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: I want you to close your eyes for a second,
Speaker 2: just for a moment. Forget about your to do list,
Speaker 2: forget about the emails pinging in your inbox. Instead, I
Speaker 2: want you to picture a heist.
Speaker 3: Not your typical heist though, No ski masks, no getaway cars, no,
Speaker 3: nothing like that.
Speaker 2: This is a heist happening, oh about two hundred million
Speaker 2: miles away from where you're sitting. Picture a robot, maybe
Speaker 2: the size of a large van, and it's just floating
Speaker 2: in the complete absolute silence of deep space.
Speaker 3: And its target is this mountain of rubble that's just
Speaker 3: tumbling through the dark.
Speaker 2: Exactly it's trying to I don't know, high five. This
Speaker 2: spinning pile of rocks and mountain.
Speaker 3: Of rubble is actually, you know, not far from the
Speaker 3: scientific term. We're talking about the asteroid Benu. It's what's
Speaker 3: called a rubble pile asteroid, which means it's basically a
Speaker 3: loose collection of rocks and dust all held together by well,
Speaker 3: not much more than its own weak gravity.
Speaker 2: It's it's fragile, right, And this Robi, which is Nanza's
Speaker 2: Osyrius for Rex spacecraft, had one job, just one incredibly delicate,
Speaker 2: high stakes job. Go to this asteroid, match its speed,
Speaker 2: match it spin, then reach out an arm, touch the
Speaker 2: surface for just a few seconds, grab a little souvenir,
Speaker 2: and then fly all the way home.
Speaker 3: It sounds so simple when you put it like that.
Speaker 2: It sounds simple when you say it fast. But it
Speaker 2: was anything but. I mean, the level precision is just
Speaker 2: it's mind boggling.
Speaker 3: And it was even harder than they planned when they
Speaker 3: actually made contact. This was back in twenty twenty. The
Speaker 3: surface was so much softer than their models predicted.
Speaker 2: Softer.
Speaker 3: Yeah, the collection arm it almost sank right into the astray.
Speaker 3: It was like trying to punch a ball pit. The
Speaker 3: surface just gave way.
Speaker 2: I remember seeing the video from the spacecraft's camera. Yes,
Speaker 2: it was terrifying to watch. Yeah, dust and pebbles flying everywhere.
Speaker 2: You realize, if that arm gets stuck, or if the
Speaker 2: thrusters fire at the wrong second, that's it. The whole
Speaker 2: mission is lost.
Speaker 3: Billions of dollars, decades of work just gone. But they
Speaker 3: pulled it off. They fired the thrusters, they backed away,
Speaker 3: and they had the goods. They sealed up the sample capsule.
Speaker 2: And then came the long trip home and finally, in
Speaker 2: twenty twenty three, that little capsule came blazing through our
Speaker 2: atmosphere and parachuted down into the Utah Desert.
Speaker 3: And that's another moment where you're holding your breath. I mean,
Speaker 3: if that parachute doesn't deploy correctly, if the capsule cracks
Speaker 3: open on impact.
Speaker 2: All that effort, all that distance, and you just end
Speaker 2: up with a very expensive crater in the sand exactly.
Speaker 2: But it worked. It stuck the landing, and inside, once
Speaker 2: they got it into a pristine, sterile clean room and
Speaker 2: carefully opened it up, they found dust, just a little
Speaker 2: cups worth of this very dark, very jagged dust.
Speaker 3: And that dust, specifically about a teaspoon of it is
Speaker 3: what we are here to talk about today, because this
Speaker 3: isn't just a story about an amazing engineering feat. Yeah,
Speaker 3: we were looking at a paper that was published literally yesterday,
Speaker 3: February ninth, twenty twenty six, in the Proceedings of the
Speaker 3: National Academy of Sciences. And it turns out that teaspoon
Speaker 3: of Dust contains a story that well, it completely rewrites
Speaker 3: what we thought we knew about the chemistry of life.
Speaker 2: It really does. It's one of those moments in science
Speaker 2: where you realize the recipe book you've been using might
Speaker 2: have been missing a critical chapter, or maybe we were
Speaker 2: just reading the wrong one entirely.
Speaker 3: That's a great way to put it.
Speaker 2: So let's set the stage here. The big headline is
Speaker 2: that researchers from Penn State found amino acids in this
Speaker 2: venue dust. But and I want to be really clear
Speaker 2: on this, because it confused me at first finding amino
Speaker 2: acids in space. That's not the new part, is it.
Speaker 3: No, And you are absolutely right to flag that that's
Speaker 3: the key nuance. If the headline was just scientists find
Speaker 3: organics on asteroid, we'd say, ok, add it to the
Speaker 3: growing list.
Speaker 2: We've known for decades, really that space rocks can carry
Speaker 2: these kinds of molecules.
Speaker 3: So what's the big deal. Why is this particular discovery
Speaker 3: causing such a stir.
Speaker 2: It's because of the how. It's not that they found
Speaker 2: amino acids. It's the story those amino acids have to tell.
Speaker 2: It's about their history. It's like finding a person in
Speaker 2: New York City. That's not a story, but finding out
Speaker 2: they got there by walking from Antarctica, that's a story.
Speaker 3: Okay, I like that. So we're looking at the molecule's journey.
Speaker 3: It's origin story we are, And for the last fifty
Speaker 3: years we had a pretty solid theory about that origin story.
Speaker 3: We thought the answer was always you know, warmth and water.
Speaker 2: The famous warm little pond that Darwin talked.
