← Are We Doomed?
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This is Tonya Moseley, co host of FRESH air. From mail in ballots to racial gerrymandering, a lot is at stake for America's free and fair elections. I spoke with journalist Ari Berman about what he calls a final blow to the Voting Rights Act.
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My fear is that we are returning to a politics of Jim Crow in the South.
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Listen to FRESH AIR on the NPR app or wherever you get your podcasts.
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The comet had lived billions of years. It held its shape, ice, rock, dust, while planets and stars lived and died in the distance. One day, the comet drifted a little too close to the sun, whose gravity caught it. Ice boiled, a tail bloomed, pulled into closer orbit. The comet was stuck, circling our star, a carousel it couldn't escape for perhaps hundreds of thousands of years until a few decades ago, it passed Jupiter, the gas giant with a huge, huge gravity well of its own. Jupiter now imprisoned our comet, drew it so close to the planet, it briefly skimmed the outer atmosphere. That broke it into pieces like a string of beads. The broken comet stretched out over the planet, circling it still but now in a death spiral. And that's when we saw it on Earth in 1993. Humans had the temerity to name the ancient Comet Shoemaker Levy 9 after the astronomers who first spotted it. And one year later, telescopes around the world excitedly trained in to watch the comet plunge for a final time into its captor.
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All of those pieces impacted into Jupiter's atmosphere.
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The death was fiery observatories detected great plumes of destruction, sending, says astronomer Christina Thomas.
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You could see the scars of the cometary fragments going into the top levels of the atmosphere.
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For a while, we learned a lot about Jupiter and its atmosphere and about comets. But it also taught much of the world something far more alarming.
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It was also the first time that people really were able to put together stuff still hits planets
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from Nuance Tales and distributed by the NPR network. This is Are We Doomed? I'm Ben Bradford. If you were making a list of the most destructive things that could happen to Earth or have happened to Earth, asteroid is at the top. Shoemaker Levy 9 showed the destructive potential and it kicked off two simultaneous reactions. One, a new worry entered public consciousness. Movies spun up doomsday scenarios, Armageddon, deep impact. But two people around the world looked up at this risk and said, let's deal with it. And we are. This episode is both of these stories. On one hand, asteroids and their risk, how they've shaped our planet in the past and could scar our future. And on the other, a world Uniting for planetary defense. It turns out humans can come together and solve not just a worldwide problem, but a galactic one. A mere 66 million years ago, a giant rock from outer space, about the size of our comet, smashed into what's now Mexico.
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Vast devastation into the dinosaurs, Known as a dinosaur killer.
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Astronomer Christina Thomas, she's at Northern Arizona university and also partners with NASA.
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I work in planetary defense, a real thing.
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And we'll talk about what it means. But first, dinosaurs. You probably know. An asteroid wiped them out, but the level of destruction was so far beyond that. It is arguably the worst day in the history of life on Earth. Imagine Mount Everest slamming from space into a shallow ocean at a speed 20 times faster than a sniper bolt. Blistered the ground, burrowed for miles, vaporized, and caused an explosion orders of magnitude bigger than every nuclear weapon on Earth. Firing at once, the impact pushed out air with force enough to crush everything for 1,000 miles around it. Dust and ash kicked into the sky. The world turned to night. For months, an Earth that had been super warm with almost no ice froze into winter. It was bad.
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That was an extremely catastrophic event.
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What I took away from it was like, you know, we shouldn't really blame the dinosaurs for not making it through that one.
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Um, you definitely shouldn't blame the dinosaurs.
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It didn't just take out the name brands, the T. Rex and Triceratops. It killed three quarters of all the organisms on the planet. That wasn't even the biggest space object to crash into us. Recent evidence suggests 2 billion years ago, an asteroid at least twice as large as that, A fiery ball the size of Atlanta, crashed down. The kinetic impact boiled the oceans. It didn't kill much life, only because there wasn't much life to kill yet. And even deeper into the past, the Earth's earliest days included a trauma. An object, possibly another planet, collided with us. It bit deep, broke off a section of the Earth, flung it into orbit. We call it the moon. So asteroids and other space rocks have as much destructive ability as any phenomenon in our planet's history. If you shined a black light over the Earth, it would glow with impact scars. But we humans didn't know that for a very long time.
