The Infinite Monkey Cage - Adventures on Ice - Darren Harriot, Liz Morris, Christoph Salzmann and Felicity Aston

Episode Date: March 5, 2025

Robin Ince and Brian Cox venture into the captivating and surprisingly mysterious realm of ice. Joining them on this cool adventure is former ice dancer Darren Harriot, glaciologist Liz Morris, polar explorer Felicity Aton and ice chemist Christoph Salzmann. From beautifully formed snowflakes to ice shelves in Antarctica our guests discuss the fascinating science suspended in solid water and how much is still to be discovered. With the help of a gin and tonic they explore the properties of ice - like why it floats and how there are 20 phases of ice, three of which were accidentally discovered by our guest Christoph. Darren shares his respect and fear for ice having learnt to dance and ice-skate on it. Liz discusses how analysing deep ice can provide a window into our past climate whilst also helping us understand our present one and why penguins can be problematic. Polar explorer Felicity explains how being able to read the colours, shapes and sounds of the ice have helped to keep her alive as she's traversed the highly inhospitable (but also incredibly beautiful) polar regions. Producer: Melanie Brown Exec Producer: Alexandra Feachem Assistant Producer: Olivia Jani

BBC Sounds music radio podcasts You're about to listen to the Infinite Monkey Cage. Episodes will be released on Wednesdays wherever you get your podcasts from. But if you're in the UK, the full series is available right now first on BBC Sounds. Hello, I'm Brian Cox. And I'm Robin Ince. And this is the Infinite Monkey Cage. Now Brian, as you can probably tell tell is very much a natural ice skater

Whereas I am so naturally clumsy. I have so much entropy that just seems to be around me all the time Why is it that I slip over on ice a lot more than you do from like kind of the perspective of physics? I reckon it's because your center of mass is in the wrong place Redshifted. Redshifted. All right, then. Well, Ice has, of course... This is what we're going to talk about today. Ice has played a major part in not merely science, but also science variety.

Does anyone here know about the Iceman? Val Kilmer. It's not Val Kilmer! No. No Top Gun, right? None of you heard about the Iceman? It's one of the greatest acts that ever used to be. A man would turn up to a comedy club with a block of ice and his 20 minute routine was him trying to melt it before the time ran out. And then he would merely write down another failure

and walk off with what remained of the ice. Has anybody actually heard of that? No. They're making a movie about him and everything. But Iceman in Top Gun. Okay. So this is my first time here. Is this the show? Very unusually. Robin's rambling introduction is germane to today's show because today we're talking about ice. At first sight perhaps the simplest

of substances yet arguably the most complex crystalline solid known to exist in nature. To explore the wonder of ice we are joined by an icebreaker, an ice shaker, an ice gyrator and an ice explorer which really ruined the alliteration of the first three unfortunately and they are. My name is Felicity Astin and I'm the polar explorer that ruined your introduction, sorry. But I also do a bit of science. I look at airborne microplastics across the Arctic at the University of Southampton and the National Oceanography Centre, which is also in Southampton. And my most embarrassing story about ice, I can't believe I'm going to tell this story on a radio program, but it's about something called the Poocicle, which I was posted. I know I've ruined the

high brow already, haven't I? But I was posted down Antarctica with the British Antarctic Survey and quite early on I was sent to a place called Sky Blue, which is an area where the snow has been scoured off of the ice to leave this streak of lovely blue ice that they use as a runway for planes. So I was sent there as a meteorologist to do weather for the planes and there were a few guys there who'd been there a while and the conditions were pretty basic and the toilet was a big bright orange pyramid tent tall enough to stand up in and the toilet was just a big bright orange pyramid tent, tall enough to stand up in.

