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: Hello it is It's really fantastic to have you back
Speaker 2: with us for this discussion. I was actually I was
Speaker 2: staring at my bookshelf this morning. Well, I say bookshelf,
Speaker 2: I've seen it's more of a right, it's a chaotic
Speaker 2: pile of paper and half read journals. But I was
Speaker 2: looking at this mess and just thinking about rules. As
Speaker 2: a species, we are just so obsessed with them.
Speaker 3: Oh. Absolutely, we crave patterns.
Speaker 2: We really do. We want to know that a leads
Speaker 2: to be and that the socks go on the top
Speaker 2: drawer and the heavy winter coats go in the closet.
Speaker 2: We need that order.
Speaker 3: Well, it's a survival mechanism, really, I mean, if our
Speaker 3: ancestors couldn't wreckgize the pattern of say, rustling grass usually equals.
Speaker 2: Predator right, run away exactly.
Speaker 3: We wouldn't be sitting here recording this analysis right now
Speaker 3: if they hadn't found order in the noise. We are
Speaker 3: completely hardwired for it.
Speaker 2: But the funny thing is we don't just apply that
Speaker 2: to the savannah or our closets. We project that exact
Speaker 2: same desire for order onto the cosmos itself.
Speaker 3: We want the universe to be tidy.
Speaker 2: Yes, For the longest time, we looked up at the
Speaker 2: night sky and just assumed there was this cosmic building code,
Speaker 2: like a set of architectural blueprints that every single star
Speaker 2: system had to follow and to be fair.
Speaker 3: For a while, looking at our own neighborhood, it seemed
Speaker 3: like a pretty rock solid argument because.
Speaker 2: The Solar system is surprisingly neat.
Speaker 3: It really is. It's easy to assume your own backyard
Speaker 3: is the standard for the entire neighborhood. And if you
Speaker 3: look at the solar system, it's astonishingly tidy. It's almost clockwork.
Speaker 2: You have a very specific layout. So let's actually dismantle
Speaker 2: that Solar system standard before we completely blow it up
Speaker 2: later in the show.
Speaker 3: Good idea.
Speaker 2: When you look at the Sun and it's eight planets
Speaker 2: and sorry, Pluto, we're still not counting you today. But
Speaker 2: you see two very distinct neighborhoods.
Speaker 3: Right, It's essentially a tail of two zones. In the
Speaker 3: inner zone huddle really close to the Sun, you have
Speaker 3: the terrestrial planets.
Speaker 2: Mercury, Venus, Earth, Mars exactly.
Speaker 3: These are the rocks. They're relatively small, they're dense, they're
Speaker 3: rich in iron and silicates. They're solid worlds.
Speaker 2: I always think of them as the heavy metal band
Speaker 2: of the Solar System.
Speaker 3: That's actually not a bad way to look at it.
Speaker 3: But then you cross a boundary. In astronomy, we call
Speaker 3: this the frost line or the snow line.
Speaker 2: And this is a super crucial concept for what we're
Speaker 2: talking about today.
Speaker 3: It is this line is the specific distance from the
Speaker 3: star where the temperature drops enough for volatile compounds to.
Speaker 2: Freeze things like water, ammonia, methane.
Speaker 3: Yes, they can dense into solid ice grains. Inside that line,
Speaker 3: it's too hot vapor. But outside that line, water is
Speaker 3: essentially a solid rock.
Speaker 2: Ice behaves like rock out there, exactly, And.
Speaker 3: That boundary marks the beginning of the outer zone. This
Speaker 3: is the realm of the gas giants and the ice giants.
Speaker 2: Jupiter, Saturn, Urinus, Neptune right.
Speaker 3: And his worlds are just massive. They dominate the outer
Speaker 3: system with thick, swirling atmospheres that are thousands of miles deep.
Speaker 2: So the cosmic building code that we wrote based on
Speaker 2: this observation was pretty simple. Rocks on the inside, gas
Speaker 2: giants on the outside.
Speaker 3: That was the rule.
Speaker 2: And this wasn't just an aesthetic choice by early astronomers, right, Oh,
Speaker 2: there is hard physics backing this up.
Speaker 3: Oh, there's very solid physics behind it. It all comes
Speaker 3: down to the behavior of the protoplanetary disk.
Speaker 2: The swirling saucer of gas and dust that surrounds a baby.
Speaker 3: Star right when a system is forming. The area close
Speaker 3: to the star is an absolute inferno. The intense radiation
Speaker 3: and the heat they prevent those really light gases like
Speaker 3: hydrogen and helium from sticking around.
Speaker 2: They just get blasted away.
Speaker 3: Exactlyactly, blown away by stellar winds. And more importantly, the
Speaker 3: seeds of the planets in that inner zone are made
Speaker 3: only of rock and metal, which are actually pretty rare
Speaker 3: materials in the grand scheme of the universe.