Speaker 3: About, the very same, the classic idea. But the samples
Speaker 3: from Benu they're telling us something completely different. They're saying
Speaker 3: the ingredients for life don't just form in cozy, warm ponds.
Speaker 2: They formed somewhere else.
Speaker 3: They can form in the deep freeze, in the pitch dark,
Speaker 3: in an environment that should be, by all accounts, completely
Speaker 3: hostile to creating these delicate molecules.
Speaker 2: We're talking about, what a radioactive environment.
Speaker 3: We're talking about frozen eyes being blasted by gamma rays,
Speaker 3: the harsh, unforgiving vacuum of the outer Solar system.
Speaker 2: Wow, that's well, it sounds more like the origin story
Speaker 2: for comic book Supervillain, not the origin story for life
Speaker 2: on Earth.
Speaker 3: And that's precisely why this is a revelation. The lead author,
Speaker 3: Alison Bozinski says, it flips the script on where we
Speaker 3: should be looking for life's ingredients and maybe even life itself.
Speaker 2: So our mission today for this deep dive seems pretty clear.
Speaker 2: We're going to unpack this brand new study. We're going
Speaker 2: to look at the incredible technology this team, led by
Speaker 2: Alison Bozinski and Elflee Macintosh used to basically read the
Speaker 2: atomic history of these molecules, and we're going to try
Speaker 2: to understand why a freezing radioactive void might actually be
Speaker 2: a better kitchen for creating life's building blocks than a
Speaker 2: warm bath.
Speaker 3: And beyond that, we have to talk about what this
Speaker 3: means for the rest of the universe, because if you
Speaker 3: don't need a special Goldilocks planet with warm oceans to
Speaker 3: make amino acids, if you can just make them in
Speaker 3: the cold darkness of space.
Speaker 2: Then the universe might be a lot more seeded with
Speaker 2: potential than we ever thought.
Speaker 3: Exactly the ingredients for the recipe it could be everywhere.
Speaker 2: Okay, I love this let's start with the sample itself,
Speaker 2: the Messenger from the Dawn of Time? Why this rock?
Speaker 2: Why Benu? What made NASA spend over a billion dollars
Speaker 2: to go to this specific pile of rubble.
Speaker 3: To really appreciate the science, you have to appreciate the sample.
Speaker 3: And as you mentioned, this material from Osiris Rex is
Speaker 3: special for one big reason. The word is pristine.
Speaker 2: Pristine meaning untouched.
Speaker 3: Completely untouched. See, most of the time when we study
Speaker 3: space rocks, we're studying meteorites, and meteorites are well, they're compromised,
Speaker 3: they've been through the Ringer, right.
Speaker 2: They didn't have a nice, gentle parachute landing in Utah,
Speaker 2: not at all.
Speaker 3: Think about the journey of a typical meteorite. It spends
Speaker 3: maybe millions, even billions of years floating through space, getting
Speaker 3: bombarded by radiation. Then it hits Earth's atmosphere at what
Speaker 3: thirty thousand miles an hour.
Speaker 2: It's a fireball. It literally burns up.
Speaker 3: It burns at thousands of degrees, the outer layers or vaporized.
Speaker 3: It often breaks apart. It's a profoundly traumatic entry. And
Speaker 3: then if a piece survives, it lands maybe in the
Speaker 3: Antarctic ice. If we're lucky, or maybe it lands in
Speaker 3: a field in Iowa.
Speaker 2: Or jungle or the ocean.
Speaker 3: Exactly, and it just sits there. It gets rained on.
Speaker 3: Microbes and bacteria from Earth's soil start to crawl all
Speaker 3: over it. It gets buried in mud. Humans eventually find it
Speaker 3: and touch it with their oily, greasy fingers.
Speaker 2: So it's contaminated from the second it enters our world.
Speaker 2: It's being altered.
Speaker 3: It is heavily, heavily contaminated. From a chemical analysis standpoint,
Speaker 3: It's like trying to read an ancient scroll that's been
Speaker 3: dropped in a puddle, then dried by a fire, and
Speaker 3: then scribbled on by a toddler. You can still make
Speaker 3: out some of the original text, but you're never one
Speaker 3: hundred percent sure what's original and what's just dirt from
Speaker 3: the journey.
Speaker 2: But the Benu sample is different.
Speaker 3: The Benu sample is a completely different ballgame. It was
Speaker 3: a grab and go mission. We flew to the source,
Speaker 3: We used a sterile robotic arm to grab the dust.
Speaker 3: We sealed it in a hermetically sealed capsule right then
Speaker 3: and there in space, and we brought it home.
Speaker 2: It never touched Earth's atmosphere. It never saw rain. It
Speaker 2: never encountered a single Earth bacterium.
Speaker 3: Until the moment it was opened in that NASA clean room.
Speaker 3: That dust was exactly as it had been for four
Speaker 3: point six billion years, floating out there in the void.
Speaker 2: So what this study is looking at is the real deal.
Speaker 2: This is unfiltered history.
Speaker 3: It is the closest thing we have to a perfect
Speaker 3: time capsule from the birth of our solar system, back
Speaker 3: before Earth even had oceans, before the first cell ever divided.
Speaker 3: This is a snapshot of the raw material that built everything.
Speaker 2: And what's just staggering to me is the amount of
Speaker 2: material they're working with. You said a teaspoon. The breakthrough
Speaker 2: came from a sample no bigger than a teaspoon of dust.