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We first discovered that there were near earth objects in 1898.
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Near earth objects, that's asteroids or comets within about 5 million miles. Right next door in space terms. In Berlin, a bespectacled German astronomer sporting a van Dyck beard used a makeshift telescope patched together partly with cigar boxes to take old timey photographs of the night Sky. Gustav Witt was looking for bright spots that could indicate far off asteroids, maybe a new planet. But on that particular morning, the photo he developed had a streak, an object skating across the sky faster than expected, meaning closer. No one knew there were objects that close other than the moon. Witt named it Eros, which defied convention because asteroids classically have women's names. Eros, though, has a unique cylindric shape. Can you just really briefly clarify the difference between an asteroid, a meteor and a comet?
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So a meteor is actually the phenomenon that you see as it goes through the atmosphere. It's that shooting star, that streak of light.
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She says they're usually small, like 3ft.
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An asteroid is the much larger rock, larger than that size, that is moving about in the solar system. And a comet is generally seen as distinct in that it has a tail.
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Dust or gas melt from it.
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The distinction between asteroid and comet turns out to be kind of fuzzy.
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A comet is an asteroid in a ballgown, essentially, right?
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And so, you know, eventually you could run out of water on your comet and it could look just like an asteroid.
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Embarrassing. Both asteroids and comets can hit Earth. But that didn't become clear until 10 years after Witt found Eros. 1908, in remote Tunguska, Siberia, a fireball erupted.
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In the stillness, this was something like five miles above the surface.
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The explosion still catapulted people under it into the air.
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You can still see the places where all these trees were flattened.
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Scientific expeditions concluded it was an asteroid that had blown up in the sky over Siberia. Christina says it created murmurs about the possibility of asteroid destruction on Earth.
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And still the threat was seen as a relatively minor thing. And then eventually it did propagate into science fiction.
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Pulp novels in the atomic age, obsessed with planetary destruction occasionally hurled an asteroid at us. In the late 1960s, a professor at MIT challenged his engineering students to show whether they could deflect a planet killing asteroid. Their proposal was hijack the Apollo spacecraft, borrow some of the US nuclear arsenal and fire volleys at the rock. It became the basis for a big 1970s movie Meteor. That meteor is five miles wide and it's definitely going to hit us. At the same time, astronomers were pointing new telescopes and photographic equipment at the sky. They mapped more of it. They found near Earth. Space littered with objects. And then in the 1980s and 90s came the biggest discoveries. What killed the dinosaurs and that it could happen again.
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We realized that asteroids have impacted the Earth. We then see a comet impact Jupiter. We're able to actually see that. And that is one of the big events that really starts this conversation.
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The fear of asteroids and the work of what to do about them began to go mainstream. Why do asteroids attack us? Many come from the asteroid belt, a huge ring of debris between Mars and Jupiter. Others from an even bigger cosmic junk pile in the outer solar system, past Neptune and beyond. My very simplistic brain thinks of asteroids as bullets shooting in a straight line toward Earth. And that is absolutely wrong.
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Right. Essentially, you know, all of these near Earth asteroids and the ones in the asteroid belt too, they're all going around the sun, we're going around the sun. And so a lot of the potentially hazardous ones are the ones that have orbits that are sort of like ours.
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Each object, Earth, comets, asteroids, spin in their own arcs. Those arcs might crisscross like an intersection where you hope two cars don't enter at the same time.
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And so we're just having this relationship where they come close to us sometimes and then they move away and then they come back.
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But if we do arrive at the same time, there's one other factor. The arcs aren't perfect. Earth has gravity. Other planets have gravity. These asteroids, as they fly around the sun, are pulled, jostled.
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It makes all of the dynamics really complicated.
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I wanted to ask you about Jupiter.
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Mm.
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Jupiter is very big, has huge gravity. I'd read that it's protecting us. A giant vacuum cleaner sucking away asteroids that might hit us. Christina says, kind of.
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It does pull things that get close to it in, and that's great.
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Thank you, Jupiter.
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But it is also causing chaos in the main belt, where most of the asteroids are.
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Damn you, Jupiter.
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And so it is the gravity of Jupiter and Saturn, Damn you, Saturn. That actually give us near Earth asteroids.