Speaker 2: So you have a scarcity of building materials close to
Speaker 2: the star.
Speaker 3: You do you can only build a small planet because
Speaker 3: there just isn't enough rock to build a big one,
Speaker 3: and because it's so hot, even if you did grab
Speaker 3: some gas, you can't hold onto a thick atmosphere.
Speaker 2: It just boils off.
Speaker 3: It gets stripped away. It's like trying to hold a
Speaker 3: snowball in a sauna. It's just not going to last.
Speaker 2: Whereas if we travel past the frost line.
Speaker 3: It is a totally different story out there. It's freezing.
Speaker 3: Ices are solid, so suddenly there is a massive abundance
Speaker 3: of building material because ice is incredibly common.
Speaker 2: So you can build a much bigger core.
Speaker 3: Exactly, you can build a solid core that is ten,
Speaker 3: maybe fifteen times the mass of Earth. And once a
Speaker 3: planetary core gets that heavy, it's gravity becomes so strong
Speaker 3: that it starts sucking up all the gas in the neighborhood.
Speaker 2: It's a tipping point, right, It.
Speaker 3: Becomes a runaway process, vacuums up the hydrogen and helium,
Speaker 3: and boom, you get a Jupiter.
Speaker 2: So the logic is completely sound. Heat creates rocks, cold
Speaker 2: creates giants. We had the observation, we had the physics,
Speaker 2: and we basically wrote the law, and.
Speaker 3: For decades pretty much all planetary formation models were built
Speaker 3: entirely around this architecture. We just assumed that if we
Speaker 3: looked at other stars we would see the exact same.
Speaker 2: Thing, which perfectly brings us to our topic today. Because
Speaker 2: of the universe, as it turns out, really enjoys mocking
Speaker 2: our laws.
Speaker 3: It does have a habit of doing that.
Speaker 2: Just when we thought we had the blueprint figured out,
Speaker 2: we found a system that is essentially looking at our
Speaker 2: physics textbooks and laughing.
Speaker 3: It's definitely curveable, a massive one.
Speaker 2: So today we are exploring a distant planetary system that
Speaker 2: is breaking all the rules, a system that is making
Speaker 2: astronomers question the very timeline of how worlds are actually born.
Speaker 3: And the system we're talking about is known as LAHS nineteen.
Speaker 2: Oh three LHS nineteen oh three.
Speaker 3: Right, And I really want to be clear about the
Speaker 3: stakes here for everyone listening. This isn't just about finding
Speaker 3: a weird planet.
Speaker 2: Right, because we find great planets all the time.
Speaker 3: We do diamond planets, lava worlds. But this is about
Speaker 3: finding a planet that, according to our standard models of
Speaker 3: accretion and migration, physically shouldn't exist where it does.
Speaker 2: It's an impossible object based on the rules we just
Speaker 2: laid out.
Speaker 3: It is an absolute enigma, and solving it requires us
Speaker 3: to completely abandon the idea that planetary systems are these
Speaker 3: static structures. We have to start treating them as dynamic,
Speaker 3: evolving timelines.
Speaker 2: I love that distinction. Space isn't just a place, it's
Speaker 2: a sequence of events. So here is the roadmap for
Speaker 2: our discussion today. We're going to transport ourselves to LHS
Speaker 2: nineteen oh three, just to set the scene. Then we
Speaker 2: are going to look at the impossible planet that was
Speaker 2: discovered by this massive international.
Speaker 3: Team, the twist in the story right, And.
Speaker 2: Then we're going to spend some serious time on the
Speaker 2: detective work because the researchers tried really, really hard to
Speaker 2: prove this planet was just a mistake in the data.
Speaker 3: They did everything they could to kill their own anomaly.
Speaker 2: And finally we will unpack the radical new theory of
Speaker 2: inside out formation that they propose to explain it.
Speaker 3: It is a classic scientific mystery.
Speaker 2: Let's start with the setting. Take us to LHS nineteen
Speaker 2: oh three. If I am looking out the window of
Speaker 2: my spaceship, what kind of star am I looking at?
Speaker 3: You are looking at a red dwarf star. Now, we
Speaker 3: often hear red dwarfs and think small dim, maybe a bit.
Speaker 2: Boring, just a little glowing ember.
Speaker 3: Right, But these are actually the most common stars in
Speaker 3: the entire galaxy. They're called m dwarfs. LHS nineteen oh
Speaker 3: three is smaller than our Sun, it's cooler than our Sun,
Speaker 3: and it is much much redder.
Speaker 2: So if it's cooler than the Goldilock zone.
Speaker 3: The habitable zone where water can be liquid.
Speaker 2: Yes, that zone would be much closer in than it
Speaker 2: is around our Sun, much closer.
