Instant Genius - The hidden ways ocean currents change our world, with Helen Czerski

Episode Date: May 28, 2023

You may have heard the phrase ‘we know more about the moon than the deep sea’ – it’s now an old phrase, dating back to 1948. In fact, we actually know quite a bit more about the ocean than you might think – which physicist and oceanographer Helen Czerski shows in her new book Blue Machine. But it’s still full mysteries, and that’s why Helen says that the secrets of the moon and the ocean are incomparable, because when it comes to the ocean there is just so much more to know, and we urgently need to uncover more. In this episode we speak to Helen about some of the secrets hidden – and found – in the ocean’s currents, including shipwrecks and missing planes, what we’ve learned from rubber ducks and Finding Nemo, and the swirling currents in underwater rivers and waterfalls. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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Music just as the artist intended. Visit name audio.com to learn more. And welcome to Instant Genius, a bite-size masterclass in podcast form. I'm Noah Leach, news editor at BBC Science Focus magazine. You may have heard the phrase we know more about the moon than the deep sea. It's now an old phrase dating back to 1948. And in fact, we actually know quite a bit more about the ocean than you might think, which physicist and oceanographer Helen Chersky shows in her new book, Blue Machine. But it's still full of mysteries and that's why Helen says that the secrets of the moon and

the ocean are incomparable, because when it comes to the ocean, there is just so much more to know, and we urgently need to uncover more. In today's episode, I speak to Helen about some of of the secrets hidden and found in the ocean's currents, including shipwrecks and missing planes, what we've learned from rubber ducks and finding Nemo, and the swelling currents in underwater rivers and waterfalls. Helen, I love the line in your book that says, the more you know about the ocean, the better it gets. So what's something that a lot of people don't know about the ocean, but you think they should know? Well, it's that the ocean has its internal structure. There's this kind of picture that it's just a big blue pond and it's all the same everywhere,

but actually, even though it's all water, that water is different in different places, and there are huge boundaries between different types of water almost. You know, water with very different characteristics, and there are kind of moving islands of water that move around inside the ocean. There's all this structure in there that's doing stuff. That's the one image I would love to place in people's heads, and it's not just a big empty pond of just the same stuff. It's got an internal anatomy and it's doing things.

there are a lot of big unknowns about the ocean so you talk about it having surprises up its sleeve and we have a lot of unanswered questions so what are some of these big questions that we're yet to discover well actually before we get on to the unanswered questions i have a right be in my bonnet about something that if you will permit me i will have the small rant which is that we don't know everything about the ocean but we keep trotting out this phrase that we know more about the moon than we do about the deep sea. And that is not true. It is categorically not true. And it undervalues the ocean hugely because it compares it to this dead, empty place that hasn't changed for two billion years. So actually, we do know lots of things about the ocean. It's not the case that the whole thing

is just one big mystery. But there are still lots of fascinating things to discover. When it comes to the big questions about how it works, there are questions still about how the energy flows around the inside of the ocean. You know, there's a lot of energy in turbulence, for example. and actually energy budgets are a really important thing. Because the ocean is not all the same, energy is something that can stir it up. And so tracking the energy around the ocean is really important. And also tracking the gases, it's all these invisible passengers of the ocean. You know, tracking where oxygen in the ocean is, for example, and exactly where the carbon dioxide is. Oxygen is actually a really big issue. You know, we know that the amount of oxygen in the ocean

is decreasing in the deep ocean by 2% over the last few decades. I can't just remember the numbers. we don't know enough to follow it around. You know, we can't follow the breathing processes of the ocean. So there are some really quite fundamental things to do with the resources in the ocean for life, things like oxygen, that we can't see them all yet. And they're really important questions. Are we likely to find out the answers to some of these questions ever or soon? They're definitely answerable questions. The thing about the ocean is it's really, it's tricky to study, partly because it's so large, and it's doing different things in all these different places, and partly because it's tricky to access. You know, we're land mammals we can float about on the surface, but we really need to be looking and measuring in lots of specific places in the ocean. And that means going on ships, which are expensive. We're not in a situation now where the robots can do this for us. And there's a couple of reasons for that.