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So they're jerks, basically. Jupiter and Saturn are pulling asteroids out of their belts and spinning them into erratic, possibly Earth smashing orbits. It's frankly disrespectful. So you're saying, like, really, if we just took out Jupiter and Saturn, then we'd be good, problem solved?
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Well, you'd have to wait, you know, 10 million years for the current crop
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of asteroids to finish their erratic orbits.
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Then they'd all go away and then the problem would be solved.
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Perfect. I wasn't looking for that solution, but I'm really glad to know that it's there.
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Yeah.
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In the years before our Comet Shoemaker Levy 9 plunged into that bully Jupiter, NASA calculated fewer than a dozen astronomers around the world were searching for potentially hazardous asteroids. That was a hinge point, as we've said. Congress demanded an analysis of the threat and an action plan. NASA established a formal program to track near Earth asteroids. Along with the Air Force, it funded new programs to search the skies. And pretty quickly there was some good news about the biggest potential planet killers.
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The truly terrifying ones that you see in the sci fi films. White we know where those are and we know that those don't pose a threat.
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The bigger the asteroid, the easier it is to see the most damaging giants turn out also to be the most lumbering. Christina says we've found all of a size equal to the dinosaur killer. There are four. I don't know if that sounds like a few or a lot, but either way we're fine.
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When we look at their orbits, they're not coming anywhere close to us.
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That doesn't mean the planet's totally in the clear. We sail continuously through a hailstorm of galactic debris ranging from so small it can't breach our atmosphere to large enough. A collision would wreak continent spanning devastation below the Big Four. NASA's trying to find all the potentially hazardous space boulders near Earth that are at least 8 kilometers wide. That's like three oil tankers across. About 35 million years ago, an asteroid likely in this category crashed into the eastern seaboard. It carved the trench as deep as the Grand Canyon. The crater extended 50 miles. It's the Chesapeake Bay. That's just the crater. Waves from the tsunami it caused lapped at the base of the Blue Ridge Mountains. And that was all pretty tame. NASA says the wrong asteroid in this category landing in the wrong spot could spawn continent wide destruction propelling enough ash into the sky to cause snap winter and mass starvation. It could even send humans back to the stone age. But the bigger the asteroid, the easier it is to see. NASA thinks we've found almost all of these. Maybe 95%. Should we be concerned about the other 5%? Christina is not.
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It doesn't keep me up at night.
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She sleeps soundly because she says we can calculate how often the Earth has encountered an asteroid of this daunting size. It's on average every 700,000 years.
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Something that not only exceedingly rare, but something that we're also doing a decent job at trying to understand.
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Where they all are less well spotted are tens of thousands or hundreds of thousands of asteroids smaller than that continent ending Chesapeake Bay causing size, but still big enough to erase a major city or an entire state. As the 1990s turned into the 2000s, Congress demanded better detection of these smaller rocks and NASA expanded its search. Still, the effort was largely ad hoc disjointed. It relied on a loose international alliance of space agencies, academics, even amateur astronomers using whatever telescopes they had on hand. Occasionally, a sensational news article would briefly raise public interest. Usually a concerningly long large asteroid. Oh, it might hit Earth, only for it to sail safely by. The general sentiment, though, seemed to be we had a handle on things until that feeling of security suddenly shattered.
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We didn't know it was coming. No one knew it was happening until actually it happened. These days, it feels like the news changes every hour.
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Well, NPR has a podcast that does that, too. NPR News now brings you a fresh five minute episode every every hour of
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the day with the latest, most important
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headlines in episodes that are clear, fact based and easy to digest. Listen to NPR News now on the
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NPR app or wherever you get your podcasts.
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Every episode of it's been a minute
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NPR's what's Happening in Culture podcast starts
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by asking three questions.
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Who?
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How? Why now?
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If the culture's asking it, we're talking
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about it at NPR.
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We stand for your right to be
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curious and indulge your cultural curiosity. Follow It's Been A Minute wherever you
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get your podcasts and we'll break down the zeitgeist y topics that are filling your feed. From the light bulb to the Internet, human history has been driven by innovation, and Shortwave is exploring how the technology of tomorrow will transform our future. Would you ride in a flying taxi? Will AI models fight wars? Hear about the technological frontier every Monday on Tech Camp, the new series from Shortwave. Listen on the NPR app or wherever you get your podcasts.
