The Arecibo Message and Interstellar Communication

What happens when humanity dares to shout a cosmic “hello”? Could it help alien civilisations decode human mathematics, our DNA, the blueprints of who we are? And why did we blast the 3-trillion-watt message into the stars in the first place…only to never try anything like it again? This is the story of the Arecibo message. Welcome to The Rest Is Science: Field Notes. Every Thursday, Hannah and Michael rummage through their personal troves of scientific treasure and source discoveries that explain our understanding the universe, oddities that scramble our brains, objects that hint at forces we’ll never see...and a few things that are essentially just plain cool. Expect deep dives into the science behind each pick, the spark that grabbed their attentions, and the sheer delight they get from sharing it all with you. They’ll also be tackling your questions, so email The Rest Is Science at [email protected]. ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠cancerresearchuk.org/restisscience ⁠Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠clicking here.⁠ ------------------- Video Producer: Adam ThorntonVideo & Social: Bex TyrrellAssistant Producer: Imee MarriottProducer: Becki HillsSenior Producer: Lauren Armstrong-CarterHead Of Digital: Samuel OakleyExec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Hannah Fry?

  This episode is brought to you by Cancer Research UK.

• 0:02Michael Stevens?

  Imagine this, inside all of us, billions of cells follow millions of instructions written in microscopic code. And when a new cell grows, it copies those instructions, but the smallest error can lead cancer to develop.

• 0:17Hannah Fry?

  Right. And this is the reason why there isn't a single cure for cancer, because, you know, there are more than 200 different types. Each of them have got different distinct characteristics, you know, different challenges, different mysteries. And that means that trying to cure cancer isn't like following a single path. It's like trying to map out an entire forest.

• 0:34Michael Stevens?

  That's right. And Cancer Research UK is the world's largest charitable funder of cancer research. I mean, their work spans more than 20 countries with over 4,000 scientists, doctors and nurses pushing knowledge forward to save and improve lives worldwide.

• 0:50Hannah Fry?

  You know, over the last 50 years, the work that this charity has done has helped to double cancer survival in the UK. And you have to think about, that is, that is more parents at the dinner table, right? That is more friends at their birthday parties. That is more people who are living longer, better lives.

• 1:08Michael Stevens?

  For more information about Cancer Research UK, their research, breakthroughs, and how you can support them, visit cancerresearchuk.org/RestIsScience.

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• 1:49Speaker 03

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• 2:54Hannah Fry?

  Welcome to The Rest Is Science. This is Field Notes, a sort of expedition diary, as it were, where Michael and I, we're going to trade on discoveries, on curiosities, on riddles, or questions, maybe, that have tickled our minds.

• 3:08Michael Stevens?

  That's right. That's exactly right. I'm glad to be here, Hannah. So what are we going to explore today?

• 3:12Hannah Fry?

  Well, OK, I think, given that both of us, essentially, in our respective houses, are effectively living in small museums of, dedicated to science, small shrines, shall we say, dedicated to science, I thought we could start with the stuff that is very obviously in the background. And I noticed that you've got the Arecibo message up on your wall.

• 3:32Michael Stevens?

  Oh, yeah.

• 3:32Hannah Fry?

  Can we talk about that?

• 3:33Michael Stevens?

  Yeah, we certainly can. And so you might be at home, this is my office. I'm going to move my desk so we can observe these two big posters. These are representations of the Arecibo message, which were made, like, I had these made for an episode of Mind Field. I think the best way to explain them is that they are messages that we humans sent to outer space for aliens to potentially find and read back in 1974. They were sent from the Puerto Rican Arecibo Telescope, which is no longer in existence. And the messages are still not even close to where we shot them at. Even though they're traveling at light speed, they were shot at the M13 Cluster of Stars, 25,000 light years away. So it's going to take

• 4:19Michael Stevens?

  basically 25,000 more years for them to reach that cluster. But if there's any intelligent life out there, listening for radio waves, they'll get not this nice color picture, they'll get something more like this black and white one, which is actually, if you look closely, a series of ones and zeros. So it's binary, it's a pulse and then no pulse. It's, you know, pulse, pulse, pulse. It's, it's just on and off. And there's exactly 1,679 pulses. Now, as a mathematician, what's special about that number?