The toilet was just a big deep hole dug into the ice with a bit of plywood around the outside so you didn't fall in it. The guys were talking about, is the broom in the toilet tent? There was a lot of fuss about the broom. I thought that's nice, they're keeping it tidy. Hygiene, it's important. It didn't take me long before I realized when I went to the toilet tent, there's this big hole, and there's this broom and it's a wooden broom but all the bristles have been chopped off it. So now I'm really confused. But if you can imagine the practicality of positioning yourself over a hole to do your business,

and everybody's doing their business in the same place. And of course, anything that goes into the long drop freezes because it's in ice. So eventually you get a sort of stalagmite of poo that surprisingly quickly sort of emerges above the surface. And it becomes impossible to position yourself around this structure. So that's where the broomstick comes in. You suddenly realize, oh, light bulb moment,

that's what the broomstick is for. It's to do battle with the Pusicle so that you can do the necessary in the long drop. So that's my most embarrassing story. Follow that, Christoph. Hi, everyone. my name is Professor Christoph Salzmann. It's funny that you mention Iceman because my surname is Salzman, but lots of colleagues and I only found out recently call me Professor Iceman behind my back. I guess it could be worse, right?

But anyway. And he does look exactly like Val Kilmer listeners. Yes, I'm probably best known for having discovered ice 13, ice 14 and ice 15. On the embarrassing side though, despite being a well-known ice researcher, I'm really embarrassed to admit that I broke my leg a couple of years ago during ice skating. Well, my name's Liz Morris. I'm a Mer Emeritus Associate at the Scott Polar Research Institute, which is in Cambridge, and I've spent most of my life working on snow and ice in various ways, mostly in the polar regions, both Greenland and in Antarctica,

and lately have been much concerned with the effect of climate change on the snow and ice there. I suppose I have to admit my most embarrassing moment I think came when I first set foot in Antarctica, which was after a considerable struggle that had gone on for about 20 years. So it was a very, very big and emotional moment for me when I first landed on Cygni Island and got out of the boat and set foot on the promised land at last. And I thought perhaps there ought to be a photograph of this historic moment and asked a friend. So stood there, posing, trying to look a bit noble, a bit intrepid, maybe trying to look a bit like Felicity, though I didn't know Felicity at the time, or maybe even a bit like Brian Cox, although he hadn't been

invented at the time. I'm glad you knew he was invented. Anyway, there I was standing there composing myself when up came a smaller daily penguin and pecked me in the knee. So I fell over and was flat on my back like a beetle upside down, waving my arms and legs in the air and unable to get up. And that was the first moment that I set foot in Antarctica. Hello, I'm Darren, comedian and radio show host. My most embarrassing moment on ice was I did a TV show two years ago called Dancing on Ice. That's not the most embarrassing part. I had to do a routine where I was sort of skating and I had to rip my trousers off To reveal a pair of really tight golden pants

They went off without a hitch. I finished a routine and while I'm on the ice This guy comes up to me and he goes oh those gold pants. I remember those I think I wore those when I did I'm a celeb that person was Matt Hancock I think I wore those when I did I'm a celeb that person was Matt Hancock I thought we should start with the definition and we made a film recently about an ice ice worlds in the solar system and we asked Several experts for a definition of ice and there was no consensus so I thought I would start by asking the question to each member of the panel what is ice? Let's start with you Christoph then and then well ice is the solid form of water right but what would what about nitrogen

ice or carbon dioxide ice so what is an ice? That's right in astronomy and the space scientists use the term ice quite loosely Frozen nitrogen when you call it nitrogen ice nitrogen ice Yeah, or if it's if it's here to you'd quite dry ice But I would argue there is only one type of ice, and that's the ice you get when you put water into a freezer. So, Felicity, what do we reckon? Well, I've come across all sorts of ice. So I've traveled across glacier ice, sea ice, river ice, lake ice.

But very rarely does the ice I deal with come out of a freezer or being artificially frozen. And it's amazing how different the characteristics of ice is. I mean, just between the Arctic and the Antarctic, a lot of people think of those two places as big white cold places that are largely the same, but they are so different to the point of if you plonked me down on some sea ice and I didn't know where I was and said, are you in the Arctic or Antarctic, pretty quickly I'd have a good go at being able to tell you accurately which end of the planet I was on because the geography

is so different and so the formation of the ice, the behaviour of it, the look of it, the feel of it is different. If you look at the history of European exploration of the Arctic, it is just a litany of imaginative ways, gruesome, horrible, lingering, long ways to die horribly on ice. I mean ice can kill you in so many ways. Yeah, so my defining characteristic is it's something cold and dangerous. Could you defend the honour of ice? I'm definitely going to defend the honour of ice.