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Imagine the world's worst fireworks in cities in southwestern Russia in 2013. Sparks and smoke trails seared the sky. Sonic booms rocked cars and homes.
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Residents screamed, windows exploding, things being knocked over and, you know, people were actually injured.
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Astronomer Christina Thomas says a significant meteor exploded in the sky over the Chelyabinsk region of Russia, a populated area for the first time in the age of
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social media, very famously captured on a lot of dash cams and video posts.
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People around the world saw and heard from all different angles the consequence of space rocks. Government agencies that thought they were on top of the threat found themselves caught off guard.
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This was a surprise. We didn't know it was coming. No one knew what was happening until actually it happened.
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The meteor was a fraction the size of anything we've talked about, about the length of a semi truck. The injuries were indirect, from shattered glass or the blinding light. But Christina says to the international community it was a wake up call it again hammered home what a bigger rock, not even of world ending or Chesapeake Bay causing size might do.
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That is really the final push for people to take this very seriously.
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The United nations created a network of countries, space agencies, and astronomers into an international warning network. They do drills. NASA, for the first time, created an office dedicated solely to to planetary defense. It sounds like a Saturday morning cartoon, but it is real. And Christina, who is part of the effort, says it involves astronomers, physicists, and rocket scientists unraveling two separate mysteries.
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There is how do you actually increase discoveries? And then how do you change the trajectory of an object so that it doesn't hit the Earth? And so those are the first two planetary defense missions.
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Let's take those questions one at a time. How do you discover if asteroids are threatening us? Christina says first you have to find them.
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The entire thing about asteroid discovery is that you're more likely to be discovered if you're bright. And there's two factors to being bright. There's how big you are and how reflective you are.
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Asteroids can be made of different substances, different rock, different metal.
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You know, is it more like snow or is it more like asphalt? The small, dark things are hard to find.
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Tracking begins with finding a point of light. But then it takes math and physics,
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what we call characterization work, where we try to figure out how large it is, what it's made of. In addition to trying to refine the
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orbit, NASA sorts the asteroids it finds into three categories based on size. The biggest size is anything over a kilometer wide. Those are our continent enders, Chesapeake Bay, craters all the way up to our dinosaur killers. As we've discussed, we know where most of those are, and they don't hit that often. A size down from that are the next category. Rocks about the height of the Washington Monument. Christina says this is where most of the focus is right now.
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140 meters is this benchmark in planetary defense. We're trying to discover at least 90% of those objects.
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An asteroid in this category, While it would not threaten all of civilization, if it hit a populated region, it would do massive damage, even wipe out an entire state. There are tens of thousands of these near Earth. In the vastness of space, though, they're tiny. Christina says, we've found less than half of what we think exist in this category, the state smashers.
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So that's where most of the risk is.
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But a rock's dimensions aren't the only determiners of how much damage it'll do. Just as important is what it's made of, which leads to the smallest category NASA currently tracks. A musket ball the size of a commercial airplane plummeted 50,000 years ago into what's now Arizona desert. It would have flattened some unlucky giant ground sloths and displeased the rest that were living there on what was at the time a grassy area. This object was a city killer. If there had been cities. When the dust cleared, it had left a hole 3/4 of a mile wide and 55 stories into the ground. The crater still there. The asteroid did so much damage, in part because of what it was made of. It really was like a musket ball. Heavy, dense, full of iron. It was only 50 meters airplane size. This is the lowest size that NASA currently tracks, the potential city killers. So in these the three categories, NASA's found almost all of the continent enders, just under half of the state smashers, and almost none of these potential city killers.
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We're at 9% of 50 meter objects, right? So these are hard to find.
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I don't know about you, but to me it feels like it's great that we know where the biggest rocks are. But the idea of tens of thousands of potential state smashers and city killers swirling around out there, stealthily capable at any moment of flattening us like giant ground sloths, seems concerning. It gets my personal doom meter spinning, but not Christina's.
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Right. I mean, so one of the things that you could think about is statistically, how often did this size object impact the planet? And for 140 meters, it's about one every 20,000 years. Yeah, that's a really long time.
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Even the smallest category, the city enders, only land about every thousand years. And to be a real problem, they'd have to hit near a populated area on a world that still has a lot of open space. To use a cliche, you're more likely to be struck by lightning. And Cristina feels our detection is improving rapidly. After that meteor exploded over Chelyabinsk, Russia, and the world got more serious about planetary defense. NASA dedicated new tools for the fight.