• 4:52Hannah Fry?

  That is, I mean, just off the top of my head and not because I know about the Arisite message before, of course. I know that that is two prime numbers multiplied together.

• 5:00Michael Stevens?

  Oh, my gosh.

• 5:01Hannah Fry?

  This is, this is, this is the idea of, of Carl Sagan, right? Carl Sagan and Frank Drake.

• 5:08Michael Stevens?

  Yeah, Drake and Sagan worked on this as well as, let me tell you the names of everyone involved. Richard Isaacman, Linda May, and James C. J. Walker, along with Carl Sagan. They said, hey, guys, we could send a message with this telescope. We could just shoot some radio waves out somewhere. And, you know, what should it say? What should a message from Earth be? And that's what they came up with.

• 5:30Hannah Fry?

  So why did they pick something that was two prime numbers multiplied together? I mean, they're very clever sausages, these two, these two people. You would, you would think there's something good going on.

• 5:39Michael Stevens?

  Well, it might be too clever by half, as they say. That's why I had these posters made. We gave the message, not as a poster, but as a series of on and offs, as a bunch of bits, to a whole bunch of groups of mathematicians, college students. And we just told them, crack the code. Figure out what this is.

• 6:01Michael Stevens?

  Actually, I think we told them, this message has been received by a telescope operated by SETI, the Search for Extraterrestrial Life. Is it a message? And what does it say? And none of them were able to figure it out. This was for an episode of Mind Field, the psychology show I did. But being the product of two prime numbers means that 1,679 is pretty special. We also call it semi-prime, if you're the product of two prime numbers. And when you notice that, you go, man, you know, the only number that goes into 1,679 are 23 and 73. Is that true?

• 6:40Hannah Fry?

  Yeah.

• 6:40Michael Stevens?

  Is that, if you're the product of two prime numbers, you only have two, two factors?

• 6:45Hannah Fry?

  Yeah, it's absolutely true.

• 6:46Michael Stevens?

  Okay. So you might think, well, let me arrange these pulses into a grid that's 23 by 73. So if you do that with 23 columns and 73 rows, a picture emerges, a visual picture of squiggles and lines. One of them, right there, shown here, more easy to see in red, looks like a little stick figure drawing of a person. A very pixelated human body. If you however, arrange these pulses as 73 columns and 23 rows, it makes no sense at all. And you would just throw it away.

• 7:23Hannah Fry?

  Oh, really?

• 7:24Michael Stevens?

  You'd say it's noise. I know. So you have to be, you have to not only recognize the semi-prime nature of 1679, you also have to arrange it properly. But once you do that, it looks really non-random. It looks like it has some meaning to it. Okay? Now, it does have meaning and the meaning is almost comical. The way they tried to use just 1679 pulses to say a lot about us. The white stuff at the top here is the same as what you see here in the binary representation. It's ones and zeros. And if you, if you use the, the ones, if you imagine the ones are the information and the zeros are the background, you can color code it like this black one here,

• 8:07Michael Stevens?

  which is a black poster with a bunch of colored squares on it that have been color coded to differentiate all the information. I'm kind of describing this to people who are just listening. At the top, you've got what looks like a bunch of white confetti. And that's actually the numbers one to 10 in binary. But there's like not enough room up here. So they had to do two columns for all the numbers over seven. And so to make it clear that the two columned sections are their own number, the bottom row is like a bullet point. So that's why one is two dots. It's actually a bullet point, meaning, okay, here's one number, one. And then they've got another bullet point.

• 8:51Michael Stevens?

  Here's two, and then two is a blank spot. And then

• 8:56Hannah Fry?

  Oh, wow.

• 8:56Michael Stevens?

  A one, a zero, and then a one. So, okay, we're doing this like binary counting thing.

• 9:02Hannah Fry?

  So hang on. So, because I didn't know this about the binary bit at the top. I just, I just, it was like, those are numbers. Okay, fine. I never looked into it that deeply. But, okay, so thus far, even if you are lucky enough to be from the same planet that this message was sent, even if you have the same counting system, the same concept of prime numbers as these students did. Even if you know what binary numbers are, you still also then have to decode this weird extra pattern that they put in where they punctuated each one of the numbers.