One is that we just haven't developed the robots, although that's happening. It's a lot of work to build little autonomous machines that will sail around the inside of the ocean and the top, actually, and monitor things. But it's also that sometimes you just need humans to be there. You know, these processes are really big things. If you just need to measure the concentration of dissolved oxygen, a robot can do that. But if you have to make decisions about how to measure a really set of complex processes, you've got lots of scientists working together, you still need humans on ships. and ships are obviously a rare resource. You know, now there's an increasing concern about the carbon footprint of those ships,

even though, you know, when I go out to sea, I am studying carbon flows in the ocean, I'm still spending carbon to do that. And you talk about it being this vast, incredible system, which absolutely is, and something that it's not easy to access for us being land-dwelling animals. So how do you actually go about mapping the Earth's currents? It's not an easy task. So it's actually quite interesting because the most effective way at the moment of measuring global currents is actually from space. I mean, it sounds crazy that something that, you know, we're talking about flows in some cases of perhaps only a few centimetres per second, a few metres per second in some cases.

You know, you think surely you have to be there with something in the water to measure that water flowing. And sometimes you do. But actually, if you go out into low earth orbit and you look down on the ocean, we now have, satellites that can do this incredible thing, satellite altimeters, that can measure the height of the ocean surface. So the average, so you know, if you if you average out the waves, the ocean surface has a shape that isn't just a sphere. It's got these lumps and bumps in it. And the lumps and bumps are there for several reasons. But one of those reasons is because the water is moving. There's different ways this manifest itself. But one simple way to think about it is that, you know, in the North Atlantic, there's this big merry-go-round, big sort of roundabout where, water is going clockwise around the North Atlantic. But as it goes around, you know, the spin of the earth means it's being pushed into the middle. So it does get pushed into the middle. But then what happens is it piles up and makes a little hill and then think water tends to fall downhill. So you get this balance where the current is going around the outside, but there's a hill in the middle. And the

existence of that hill and the slopes lets you measure the currents. And, you know, the satellites that do this can measure the average sea height to less than a centimeter, it's absolutely astonishing. But if you measure the lumps and bumps in the sea surface, because of this relationship with water moving and gravity, you can actually tell where the surface currents are because the water piles up. And the currents go kind of along the slope. They sort of go parallel to the slope. And so we actually can map ocean currents really well from space. And because satellites are going round and round all the time and they can see a very wide area. We can look down on the planet and we can, we know where the currents are doing what. You know, it's astonishing thing, but this little bit of physics gives us

the way into doing it. And is it true that rubber ducks played a part in this, or is that a kind of myth that needs to be busted? Well, the rubber ducks are one of many. So it's been known that this con, so flotsam and jetsam has been known about for a long time. So floating things like that, they tell you where, where things end up. So there was a very famous, I mean, the, this has happened lots of times. It's not just the rubber ducks, but one of the most famous cases was a container fell off the side of the cargo ship, which happens sometimes. I don't understand how it doesn't happen more often, because if you look at those cargo ships, they're stacked up in this, no one, you know, your mother would never let you stack things like that up in your bedroom,

right? Because it would fall over, but apparently the ships manage it. So occasionally one of those will fall off, break open, and its contents will sort of spread. And the interesting thing about that is you put lots of things into the ocean at the same place. and then you can see how many different places they end up in. And they can travel a very, very long way. And there are some examples of, you know, the exact shape of the object. So things that are one shape will tend to go one way, and things that are a different shape will tend to go in a different direction.

So the rubber ducks were one famous example. I think it's happened a few times, actually, where there was one particular container, and then people were finding these rubber ducks for a long time. But it's happened, you know, there's shoes, there's cases that specific islands where all the right-hand shoes have washed up on one beach and all the left-hand shoes are on another beach. So these traces, they act as tracers, and they have been a very useful way of learning about currents. But actually, we do that

now with instruments deliberately. We put small floating things in the water with trackers on them and we can see where they go. And actually, a lot of this science was very useful when the Malaysian plane MH370 went down and they wanted, you know, bits were washing up and they wanted to work backwards to where the plane had actually crashed. This was the sort of science they were using that scientists had already put drifters in those areas and they could say well you know if something washes up here it might well have come from over here back there so yeah so drifting things are very useful when it comes to tracking where the ocean's going and it can make you know even the depth so if you if you drop a small thing the big thing in the same place they will end up in different

places because the small thing gets carried by the wind and the surface and the slightly bigger thing gets carried by the water flows deeper down so there's all this wonderful subtlety in the water's movement. And I think that was one of the things that sort of surprised everyone about the difficulty of finding that plane. One was that the ocean is very big. The other is that it came as an astonishing thing to a lot of people that all the stuff didn't end up in the same place. Are there parts of the ocean where the currents don't reach, the kind of deepest depths and underwater caves, or is it kind of this constantly fresh moving system? One of the sort of ideas about the ocean that doesn't get talked about often enough is that the surface is quite separate to the deep in quite a lot of cases.