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We were able to start using space based platforms.
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Previously, all detection was done from Earth, which left one huge blind spot, literally the sun. It's a mistake to look at it with just your eyes. Impossible with a telescope. But NASA repurposed a space telescope it used for science, now for defense.
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It's looking at wavelengths where objects are warm. And so that's going to be the dark stuff that warms up under the heat of the sun. That was actually able to start to discover some of the smaller and darker things.
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Over a decade, the percent of state smashers we found doubled, which got us to the current 45%. It's rapid progress. Christina says with more on the way.
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We're working on it. Right. We have new telescopes surveying the sky.
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A new advanced observatory that's just opened in Chile could make it 10 times easier to find hazardous objects. The US did something to support it that I've never heard of. It gave the project more money than it asked for. To speed up construction, Europe is also building an array of telescopes called flyeye, literally designed like the multi segmented eyes of an insect, which allows it to capture wide swathes of the night sky. And NASA is building its own new space telescope, purpose built to get around that pesky glaring sun.
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We saw a hole. We were like, hey, we can't see in the direction of the sun because that's not where the telescopes can look. So we're going to put a spacecraft up there to do that.
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She thinks all those projects will quickly close. More of the risk. We're about to find a lot more of the musket balls. All of which I think is comforting. Detection is improving. Still, no matter how good we get at finding asteroids, it's still only half the equation. Say one of our newfangled lenses spots a state smasher heading toward Earth. That means what? We can stare at it and chart its progress as it plunges at our cities? No, that's where you need to answer the second question in planetary defense. You need to figure out how to blow an asteroid out of the sky. Before we talk about how to stop an asteroid, I want to just see what film came up with and if we can learn anything from them.
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Sure, sure.
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The first one, lesser known, my childhood brain kind of remembers, like ads on TV for this miniseries, the 90s. It was just called Asteroid.
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Tonight.
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We gotta get you out of here. The sky is falling.
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Asteroid next.
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I have vague memories of that.
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It was on NBC and I looked it up, and the solution for beating back the, like a bunch of different asteroids was fighter jets firing lasers. And it turns out it was fighting a real asteroid, which was Eros. Okay, so what do we think about that as a, as a solution?
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I don't think that's enough energy, especially for Eros. Eros is one of the largest near
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Earth objects, one of the big four, the dinosaur killers. If lasers won't cut it, what about a more powerful technology? How about Hollywood's favorite solution? Nukem. In the summer of 1998, a pair of Blockbusters released with eerily similar plots. A planet killing rock hurls toward Earth. A motley group of Americans plus one Russian cosmonaut land on it. They drill into the offending orb and explode a nuclear weapon. The films have two different results. In deep Impact, our missiles have failed. The nuke hits the comet, but splits it into two massive pieces still capable of planet wide destruction. Troubleshoot that for me.
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You know, I do think that there's the possibility of breaking up a target.
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Breaking it up into smaller deadly chunks. Shoemaker, Levy nine style. Not good. But maybe it wasn't the nuke that was the problem. It was the personnel. They don't know jack about drilling. The other blockbuster of 1998 was Michael Bay's Armageddon. So now we have oil riggers landing on an asteroid, drilling into it to plant a nuke inside. Because famously, it's easier to train oil riggers to go to space than astronauts to be oil riggers. If I do this, I'm going to want to take my own men.
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You got it.
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What can we learn from this solution?
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Well, most asteroids aren't just one big solid rock. Especially when we talk about near Earth asteroids. They're what are called rubble piles.
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Up close they look like a ball of gravel held together, she says, only by gravity.
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And so you wouldn't need any riggers, right? You wouldn't need to drill in the real world.
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That creates a problem for the Hollywood solution.
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It's actually a completely different kind of physics.
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We've checked. A few years ago, NASA sent out a scout, landed a spacecraft, a box with solar powered wings on the asteroid Bennu, 200 million miles away. It took pictures and sucked up some of the surface like an $800 million Roomba. Christina describes the texture this way.
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It was exceedingly fluffy and just very porous.
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Fluffy asteroid okay?
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In a way, yeah. In a way that was even beyond our wildest expectations.
