Sticky Science: The Force Be With You with Laurie Winkless

What are Van der Waals forces? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly explore the fascinating world of surfaces, biomimicry, and Formula 1 with physicist and author of Sticky: The Science of Surfaces, Laurie Winkless.

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

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. This is Sports Edition. And I got with me my co-host, one of two for this format, Chuck Nice. Chuck, how you doing, man?

• 0:27Chuck Nice?

  Hey, man. Yeah, Sports Edition. I'm the guy who, in whatever iteration of sports, I'm the guy bringing the water.

• 0:34Neil deGrasse Tyson?

  Is that what you do? Gatorade?

• 0:37Chuck Nice?

  I'm the Gatorade guy. That's me. Hey, how you doing? You thirsty? You thirsty? You need some electrolytes there, buddy?

• 0:45Neil deGrasse Tyson?

  It's gonna squirt it into your mouth?

• 0:47Chuck Nice?

  Yeah, exactly.

• 0:50Neil deGrasse Tyson?

  All right, we got Gary O'Reilly. Gary from the UK. You're with the Stateside now, I think, but you're

• 0:58Gary O'Reilly?

  I am, yes.

• 0:59Neil deGrasse Tyson?

  Recently in the UK. Played professional soccer there. For professional football, I guess they call it. And you were an announcer there. So we are delighted to have both of those features within you for this. So Gary, just tell me what you got up your sleeve for today.

• 1:15Gary O'Reilly?

  Um, something we take for granted, Neil. Imagine surfaces. We engage with so many everyday smartphones, our clothing, footwear, kitchens, even paint. But what is happening at a molecular level?

• 1:31Chuck Nice?

  Oh, they're all disgusting. That's what's happening at a molecular level. They're all nasty.

• 1:36Gary O'Reilly?

  All right, well, we'll see if that's the case. I mean, is it material science? Is it physics?

• 1:41Neil deGrasse Tyson?

  Chuck, I didn't know you had such strong opinions about molecules. This is, this

• 1:45Chuck Nice?

  I do. Especially when they form bonds that actually hurt.

• 1:49Neil deGrasse Tyson?

  Oh, got it. Molecular bonds. Okay. Go on, Gary. We interrupted you.

• 1:54Gary O'Reilly?

  All right, so, I mean, and then we'll get to the friction, which happens when certain surfaces connect. And then we have biomimicked so much from Mother Nature and tried to recreate her work. And we've even taken these inventions into space. So we'll go there as well. But really, right now, what we need is someone who could Make paint drying seem interesting. And I think what we have is just the person. So Neil, if you would like to introduce our guest today, then we'll go from there.

• 2:26Neil deGrasse Tyson?

  I'd be happy to. So we've got Laurie Winkless. Laurie, did I pronounce that correctly?

• 2:31Speaker 03

  Perfectly, Neil. Yeah, well done.

• 2:33Neil deGrasse Tyson?

  Excellent. You're coming to us with an Irish accent, but at the moment you're in New Zealand.

• 2:40Speaker 03

  I am.

• 2:40Neil deGrasse Tyson?

  Very cool. Thank you. Thank you for hanging with us, even though you're on the other side of the earth at some unholy time of day in this interview, because it's a regular time of day for us.

• 2:51Speaker 03

  Oh, it's all good. It's almost 9 a.m. It's all good.

• 2:55Neil deGrasse Tyson?

  Oh, that's okay. Okay, 9 a.m. tomorrow.

• 2:58Speaker 03

  Yeah, tomorrow, in the future.

• 2:59Neil deGrasse Tyson?

  For us.

• 2:59Gary O'Reilly?

  She's from the future. She's from the future.

• 3:03Chuck Nice?

  You're rather sprite to be coming to us from the future.

• 3:06Speaker 03

  It's much better here.

• 3:10Neil deGrasse Tyson?

  Early morning tomorrow. You have a background in physics and in space and in working in national labs. You're a science communicator, a lecturer. I love it all. You've got books. One of them is called, was it Science and the City?

• 3:26Speaker 03

  Yeah, that was my first book.

• 3:28Neil deGrasse Tyson?

  I love it. Wonderful title. And most recently, what's called Sticky, The Secret Science of Surfaces. And that sounds all about friction. We've done several shows talking about friction in sports. So this will fit right into that, to that portfolio. So, so let me, let me just sort of start off. I think I'd start a question I got for you. So I think people want to know about gecko feet.

• 3:57Chuck Nice?

  By the way, isn't that gecko from New Zealand?

• 4:00Speaker 03

  There is a gecko in New Zealand, and it's a very unusual one because it lives in the mountains. It's an alpine gecko.

• 4:06Chuck Nice?

  No, I was talking about the Geico gecko.

• 4:10Gary O'Reilly?

  Oh no, not him.

• 4:11Neil deGrasse Tyson?

  What accent does the gecko gecko have?

• 4:13Chuck Nice?

  What accent does the gecko gecko have?

• 4:14Gary O'Reilly?

  He's in East London. You'll know this Laurie, there's a soap opera in England called EastEnders. It's based in the east end of London.

• 4:22Neil deGrasse Tyson?

  We have it here.

• 4:23Gary O'Reilly?

  Yep, he is one of the cast members.

• 4:25Speaker 03

  Oh.

• 4:26Chuck Nice?

  Oh.

• 4:26Gary O'Reilly?

  And he's not putting on a voice. That's him.

• 4:29Chuck Nice?

  That's him. That's just him.

• 4:31Gary O'Reilly?

  Although he's not green.