So the surface of the ocean, and it can be defined in slightly different ways depending on what you're doing. But, you know, it's a warm layer. It's mixed up by the wind. That's the bit that we interact with. And that's the bit that the wind pushes along. So wind-driven currents can be perhaps a few hundred metres deep. I think the Gulf Stream might be a kilometre deep in places. But, you know, it's up near the surface.

and that's getting pushed around by the wind. But actually, if you go further down in the ocean, you know, if you go 4,000 metres down, there's no wind to push on that. But it does still move. And the reason it still moves is that density is pushing things around. So, for example, in the North Atlantic, in between Iceland and Greenland,

there's a kind of lip in the ocean floor. So there's a very cold pool of Arctic water on one side. There's the North Atlantic on the other. And there's this kind of barrier between the two that's got a bit of a notch in it. And the cold, denser. water, which is dense because it's cold, sort of flows over the notch and then sinks, it goes like a waterfall under water, it goes down into the North Atlantic, and it slithers

along the bottom because it's dense water. And the thing about that is it's got to push other water out of the way. So you've got this kind of downward movement that's then flowing southward. And so density causes very, very slow movement in the deep ocean, much, much slower than at the surface. But the de potion is moving on its own timescale, almost separately to what the surface is doing a lot of the time. And so things that go down into that deep water can stay down for hundreds or thousands of years because that's moving very slowly. The surface is all moving around

much more quickly. But the places where they connect are incredibly important because that's when your quick, you know, your bit that's in contact with the ocean sort of becomes, it's like going down into the catacombs. And once it's down there, it's likely to stay there for a long time. And is it another myth or kind of how likely is it that the, you know, Arctic melt, the fresh cold water coming from melting glaciers, could kind of cut off the Gulf stream and send Europe into an ice age. So there's this idea that's been around for a while. So basically the idea here is that in order for that sinking process to happen, you need denser water. But if you're melting things, if you're melting ice nearby from Greenland,

for example, that's freshwater. And fresh water is not so dense. So then you're potentially mixing your dense salty water that might sink with fresher water that means it won't sink. And then you're potentially turning off this tap to the deep, which cuts off the surface ocean from the depths. And so that's, you know, there's this thing called the Atlantic meridial overturning circulation, AMOC. That's the name it gets called. And so there's a lot of discussion about whether freshening water in the Arctic will sort of turn that off. And it's a similar thing with the Gulf Stream, this thought that it might slow down. because of we're changing the density of water at the surface.

And, you know, the jury is still out on this. The latest, to my understanding, is that, you know, nobody thinks it's going to stop completely. That film, the day after tomorrow, whatever it was called, that is not going to happen. But even if these things slow down a little bit, they could have big consequences for what's going on underneath. I don't think anyone should worry about them stopping.

These are big engine components. They're not just going to turn off overnight. However, even if they slow, slow down, that might have an influence on deep ocean oxygen, for example. So it will still have consequences. But it's not this, you know, I think it's not this kind of dramatic tipping point, oh, it's going to switch off and we're all going to have nuclear winter. It's that it's much more insidious than that in some ways. And it's to do with, you know, where there's oxygen in the deep ocean for things to live and where the nutrients get to and whether anything that's in the

deep water can come back up to the surface again. But I think this, this idea that it's just going to turn off. I don't think anyone needs to worry about that. We've got plenty of other things to worry about that are bad enough before we get there. So the kind of nutrients being cycled round. Could you explain a little more about how the ocean's currents facilitate life? So there's this great paradox in the ocean, which is that the whole thing is powered by energy from sunlight. You know, there is a tiny amount of geothermal energy, heat-wise down below, chemical energy. It's minuscule. It's not really doing anything in the big picture at all. So the ocean is powered by sunlight. And sunlight carries energy, but water is really opaque to sunlight. Like,