My first contact with ice was in the form of snow in 1947 when I was just able to walk in it. I thought it was utterly wonderful, absolutely beautiful and I've never ever not wanted to be in snow. And of course I agree with Christophe, it is only the solid form of water. But the ways in which this material can build into different structures, everything from a huge iceberg to the tiniest and most beautiful of snowflakes is utterly fascinating. And it does have some properties that are almost unique

in the world and our world would be totally different for example if ice didn't float on water which is probably about the most mysterious thing that you can think of. We thought we'd demonstrate that actually we don't usually do experiments and so we got this gin and we got this tonic. So we are going to do that experiment. Can I ask a question about alcohol? What is it in alcohol that makes it not freeze? It freezes if you get it cold enough. I've had a bottle of vodka in minus 50 and it froze. So Darren what about your definition of ice then? My definition is exactly what Chris has said. It's just frozen water.

But then I got thinking, I got thinking about one of my favorite movies is a film called Demolition Man. And they freeze people and then they bring them back in the future to fight crime. And I was like, if you freeze a person, like completely freeze them, do we class that as ice? No. No. That's a frozen person. This is gonna be a long show for me. Yeah. So a frozen, what do you class a frozen,

completely frozen person, they're in a block of ice. They're not ice. Why am I being combative? What do we call, what do we call that? Oh, you could call it dirty ice. I really like the way you said that. All right, dirty ice. I love the idea of frozen person is just ice with impurities in it to you.

Whilst Robin prepares the gin and tonics, it's worth doing this at home actually, or at least floating some ice cubes on the liquid. Because I'd like to explore, Christophe, to go right to the most basic level, could you describe what it is about the way that water molecules bond together in ice that produces these strange properties? Water is a really special molecule, right? And it's actually quite a small molecule that forms bonds with other water molecules at quite long distances, and that's called hydrogen bonding. And at the end of the day, all the properties that we can discuss about water and ice, it all comes down to the hydrogen bonding,

so to the way the water molecules interact with one another. So water is obviously H2O, right? And you can form an interaction that goes from an oxygen to a hydrogen and then to another oxygen, that's a hydrogen bond. There's an analogy, you could think of ice forming as a massive game of Twister, like the party game, but the rule is that everybody grabs two other people by their ankles. That's forming the hydrogen bonds. And of course, as you grab the other people,

somebody else will grab you at your ankle as well. And that's basically how you build up a hydrogen bonding network. And that's basically what happens when water freezes. And why is it so unusual as a solid, this property, that it floats on its own liquid? That's pretty much unique, isn't it? There are other materials as well, but it comes down to the fact that water is quite small molecule, but it forms these rather long hydrogen bonds. So when it crystallizes, it keeps the neighbors a little bit further apart than it would be

in the liquid. So within the liquid, water molecules can approach closer to one another and being not hydrogen bonded. And that's simply the answer now. But I also need to say something. It's only really the ice one that floats on liquid water. Of course, we know up to ice 20 now, and none of the others float on water.

The curiosity is really the case of ice water. We should come back to that in a moment. But Liz, you mentioned that that property of ice is extremely important for us. This simple thing that we, you might be observing it now. If you have poured out a drink at home and you've got the ice cubes in it, it is worth focusing on the fact they're floating. Why is that so important? Well, I think for the environment you think for example of sea

ice which is frozen seawater at the poles in the Arctic and Antarctic is floating on the surface of the water it's not sinking down so as soon as you have the sea ice which is pretty well white you have a reflective layer which means that the heat coming into the ocean is turned back, the sun's rays. So immediately, you have a situation where you set up a temperature gradient around the globe, which is driving quite a lot of the weather and the climate of the globe.