• 9:33Michael Stevens?

  That's right. You also need to understand the concept of a bullet point system. Now, personally, I think that if we got a message like this, we would all work on it together. Like, everyone would come up with so many different ideas. I feel like we might figure it out, or at least someone would. Whether we all believe them or not, I don't know. But yeah, it's, it's, it's almost hilarious how hard it is to decode. This purple shape, okay, which follows next, which also, by the way, not only do you have to have the same number system and you have to be able to detect radio waves of this frequency and you have to find that it's semi-prime, you also need to read top to bottom and left to right.

• 10:13Michael Stevens?

  Except the, the binary numbers are actually written bottom to top above their bullet point. Now, the purple represents the elements that life on Earth is made out of. So it's got the numbers 1, 6, 7, 8, and 15 all kind of crunched together. And those are the atomic numbers of hydrogen, carbon, nitrogen, oxygen, and phosphorus. Okay, so we don't tell you that these are atomic numbers or that these are elements or anything. It's just that you're supposed to think, what's important about 1, 6, 7, 8, and 15? Well, if you have chemistry on your alien planet, you might say, well, that's, maybe they're made out of that stuff. I don't know.

• 10:57Michael Stevens?

  The green stuff are the nucleotides that are in our bodies, represented again by numbers representing the atomic numbers of the elements in each nucleotide. Then here, the blue squiggle is the shape of DNA.

• 11:15Hannah Fry?

  Sure, sure it is.

• 11:16Michael Stevens?

  Kind of, it's the double helix. And the white, the white line in the middle of them, it's not a line, it's a cluster of, it's two columns of white squares with some black spaces in between them. That's the binary representation of the number 4.3 billion, which is how many base pairs the human body has? No.

• 11:39Hannah Fry?

  Oh, no.

• 11:40Michael Stevens?

  It's how many we thought the human body had in 1974. It turns out it's more like 3.2 billion. So it's also got misinformation about the human body.

• 11:50Hannah Fry?

  Wow.

• 11:51Michael Stevens?

  There is something very cool about this, though. If we keep going down, you see, here's a picture of what humans look like, so that the aliens can go, wow, that's what their bodies are. They've got like four appendages and a little ball at the top of a torso. And then over here, there's a big cluster of white squares, and that is a way to represent in binary the population of the Earth in 1974, how many of these little creatures there are. And funny enough, in 1974, the number of people we believe to exist was almost exactly the same as the number of base pairs we thought were in the human body. 4.3 billion.

• 12:29Hannah Fry?

  Which are both now wrong.

• 12:31Michael Stevens?

  Yeah, so they're wrong. One was wrong all the time, one was only temporarily right. There are many, many more than 4.3 billion people now. The blue line is just a stack of squares interrupted by a horizontal line of white squares. The blue squares represent that we're talking about the height of the person, and the binary number here is the height of a typical person. Okay?

• 12:54Hannah Fry?

  When you say person, though, are we talking man? I mean, this was 1970s.

• 12:59Michael Stevens?

  That physical height is, is five feet, nine inches is what's being represented, which is the height of, drumroll, an average man.

• 13:09Hannah Fry?

  Average American man, no less.

• 13:11Michael Stevens?

  It could, it could be an average human man. I don't, I don't know in 1974, what the average global male height was. But, you know, I guess aliens will know what we told them. Now, you can't see the rest of the image because there's a big chest in the way. But underneath there's some yellow, I'm going to move it up. And the yellow represents our sun and all the planets in the solar system. And the third one is raised up a little bit higher because that's the one we live on. It, it has a special position. I'll, I'll, I'll pick it up and bring it closer so you can see.

• 13:48Hannah Fry?

  Yeah, yeah, yeah.

• 13:51Hannah Fry?

  So, okay, from left to right, you've got the sun and each of the planets. Presumably the number of dots represents how big the planet is roughly?

• 14:02Michael Stevens?

  That's right, Hannah.

• 14:04Michael Stevens?

  So the gas giants are represented by more than one square. I can't actually hold this high enough without hitting my ceiling. But we're almost done because then, oh my gosh.