Speaker 3: It really is a testament to the lane level of
Speaker 3: technology we have now. The team at Penn State, the
Speaker 3: lead researchers Alison Basinski and Offley Macintosh, along with Christopher House,
Speaker 3: Catherine Freeman, and Mila Mattney, they weren't just putting this
Speaker 3: dust under a normal microscope. They were using instruments that
Speaker 3: tear molecules apart adam by adam and weigh them.
Speaker 2: Zuski had a quote in the press release about this,
Speaker 2: didn't she something like without these advances in technology.
Speaker 3: She said, we would never have made this discovery. And
Speaker 3: she's absolutely right, because they were looking for what she
Speaker 3: called really low abundances. These aren't huge, visible chunks of
Speaker 3: organic stuff. These are trace amounts parts per billion locked
Speaker 3: inside the mineral structure of the dust. You need instruments
Speaker 3: with incredible sensitivity to even see them, let alone analyze
Speaker 3: their history.
Speaker 2: Okay, so let's get into what they actually found. We
Speaker 2: keep using the term amino acids, and I feel like
Speaker 2: most of us have heard that term, maybe on a
Speaker 2: nutritional labels or in a biology class. But let's really
Speaker 2: define it for our context here. What exactly are we
Speaker 2: looking at.
Speaker 3: The best analogy, and it's one we use a lot
Speaker 3: in science communication is lego bricks.
Speaker 2: Legos. I can do legos. Everyone gets legos.
Speaker 3: Imagine you have a giant bin of mixed lego bricks.
Speaker 3: An individual brick, say a single red two by four piece,
Speaker 3: is just a piece of plastic. It doesn't do much
Speaker 3: on its own, but if you start snapping them together
Speaker 3: in a specific sequence, you can build anything. A house,
Speaker 3: a spaceship, a working model of a car engine. The
Speaker 3: complexity emerges from how you connect the simple pieces.
Speaker 2: So the power isn't in the brick, it's in the
Speaker 2: structure you build with it.
Speaker 3: Precisely, in the world of biology, amino acids are those
Speaker 3: lego bricks. You snap them together in long chains to
Speaker 3: build proteins, and proteins proteins are the machines that run
Speaker 3: the city of life. They do all the work, They
Speaker 3: do everything. They form the physical structure of your cells,
Speaker 3: like the steel beams and a skyscraper. They act as
Speaker 3: enzymes to catalyze chemical reactions like digesting your food. They
Speaker 3: carry oxygen in your blood. They fight off diseases as antibodies.
Speaker 3: Without protein, you can't replicate DNA, you can't have a metabolism.
Speaker 3: There is no life as we know it without them.
Speaker 2: So finding these fundamental lego bricks on an asteroid is
Speaker 2: a huge deal because it suggests the raw materials for
Speaker 2: life weren't invented here on Earth. Yeah, we didn't have
Speaker 2: to manufacture the plastic for the bricks ourselves. They were
Speaker 2: delivered to us pre made in the box.
Speaker 3: That is a perfect way to phrase it. And in
Speaker 3: this particular study from Penn State, they were focused on
Speaker 3: one specific very important amino acid glycine.
Speaker 2: Glycine, Why that one is it special?
Speaker 3: It's special because it's the simplest. If we're sticking with
Speaker 3: the Lego analogy, glycine is the most basic brick. It's
Speaker 3: the little two by two square. It's the smallest possible
Speaker 3: amino acid, just a tiny two carbon molecule. But because
Speaker 3: it's so simple and fundamental, it's found everywhere in biology.
Speaker 2: Okay, so they found glycine in the binu dust. But
Speaker 2: as we established earlier, we found glycine in space before
Speaker 2: we have Yes, So this is where we get to
Speaker 2: the script slip. You mentioned Lit's dig into the old
Speaker 2: theory before this paper dropped yesterday. If I were to
Speaker 2: ask you, how does glycine form in space? What would
Speaker 2: the textbook answer have been?
Speaker 3: The textbook answer for about half a century would have
Speaker 3: been a process called Strucker synthesis.
Speaker 2: Treker synthesis sounds like a villain's evil plan in a
Speaker 2: spy movie. We must initiate Operation Strecker.
Speaker 3: It does have that ring to it, doesn't it. But
Speaker 3: it's actually some pretty classic old school chemistry. It's named
Speaker 3: after Adolph Strecker, who figured this out all the way
Speaker 3: back in the eighteen fifties.
Speaker 2: The eighteen fifties, So this is really foundational chemistry.
Speaker 3: Very foundational, And for Streker synthesis, you need a few
Speaker 3: key ingredients. First, you need some kind of aldehyde or ketne.
Speaker 3: You can just think of that as your basic carbon
Speaker 3: containing molecule. Then you need ammonia. That's your source of nitrogen.
Speaker 3: And you need hydrogen cyanide.
Speaker 2: Hydrogen cyanide. Wait a second, isn't that Isn't that a
Speaker 2: lethal poison to us?
Speaker 3: Absolutely, it's incredibly toxic, But in the world of prebiotic chemistry,
Speaker 3: it's an essential ingredient. It's a very simple molecule containing
Speaker 3: carbon and nitrogen, and it's very very reactive.
Speaker 2: It's just so ironic that a key ingredient for life
Speaker 2: is something that's so deadly to life.
Speaker 3: Chemistry is full of these little ironies. But here's the
Speaker 3: crucial part of the recipe. If you just take those
Speaker 3: three ingredients, the aldehyde, the ammonia, the cyanide, and you
Speaker 3: put them in a jar and shake them up as gases,
Speaker 3: basically nothing happens. They just bounce off each other. They
Speaker 3: need a catalyst, a match.