we think of water as being transparent, but it really isn't. Light does not travel through it very far. And that means that what happens is that the light goes into the ocean at the top, and it can't really go anywhere before it's turned into heat. But that means if something wants to use light energy to photosynthesize, they have to be at the top, because that's the only place there's any light. But the other thing you need is the right atoms to kind of build stuff out of. You some matter, some material. And the thing about life in the ocean is that all these long carbon-based molecules that life are made. Anything that's alive basically is more dense than water. So lots of life, you know, lives and dies and it cycles around in the surface. But over time, there's this gradual

things tend to sink downwards. They're not going to tend to rise upwards. So you've got this slow leakage downwards. And so the sort of great paradox of ocean life, if you like, is that if you just let this system run, if you just let it carry on, the sunlight would all be at the top, the nutrients would all have sunk down below and nothing could happen. You're stuck. And there are some parts of the ocean where this is pretty much what happens. Like out in the middle of the North Pacific, for example, the water is really, really clear because there's nothing living in it, or very, very little living in it. And so you can see through it a long way, but that doesn't really help because the light energy still can't reach down to where the nutrients are. So it's kind of a desert.

But then there are places where deeper water can slither up to the surface. And these are known as regions of upwelling. There's a really famous one down the coast of Chile where the nutrients, the cold, nutrient-rich water can slither up to the surface and reach the sunlight. And then you've got everything. Then you've got everything you need for life. And so basically the distribution of life in the ocean is entirely based on where this paradox is broken. The places where nutrient-rich water break. through to come up to the surface and then you have both nutrients and light. And so it's not the case that there are just fish everywhere. It doesn't work like that. Just like on land, there are the equivalents of rainforests and deserts and places that are very productive and places where there's almost nothing. And that's all set by where the nutrients and where the light are. And it's quite incredible. I mean, you only have to tweak this a little bit one way or the other and you get a very different distribution of life. So we're as kind of in an happy sort of Goldilocks bit in the middle where just got the right amount

so that the ocean is interesting, but it's not all mixed up into a big pond. But it gives the structure. It's why there are such rich fishing grounds around Iceland. It's why the Humboldt current has this gigantic, 20% of the world's fish come just from this tiny region of the ocean. It's because that's where the paradox is broken. When you need to build up your team to handle the growing chaos at work,

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name audio creates systems that deliver exceptional sound and unforgettable listening experiences at home. Try it for yourself at a focal powered by name boutique. Visit focal powered by name.com for more information. A lot of us think of finding Nemo, I think, when we think of currents and the turtles kind of traveling across the world on these highways. How accurate is that? Turtles do travel around ocean gyres. I have to confess to not having watched Finding Nemo. I never got around to it at the time. And now I feel like everyone's going to be asking me about it. So I probably should watch it. But it is the case that sea turtles can, you know, so these big slow ocean gyres that kind of go around in circles, baby sea turtles, for example, they're not strong enough to swim exactly where they want to go.

But they can hitch a ride on those currents and get carried quite a long way. And then the adults have to swim back. So it is true that lots of animals actually get carried on those currents, especially when they're in their juvenile phases, when they're not big enough. So European eels are a good example that they born in the Sargasso Sea and they're tiny. They can't do anything, but they get carried by the Gulf Stream to Northern Europe and then they can live in European waters, European freshwaters. And then when they're grown to adulthood, you know, perhaps 10 or 20 years later, then they're strong enough to swim back without the help. of the currents. So it is absolutely true that currents carry things around. And that's how animals, one of the messages I think is that, you know, all this stuff, it's not just randomly positioned. It's not just, oh, there happened to be some turtles over there or there happens to be, you know, this kind of fish over there. They're there because there's a feature in the ocean engine that means that's a good place to live. And that's what shapes how their ecosystems work. And in your book, you talk about messengers and passengers and voyages. So all the different ways of kind of using and

travelling along these currents. Humans are obviously a great historical voyage of the sea and we've got a huge maritime history and a strong relationship to the sea. But could you tell us a bit more about the other creatures that use the sea in this way and depend on this movement for their life? Well actually, you know, especially in the UK, we think of ourselves as a maritime nation, but we don't even look at the sea. There's this phrase that the merchant marine use, which is sea blind, which is the ability to sort of talk around. the sea, but never actually look at it. And we are a very sea-blind nation, which is a bit weird for an island. But anyway, so messengers are things like light and sound that carry energy and