• 14:17Hannah Fry?

  Well, hold on a second though, because hang on, you've got Pluto on there. There's a blob on the right, which is also now incorrect. Pluto no longer considered a planet.

• 14:26Michael Stevens?

  Yeah, so imagine if the aliens not only read in the same way that we did, understood the bullet point system, used binary, understood semi-primes. They also have to have the same astronomical definition of a planet that we have. Because imagine if they saw these yellow dots.

• 14:42Hannah Fry?

  Right.

• 14:44Michael Stevens?

  And they were like, well, maybe those are planets. And they found our solar system and they looked at Pluto and said, yeah, but Pluto hasn't cleared its orbit. So clearly we're looking in the wrong solar system. We need one that has nine planets, not eight. And then finally, at the bottom, there's a picture of the, it's supposed to be a picture of the Arecibo telescope, the device that sent this message. The M shape represents the fact that it's a concave structure. Then the, the numbers at the very bottom, I don't even know what they're supposed to represent. Let me see if I can figure that out.

• 15:17Hannah Fry?

  Can I tell you my two favourite things about the Areciba message?

• 15:19Michael Stevens?

  Yeah.

• 15:20Hannah Fry?

  Based on what you've shown us. So the thing is, right, Frank Drake, Carl Sagan, like these big dogs of space and communication with, you know, the sciences and so on, these like really, really, really cool, amazing people in history. And, and I love the idea that they're like, right, we're going to send this message out to aliens and it's going to include this representation of like hydrogen and carbon, carbon and, and like DNA and a flattened double helix and a representation of all of people on earth. And then, you know, they probably said that in a meeting somewhere and then this is what they came up with. And it's like, I mean, even as someone who understands all of those things, the great beauty of all of those scientific kind of, you know, entities of, of like humanity and, and the planet.

• 16:04Hannah Fry?

  You know, the 1970s pixelated graphics are just not really doing it for me. It's sort of, it's this, this great wonder and awe and then this absolutely completely rubbish image, like A for F for, F for, for execution. My other favourite thing about the Areciba message though, is that it just kind of rounds everything off, I think. As you mentioned, they were, they were aiming this message. You can't, you can't broadcast it to the entirety of the universe because that would just take way too much energy. So they very deliberately aimed it at this like little cluster of stars on kind of a corner of the Milky Way. And as you said, it's like 20 odd thousand light years away. And so unfortunately, by the time that this message reaches that spot, 20, whatever, 21,000, 25,000 light years

• 16:49Hannah Fry?

  time, those stars will have moved. So we are essentially broadcasting this nonsense message that is impossible to decode, even when you decode it properly, it's just a, a pile of pixelated junk to nothing. So.

• 17:03Michael Stevens?

  Oh no, wait.

• 17:04Hannah Fry?

  You know?

• 17:05Michael Stevens?

  I'd never thought about that. So. It's like shooting a moving target. You need to shoot ahead of it.

• 17:11Hannah Fry?

  Right, which they didn't do.

• 17:13Michael Stevens?

  Well, in 25,000 years, how far will that cluster have moved? Surely at least some fringe stars will still be in range.

• 17:25Hannah Fry?

  Maybe, maybe. I think in general, though, neat idea, terrible execution. Michael, that's what I'm giving.

• 17:30Michael Stevens?

  I think you're right in how you graded it. It gets an A for effort. And it gets an F for execution, but I think this is all about effort. This is not for aliens. This is for us. It's an exercise in how do we describe ourselves at the most basic level to a completely different intelligent life form? And we can think this is poorly done, but you know, that encourages us to try to do better. Oh, my gosh, it's going to crush me. I'm going to put this back away. For completeness, I want to say that the very, the squares at the very bottom represent the dimensions of the Eris Ebow telescope. Okay, I'm going to put this back on the wall before it hurts somebody.

• 18:08Hannah Fry?

  There we go. From top to bottom, incomprehensible binary numbers. You've got incomprehensible atomic numbers. You've got nucleotides. Maybe that one, that one's sort of all right. You've got a flattened double helix. You've got incorrect information about the number of molecules in human body, incorrect population data, incorrect solar system information, and a telescope that doesn't exist. Hey.