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Fluffy meaning gravelly, holey, bad for Armageddon style drilling. Theoretically, blowing up one of these asteroids could send shrapnel raining down. Or just reform it into a new shape. Congrats. You turned a ball into a knife. It creates challenges for planetary defense. NASA does actually consider nuclear weapons part of its arsenal. The agency's website currently describes a nuclear explosion as a last resort should a cataclysmic object get close without warning. A report in 2023 called for more study of what might happen. But with the weird physics, we probably wouldn't go for a direct hit. Armageddon style. Don't explode the rock instead. Move the rock like you're playing pool. To move one ball, knock it with another.
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What if you had kind of the energy of a nuclear explosion somewhere near an object, right? Could that give it enough of a shove to change the trajectory?
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We have tested whether we can move an asteroid not with a nuclear weapon, but a giant metal punch. And what happened?
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Boom.
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what diseases medieval pee tests and cocktails have in common, you're in the right place.
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On our show, this Podcast Will Kill youl, we explore the wild world of diseases, their history, biology and impact. Today, vaccines are in part a victim of their own success. They have been so effective in preventing disease and death that we take the them for granted. New episodes drop every Tuesday on the Exactly Right network. Listen to this podcast Will kill you on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.
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For years, Christina Thomas was part of a team that wanted to try actually deflecting an asteroid, change its trajectory, what
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we call kinetic impact. Literally taking the spacecraft and crashing it directly into an asteroid.
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It was just punch it, punch it. The team pitched the project to NASA. Kristina did not have high hopes.
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I kind of had this feeling that was we're never going to actually do this, but this is a really fun experiment to think through.
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But then after the Chelyabinsk meteor blew up over Russia, the project moved forward. NASA's new Planetary Defense office moved it from concept to design.
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It became more and more real until we were actually selected as a mission.
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C
And so a SpaceX rocket fired through the atmosphere in 2021 and released a refrigerator sized box with wings called dart. The dart spacecraft maneuvered toward a large asteroid about a kilometer wide. The target though, was not the asteroid, but a Little companion circling it, a
- [31:54]
A
small moon going around a slightly larger asteroid. And that moon was about 150 meters across.
- [32:01]
C
That's right. Asteroids can have moons. And this one was the size of a state smasher.
- [32:05]
A
If something like that size hit the Earth, that would be regional devastation.
- [32:08]
C
Yeah, it'd be bad.
- [32:09]
A
And so we wanted to understand how this all worked.
- [32:13]
C
Could Dart move a fluffy, gravelly asteroid by punching it? What would happen? To be clear, neither this parent asteroid or the mini moon Christina was helping punch posed a threat to Earth. This was unprovoked, a test of the weird physics.
- [32:29]
A
If you think about an asteroid as a solid rock, then you might think this is a really easy physics experiment where you hit one thing with another thing, kind of like when you're playing pool and it just works. But we know that that's not the case.
- [32:42]
C
Imagine swinging a baseball bat at a big pile of magnets. The magnets go flying.
- [32:47]
A
It's going to throw off a lot
- [32:48]
C
of material which magnetize and attract the rest of the pile.
- [32:52]
A
That's going to give it an extra push.
- [32:55]
C
For the better part of a year, the spacecraft Dart chugged toward this poor little moon, Dimorphos, a vending machine approaching the Great Pyramid of Giza. Two months before collision, a built in camera detected its target and locked on. Two weeks before collision, the craft released a small satellite camera from Italy, space agency in size.
- [33:16]
A
You know, we're talking about a couple
- [33:18]
C
of shoeboxes, a GoPro for cosmic violence. A few hours before collision, Dart began piloting itself toward its victim.
- [33:26]
A
The camera was autonomously navigating the last section of the impact.
- [33:31]
C
With its course set, the thrusters fired and then cut. And Dart became what it was named for. Christina was on the ground watching. She was leading a team of of astronomers around the world who were measuring the effect. And what happened?
- [33:45]
A
Um, boom. There was just this big dust tail. All this material had been flown up,
- [33:52]
C
it scattered and reformed. It's not exactly like this, but imagine the pile of magnets flying into the sky and reconnecting.
- [34:00]
A
There is a lot of evidence to suggest that instead of just making a crater like you might see here on Earth, that it just completely changed the shape of the object.