Speaker 3: The entire scale of the system is sort of shrunken down.
Speaker 3: The planets are huddled closer to the fire, so to speak.
Speaker 3: But M dwarfs are also tricky. They can be very active,
Speaker 3: flaring violently, and that complicates the whole atmosphere tripping mechanic
Speaker 3: we talked about earlier, because.
Speaker 2: If it's it's growing out massive flares, it's going to
Speaker 2: blast away atmospheres even more aggressively.
Speaker 3: Exactly. Now, this system has been under surveillance for a while.
Speaker 3: This isn't a brand new star we just noticed, right.
Speaker 2: The team observing it has been at it for a bit.
Speaker 2: It's co led by researchers from McMaster University and the
Speaker 2: University of Warwick.
Speaker 3: Yes, and they've been doing incredible work using a combination
Speaker 3: of ground based telescopes and space based data to really
Speaker 3: understand the architecture of this specific system.
Speaker 2: And initially this system looked like it was following the rules.
Speaker 2: It was a good, law abiding star system.
Speaker 3: It really seemed to be. Before this recent discovery, we
Speaker 3: knew of three planets orbiting LHS nineteen oh three. Let's
Speaker 3: call them the original trio. Okay, the original trio, and
Speaker 3: their layout was incredibly comforting to astronomers because it perfectly
Speaker 3: matched the pattern we expected.
Speaker 2: Walk us through that inventory. What did the map look
Speaker 2: like originally?
Speaker 3: Well, closest to the star, you have the inner planet,
Speaker 3: and as expected, it is a rocky world. It's bathed
Speaker 3: in radiation and it's incredibly hot. It has a high density.
Speaker 3: It fits that inner zone profile perfectly.
Speaker 2: Check just like Mercury or Earth. Yeah, a rock near
Speaker 2: the star exactly.
Speaker 3: Then you move a little further out you find planet
Speaker 3: two and planet three, and these are not rocks. The
Speaker 3: team characterize them as miniature neptunes.
Speaker 2: Let's define that really quick. When we say mini neptune,
Speaker 2: we aren't talking about a water world.
Speaker 3: Are we not necessarily water? No, we are talking about
Speaker 3: planets that have a solid core, likely rock and ice,
Speaker 3: but they are enveloped in a very thick hydrogen and helium.
Speaker 2: Envelope, so they are gas dominated very much.
Speaker 3: So they have low densities. You couldn't land a spaceship
Speaker 3: on them. You would just sink through the cloud layers
Speaker 3: until the atmospheric pressure crushed you.
Speaker 2: Okay, so look at the map so far. Inner zone
Speaker 2: is a rock. Middle zone is gas. That sounds extremely familiar.
Speaker 3: It is the standard blueprint. You move away from the star,
Speaker 3: the temperature drops and the planets get gas.
Speaker 1: Here.
Speaker 3: If the survey had just stopped right there, LHS nineteen
Speaker 3: oh three would have been just another data point confirming
Speaker 3: the standard model.
Speaker 2: It would just be in a textbook as example a
Speaker 2: of normal planetary formation.
Speaker 3: It really would nothing to see here, folks. The physics works.
Speaker 2: But science is rarely that kind to us. The team
Speaker 2: didn't stop looking.
Speaker 3: They did not, and this is where the instrumentation really
Speaker 3: becomes the hero of the story. They utilize the European
Speaker 3: Space Agencies CHIOPS satellite.
Speaker 2: I really want to pause on CHIOPS because it's not
Speaker 2: as famous as Hubble or the James Webb Space Telescope,
Speaker 2: but for this specific kind of detective work. It is
Speaker 2: an absolute beast.
Speaker 3: It is a total marvel of engineering. CHOPS stands for
Speaker 3: characterizing exoplanet satellite. And note the word characterizing, right.
Speaker 2: It's not a discovery tool primarily exactly.
Speaker 3: It isn't a hunter like the Kepler telescope was, you know,
Speaker 3: scanning thousands of stars just looking for random blips. Cheops
Speaker 3: is a sniper. It stares at stars we already know
Speaker 3: have planets.
Speaker 2: Why dedicate a whole satellite to stare at something we've
Speaker 2: already found.
Speaker 3: Precision, it's all about precision. Uses ultra high precision transit photometry.
Speaker 2: Meaning it watches the shadow.
Speaker 3: Right, It measures the tiny dip in light as a
Speaker 3: planet crosses the face of the star. But it does
Speaker 3: this with such extreme sensitivity that it can determine the
Speaker 3: exact radius of a planet to a refined degree that
Speaker 3: ground based telescopes simply cannot match.
Speaker 2: Because ground telescopes have to look through Earth's messy atmosphere.
Speaker 3: Exactly, the atmosphere blurs the starlight. CHOPS is above all that.