Speaker 2: Maker, if you will, and the match maker is water.
Speaker 3: Liquid water. Absolutely, water acts as a solvent. It allows
Speaker 3: these molecules to dissolve, to move around freely, to exchange protons,
Speaker 3: and to actually interact and react with each other. But
Speaker 3: you need one more thing. You need energy. You need heat. Well,
Speaker 3: the heat, because molecules are fundamentally lazy, they're stable in
Speaker 3: the current forms. To get them to break their existing
Speaker 3: bonds and form new, more complex ones, to get them
Speaker 3: to rearrange themselves into an amino acid, you need to
Speaker 3: give them an energetic shove. Heat provides that shove. It's
Speaker 3: kinetic energy. It makes the molecules vibrate and smash into
Speaker 3: each other with enough force to trigger the reaction.
Speaker 2: So the warm little pond concept isn't just a nice
Speaker 2: poetic image. It's a literal chemical requirement. You need a
Speaker 2: liquid medium for the ingredients to mix, and you need
Speaker 2: warmth to make the reaction go precisely.
Speaker 3: So, for fifty years, whenever we found amino acids and meteorites,
Speaker 3: the assumption was always Okay, this rock must have, at
Speaker 3: some point in its history been part of a larger
Speaker 3: parent body that had liquid water and some source of
Speaker 3: internal heat.
Speaker 2: We just assumed it was cooked in some kind of
Speaker 2: cosmic crock pot, maybe inside a big asteroid with hydrothermal vents,
Speaker 2: or some surface ocean warmed by radioactive decay.
Speaker 3: Exactly. We were, in a way projecting our own planet
Speaker 3: story onto the rest of the Solar System. We see
Speaker 3: life thriving in water here, so we assumed life's ingredients
Speaker 3: must also need water there.
Speaker 2: But Benu is here to tell us that's not the
Speaker 2: only way.
Speaker 3: Benu is telling us something radically different. And this is
Speaker 3: where the real detective work gets incredibly cool. This is
Speaker 3: where we have to talk about isotopes.
Speaker 2: Lisotopes. Okay, I remember the term from high school chemistry,
Speaker 2: but let's do a quick refresher. How does weighing an
Speaker 2: atom tell you anything about its past.
Speaker 3: Think of atoms of a particular element like carbon, as
Speaker 3: all being part of the same family. They all have
Speaker 3: six protons. That's what makes them carbon. But some family
Speaker 3: members might weigh a little more than others. They might
Speaker 3: have an extra neutron or two in their nucleus.
Speaker 2: So it's the same element chemically, it just has a
Speaker 2: bit more mass. It's the chubby cousin of the family.
Speaker 3: That's a perfect analogy. It's a chubby atom had a
Speaker 3: little extra baggage. It's still carbon. It behaves light carbon.
Speaker 3: It forms bonds like carbon, but it's heavier. We call
Speaker 3: these heavier versions isotopes. Carbon twelve is the common one.
Speaker 3: Carbon thirteen is the heavier one. Now Here is the
Speaker 3: magic trick of this whole science. The ratio of the
Speaker 3: heavy atoms to the light atoms in a molecule acts
Speaker 3: like a passport stamp. It tells you where that molecule
Speaker 3: was born.
Speaker 2: Wait, how why would the environment affect how many chubby
Speaker 2: atoms get included in the molecule.
Speaker 3: It comes down to a principle called the kinetic isotope effect.
Speaker 2: Okay, but that sounds complicated, but break it down for us.
Speaker 3: It's actually just about that molecular laziness we talked about again.
Speaker 3: It turns out that chemical bonds involving the heavier isotope
Speaker 3: carbon thirteen are just a tiny bit stronger and more stable.
Speaker 3: They take a little more energy to break. So if
Speaker 3: you have a chemical reaction happening in that warm pond,
Speaker 3: a reaction that requires breaking bonds, it's slightly easier. It
Speaker 3: takes less energy to break the bond with the lighter
Speaker 3: carbon twelve atom, so.
Speaker 2: Nature takes the path of least resistance. The reaction prefers
Speaker 2: the lighter easier to work with atoms. You got it.
Speaker 3: So, generally speaking, chemical reactions driven by heat and happening
Speaker 3: in water will end up with a product that is
Speaker 3: depleted in the heavy isotope. They discriminate against the heavy stuff.
Speaker 2: So if I analyze the molecule made in a warm environment,
Speaker 2: it's isotopic fingerprint should show it's full of the light stuff.
Speaker 2: Relatively speaking, yes, it.
Speaker 3: Will have a very specific, predictable ratio of light versus
Speaker 3: heavy atoms. But here's the amazing part. At extremely cold
Speaker 3: temperatures we're talking deep space cold hundreds of degrees below zero,
Speaker 3: the rules of chemistry change. When you're not using heat
Speaker 3: to drive reactions, but you're using high energy radiation instead,
Speaker 3: that discrimination goes away.
Speaker 2: Radiation doesn't care if an atom is chevy or not.
Speaker 3: Radiation is like a sledgehammer. Heat is like a gentle push.
Speaker 3: The sledgehammer doesn't care if the one bond is slightly
Speaker 3: stronger than another. It just smashes everything. So reactions that
Speaker 3: are driven by radiation and frozen ice tend to incorporate
Speaker 3: the heavy and light isotopes in a different, more random
Speaker 3: seeming ratio. They don't show the same preference for the
Speaker 3: light stuff.