If the sea ice sank to the bottom of the ocean, the surface of the ocean wouldn't change. It would still be dark. And you'd still get the same amount of heat coming in. So that's one way, the same sort of thing happens in lakes, you freeze the top of a lake and then that actually protects the rest of the lake and fish can live in the rest of the lake during the winter. And we wouldn't be here even, so if ice would sink, the oceans would have frozen up from the bottom and evolution would may have never happened right you mentioned this It's rather cryptic perhaps too many people you said it's only ice one

Yeah, and you mentioned you discovered three of the I found number 13 14 and 15 13 14 and 15 Because it will be surprising to many there are different forms of I yeah Why well the various different forms of ice. Yeah, why well the various different forms of ice It's just the water molecules They pack differently with respect to one another and obviously as you go to higher pressures They will pack more efficiently and then then you get these high density Phases of ice which which you find in the solar system actually and you actually find some of them on earth as well So there's some there's some diamonds and obviously diamonds form under enormous pressure

And when a diamond forms and there's a bit of water Inside the diamond it will be I seven for example and due to the way we experience the world We think of it is in one way And this idea of actually going closely that this is well No, there's there's ice one ice two ice three ice four I know that is how far up do we go with the ices, first of all? I mean, it makes a lot of sense. I mean, a lot of the ice that I come across in the Arctic,

in the Antarctic, glacier ice, for example, it's been under huge amounts of pressure for a very long time. So you get ice that's different color. The different colors and shades of blues and purples and pinks that you can get in different densities of ice are, you know, unbelievable to see. It's absolutely spellbinding. And you can tell by the color of the ice roughly how old it is.

You know, the older the ice, it's sort of blue because it's had a lot of the air pressed out of it because it's been at the bottom of a glacier or something like that. And if you take some of that really old ice and put it into your gin and tonic, it's very explosive because those tiny little air bubbles that are left inside the ice are suddenly released with this mini explosion. So it's, yeah, interesting to put it in your drink. I mean, while we're on the subject of ice bubbles,

I don't know whether people know, but there's been a very, very big and exciting ice core drilling project going on in the Antarctic called Beyond Epica, and they have just managed to reach bedrock at 2,800 metres below the surface, so that's a really long ice core. And at the bottom of this ice core, we have information from the period, so more than a million years ago, and that information comes from the bubbles that Felicity was talking about in the ice. If you extract the air from that, that is the air, and we get the chemical composition of the air that was that old. And we can see, for example, what carbon dioxide levels were like then.

And we also know what the temperatures were like there. So we can start looking at the change in the ice ages, back and forth, back and forth, cold and warm, going back over a million years. Well, while we're on the basic properties of ice. So the fact that it's slippery, so that's an unusual thing if you think about it for a solid. It's extremely slippery. Why?

There is this layer of sort of a thin layer of liquid water on top of the ice. People call it the quasi-liquid layer. So the way to imagine this, you know, you have a crystal and all these water molecules and basically everybody wants to be on the inside, nobody wants to be at the surface, so in a sense they are all struggling to get back into the bulk of the crystal and that means they are more mobile and the water molecules being more mobile at the surface just means we can skate on ice. And can you skate on ice? I mean what heat did you get through to Darren? Let's find out. I think I lasted eight weeks. I did.

Come on guys. Yeah, you never trust ice at all. We'd just be standing on the ice just chatting and then one of them, and then they'd freeze and then you'd them, and then they freeze and then you start laughing and and that was it for out yeah you just honestly even when there's like ice outside on the pet I get so nervous I get so scared but that was because of that show you're voluntarily going on ice and that's why I'm here when you talk about how much you love ice and snow and I'm sitting here going what is going on like Do you make snowmen? Yeah.

There are some places where it's impossible to make a snowman. So if you get really close to the South Pole area of Antarctica, the snow gets so dry that it won't actually stick together. So if you've got a handful and try to make a snowball, it just remains. You can't even make a snowman.