Speaker 2: So it's the difference between seeing a blurry shadow passed
Speaker 2: by a frosted window versus seeing the crisp silhouette of
Speaker 2: a specific person and knowing exactly what kind of hat
Speaker 2: they're wearing.
Speaker 3: That is a very fair analogy. And this precision is
Speaker 3: vital because it allows us to calculate density properly. If
Speaker 3: you know the exact size from the transit shadow, and
Speaker 3: you know the mass from other methods, like how much
Speaker 3: the planet's gravity makes the star.
Speaker 2: Wobble the radial velocity exactly.
Speaker 3: You can bind size and mass and you get density,
Speaker 3: and density tells you if you are looking at a
Speaker 3: dense rock or a flicky cloud.
Speaker 2: So chi Ops is just staring at LHS nineteen oh three,
Speaker 2: refining the data on those three known planets, just doing
Speaker 2: its job, and then.
Speaker 3: A blip, a blip, a fourth signal in the data.
Speaker 3: After years of characterization efforts, the light curve revealed a
Speaker 3: completely new fourth world. It has been designated LHS nineteen oh.
Speaker 2: Three E planet E. Okay, So, now, knowing what we
Speaker 2: know about the Standard Model and knowing that we already
Speaker 2: have rocks on the inside and gas on the outside
Speaker 2: in the system, where's this new planet located?
Speaker 3: That is the multimillion dollar question. LHS nineteen oh three
Speaker 3: is the farthest planet from the star. It orbits way
Speaker 3: outside the path of those two mini Neptunes.
Speaker 2: Okay, so we are in the deep outer zone. We
Speaker 2: are well past the frost line. We are in the freezer.
Speaker 3: Correct. We are out in the region where the protoplanetary
Speaker 3: disc should have been cool, calm, and incredibly rich in
Speaker 3: volatiles and gas.
Speaker 2: So, by every law of physics we discussed earlier, planet
Speaker 2: E should be a gas giant. Absolutely, it should be
Speaker 2: another mini Neptune, or maybe even a full Neptune. It
Speaker 2: should have scooped up all that cold gas.
Speaker 3: That is the overwhelming expectation. But when the team crunched
Speaker 3: the density numbers from the CHIOPS data, the result was
Speaker 3: completely unambiguous. LHS nineteen oh three. E is not a
Speaker 3: gas giant.
Speaker 2: Don't tell me.
Speaker 3: It is a rocky planet.
Speaker 2: That makes no sense.
Speaker 3: It makes absolutely zero sense under the core accretion model.
Speaker 2: Let's visualize this planetary sandwich. We have the star, then
Speaker 2: a rock, then gas, then more gas, and then way
Speaker 2: out in the cold another rock.
Speaker 3: Exactly. It's like walking out into the ocean, getting past
Speaker 3: the crashing breakers, swimming way out into the deep water,
Speaker 3: and suddenly you just step on dry land.
Speaker 2: Wow. Why is this physically impossible though? I mean, obviously
Speaker 2: rocks can exist anywhere, right, Asteroids are rocks out in
Speaker 2: the cold. Pluter is mostly rock and iceed. Why can't
Speaker 2: a full planet be a rock out there?
Speaker 3: It's all about mass and gravity. To be a planet
Speaker 3: of this size, and Planet E is what we call
Speaker 3: a super Earth, so it's substantial. You have to form
Speaker 3: a core that is roughly five to ten times the
Speaker 3: mass of Earth. Okay, and once a protoplanet reaches that
Speaker 3: specific mass threshold, its gravity becomes too strong. It automatically
Speaker 3: starts holding onto hydrogen and helium gas.
Speaker 2: It becomes that vacuum cleaner we talked.
Speaker 3: About yes, and out in that orbit during formation there
Speaker 3: should have been plenty of gas to vacuum up. So
Speaker 3: if it formed there and it got big enough to
Speaker 3: be a super Earth, it must have an atmosphere. Physics
Speaker 3: demands it, but it doesn't. It doesn't. The fact that
Speaker 3: it is naked, just a bare rock, implies that something
Speaker 3: stopped the vacuum cleaner from working, or there was simply
Speaker 3: nothing to vacuum.
Speaker 2: This is the massive friction point for astronomers. You have
Speaker 2: a huge core sitting in what should be a gas
Speaker 2: rich environment, but it has no gas. It's like finding
Speaker 2: a sponge at the bottom of a swimming pool that
Speaker 2: is completely bone dry.
Speaker 3: That is the perfect image for it, and that dry
Speaker 3: sponge forced the research team to play detective. They couldn't
Speaker 3: just publish a paper and say, well, physics.
Speaker 2: Is broken, right, They'd be laughed out of the room.
Speaker 3: They had to rule out every other conceivable explanation. First.