Speaker 2: I think I'm getting it. So the Penn State team,
Speaker 2: kachen Ski, Macintosh and the others, they take the glycine
Speaker 2: from the Beni sample. They put it in their super
Speaker 2: sensitive machine.
Speaker 3: A set of custom instruments, a mass spectrometer.
Speaker 2: And they literally just count the number of heavy carbon
Speaker 2: atoms versus light carbon atoms than nitrogen atoms too.
Speaker 3: That's essentially it. They measure that ratio with incredible precision,
Speaker 3: and the ratio they found it sacreamed coald. It screamed ice.
Speaker 2: It didn't look like the ratio from the Streker synthesis,
Speaker 2: the warm pond dress.
Speaker 3: It wasn't even in the same ballpark. The isotopic signature
Speaker 3: was completely inconsistent with formation in liquid water, but it
Speaker 3: perfectly matched the signature you'd expect from formation in solid
Speaker 3: frozen ice. Ice frozen solid, and not just ice sitting
Speaker 3: there peacefully, but ice being actively zapped by high energy
Speaker 3: cosmic rays and gamma rays.
Speaker 2: Okay, so let me see if I can picture this.
Speaker 2: The ingredients we talked about before, the ammonia, the cyani
Speaker 2: the simple carbon molecules. They're not dissolved in water. They're
Speaker 2: just trapped frozen solid inside.
Speaker 3: A block of ice exactly. They are suspended in the
Speaker 3: ice matrix like fruit in a jello mole and.
Speaker 2: Then over millions of years, radiation from space comes along
Speaker 2: and just zaps them, and that forces them to become
Speaker 2: amino acids.
Speaker 3: That's the idea. The process is called radiolysis. The high
Speaker 3: energy radiation particle smashes into a water molecule in the ice,
Speaker 3: shattering it and creating these incredibly reactive fragments called radicals.
Speaker 3: These radicals are like like chemical grenades. They are desperate
Speaker 3: to react with anything nearby, so they attack the frozen cyanide,
Speaker 3: they attack the ammonia, and they force them to combine
Speaker 3: in new ways.
Speaker 2: So the radiation is providing the energy that the heat
Speaker 2: would have provided in the warm pond.
Speaker 3: Precisely, but it's doing it without ever melting the ice.
Speaker 3: It's a cold forging process, and it's a process that
Speaker 3: happens in what the paper calls the outer reaches of
Speaker 3: the early Solar System.
Speaker 2: The outer reaches, so we're talking way out there beyond Mars,
Speaker 2: beyond the asteroid belt, maybe upast Jupiter, way out.
Speaker 3: In the cold, dark vacuum, in a region we typically
Speaker 3: think of as a chemical wasteland, a place we considered
Speaker 3: hostile to the formation of complex organic molecules.
Speaker 2: This is that script flip that Bazinski mentioned.
Speaker 3: It is her direct quote was our results flip, the
Speaker 3: script on how we have typically thought amino acids formed.
Speaker 2: It's just it's incredible. It suggests that the potential for
Speaker 2: life is so much more rugged and persistent than we
Speaker 2: gave it credit for. It doesn't need to wait around
Speaker 2: for a perfect little planet with a nice ocean to
Speaker 2: get started. The chemistry can begin in the harshest parts
Speaker 2: of the void.
Speaker 3: That's the profound implication. It means these fundamental molecules aren't
Speaker 3: rare flukes restricted to these little goldilock zones where the
Speaker 3: temperature is just right for liquid water. Bazinski put it perfectly,
Speaker 3: It now looks like there are many conditions where these
Speaker 3: building blocks of life can form.
Speaker 2: It's all about diversity.
Speaker 3: Diversity in the pathways to life. Can you make glycine
Speaker 3: in a warm watery asteroid, Yes, absolutely, that method works,
Speaker 3: But this shows you can also make it in a
Speaker 3: radioactive ice cube floating in the dark.
Speaker 2: That just feels huge. It makes the universe feel less
Speaker 2: like this vast empty place where life is a one
Speaker 2: and a trillion miracle, and more like a giant factory
Speaker 2: that's constantly in different departments churning out the necessary parts
Speaker 2: for life, no matter the local conditions.
Speaker 3: A factory is a fantastic analogy. And this brings us
Speaker 3: to a really fascinating comparison. The study made really nailed
Speaker 3: down their case. They didn't just look at Benu by itself.
Speaker 3: They put it head to head with the undisputed celebrity
Speaker 3: of the metiorrite world.
Speaker 2: Ah. Yes, you're talking about the Murchison metiaorite, the heavyweight champion.
Speaker 3: The one and only Murchison. It fell in a shower
Speaker 3: over the town of Murchison, Australia, back in nineteen sixty nine.
Speaker 2: Nineteen sixty nine, what a year for space. We go
Speaker 2: to the Moon and a piece of the early Solar
Speaker 2: System comes to us.
Speaker 3: A huge year, and Murchison is this carbon rich meteorite
Speaker 3: that became the absolute gold standard for astrobiology for fifty years.
Speaker 3: If you were a scientist in the eighties nineties, even
Speaker 3: the two thousands, and you wanted to study amino acids
Speaker 3: from space. You begged, borrowed, and stole for a tiny
Speaker 3: crumb of Murchison.
Speaker 2: And what did Murchison's story tell us?