• 18:35Michael Stevens?

  You're welcome, aliens.

• 18:38Hannah Fry?

  What about the reverse, though? I mean, because we have turned on telescopes to try and hear whether there were any messages coming back. And as of yet, we haven't found anything.

• 18:49Michael Stevens?

  No, we haven't. I played my part for a long time. I lent my computer's processing power to SETI, using SETI at Home, where they process all the radio and probably other light form information they receive from their telescopes to try to find patterns, messages sent like these, not from us, but from potentially extraterrestrials. And I remember distinctly living in New York and going, I want to use my computer's downtime for a purpose. And the two things I could do were SETI at Home or mine Bitcoin. And I chose listening for aliens, and I found none.

• 19:27Hannah Fry?

  How long ago was this, that you made this choice between SETI?

• 19:31Michael Stevens?

  This would have been in like 2008, 2009.

• 19:35Hannah Fry?

  Oh, so there were still a lot of Bitcoins out there to be mined.

• 19:38Michael Stevens?

  That's what I'm saying, yeah.

• 19:39Hannah Fry?

  Yeah, you could have been a squillionaire.

• 19:42Michael Stevens?

  And I think there are still a lot of aliens out there to be found, but they're harder to find than the Bitcoins were 12 years ago, or more.

• 19:50Hannah Fry?

  Which actually was a bit of a surprise. I mean, there was some people who thought that once we turned on SETI, once we started listening, there would be a cacophony of sounds. There would be, you know, countless other life forms out there who had sent out messages like the Ares Eba message just waiting for us to tune in and hear. And there was nothing. Radio silence.

• 20:09Michael Stevens?

  Yeah, we seem to be very alone. And that raises the question of why? Like, if life is so likely to occur in a universe as large as ours, why do we have no evidence of any intelligent life but ourselves? In fact, no, no evidence of life of any kind, except Earth life. And do you have your favorite answer to that question? I can run through some of the classic ones that aren't my favorite. One is that there's some kind of great filter, that basically, in our universe, when life becomes intelligent enough, it inevitably destroys itself.

• 20:51Hannah Fry?

  I mean, this whole question is called the Fermi paradox, right? So Fermi, who was actually a big part of the Manhattan Project in building the nuclear bomb, but he was like, there seems like so much opportunity for life to exist, and yet there's no observational evidence of it at all. How is it possible that those two things can coexist? And then Drake came up with this equation to try and quantify how many potential life forms there were. He kind of breaks it down piece by piece by piece by piece, but he has this final term in it, which is about the length of time that a intelligent civilization can last for before effectively taking itself out. I don't know whether I buy that one, but it certainly feels like it a bit these days, isn't it?

• 21:31Michael Stevens?

  Well, yeah, it seems like maybe, once you've got Nuclear weapons.

• 21:36Hannah Fry?

  Which he was very concerned about, of course.

• 21:38Michael Stevens?

  Of course. It's only a matter of time before a species eradicates itself. And so, sure, intelligent life has formed all over the universe. It's just that they don't last very long to like overlap and meet each other because there's something they do wrong. They mishandle nuclear weapons or weapons of similar strength. They mishandle something about space exploration, about trying to harvest energy from their sun. Who knows? It could be that the universe is teeming with intelligent life, but it's more like we live in a zoo. They're all watching us, but they don't make themselves known. They enjoy watching to see how we get on on our own. Or maybe they have a prime directive, you know?

• 22:23Michael Stevens?

  Don't interact. Don't say hello until they reach a certain level of technological sophistication.

• 22:31Hannah Fry?

  But then there's the other option, which is that actually maybe we were just all really far away from each other, you know? Like, as demonstrated by the Arecibo message, we tried to send a message out to aliens and we've managed to point it to what is effectively, you know, a model village in another country. It's like shining a torch rather than like broadcasting a message. And it's incredibly difficult to build technology that will successfully be received by other life forms. But you know, ultimately, I think once it comes down to it, you are talking about something that is incredibly, incredibly unlikely, the chance of life itself. And you're sort of multiplying it by something that is incredibly, incredibly, incredibly large, right? The number of opportunities for life in the universe. And so, who knows?

• 23:15Hannah Fry?