Speaker 3: They had to to prove this wasn't just a misinterpretation
Speaker 3: of normal events.
Speaker 2: So let's enter the CSI exoplanet phase of our discussion.
Speaker 2: When you find an anomaly like this, you have to
Speaker 2: assume you were just missing a piece of the history,
Speaker 2: and the first assumption in astronomy is usually that something
Speaker 2: violent happened.
Speaker 3: Violence is definitely a common theme in planetary history. So
Speaker 3: the first theory the team tested was the giant impact hypothesis, right.
Speaker 2: The idea that planet Ease actually was a gas giant
Speaker 2: once it followed the rules, it had a thick atmosphere,
Speaker 2: and then wham exactly.
Speaker 3: The theory posits that the planet formed correctly as a
Speaker 3: meaning neptune, but then a massive object, perhaps a rogue
Speaker 3: planetary embryo or a huge asteroid struck it with unbelievable energy.
Speaker 2: Enough energy to just blast the atmosphere away.
Speaker 3: Into space right leaving only the dense rocky core behind.
Speaker 2: Now this sounds highly plausible to me. We know impacts
Speaker 2: happen all the time. Our own moon, formed from a
Speaker 2: Mars sized object hitting Earth. Uranus is tipped completely on
Speaker 2: its side, probably because of a massive impact. Why couldn't
Speaker 2: that be the answer here?
Speaker 3: It comes down to the energy budget. Stripping an entire
Speaker 3: planetary atmosphere, especially one held by the gravity of a
Speaker 3: super Earth, requires a cataclysmic amount of energy.
Speaker 2: It's not just a little fender bender.
Speaker 3: No, we aren't talking about a dinosaur killer asteroid. We
Speaker 3: are talking about a direct collision with another planet sized
Speaker 3: object traveling at immense.
Speaker 2: Speed, a planetary demolition derby.
Speaker 3: Yes, and when you run the numerical simulations of that
Speaker 3: kind of collision, you immediately run into major problems. First,
Speaker 3: it's just the probability.
Speaker 2: It's too rare.
Speaker 3: A collision that is precise enough to cleanly strip the
Speaker 3: gas away but somehow leave the rocky core completely intact
Speaker 3: in a stable orbit is vanishingly rare. Usually, you shatter
Speaker 3: the planet entirely.
Speaker 2: Okay, what's the second problem, where is the debris?
Speaker 3: A collision of that magnitude creates a massive debris disk,
Speaker 3: millions of fragments, dust, shattered crust, and all that dust
Speaker 3: would absorb star light and glow brightly in the infrared spectrum.
Speaker 2: Oh and we don't see any glowing dust.
Speaker 3: The system is completely clean. Furthermore, the current orbit of
Speaker 3: planet E is relatively circular and stable. A massive atmosphere
Speaker 3: destroying impact usually perturbs the orbit significantly. It makes it
Speaker 3: highly elliptical or wildly inclined compared to the other planets.
Speaker 2: So the forensic evidence just isn't there.
Speaker 3: It's not the blood spatter pattern to keep the CSI
Speaker 3: analogy going just didn't match a murder scene.
Speaker 2: Okay, so suspect number one, the giant impact, is released
Speaker 2: for lack of evidence. What about suspect number two? Because
Speaker 2: this one honestly seems the most likely to me.
Speaker 3: Migration, ah, planetary migration. This is really the darling of
Speaker 3: modern exoplanet science. We know for a fact that planets move.
Speaker 3: We are fairly certain Jupiter migrated in our own Solar
Speaker 3: system early on.
Speaker 2: Right, So the theory here simple planet e wasn't born
Speaker 2: in the outer zone. It was born in the inner zone,
Speaker 2: the rock factory, right where it belongs, and then through
Speaker 2: gravitational pinball, it got kicked out the suburbs.
Speaker 3: It's the drifting rock hypothesis. It formed inside the frost
Speaker 3: line as a normal rocky planet and then migrated outward
Speaker 3: over millions of years. This would explain perfectly why it
Speaker 3: is rocky. It was baked in the oven and then
Speaker 3: simply move to the freezer.
Speaker 2: So why did the team rule this out? It sounds
Speaker 2: like the perfect alibi.
Speaker 3: It fails the gravitational fingerprint test. You see, when planets migrate,
Speaker 3: they do not slide silently through the night. They interact
Speaker 3: gravitationally with absolutely everything they pass.
Speaker 2: Because they are heavy, they drag things around exactly.
Speaker 3: They warp space. Specifically, in a compact system like LHS
Speaker 3: nineteen oh three, where you already have three other plants
Speaker 3: tightly packed together, a migration of that magnitude would force
Speaker 3: the planets into what we call mean motion resonances.
Speaker 2: Let's break that down for the listener. What does a
Speaker 2: resonance look like.