You can't make a snowman, it's impossible. Yeah. Is that what makes it sort of stick to you? Sometimes you've got ice that really sticks to your hand. The temperature needs to be right. Yeah, if the temperature is too low, it won't be sticky anymore. If the temperature is too high, it's not good for skating either because then the skates have to plough through this liquid layer. So it's like just the perfect temperature, which is I think at minus seven degrees Celsius, which is just the perfect temperature which is I think at minus seven degrees Celsius which is just the perfect temperature for ice skating. But there's a show that they should do that'd be better than skating on ice and that is trying to move across very thin ice like ice

when you've just when it's just started to form and you've got this tiny it's not even a centimeter It's not even a centimeter. Yeah, my hand can't. But it really sort of bends and stretches. So we used to, again, there's not much to do when you're on an Antarctic research station in the winter. So you've got the ice starting to form. And so we used to put on these dry suits and have a race over thin ice. And you try and sort of spread your weight out onto the ice. And you would watch people as they're sort of pulling themselves across the surface of the ice

that the ice would be bowing underneath them and it's incredibly elastic and it would take a while before someone would do something like putting their weight too much on one hand or one foot and they'd fall through and then it's impossible to get back up onto the ice. But then... Who is it? Percentage-wise, how many go out and how many come back in terms of... The drool on your face as you said that as well.

Suggested it was never you that fell in. The ice didn't have to get very thick. I remember clearly there was a chart by my desk, because I was there as a meteorologist and so one of the charts that I had behind the Met Desk was ice thickness and things that you could do on ice when it got to different thicknesses and I remember clearly that it said that you were able to land a plane on ice when it was 30 centimeters thick. Now I cannot believe that to be true. I've never tested it in any way to know but that just boggled my mind.

That sounds like a Ryanair thing. In terms of material Christophe, as you said it does sound rather thin to support to support an aircraft Is it is it a strong material as materials go? Yeah, it's it's a strong material. I mean it is it is all quite soft glaciers flow, right? It's it's forgiving with respect to to defect. Yeah, I wanted to talk about that actually the glaciers that so Could you describe because we I suppose you tend to think of them as just solid blocks of ice but as you said that they flow they're dynamic could you give the picture I suppose it's the best analogy

is of a molten metal ice is actually in in the normal environment it's very close to its melting point so if you if you think of it like that, it's a material which is quite stiff, but it does flow and it also has another property which is that when it comes up against a bump on the bed, that it's flowing down, it can actually melt on one side of the bump because of the pressure it exerts and then that melt water can refreeze on the downstream side of the bump. So it's got another method of moving downhill which is basal sliding because of what we call regulation. And that property, if anyone is listening is doing I suppose GCSE or A-level chemistry,

the idea that you put a solid under pressure and it melts is an unusual property. It is and and Kristoff will just say well you know this is we're talking about ice one here, not a fancy one. So all the other ices, the melting point actually would go up as you increase in pressure, it's really just the ice one that's the odd one out. And why is that surprising that you put it under pressure and it melts? I mean it comes down to an equation in thermodynamics. It comes down to the fact that it floats on water. That's the reason why it melts at lower temperatures as you squeeze it a little bit. But you only go around to 2,000 atmospheres and then the trend is reversed, then the melting point starts going up and if you go to

around 20,000 atmosphere you reach room temperature. So you have ice at room temperature. You go even higher, you can have ice at hundreds of degrees. So in like some of the gas giants like like Uranus you'd have ice maybe at 5,000 degrees. You said only 2,000 atmospheres and only 20,000 atmospheres and the temperatures room temperature. Yeah I mean 2,000 atmospheres is what we do easily in our lab right I mean that's easily achieved. The pressure changes dramatically. Felicity, when you are exploring, when you're going out there,

what are the factors you're having to take into account and indeed the factors that are taken into account when someone goes, right, we have to make the most effective icebreaker? If you're out on sea ice at a high latitude north, so in the middle of the Arctic Ocean somewhere, the ice breaks open because it's constantly moving. There's not solid land under your feet, you're walking across an ocean, so it's just a very relatively thin skin of ice on the top and it's constantly being moved around by the ocean currents underneath it and the atmosphere above it. So it gets pushed together and it gets pulled apart and in places where it gets pulled apart to reveal the water underneath,

it steams because the air temperature might be something like minus 20, minus 40. But the seawater doesn't get colder than maybe a couple of degrees below zero, something like that. So it's much hotter than the air above it. So when you're traveling across sea ice in the Arctic, the first sign of trouble of there being open water up ahead, which is your absolute nemesis if you are a polar skier trying to get across an area of sea ice, is if you start to see what feels like mist or fog up ahead, then you know that that means there's open water up there and you want to avoid it at all costs.