  You could be anywhere between, you know, life nowhere, life everywhere, or like a small handful. I think, like, in my heart, right? I think I would be very shocked if we were really alone.

• 23:27Michael Stevens?

  The universe is old enough. There's enough stars. There's enough planets around those stars at the right distance to have liquid water. And there's been enough time for that, for life that started there to become intelligent. Given all of that, though, why is the sky so silent?

• 23:44Hannah Fry?

  Hmm.

• 23:44Michael Stevens?

  Why is no one talking to us? Are they avoiding us? Are we gross? Does intelligent life inevitably destroy itself once it gets nuclear weapons or weapons of a suitable strength? Do they mismanage their growth to other star systems? And do they mismanage the way they get energy from, say, their own stars?

• 24:06Hannah Fry?

  Do you know what? I think there's a new theory. Having looked at the Araceno message again, I think I think I've got a new theory, which is that they're out there. They they saw that message coming for us and they were like, these, these, these guys are just absolutely bonkers. Let's stay the hell away. I think I strongly suspect that might be what was going on.

• 24:24Michael Stevens?

  Yeah, we're sending out like basically horror movies to outer space. I think honestly, for me, for the last few years, I've just felt like more and more convinced that we are alone, that the universe is not old enough for intelligent, sentient, conscious life to be plentiful. I think that in a billion years, I think that when the universe is just full of little blue dwarf stars that have long lives, there'll be a better chance for life to grow. But I think that we are the ancients. I think we are the first or among the very first intelligent, conscious creatures in the universe.

• 25:08Hannah Fry?

  Well, OK, we might be alone in the universe, but here on earth, we are very much not alone because we have got some questions from our listeners, a little mailbag bit, which is going to come up in a moment after the break.

• 25:30Speaker 03

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• 26:35Hannah Fry?

  Well, welcome back from the break. Have you refueled and ready to go? Because we thought we would try something with Field Notes. We thought that we would have sort of like a mailbag, you know, like a, like an old school radio show mailbag where you can send us in things. They can be objects, they can be ideas, they can be questions, and we can, you know, spend a little bit of time examining them. So this week, we've got a couple of questions that have come in that we're going to use for the purposes of our mailbag. The first one comes in from Tony, who asks, can an expert tell the difference between a natural diamond and a lab-made diamond? And do they have different commercial value? You want to take that one?

• 27:11Michael Stevens?

  Well, gosh, I haven't prepared, but I would think that they could tell because a lab diamond would be, or could be a lot more clean.

• 27:21Hannah Fry?

  Too perfect.

• 27:22Michael Stevens?

  Like a natural diamond is going to have more clarity issues.

• 27:27Hannah Fry?

  I mean, I know a little bit. So I have this ring, which I stole from my auntie, but it's a really beautiful diamond ring. And I know it to be real because every time that I get my nails manicured, you put your hand under a UV light and the ring, there are certain stones in it, which basically fluoresce blue. And that is because inside that stone, when it was formed, you know, however many, probably millions of years ago, right? There was nitrogen in the air, an abundance of nitrogen, and a little nitrogen atom was included within the sort of the crystal structure of the diamond.

• 28:08Hannah Fry?

  And I think that that's right, you know, is that like when you grow them, when you grow diamonds in a lab, you've got this perfectly clean, excellent environment that there's like total purity. But when diamonds exist in reality, right, when they're sort of formed in reality, they are effectively a record of the atmospheric conditions under which they formed. And so you have all of these little inclusions, you have these little fault lines, et cetera. So lab, lab grown diamonds are basically way more perfect and therefore I think boring.

• 28:38Michael Stevens?

  Yeah, right, right, right. They're just carbon atoms in a diamond structure. You can, you could put nitrogen in lab grown diamonds, though. That's actually what happened when we made the diamond hourglass, which I have right over here.

• 28:51Hannah Fry?

  Oh, yeah.

• 28:53Michael Stevens?

  This is the hourglass we made that contains 200 carats of diamond. They're lab grown diamonds.

• 28:58Hannah Fry?

  Sorry, 200 carats?

• 29:00Michael Stevens?