Speaker 3: Well, for all those decades, Murchison consistently confirmed the old theory.
Speaker 3: When scientists analyzed the isotopes of the amino acids inside Murchison,
Speaker 3: the fingerprint was clear. It said I was made in
Speaker 3: warm liquid water.
Speaker 2: So Murchison fits the classic warm pond theory to a
Speaker 2: t perfectly.
Speaker 3: The evidence from murch strongly suggests its parent body, the
Speaker 3: larger asteroid it broke off from, was a place that
Speaker 3: had liquid water flowing and relatively mild temperatures, conditions that
Speaker 3: ironically look a lot like what we think early Earth
Speaker 3: was like.
Speaker 2: So for half a century we built our entire model
Speaker 2: of prebiotic chemistry in the Solar System based on Murchison.
Speaker 2: We pictured these big, warm, wet asteroids breaking apart and
Speaker 2: delivering their life giving cargo to the early planets.
Speaker 3: That was the dominant model. But now Benu walks into
Speaker 3: the room.
Speaker 2: And Benu is the rebel, the nonconformist.
Speaker 3: Benu stands up and says, hey, I've got amino acids too,
Speaker 3: loads of them. But I've never been warm a day
Speaker 3: in my four point six billion year life. I've been
Speaker 3: floating in the deep freeze.
Speaker 2: The steady shows Binez amino acids have a much different
Speaker 2: isotopic pattern than Murchison's.
Speaker 3: So you have two ancient rocks, both from our solar system,
Speaker 3: both the same age. One says I was cooked in
Speaker 3: water and the other says I was forged in ice
Speaker 3: and radiation. And Ofully Macintosh, the other lead author on
Speaker 3: the paper, spelled out exactly what this means. She said,
Speaker 3: it suggests that the parent bodies of Benu and Murchison
Speaker 3: originated in chemically distinct regions of the Solar system.
Speaker 2: Chemically distinct regions, not all from the same place.
Speaker 3: Right. Think of the early Solar system, that big disk
Speaker 3: of gas and dust around the young Sun. Not as
Speaker 3: a well mixed soup, but as a giant industrial kitchen
Speaker 3: with different.
Speaker 2: Stations, the solar kitchen.
Speaker 3: I like that exactly. So maybe closer to the Sun,
Speaker 3: or perhaps in the main asteroid belt, you have the
Speaker 3: hot station, things are simmering. You have larger asteroids big
Speaker 3: enough to have their cores heated by radioactive elements melting
Speaker 3: their internal ice into liquid water. That's the Murchison kitchen.
Speaker 3: They're making a slow cooked stew.
Speaker 2: Okay. And then you go way way out past the
Speaker 2: frost line where it's potentially col.
Speaker 3: You go out to the benicitchen. It's dark, it's hundreds
Speaker 3: of degrees below zero. All you have are chunks of
Speaker 3: ice and dust floating in the void, and your only
Speaker 3: energy source is this constant rain of high energy cosmic
Speaker 3: rays from deep space.
Speaker 2: And the most incredible part is that the Benu kitchen
Speaker 2: is still cooking up the same stuff. It's just using
Speaker 2: a I don't know, a nuclear microwave instead of a
Speaker 2: stove top, and.
Speaker 3: Nuclear microwave is a pretty good way to think about it.
Speaker 3: But the final dish comes out the same. They both
Speaker 3: serve up glycine and other amino acids.
Speaker 2: That is the part that I just can't wrap my
Speaker 2: head around. You have two completely different environments, two fundamentally
Speaker 2: different energy sources heat versus radiation, and they both converge
Speaker 2: on producing the exact same fundamental biological building blocks.
Speaker 3: It suggests it wasn't a fluke, it was convergent chemistry.
Speaker 3: It seems that given the basic starting ingredients of carbon, nitrogen, oxygen,
Speaker 3: and hydrogen. The universe is almost determined to create complexity.
Speaker 3: It will find a way hot and wet or cold
Speaker 3: and radioactive. It gets the job done.
Speaker 2: It really hammers home that idea that the early solar
Speaker 2: system wasn't just making the ingredients for life in one
Speaker 2: special place. It was trying to make them everywhere, in
Speaker 2: every way it could.
Speaker 3: It was now speaking of complexity. There was another part
Speaker 3: of the study that I found completely and utterly baffling.
Speaker 3: And reading the paper, you get the sense the researchers
Speaker 3: were just as baffled.
Speaker 2: Oh, this must be the mystery of the mirror.
Speaker 3: The mystery of the mirror. It sounds like a title
Speaker 3: for an old detective novel.
Speaker 2: It really does. So what is this all about.
Speaker 3: It has to do with a property of molecules called chirality.
Speaker 3: Chirality which is also known more simply as handedness.
Speaker 2: Like being left handed or right handed.
Speaker 3: Exactly like that, hold up your hands in front of you.
Speaker 2: Okay, they're up.
Speaker 3: Your left hand and your right hand are perfect mirror
Speaker 3: images of each other. Right they have the same components
Speaker 3: four fingers, one thumb, a palm, but they are not identical.
Speaker 3: You can't lay your left hand perfectly on top of
Speaker 3: your right right, and a.
Speaker 2: Left handed glove doesn't fit on my right hand. They're
Speaker 2: non supermposable mirror images exactly.
Speaker 3: Many molecules, including amino acids, are the same way. They
Speaker 3: come in two forms, a left handed version and a
Speaker 3: right hand hand version.
Speaker 2: Okay, and normally these two versions are chemically identical.