information through the ocean. The passengers are the passive citizens of the ocean, just get carried wherever the water takes them. The voyages are the ones that can navigate between these features in the ocean. And they're very specifically going from one feature to another. They're not just going out into the sea to go hunting. They know where they're going, because the ocean has a predictable structure. So, for example, there are penguins that live in the southern ocean on the little island, lots of islands actually, but, you know, Kurgland Island is one of them. And we all know what penguins do for David Attenborough shows, right? You know, there's a pair, a male, female pair who are bonded, they lay an egg, then they take turns looking after the

egg while the other one goes hunting. The thing about being a penguin is you're not very big, and you might be a good swimmer. You've only got a short period before you've got to come back. You've got to come back to let your mate take their term to feed. And so you've got to know where you're going. And so the penguins on one particular island that I write about in the book, they do know where they're going. They swim directly south for a week. And what they find is a big wall in the ocean. And it's kind of, it's like the boundary between two different types of water. And it's a place where there's loads of nutrients, there's lots of mixing. It's like a city. So it's like a city of the shape of a wall that stretches through the southern ocean. And that's where the penguins go. They go

straight there. They don't bother hunting until they get there. They get there and then they dive down and then they catch lots and lots and lots of fish because that's where all the fish are. They've effectively gone to the city to go foraging and then they feed there for a few days and then they swim for a week back to their chick or their egg. And the thing is they know it's there. They know that feature is there because the physics of the ocean has put it there, if you like. And so the ocean is full of features like that where anything that has the ability to swim can swim to the feature it needs and can feed and then can come home and it's predictable. That's the ocean at the moment until very recently has been a predictable place. So there's no way, they're not wasting energy,

they're not wasting time. They can immediately get what they need. And the story of the ocean's voyages, humans included, is full of examples like that. And one of the possibly not voyages, but passengers, I think, by your definitions, is the Janthina, Janthina species that you write about in the Blue Machine. So this is the sea snail that blows its own little bubble raft and floats without any control on the surface of the sea. But recently these were discovered in huge volumes in something called the Great Pacific Garbage Patch.

So this is a kind of huge island of plastic formed by those gyres that you were talking about before, the kind of swirling currents. Could you tell us a bit more about the garbage patch and how the ocean's currents gathered up our rubbish and kind of dumped it all in one place? So there's a couple of things here. So there is this picture of the garbage patch being like a floating rubbish tip of the sort we would understand. It's not like that. There are some very large pieces of ocean trash, which tend to be from fishing vessels. So they're tangled up fishing nets quite often if there's been illegal fishing and they think they've been seen.

They'll cut the nets and they'll drift around. So there's a small amount of very big stuff like that. And you can see that every so often. You'll see a big lump of that. But the rest of the Pacific garbage patches, very small pieces of plastic. And they tend to be up at the surface. When there's a storm, they get mixed down.

But we're talking about very small pieces because what happens is that it takes a long time for plastic to get from the land into the center of a gyre. And on the way, there's lots of UV in the sunlight. And mechanical, you know, being hit by way. and so it breaks down into small pieces. So actually in those regions of the ocean, if you scoop up a pot of water, you might not see anything. But within it, there are tiny, tiny pieces of plastic, which are problematic because they look like food. And very little in the ocean has a sense of taste, because if it's organic, you can probably eat it. So they just eat whatever

lumpy things they find, basically. So you asked why it accumulates that. Well, it's because of that thing about as the gyre, you know, as the gyre rotates, water gets pushed in towards the middle because in the northern hemisphere, if a current's going straight, it will get pushed to the right. So things on the surface get pushed in towards the centre. Now underneath them, the water is sinking down a little bit, but anything that floats is just going to float at the surface. It's got nowhere to go. So it will drift into the centre of the gyre and then there's no way for it to get out unless it goes down. And so that's why things tend to accumulate in that area. And so, you know, there's something to be very clear about here, which is that apart from the large pieces of fishing gear,

clearing that up is not an option. And the reason it's not an option is because those tiny pieces of plastic are exactly the same size as ocean life. So if you filter them out, you take out the tiny zooplankton, the things that are, the gels, the very fragile structures

that are living in the ocean, we can't vacuum the ocean. So the message of the ocean garbage patch is that what we have to do is stop putting it in. We can take out the big pieces of fishing gear, although actually you tend to find that they've got their own ecosystems

attached to them, things are using them as shelter, things are using them as a substrate to live on. Things like the snails then come along. You know, there's actually, we're finding that there's life sitting on top of the plastics because, you know, if there's a place to live, life will have a go. But it does cause damage mainly because organisms eat it, thinking that it's food. And then they have a full stomach and they're getting no nutrition. And that's a very significant problem.