Speaker 3: It means their orbital periods would lock into mathematical integer
Speaker 3: ratios for every two times the outer planet orbits the star,
Speaker 3: the inner one orbits exactly three times eat to two
Speaker 3: resonance or a two to one resonance.
Speaker 2: Like gears and a clock.
Speaker 3: Exactly like gears, or like pushing a kid on a swing,
Speaker 3: you time the pushes perfectly, so the energy builds up
Speaker 3: in a rhythm. We see this all over the place.
Speaker 3: The moons of Jupiter are in resonance. The planets in
Speaker 3: the trappist One system are in a beautiful resonant chain.
Speaker 3: It is the absolute hallmark of migration.
Speaker 2: It's the scar tissue left behind by planets moving through
Speaker 2: the system.
Speaker 3: Precisely, But when the researchers perform the deep orbital analysis
Speaker 3: on LHS nineteen oh three, they found that the planets
Speaker 3: are not in these resonant chains.
Speaker 2: They aren't locked together, not at all.
Speaker 3: Their orbits are essentially random relative to each other. There's
Speaker 3: no mathematical harmony there.
Speaker 2: So the total lack of resonance essentially proves they didn't
Speaker 2: push each other around.
Speaker 3: It strongly, strongly implies that the current architecture we see
Speaker 3: is the birth architecture. These planets formed roughly exactly where
Speaker 3: they are sitting right now. They didn't shuffle the deck
Speaker 3: later on.
Speaker 2: This is incredibly frustrating. It didn't get hit by anything,
Speaker 2: It didn't move from the inner.
Speaker 3: Zone, which leaves us with the impossible truth. It formed
Speaker 3: in situ, a naked, rocky world formed directly in the
Speaker 3: gas zone.
Speaker 2: We are right back to the dry sponge in the
Speaker 2: swimming pool. How do you possibly explain that without breaking physics?
Speaker 3: This brings us to the new theory proposed by the researchers,
Speaker 3: and honestly, it is a beautiful piece of lateral thinking.
Speaker 3: They realized that for decades we were looking at the
Speaker 3: problem spatially. We were obsessed with where the planets.
Speaker 2: Were right inner zone versus outer zone.
Speaker 3: But to solve this we needed to look at it temporarily.
Speaker 2: It's not about space, it's about time.
Speaker 3: Correct. The theory is called inside out planet formation or
Speaker 3: sequential formation.
Speaker 2: Okay, explain the mechanism here. How does adding time to
Speaker 2: the equations solve the gas problem?
Speaker 3: Well, we have to abandon the core assumption that all
Speaker 3: planets in a given system start growing at the exact
Speaker 3: same moment. The standard model basically assumes a concurrent formation.
Speaker 3: It's a race where the starting gun fires, and every
Speaker 3: seed everywhere starts building it once.
Speaker 2: Like putting a giant tray of cookies into the oven,
Speaker 2: all at the same time. They all bake together, right.
Speaker 3: Instead, the inside out model asks us to imagine a
Speaker 3: buffet line. The food on this buffet is the gas
Speaker 3: and dust at the protoplanetary disc. Okay, I like this,
Speaker 3: but this buffet has a very strict time limit. The
Speaker 3: kitchen is actively closing.
Speaker 2: Because the star is the kitchen manager and it wants
Speaker 2: everyone out exactly.
Speaker 3: The central star is actively blowing the gas away with
Speaker 3: its solar wind and photo evaporation. The disc is slowly
Speaker 3: dying from the moment it forms. Now in this sequential model,
Speaker 3: the inner planet forms first, it grabs the rock available
Speaker 3: in the hot zone right next to the star.
Speaker 2: Okay, so planet one is done it.
Speaker 3: Eight first, Then a bit later the process ripples outward
Speaker 3: and triggers the formation of the next zone. The mini
Speaker 3: neptune start forming, and at this point in time, the
Speaker 3: buffet is still well stocked. There's plenty of gas swhirling around.
Speaker 2: So they grow their solid cores and they successfully turn
Speaker 2: on their vas vcuums and suck up that thick hydrogen envelope.
Speaker 3: They get their fill completely, they become gas ridge mini Neptunes.
Speaker 2: But the clock is still ticking.
Speaker 3: The clock is ticking constantly, the disc is dissipating. By
Speaker 3: the time the wave of planetary formation finally reaches the
Speaker 3: outer edge where a planet E is trying to be borne,
Speaker 3: millions of years.
Speaker 2: Have passed and the buffet is empty.
Speaker 3: The trays are completely stripped clean. The gas is largely gone.
Speaker 3: It was either eaten by the mini Neptunes or it
Speaker 3: was just blown out into deep space by the star.
Speaker 2: So planet E starts to form. It manages to build
Speaker 2: a massive rocky core using the solid ice and dust
Speaker 2: pebbles that are still drifting around.