Speaker 3: Aren't they in a test tube? Yes, they have the
Speaker 3: same mass, the same boiling point, the same freezing point.
Speaker 3: And this is the critical part. If you make them
Speaker 3: through a non biological chemical process, like what's happening on
Speaker 3: an asteroid, you should always get a perfect fifty to
Speaker 3: fifty mix of left and right, and isotopically, those left
Speaker 3: and right handed versions should be identical.
Speaker 2: Because they were made in the same pot at the
Speaker 2: same time.
Speaker 3: Right, if you bake a batch of cookies, the left
Speaker 3: half of a cookie and the right half of that
Speaker 3: same cookie should be made of the exact same dough.
Speaker 2: That makes perfect sense, but.
Speaker 3: Benu, of course, did not follow the rules.
Speaker 2: Benu seems to enjoy breaking rules.
Speaker 3: It does. The research team looked at a different amino acid,
Speaker 3: this time one called glutemic acid. It's a bit more
Speaker 3: complex than glycine. And they measured the nitrogen isotopes, the
Speaker 3: weight of the nitrogen atoms in the left handed version
Speaker 3: versus the right handed version, and what do they find.
Speaker 3: They found a huge difference. They had, and I'm quoting
Speaker 3: the paper, drastically different nitrogen values.
Speaker 2: Wait, what how is that even possible? If they are
Speaker 2: mirror images formed in the same rock from the same
Speaker 2: pool of ingredients. How can one be made of different
Speaker 2: stuff than the other?
Speaker 3: That is the million dollar question. I mean, it's the
Speaker 3: ten million dollar question. There is no simple, obvious reason
Speaker 3: why the left hand should be isotopically heavier than the
Speaker 3: right hand. It shouldn't be.
Speaker 2: So what's the explanation? Is there a working theory?
Speaker 3: Honestly, we don't know.
Speaker 2: Wow, the expert is stumped.
Speaker 3: I am, and so are the people who wrote the paper.
Speaker 3: Basinsky was refreshingly honest about it. In the university's press release.
Speaker 3: She basically said, we have more questions now than answers.
Speaker 2: I have to say, I respect that it's rare for
Speaker 2: a major scientific paper to just throw its hands up
Speaker 2: and say this part is really weird, and we have
Speaker 2: no idea.
Speaker 3: Why it is, and it's what makes science so exciting.
Speaker 3: It means we've just stumbled upon a new piece of
Speaker 3: the puzzle we didn't even know existed, some process we
Speaker 3: don't understand yet. Why would the mirror image have a
Speaker 3: different chemical heritage? Did they form in slightly different places
Speaker 3: on the asteroid and then get mixed together. Did some
Speaker 3: weird radiation process preferentially destroy one type of nitrogen isotope
Speaker 3: and one handedness but not the other. We just don't know.
Speaker 2: It's a genuine scientific cliffhanger.
Speaker 3: It's the absolute frontier. We thought we had a pretty
Speaker 3: good handle on chirality, but Ben was just sitting there saying, nope,
Speaker 3: look closer, you've missed something big.
Speaker 2: So let's just tally the score here. From one single
Speaker 2: teaspoon of space dust, we have a brand new recipe
Speaker 2: for making life's ingredients using ice and radiation. We have
Speaker 2: proof the early Solar system had multiple distinct kitchens all
Speaker 2: cooking up the same meal, and we have a baffling
Speaker 2: new mystery about mirror image molecules that don't match.
Speaker 3: That is a pretty good haul for one robotic space heist,
Speaker 3: It really is.
Speaker 2: But I want to zoom out now. As we always do.
Speaker 2: Why is this matter? Why should the person listening to
Speaker 2: this right now maybe second traffic or walking their dog.
Speaker 2: Why should they care about the isotopic ratios in dust
Speaker 2: from an asteroid millions of miles away.
Speaker 3: It matters because this is our origin story. It's everyone's
Speaker 3: origin story.
Speaker 2: Go on.
Speaker 3: There's a field of science called prebiotic chemistry. That's all
Speaker 3: the chemistry that had to happen before biology could take over,
Speaker 3: before the first cell. Glycine and the other amino acids
Speaker 3: are key signposts of that chemistry. Okay, what this study
Speaker 3: and others like it are confirming is that the building
Speaker 3: blocks of life were not unique to Earth. Our planet
Speaker 3: did not have to invent amino acids from scratch in
Speaker 3: its own oceans.
Speaker 2: We didn't have to diy the entire project from the
Speaker 2: ground up.
Speaker 3: No, the Solar System was a massive factory making these
Speaker 3: components in huge quantities on asteroids, on comets, and the
Speaker 3: cold and the heat, and then what happened in the
Speaker 3: early days of the Solar.
Speaker 2: System, the late heavy bombardment, everything was hitting everything.
Speaker 3: Else exactly the delivery system. Think about the Earli Earth
Speaker 3: four billion years ago. It was a violent chaotic place.
Speaker 3: We were getting pelted constantly by rocks and ice from space.
Speaker 3: We've long suspected that these impacts delivered water and organic
Speaker 3: material to our barren planet, but now we have a
Speaker 3: much richer picture. We know they were delivering a whole
Speaker 3: diverse menu of ingredients cooked up in all these different ways.
Speaker 2: It's like a cosmic meal kit delivery service for young planets.
Speaker 3: That's it Astrofresh for the Haitian eon.
Speaker 2: So Earth is getting showered with these rocks, and they're
Speaker 2: chock full of glycine and other amino acids made in
Speaker 2: both warm and cold environments.