  200 carats. A carat is, I think, a fifth of a gram of diamond. Oh, here we go. There it is. So this hourglass contains lab grown diamonds. And they're kind of a green color. They're, they're, they're very sparkly.

• 29:17Hannah Fry?

  What is it like dust?

• 29:19Michael Stevens?

  Yeah, they're very small, but see, the sparkling is really, really overwhelming. If you bring this out into the sunlight, it is very cool. And that green color comes from nitrogen that gets trapped in them while they're made. And it costs quite a bit more to get that nitrogen removed so they become clear diamonds. And we didn't do that for the subscription box, but we are going to go ahead and make a version with crystal clear diamonds. But this runs for a minute and it's, yeah.

• 29:50Hannah Fry?

  A minute of diamond dust.

• 29:51Michael Stevens?

  A minute of diamond dust. And this whole thing costs like 10 bucks to make.

• 29:56Hannah Fry?

  I have, I mean, I have quite strong opinions on diamonds. I think, I think diamonds as, as jewelry, right? Like especially like whopping great big diamond rings. I'm not into it, but maybe that's one for another episode. Give you another question. Okay. James R. asks, which scientific discovery of the last 25 years will have the most positive impact on humanity going forwards? Got a candidate?

• 30:21Michael Stevens?

  Yeah, I mean, my answer is pretty quick. I think it's going to be fusion. I think fusion that is, you know, portable and long lasting is going to be almost like a B C A D transition for our species. Energy will just no longer be a concern. People like you and I will tell our grandchildren, like, we used to have to plug things in and we used to have to, like, buy new batteries and fill our cars up with fuel and pay bills. And there were limits to what we could do when it came to big, large-scale projects like space exploration or, you know, running computers. They got too hot. They just, we had to build wind farms and it was expensive. And now it's like, there's no limit.

• 31:05Hannah Fry?

  There's also, I mean, if we did manage to crack fusion, a lot of the big existential questions that we've really been troubling ourselves with for the last few decades, I mean, essentially, they disappear overnight, right? Like, desalination becomes really, really possible. Stripping salt out of water is something that we can do. It's just really energy expensive. Then there's no shortage of clean water across the entire Earth. Also, taking carbon out of the atmosphere, like, suddenly becomes something that we can do really, really easily. Fusion has no byproduct that, you know, it's like the opposite of nuclear fission, the nuclear power stations that we have at the moment, where the waste

• 31:44Hannah Fry?

  is like extremely toxic for many, many thousands of years after we've finished with it. Plus, you are essentially sitting on, effectively, a fragile atomic bomb that you have to control very carefully.

• 31:59Michael Stevens?

  Yep.

• 31:59Hannah Fry?

  Fusion is the opposite. You leave fusion B and it fizzles out into nothing. It's like extremely safe, has no dangerous byproducts, and could effectively give us unlimited free energy. Yeah, that one would be good.

• 32:14Michael Stevens?

  Yeah, effectively, right. And it would be philosophically so profound that everything on Earth is powered by the sun ultimately. The sun warms up the air and causes the wind. It causes the currents in the ocean. It's how the plants grow. It's how we, you know, then eat the plants and get energy. But if we had fusion here on Earth, we would have brought the sun to us. We would have graduated from needing a star to not needing one. And I think that's a big stage in the evolution of intelligent life.

• 32:45Hannah Fry?

  Hmm. And it's also like the ultimate sort of like message of optimism, because we know that it works. Like, we know that it works, because this is how energy is like generated by the sun. We are effectively fusion creatures, as we already, exactly as you described. I'm going to go something slightly, slightly smaller. You know what? You win with fusion. If we get there, great, but we're not there yet. So at the moment, it's just still a pipe dream, Michael. I'm going to go for something we've already got. I'm going to go for CRISPR. There was, there was this research into bacteria, right? Like into how the immune systems of bacteria work. And they were studying these kind of like repeating DNA sequences. And they, and they realized that what this particular bacteria

• 33:26Hannah Fry?

  was able to do was like effectively chop out little bits of DNA and then make replacements in it. This is sort of like blue sky research. But then this group of, this other group of scientists were like, oh, that is, there's something really interesting in that, that you can basically edit DNA. You can go in and you can snip a bit out and change it for what you want it to be. And so they effectively created this new technology called CRISPR, which stands for clustered regularly interspaced short palindromic repeats. And it has allowed them to, to, I mean, quite literally, edit genes. And like, up until now, this thing