Speaker 3: It builds a core easily big enough to hold an atmosphere.
Speaker 2: But when it flips the switch and turns on its
Speaker 2: vacuum cleaner.
Speaker 3: Nothing happens. Wow, there's literally no gas left to a crete.
Speaker 3: It becomes a failed giant. It is a massive rocky
Speaker 3: core that absolutely would have been a Neptune if it
Speaker 3: had just shown up to the party a million years earlier.
Speaker 2: That is just fascinating. It's a rocky planet, not because
Speaker 2: of where it is in the cists, but because of
Speaker 2: when it is in.
Speaker 3: The timeline exactly. It is essentially a fossil of the
Speaker 3: exact moment the protoplanetary disc died. Its composition perfectly captures
Speaker 3: the moment the system ran out of fuel.
Speaker 2: This concept of sequential timing really changes how we have
Speaker 2: to view the ingredients of a world. It means you
Speaker 2: can't just look at an orbit through a telescope and
Speaker 2: instantly know what the planet is made of based on
Speaker 2: a simple chart.
Speaker 3: You can't. You have to know the history. You have
Speaker 3: to know the temporal flow of the system. The researcher
Speaker 3: suggests that the final composition of a planet is actually
Speaker 3: a record of the local conditions at the exact time
Speaker 3: of its final assembly.
Speaker 2: Local conditions at the time of final assembly. That honestly
Speaker 2: sounds like a manufacturing disclaimer on the back of a TV.
Speaker 3: It effectively is. It tells us that planet formation is
Speaker 3: a chaotic, highly time dependent process. It is not a
Speaker 3: static blueprint printed out at the beginning of time. It
Speaker 3: is a movie, and the ending of that movie depends
Speaker 3: entirely on how fast the early scenes play out.
Speaker 2: So LHS nineteen oh three E is a naked rock
Speaker 2: simply because it was late It was the ultimate straggler.
Speaker 3: He was the late bloomer in a dying system. It
Speaker 3: missed the gas window.
Speaker 2: This realization must be sending massive ripples through the astronomical community,
Speaker 2: because if this inside out sequential process can happen at
Speaker 2: LHS nineteen oh three, surely it is happening elsewhere.
Speaker 3: That is the big sweeping implication of this paper. We
Speaker 3: have to ask ourselves a very uncomfortable question. Is this
Speaker 3: system a unicorn, just a bizarre freak occurrence, or is
Speaker 3: it actually a very common pattern that we simply haven't
Speaker 3: had the technology to see until right now.
Speaker 2: I suspect from your tone you lean toward the latter.
Speaker 3: I absolutely do. The data point argument is very strong here.
Speaker 3: You see, for years our detection methods were inherently biased.
Speaker 3: We found hot jupiters because they are huge and the
Speaker 3: orbit closely making massive transits in huge gravitational wobbles.
Speaker 2: We found what was loud and easy to find exactly.
Speaker 3: We built our standard models based on the loudest things
Speaker 3: in the sky and our own backyard. Now that we
Speaker 3: have ultra precise tools like chiops, and soon we'll have
Speaker 3: the Roman Space Telescope, we are finally seeing the subtle
Speaker 3: quiet systems.
Speaker 2: We are seeing the true diversity of the galaxy.
Speaker 3: We are realizing that the Solar System standard might just
Speaker 3: be one specific item on a very, very long menu.
Speaker 3: You can have systems with hot jupiters, you can have
Speaker 3: systems with migrating neptunes crashing through the inner system.
Speaker 2: And you can have inside out systems where the outer
Speaker 2: worlds are starved rocks.
Speaker 3: It's all about timing and local conditions. The galaxy is
Speaker 3: far more creative than our old models gave it credit for.
Speaker 3: The lead researchers basically echoed this sentiment, pointing out how
Speaker 3: remarkable it is to witness a rocky world confidently existing
Speaker 3: right where theory says it absolutely shouldn't be.
Speaker 2: It reminds me a bit of the Fermi paradox in
Speaker 2: a weird way. We keep asking, where is everyone assuming
Speaker 2: that life absolutely needs an earth like system with an
Speaker 2: Earth like timeline to exist. But if planetary systems are
Speaker 2: this wildly diverse, maybe the conditions for life are also
Speaker 2: more diverse, or perhaps much rarer than we thought.
Speaker 3: It certainly complicates things. If you need a very specific
Speaker 3: architecture to protect a habital planet like maybe you need
Speaker 3: a Jupiter sitting further out to catch all the incoming
Speaker 3: asteroids and shield the inner planets.
Speaker 2: Right the Jupiter shield theory, Yes, and.