- [34:10]
C
But the question wasn't, can you give Dimorphos a makeover? It was, can you move it by punching it? And the answer to that was emphatically yes.
- [34:22]
A
It was really phenomenal.
- [34:23]
C
Christina says they measured the Moon's orbit
- [34:25]
A
before and after, and we reduced that orbital period by about 33 minutes.
- [34:32]
C
So they Changed its orbit. If Dimorphos had been on a path to collide with Earth, the hope is that planet and mini moon Would have slipped past each other. Ships in the night sky. No boom.
- [34:44]
A
I think it's one of the best ways we have to mitigate a potential impact.
- [34:49]
C
But we have more to learn. The European space agency has launched its own spacecraft to go take another look at the scorched wreckage of port Dimorphos. And Christina wants to do the whole thing again.
- [35:01]
A
I would love more darts. Right, Right.
- [35:04]
C
Do it again.
- [35:05]
A
I would love to do it again on something completely different.
- [35:07]
C
Yeah. You want to punch more of them. I get it.
- [35:09]
A
Who doesn't, Right?
- [35:10]
C
Right. What if it's a metal asteroid like our musket ball?
- [35:14]
A
There's all sorts of different kinds of objects that are there in near earth space, and we don't know exactly how each one is going to react.
- [35:24]
C
The risk is not none, although it is low, that an asteroid out there could crash into us, Killing a city, smashing a state, ending a continent. There's more science, more planetary defense ahead of us than behind. There are emerging challenges, too. Satellites, countries, and businesses are launching into space have cluttered the night sky, dirtying astronomers view an annoyance on the windshield at the same time as we're getting better at spotting potential threats. Still, overall, I think asteroid and the response are a story of remarkable progress in rapid time against an unlikely but truly galactic threat.
- [36:04]
A
We can actually say, well, we need a spacecraft to do X, y and z. Back in 2004, a lot of this was a pipe dream.
- [36:11]
C
We have new telescopes on Earth and in space to find the small, dark objects that have previously hidden from us. We've developed planetary defense. We've gone from worrying about objects slamming into us to slamming things into them. Christina thinks at this rate, we are going to solve asteroid.
- [36:31]
A
I do think that we are, you know, getting there day by day to retire, basically. The rest of the risk.
- [36:40]
C
That's amazing. This is a story of not just individual nations, But a world that's so often at odds Coming together and uniting in a common cause to solve a galactic problem. I don't know why. Maybe it's because our knowledge of the threat developed, Devoid of political bickering over whether it's real or because no one has developed a vested interest in allowing rocks to smash into us. Or maybe it's because they threaten every society equally. Whatever the reason, there's gotta be a model in here that we can learn from. If we're on pace to turn back the thing that killed the dinosaurs and caused the moon. We've gotta be able to deal with other, less cosmic threats. Although, sorry, I could leave it there. But I gotta say, of all the apocalypses we chose to get good at, I can't believe it's the one that might only come around every million years. Thank you so much for listening to Are We Doomed? We are one of Apple's 2026 picks for the best podcasts of the year so far. We're still really new though, and the response has been incredible. But to keep doing this show in this way with the care you're hearing put into it. We need your help first. You can just tell a couple more people about us and encourage them to listen. That's honestly huge. You can also support us more directly@doompod.com support. That's doompod.com support and we're super grateful for everyone who's done it so far. As a thank you to our supporters, we have bonus episodes. We have a a forum via Discord where you can chat about the show with me. And we're gonna have more perks as we go. So if you've got an LA cup of coffee per month, you will want to throw at us to help us keep doing these episodes, please go to dunepod.com support next time on Are We Doomed? The moon. The moon is indeed drifting away and what to do about it?
- [38:52]
B
Blow it up.
- [38:53]
C
You can also check out all of our past episodes on YouTube. We are Sign are wedoomed odd and the anime likeness of me is spot on. Are We Doomed Is a production of Nuanced Tales. It is created by me, Ben Bradford. Our producer is Lindsay Kilbride. Our editor is Tracy Samuelson. Our sound designer and engineer is Jay Sebold. Our video animation is by Alborz Kamalzad Themusic by Dylan Dagenet. The show is distributed by the NPR network. Huge thanks to Dan McCoy, Kalia Ali and the rest of the team at NPR. And the biggest thanks to you for listening and supporting us.