The whole time that you're traveling through ice and it doesn't matter whether it's a glacier or whether it's sea ice, you have to learn how to pick up on the cues that you're seeing around you in that environment. And that, the open water, so the prevalence of open water. So I think you mentioned that the North Pole now is pretty much inaccessible. Perhaps it's easier to go back to the first, the first time someone indisputably went from solid land to the North Pole across the surface of the Arctic Ocean was Sir Wally Herbert who did it in 1969, 9th of April. And the reason why that wasn't hailed as a great achievement that it indisputably was is because just a few months later Neil Armstrong made the step for mankind onto the moon. So we almost reached another planetary body before we got to the

very top of our own. I mean, I think that speaks volumes about how difficult this environment is to survive. What kind of sounds are you hearing out there? Yeah, sound is really different, but it's more about the temperature that you're in. So in the extreme cold, if you're walking through snow, for example, snow gets much squeakier depending on how cold you are. So if you're down below minus 40, it sounds like you're walking on polystyrene. Eek, eek, eek, eek, eek, eek. That kind of thing, yeah. Whereas if it's warmer, then it sounds different.

Now do the sound. You can't just do the sound for one of them. Pum, pum, pum, pum, pum. There we go. That's much better. Is it the case that now it is not, it's probably not possible to repeat that feat to the North Pole? I think the problem is there's so much open water and it's so

difficult to even get onto the ice from the land and do it properly you know not just be put in by an aircraft that I think it's just not feasible to do an overland crossing. A good colleague of mine put it as explorers we're not chasing firsts anymore we're chasing lasts. The last time somebody went on skis from land to the North Pole was in 2014. Probably within the next 20 to 30 years it will be a navigation route for very big container ships. So yet another way the ice will kill you, you get run over by... I don't think you actually meant traffic. I thought it was just an analogy. No, no. I mean traffic like in the English Channel. Yeah. But this is of course the primary

difference between the two poles right there's no land up there the North Pole is just we just think of it as solid because in most of our lifetimes it's been frozen but it won't be in a few decades time it'll just be an ocean. Yep that's right. Where's Antarctica? Antarctica is a land continent although it's a bit deceptive because although at the moment you you look at it and it's a it's a great dome of ice you know thousands of meters thick in fact we've done enough of surveying of the underlying rock to realize it's in fact quite a lot of it is sitting on islands and is sitting on something which is below sea level. So once the Antarctic ice sheet in the western part

starts to lose mass, it could lift off from the seabed and then we'll sort of have situation where instead of being constrained by the mountains and valleys underneath it, it's just floating and can float off. So, in fact, when you try to do sums about how soon it might be before we lost the Antarctic, it's very difficult to do, in fact things could happen a lot faster than just simple calculations about how long to melt that mass of ice. Although people may not care that explorers can't plant their flag at the North Pole anymore, the importance of the story is that it really illustrates how quick, how rapid this change has been. And that's the big message about climate change. These changes are being on such a large scale and in such a short period of time. How can the rest of the ecosystem catch up with that? And that's why people are

really concerned, particularly about the Arctic, which is changing at a rate three times faster than anywhere else in the world. So you know you're really visibly seeing it. Can I just add to this fun section of our chat that people who believe the earth is flat, they think it's ice. That is that's the reason why we don't fall off the earth. Just wanted to let you know the sort of friends I have. Is that in for balance? Kristoff, we've talked about ice one in some detail.