Speaker 3: If that specific architecture is rare, then maybe calm earths
Speaker 3: are rare. But on the flip side, maybe rocky worlds
Speaker 3: are far more common in the safe, quiet outer zones
Speaker 3: than we ever dared to hope.
Speaker 2: That's a really hopeful thought. Think about a rocky super
Speaker 2: Earth way out in the outer zone. If it had
Speaker 2: enough internal heat from radioactive decay or tidal forces, could
Speaker 2: it have a subsurface ocean.
Speaker 3: It's completely possible. Look at Enceladus and Europa right here
Speaker 3: in our own system. They are icy moons with deep,
Speaker 3: vast liquid water oceans under the ice. A massive super
Speaker 3: Earth in that position could potentially harbor incredibly deep liquid
Speaker 3: water protected from the vacuum by a thick crust of ice.
Speaker 2: Opens up a totally new class of potential real estate
Speaker 2: for astrobiologists to think about.
Speaker 3: It really forces us to stop being carbon chauvinists or
Speaker 3: I guess, solar system chauvinists about how planets are supposed
Speaker 3: to look. We are not the gold standard. We are
Speaker 3: just one random outcome of a chaotic, time sensitive process.
Speaker 2: So, looking forward, we have this brilliant new theory of
Speaker 2: sequential formation. How do we prove it? What is the
Speaker 2: next logical step for this research team to confirm this
Speaker 2: wasn't just a lucky guess.
Speaker 3: The immediate next step is atmosphere characterization, and the tool
Speaker 3: for that is the James Web.
Speaker 2: Space Telescope uh JWST. What exactly would web be looking
Speaker 2: for in a system like this. It can't look at
Speaker 2: the rock because there's no atmosphere to sniff, correct.
Speaker 3: But it can look at the many neptunes in the middle.
Speaker 3: If the inside out sequential theory is right, the chemical
Speaker 3: abundance ratios in their atmospheres should tell a story. Specifically,
Speaker 3: we look at the amount of carbon versus the amount
Speaker 3: of oxygen.
Speaker 2: Why those two elements.
Speaker 3: Because as a protoplanetary disk evaporates over time, the ratio
Speaker 3: of gas to solid dust changes. Carbon and oxygen freeze
Speaker 3: at different temperatures in different times, so the ratio of
Speaker 3: those elements floating in the gas changes as the disc
Speaker 3: gets older.
Speaker 2: Oh I see, So the chemical signature basically acts like
Speaker 2: a timestamp.
Speaker 3: Exactly the chemistry gets baked into the atmosphere of the
Speaker 3: planet when it forms. If web can analyze the light
Speaker 3: passing through the air of those two mini Neptunes and
Speaker 3: find a specific gradient in those ratios that it implies
Speaker 3: they formed at different times.
Speaker 2: That would be the smoking gun.
Speaker 3: It would be definitive proof for sequential formation. We would
Speaker 3: literally be reading the timeline of a dead disc in
Speaker 3: the clouds of a living planet.
Speaker 2: That is just incredible. We are using telescopes to do
Speaker 2: temporal archaeology on a solar system one hundred light years away.
Speaker 3: It really is the golden age of exoplanetary science. We
Speaker 3: are finally moving from stamp collecting where we just find
Speaker 3: planets and put them on a list, to actually understanding
Speaker 3: their life stories.
Speaker 2: Well, this analysis has certainly blown my mind today. We
Speaker 2: started with such a simple, comforting rule rocks inside.
Speaker 3: Gas outside, a very tidy rule, and.
Speaker 2: We ended up with a starved, naked super Earth sitting
Speaker 2: out in the freezing dark, telling us a story about
Speaker 2: the agonizing death of its birth cloud.
Speaker 3: And reminding us once again that the universe is far
Speaker 3: more dynamic and messy than our textbooks would like to admit.
Speaker 2: I think the biggest takeaway for me is just the
Speaker 2: element of time. We look up at the night sky
Speaker 2: and it looks so perfectly still and eternal, But it's
Speaker 2: really all just a freeze frame of a violent, constantly
Speaker 2: shifting history.
Speaker 3: Chaos in order, just dancing together across millions of years.
Speaker 3: That is the true nature of the cosmos.
Speaker 2: Thank you so much for breaking all this down. It
Speaker 2: really makes you wonder if our tidy little system is
Speaker 2: actually the weird one. What does normal actually look like
Speaker 2: out there, What other bizarre rule breaking architectures are hiding
Speaker 2: in the dark, just waiting for a satellite to spot them.
Speaker 3: And importantly, how many anomalies have we simply missed or
Speaker 3: ignored in the past because we were only looking for
Speaker 3: patterns that matched our own home.
Speaker 2: That is a fascinating thought to end on. Keep looking up,
Speaker 2: keep questioning the rules you think are permanent, and we
Speaker 2: will see you in the next discussion. Goodbye, Sai.