifying potentially living worlds.
Speaker 3: It connects our planet's smallest, lightest component, that escaping hydrogen,
Speaker 3: to the biggest, most profound questions as ronomers are asking
Speaker 3: today about life elsewhere. It's a really elegant scientific bridge that.
Speaker 2: Brings us towards the end of this exploration into the invisible.
Speaker 2: What we've uncovered today is really fascinating. The legacy of
Speaker 2: doctor George Correthers that shocking discovery from a poll sixteen,
Speaker 2: realizing we were living inside this giant, invisible atmospheric halo.
Speaker 2: It directly drove the need for this new Correther's geocrona observatory.
Speaker 3: Absolutely and the cgomission strategically carked out at L one
Speaker 3: is set up to serve these two critical dual scientific purposes.
Speaker 3: First immediate planetary.
Speaker 2: Protection right improving space weather forecast for Artemis astronauts, for
Speaker 2: our satellites, maybe even for ground systems.
Speaker 3: And second, deep cosmic discovery mapping hydrogen escape to finally
Speaker 3: understand water retention here on Earth and using that knowledge
Speaker 3: to assess the long term habitability of planets far beyond
Speaker 3: our Solar system. It's really covering millions of miles of
Speaker 3: critical scientific territory.
Speaker 2: It is truly amazing to think that our atmosphere effectively
Speaker 2: stretches out four times farther than the Moon, and that
Speaker 2: we had to go a million miles away just to
Speaker 2: get a good look back at the sheer scope of
Speaker 2: our own home.
Speaker 3: It really reframes your perspective, doesn't it. And maybe this
Speaker 3: raises an important final thought for you, the listener, to
Speaker 3: consider as we wrap up. The cgomission is teaching us
Speaker 3: that Earth's influence stretches way way out there, a million
Speaker 3: miles into space, far beyond where we traditionally thought the
Speaker 3: edge of our atmosphere was. So what other atmosphere processes,
Speaker 3: maybe things happening in layers closer to the ground, say
Speaker 3: the ionosphere or even the mesosphere, layers that are absolutely
Speaker 3: critical for things like radio communication and GPS navigation. What
Speaker 3: other processes in those regions might we be currently underestimating
Speaker 3: or only partially understanding, simply because we haven't yet built
Speaker 3: the right dedicated tools to observe them continuously with this
Speaker 3: kind of focus.
Speaker 2: Hmm, that's a great point. Are there other invisible halos
Speaker 2: or dynamics closer in that we just haven't seen properly yet?
Speaker 3: It makes you wonder, doesn't it. It seems the deeper
Speaker 3: we look and the more specialized our tools become, the
Speaker 3: more complex, interconnected, and frankly vast our home planet reveals
Speaker 3: itself to be.