Oh, we're not going ice one in some detail. Oh, we're not going to do all 20 hours. You discovered three, as you mentioned. So can you describe those three that you discovered? I mean, it was very special to my heart, right, because I found them one day. And I was just I was working in the lab, you know, changing pressure and temperature. And then, you know, I suddenly made these new forms of ice. And then it was a bit of a disappointment after that actually, because I tried to reproduce

it the next day and I couldn't anymore, right? And that's where my frustration set in. And then it turned out actually in hindsight, it took me quite some time to figure this out. And it just turned out on that day when I made ISO 13, someone messed with the water supply at the department and they mixed in a bit of acid, right? And that little bit of acid did the trick which allowed me to discover ISO 13, but I didn't know there was any acid, right? So only months later I thought, you know, why don't I just add a little bit

of acid to water and then I could make it and I could make it even much better than Than before I had a similar experience over Christmas. I made a brand new cocktail called a mojito Rita Yeah, unknown to man and the next day couldn't remember how I made it These different forms of ice What would they look like? Would any be obviously different or do you have to do crystallography to discern the structure? So most of them are white, right, it needs to be said. You need to do crystallography to really figure out the differences. However the ice 18 and the

ice 20, they are quite exciting because people think they would actually be black. Oh really? Because they are so-called super ionic forms of ice. So what happens in those is that, I mean, the water molecules are H2O molecules, and the hydrogens are typically bonded quite strongly to the oxygen, but in super ionic forms, the oxygen say goodbye to the hydrogens, and they just float away.

So like electrons would in the metal, and that's when you get black ice, as they call it. And I think there's a theory that they may play a role in the ice giants like Uranus and Neptune. Absolutely, because they are conducting and it has an impact on the magnetic field of Uranus for example. And the discovery is quite significant because it turns out that the melting point of ice is even higher in temperature than we previously appreciated because the ice can go super ionic. That's a way for the ice to pick up some additional entropy. We spoke about entropy earlier.

Picking up entropy means we're shifting up the melting point even further. So we are really talking thousands of degrees in terms of melting point for the ice. Ice 20, for example. Under what pressure would that then? That's hundreds of gigapascals, right? Okay, let me... Right, so it's a hundred thousand million atmospheres. Exactly, yes. These pressures are very hard to achieve on Earth and they have been done with laser pulses, so you just need an incredibly powerful laser source. This is great Darren, isn't it? This is James Bond's day. Bond villain. I'm sitting here smiling going, I love ice 20.

Yeah. I didn't know about all these different types of ice. Do you think there could be more? Or do you think... Absolutely, yeah, yeah, yeah. There's got to be a much larger number. So there's a group, they do computer calculations and they've predicted how many forms there could be and I think they were up to 19,000 different forms of ice. It kind of loses its being a special. Isn't it astonishing? It astonishes me from this simple molecule that there

what do you say, 90 different ways of arranging. But the simplicity is key right because if it's a simple molecules there's just lots and lots of different ways how you can pack it so that's that's really key it comes down to the simplicity at the end of the day that opens up the complexity if that if that makes sense yeah Liz I want to just a little bit about because we've talked before me in any app time but about also you know this the sensory experience of like, you talked about your first sensory experience was falling over after being attacked by a penguin.

But after that, the fact that when you are in that environment, your experience of what you see and what is available to you is different to what we are seeing out here now. I think there's a sort of a romantic sort of connection to the purity of it and the simplicity of it I think in in my case I was I was very glad to be in what I felt was a

Very simple world in which I had none of the the difficulties of everyday life I was just going out into the Antarctic. I had my tent. I had, there were two skidoos, three sledges full of food and fuel and scientific equipment. I had my companion and it was go. And there was nothing else that we had to worry about. So for me, the ice and snow of the Antarctic is associated with complete freedom and also with a simple task. I mean it was a difficult task many times because you were trying

to do things with frozen hands, frozen feet, you were trying to make quite difficult measurements, you know, the computer started to fuss about because it was at minus 40 and it didn't like it you know and then the generator wouldn't start if it was below minus 28 and all these other little problems but compared to not a little problem is it the generator but for me you know I have to say just in case there's anybody out there in the rather dark audience who's dreaming about being a scientist in the Antarctic, go for it. It's the most wonderful experience and being a physicist, I'm going to put in a plug for being a physicist now, it's the best possible preparation, the best possible

career you could have for looking at the environment and you know I just felt all the time I was doing what I was born to do. And by the way, Liz is a total pioneer. You know, you are my hero, Liz, because you blaze such a trail, particularly for women, that you're amazing. But when you're out in these landscapes and you're seeing the true forces of nature unrestricted, you know, you're seeing blocks of ice the size of apartments being thrown around, and you're seeing crevasses opening up and ice moving, it really does give you a whole new perspective. And I think that's why a lot of people when they go into the polar environments, find it quite a spiritual experience, because it changes your perspective you're looking at different different scales of things yeah I think