But the solution is to stop putting it in. There is no way, those tiny, tiny pieces of plastic, we are. There's no way to clean those out without completely destroying the living fabric of the ocean. And another human impact on the ocean is from shipping, but also from shipwrecks. And there's that relationship between, well, as you say, these structures that then become kind of ecosystems on their own. But you also write really interestingly about how the Titanic was found. So could you tell us a bit about the relationship between wrecks and oceanography? Ricks are obviously interesting historically, they don't always last very long. So, you know, everyone thought the Titanic would be

in great condition when it was found, because it was sitting at the bottom of a cold, deep ocean, there probably wasn't much life around, they thought, they thought it would just sit there. Actually, it turns out there's loads of stuff there, and it's not just that, you know, the creatures have eaten all the leather armchairs and things, the things that are obviously organic, but there's enough oxygen to rust away the ship. So the Titanic is probably not going to last much longer, you know, maybe another 60 or 70 years, and then it's just going to rust away into the ocean. So the way we find wrecks, obviously wrecks are caused generally by things the ocean has done. We are land mammals, we need help to go to sea, we need these kind of shells, these little life

support systems. That's what a ship is. It's a life support system to take you into an alien environment. And it's physics that determines where they end up. So in the case of the Titanic, for example, what allowed them to find the Titanic was that when the ship broke in half, which it did, people were skeptical about that, and then they found the two halves. People didn't believe the survivors, basically, who said it had broken in half. But they didn't find the ship. What they found was the debris, because as we were talking about before, you know, as on the surface, a floating thing could float to lots of different places.

You know, you put two things in next to each other, they'll end up in lots of places. Well, when you sink downwards, the speed of sinking downwards depends on the size. So smaller things sink more slowly, and the smaller things also get moved around by the currents more. And so actually, there's a sort of a square kilometer around the wreck of the Titanic, which is full of these things that have been distributed by the currents. The physics took them to lots of different places. But what that meant is that when Bob Ballard, on the Knorr, actually, which I was on, I wrote about later in the book, when they went looking for the Titanic, they didn't, they realized that looking for the ship was the wrong thing to do. So the physics of the ocean both caused the wreck in the

first place, but also dictated how it was all distributed and was what allowed them to find it. Recent technology have been able to map the wreck of the Titanic and these amazing 3D scans. So I just wanted to finish up by asking whether there are any really exciting pieces of tech or exciting new ocean discoveries that you're looking forward to us knowing more about, not necessarily in wrecks but in the ocean generally. Well, there's lots of things, but I'll pick one, and that is that in the northeast Pacific, there is an underwater sort of surveillance system for a series of underwater volcanoes. And we have, even though we know, and the evidence is very, very solid on this,

that the way the ocean crust forms is that two pieces of crust move apart of volcanoes in the middle, basically spew out lava and it fills in the gap. We know it happens, but we've never been there when it happens. Now there is a project in the Northeast Pacific, basically, you know, and it's kind of like it really is a surveillance system. It's got cameras, it's got lots of measuring devices. You know, they sample things. It's kind of sending data home in real time.

At some point, that volcano is going to erupt. And this time we'll actually see it. And I think that, you know, one of the things that they already know from the start of this system is that actually things in the deep ocean can change very quickly. They tend to change very slowly, you know, things accumulate slowly. They erode slowly. But actually when you get these big explosions, underwater explosions, everything changes very quickly. And so being able to watch that happen will be a very dramatic moment.

And I'm very much looking forward to that. That was the physicist Helen Chersky, whose new book, Blue Machine, about how the ocean shapes our world, comes out later this week. Thank you for listening to this episode of Instant Genius, brought to you by the team behind BBC Science Focus magazine. The current issue of BBC Science Focus is out now. Get your copy in supermarkets, newsagents, or wherever you buy your favourite magazines. You can also download a digital version via our app and visit us online at sciencefocus.com. This podcast is sponsored by Name, Audio and Focal. The texture and emotional depth of music can be lost through digital sources or poor signal.

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