Speaker 3: And because we now know these things can be made
Speaker 3: in ice and radiation, which are arguably the most common
Speaker 3: conditions in the entire universe, this has truly universal implications.
Speaker 2: Right because warm little ponds those might actually be rare.
Speaker 2: You need a planet of the right size, at the
Speaker 2: right distance from its star, with an atmosphere with liquid water.
Speaker 2: That's a long and specific shopping list.
Speaker 3: It is. A planet with a warm pond is a
Speaker 3: luxury item in the cosmos. But cold irradiated ice, that
Speaker 3: stuff is everywhere everywhere. It's the primary component of every
Speaker 3: common It's in the countless asteroids out in the Kuiper Belt,
Speaker 3: it's in the orc clouds surrounding our entire Solar system.
Speaker 3: It makes up the moons of Jupiter like Europa, and
Speaker 3: the moons of Saturn like Enceladus. They are all giant
Speaker 3: balls of ice getting blasted by radiation from their host planets.
Speaker 2: So if the recipe for making amino acids works in
Speaker 2: those conditions.
Speaker 3: Then the building blocks of life are in all likelihood,
Speaker 3: absolutely everywhere, not just here, not just in our Solar system,
Speaker 3: but in every Solar system, in the interstellar clouds between
Speaker 3: the stars, everywhere.
Speaker 2: That has a staggering thought. It reframes the question from
Speaker 2: how did life start here? To with the ingredients being universal,
Speaker 2: why wouldn't it start everywhere? It suggests life's potential is
Speaker 2: baked into the very physics and chemistry of the cosmos.
Speaker 3: Alison Bazinski summed it up perfectly. She said, their next
Speaker 3: step is to analyze more asteroid samples, and we want
Speaker 3: to know if they continue to look like Murchison and Venu,
Speaker 3: or maybe there is even more diversity in the conditions
Speaker 3: and pathways that can create the building blow of life.
Speaker 2: She wants to find more kitchens.
Speaker 3: She wants to find more recipes because every time we
Speaker 3: open a new rock, it seems to tell us that life,
Speaker 3: or at least it's precursors, is more resilient, more adaptable,
Speaker 3: and maybe more inevitable than we ever dared to imagine.
Speaker 2: More inevitable. I like the sound of that. It feels
Speaker 2: deeply optimistic.
Speaker 3: It's not just blind luck, it's chemistry, and the laws
Speaker 3: of chemistry are the same everywhere in the universe.
Speaker 2: So to bring it all home, we started this journey
Speaker 2: by picturing a robotic heist to grab a teaspoon of dust,
Speaker 2: a rock that hasn't changed in four point six billion years,
Speaker 2: and we end up realizing that this dust is a
Speaker 2: recipe book.
Speaker 3: A recipe book with multiple very different chapters, and we
Speaker 3: just learned to read the chapter on I don't know
Speaker 3: cold brew chemistry.
Speaker 2: We learned you don't need a warm pond to start
Speaker 2: making life legos. You can do it in a cosmic
Speaker 2: freezer with a side of gamma rays.
Speaker 3: And we learned our solar system wasn't a uniform place.
Speaker 3: It was a complex, varied chemical landscape, with different regions
Speaker 3: cooking up the same vital ingredy using totally different methods, and.
Speaker 2: On top of all that we learned, we still have
Speaker 2: a profound mystery on our hands about why mirror image
Speaker 2: molecules don't always seem to be made of the same stuff.
Speaker 3: It's job security for the next generation of scientists. If
Speaker 3: we knew all the answers, it would be a very
Speaker 3: boring universe.
Speaker 2: That's true, But I think the big takeaway for me,
Speaker 2: the thing that really sticks is this shift in perspective.
Speaker 2: Science is all about expanding the boundaries of what's possible, right,
Speaker 2: and we used to have a very narrow earth centric
Speaker 2: view of what was possible. Life needs liquid water, life
Speaker 2: needs moderate temperatures. Now we know the universe has, as
Speaker 2: the research put it, many conditions to create that starter
Speaker 2: pack for life.
Speaker 3: It doesn't just open the door to new possibilities, it
Speaker 3: kicks the door off its hinges.
Speaker 2: So here's a final thought. I want to leave you
Speaker 2: with something to chew on as you go about your day.
Speaker 2: We tend to think of deep space as empty, cold, dead, hostile,
Speaker 2: a black void where life struggles. But if this research
Speaker 2: is right, if that cold, dark, radioactive void is actually
Speaker 2: a NonStop factory for the very building blocks of life.
Speaker 3: Then the darkness isn't dead at all, It's pregnant with
Speaker 3: potential exactly.
Speaker 2: So does that mean life isn't some lucky, miraculous accident
Speaker 2: that happened on one special blue marble. Does it mean
Speaker 2: that life is actually a cosmic inevitability, That the universe
Speaker 2: is just saturated with these seeds, waiting for them to
Speaker 2: land in any halfway decent soil.
Speaker 3: If the seeds are everywhere, then the garden is just
Speaker 3: waiting to grow.
Speaker 2: Something to think about, the next time you look up
Speaker 2: at the night sky. It's not just empty space up there.
Speaker 2: It's a kitchen.
Speaker 3: It's potential.
Speaker 2: Thanks for diving deep with us today.
Speaker 3: It's always a pleasure.
Speaker 2: We'll see on the next one. Keep looking up stations,
Speaker 2: says Sets.