I had a friend once who who remarked of somebody who was making a bit of fuss about life that what they really needed was a bad twin otter landing and I think I think that is true I think you know if you've been absolutely scared out of your mind it does reset things quite a lot Especially if you go god that landing was absolutely terrifying. I'm gonna go to the loo Before you even get to the golden pants, right Do we need to go straight to? Are we out of time? I don't want to draw these two close actually.

No, we haven't talked about the noise of the ice as well. Well we could just meet you. Oh yeah. Oh yeah, let's just talk about that. I think the one thing you don't want to hear is a crack, a sudden crack, because that usually means trouble. What is very, very nice is to be lying in a pyramid tent with the swish of the ice crystals blowing against the canvas of the tent and to know that you're snug and warm and whatever else is going on outside, you've got it sorted and you know, you've got a nice bowl of,

well, munch we call it, inside you. You're warm, you're dry and all is well with the world and you just hear this swish of the ice crystals coming against the tent. That's the best sound ever. The diamond dust coming down and the beautiful smooth surface and the sledge running beautifully over the surface and enjoy it. And then the penguin turns up, you go, not again! How do you feel about that, Dara? If someone comes to you going, we're going to do a new version of, you know, skating on ice, whatever it's going to be called, and they're going to do it on very, very thin ice,

which is entirely trustworthy from a scientific perspective. Are we going to see you on that particular show? Yeah, I like the idea of that actually. Me and Matt Hancock just hanging out. One leg and even a pant. I don't know why I said that, that was weird. I don't know why you said that. Two men, one pair of pants.

I can see it. Right, thank you so much. We asked the audience a question as well. And we asked them, who would they most like to cryo preserve and why? What you got there Darren? Okay. Prince Andrew. Oh. To check on his sweat glands.

Oh yeah. Next one. My bank account. If it's been frozen it will explain why the balance never goes up. Andy Jones makes a very good point. So it's a what would you most like to discover encased in ice? The Arctic. Yeah that's very good. Thank you. My ex-husband so I can leave him there. Who or what would you like to discover encased in ice? An ice cube ultimate hiding place. Yes, that would be good. But it's see-through. Not if it's super ionic ice. Oh, the black

ice. It could be encased in super ionic ice. Then it would be super ionic ice though, wouldn't it? It wouldn't be an ice cube. Well, we got here? A heater because things can only get wetter. Well done. So thank you so much to our panel, Liz Morris, Christoph Saltzman, Darren Harriot and Felicity Aston. Next week I am very excited because as some of you might know, we are big fans of wrestling. And in previous shows, we have done such wrestling specials as bats versus flies and cats versus dogs. But we feel we've been getting too small. So next week, we are going to have a battle of the planets where two gas giants take each other on.

We are seeing Saturn versus Jupiter. Brian, which one do you think is going to win? Jupiter. No, I don't think it will, because I think the hula hoop of Saturn will be used in some kind of way. Thanks very much for listening, and I hope you've enjoyed yourself. Oh, did I? Happy birthday, happy birthday, in the infinite monkey cage. Turned out nice again.

Strong message here from BBC Radio 4. I'm Armando Iannucci. And I'm Helen Lewis. A comedy writer and a journalist teaming up like a pair of unkempt and unlikely superheroes. Our mission is to decipher political language. Stress testing to destruction those used and abused buzzwords and phrases. Finding out what they really mean. And looking at whether they're meant to deceive us.

Or to distract us. Or to disturb us. And our pledge is to help you spot the tricks of the verbal trait. But be warned, this series does feature strong political language that some listeners may find an inverted pyramid of piffle. Strong message here from BBC Radio 4. Listen now on BBC Sounds.