• 34:05Hannah Fry?

  has been phenomenally impactful in our understanding of medicine, but also our ability to, to fight new diseases, essentially. There is one example of sickle cell anemia, which this incredibly serious genetic- Condition in which your hemoglobin are not shaped normally, they're shaped like, like, sort of like a half moon, right? Like a, like a sickle cell essentially. And it can be really, really damaging. It's particularly prevalent in certain populations and it's life limiting. It's a really, really serious illness. But with the advent of CRISPR,

• 34:45Hannah Fry?

  we have been able to essentially create a one-shot treatment where you can go in. And I mean, there's other stuff on top of this. Maybe we'll do an episode about this at some point or another. But you can go in and you can edit the genes of a person who was born with sickle cell anemia in order that they, they never have to suffer from, from the repercussions of that disease again. It's really pretty amazing, I think.

• 35:08Michael Stevens?

  No, it's huge. And by editing DNA, we are creating ourselves. With fusion, we become the son, but with CRISPR, we become the mother.

• 35:22Michael Stevens?

  They're two really huge things that I think are related in a deep way.

• 35:28Hannah Fry?

  What's that Oppenheimer thing? I've become God.

• 35:31Michael Stevens?

  Yeah, I have become death.

• 35:33Hannah Fry?

  That's it.

• 35:34Michael Stevens?

  Destroyer of worlds. He was a bit dramatic.

• 35:37Hannah Fry?

  He was a bit dramatic.

• 35:38Michael Stevens?

  Lately, I've heard a lot of people say he kind of like knew that that quote would like, oops, blame me for it. Guess I'm kind of cool though, right?

• 35:48Michael Stevens?

  I love this meme because it shows the big dramatic, lapidary quote from Oppenheimer. Oh, I am, I am become death. And then, you know, you've got Truman over there being like, dude, I'm the one who dropped the bomb, not you. And then you've got von Neumann being like, what are you saying? I think you're trying to confess a sin because really you want credit for it.

• 36:11Hannah Fry?

  And I'll be honest with you, von Neumann, out of all of them was by some distance, the smartest.

• 36:17Michael Stevens?

  That's why he's on the far right end of this spectrum.

• 36:21Hannah Fry?

  Can we do an episode on von Neumann one point? Cause oh my God, that man, he is holy moly. We'll leave you there then with some grand quotes from Oppenheimer and us, Michael and Hannah, just taking him down.

• 36:33Michael Stevens?

  And as always, if you want to reach out, you can email us at [email protected]. And if you want to hear more from us, go to therestis.com/science to sign up for our newsletter. Until next time, see you later.

• 37:10Speaker 06

  The Great Game, the strategic struggle between Britain and Russia.

• 37:18Speaker 07

  We assess, Prime Minister,

• 37:21Speaker 07

  with high confidence it was Russian.

• 37:24Speaker 03

  Holding the Russians accountable is World War III. They took down a British passenger jet containing 350 people.

• 37:29Speaker 06

  Mern in the Kremlin is playing, Alex. Got to ask yourself, do you want to play or not? You're the Prime Minister. You've done nothing!

• 37:42Speaker 06

  We would need to understand the policy context. All the relevant context will be structured as a framework today and disseminated into an operation order, or FRAGO. A FRAGO that says to kill the President of Russia? Yes.

• 38:00Speaker 07

  New from Golhanger. Who is going to be able to pull this off? You're my soldier, are you? Sergeant Tom McDuff, Duffy! An audio drama journey like no other.

• 38:11Hannah Fry?

  Men like Duffy, they are our most valuable weapons.

• 38:15Speaker 07

  Devized as a technically rigorous geopolitical action thriller. We have two tight friendly KIA. Where Britain plays its strongest hand

• 38:22Speaker 02

  He's the best.

• 38:22Speaker 07

  Against its strongest foe.

• 38:25Speaker 02

  Don't do it, Duffy!

• 38:27Speaker 07

  Bear Hunt. Available now wherever you get your podcasts.