• 4:32Neil deGrasse Tyson?

  The gecko isn't the actor who is that voice is a cast member.

• 4:36Gary O'Reilly?

  Yes, not the gecko.

• 4:37Neil deGrasse Tyson?

  I'm sorry. Because the last time I saw EastEnders, I don't remember talking animals.

• 4:41Chuck Nice?

  I don't remember the gecko.

• 4:42Speaker 03

  Talking gecko would make it a lot more interesting.

• 4:44Gary O'Reilly?

  All right Laurie, let's unravel the gecko. So if I've got this right, you've got hairs on hairs on scales on toes on feet.

• 4:52Speaker 03

  Yeah, that's pretty much it actually Gary. Yeah, the gecko foot is what we call a hierarchical structure. So what that really means is that it has features of different sizes that combine together to give the gecko its climbing superpower, I suppose. So if you look at a little gecko's toes, usually the toes themselves are pretty strong. So that's often enough to get them to cling on to like a bark of a tree or whatever.

• 5:17Neil deGrasse Tyson?

  Just to be clear Laurie, I've never done this. You said if you look at a gecko's toes.

• 5:21Speaker 03

  You've never looked at a gecko's toes?

• 5:23Neil deGrasse Tyson?

  I'm sorry.

• 5:24Chuck Nice?

  Yeah, I understand that there's a fetish site where you can do it.

• 5:29Gary O'Reilly?

  Oh no. I really hope not.

• 5:31Speaker 03

  Okay, so I'll take a step back. Geckos usually have four legs. I'll start there. They're little lizards. And they have, depending on their species, like four or five toes on each foot. Okay? So the thing about their toes is, and sometimes if you see them at maybe a zoo or something, if you see them on a glass surface, that's usually the best way to get a real like insight into what's going on. So you've got their little feet. On their toes, their toes are covered in these flaps of skin and they're called lamelle. They're just stripes of skin. And for the longest time, scientists, you know, we just thought that that was, it was to do with those flaps of skin. Like maybe they were acting as some sort of like a suction cup or maybe.

• 6:12Chuck Nice?

  They look like a pad.

• 6:13Speaker 03

  Yeah, exactly.

• 6:14Chuck Nice?

  When they're pressed against a flat surface, they look kind of like a pad.

• 6:18Speaker 03

  Yeah, they flatten out. So like that was what we thought, that was all we thought the geckos could do. But like as microscopes began to develop more and get better and better and we could zoom in a bit further. Like Gary said, we realized those flaps of skin are actually covered in this very, very dense forest of hairs. And they're called sitae. So they're just hairs, but they increase the surface area so much. So it's now not a flat bit of skin. It's a really heavily textured forest of hairs. If you zoom in on the end of each of those hairs, you'll find that they actually, they each have like a really bad case of split ends, right? So each one of those hairs splays

• 6:57Speaker 03

  out into lots of other smaller hairs. And the ends of those hairs can make such intimate contact with surfaces. Now, when I mean intimate contact, I mean getting within one nanometer of the molecules that make up the surface.

• 7:14Neil deGrasse Tyson?

  Oh.

• 7:15Speaker 03

  Yeah.

• 7:16Neil deGrasse Tyson?

  So what you're saying is the surfaces we might think are smooth, but on the, on the very small level, they're not.

• 7:20Speaker 03

  Yeah.

• 7:21Neil deGrasse Tyson?

  And so if you have something small enough.

• 7:23Speaker 03

  Yep.

• 7:24Neil deGrasse Tyson?

  To get in the nooks and the crannies, especially the crannies.

• 7:26Speaker 03

  Yeah.

• 7:27Neil deGrasse Tyson?

  Then I don't know the difference between a nook and a cranny. Chuck, you have any insight into that?

• 7:31Chuck Nice?

  Yeah. The nooks are not as delicious.

• 7:35Neil deGrasse Tyson?

  As the crannies. Okay.

• 7:37Speaker 03

  But yeah, everything is rough. So what you really want to do is you want to increase the contact points as much as possible if you want to get to, to get to touch the surface as much as possible. So like when you will see geckos and if you see them in the wild, they can climb on everything. You know, they're running across waxy leaves and wet rocks. They can climb on glass. They can be inverted on sheets of glass, which are a material, it's a material we think of as really smooth. But yeah, as Neil said, on the micro scale, it's not smooth. It's very rough and textured. So these tiny hairs can kind of get in there and they can start, it's, it's a force called van der Waals interaction. It's a force that

• 8:18Speaker 03

  you can only tap into when atoms are close enough together. And that is what the gecko uses. Like the gecko's foot is effectively feeling for electrons in the atoms of whatever the surfaces that they're climbing on.

• 8:34Chuck Nice?

  What, what, what you're kind of describing on an atomic level is Velcro.

• 8:38Speaker 03

  Yeah. Yeah. To be honest, it's very similar.

• 8:40Chuck Nice?

  Yeah. It's, it's, it's basically like. It's electric, electric Velcro. It's molecular Velcro with, with electrons and, and, and looking for a signal rather than just, you know.

• 8:52Neil deGrasse Tyson?

  Clasping together and pulling apart.

• 8:53Speaker 03

  Yeah, and the thing that's even more impressive about the Gecko's version of this Velcro is that it can detach really quickly. So you know when you're pulling Gecko or pulling Gecko's apart, don't do that.

• 9:04Neil deGrasse Tyson?

  Yes, yeah.

• 9:05Speaker 03

  When you're pulling.

• 9:05Neil deGrasse Tyson?

  That's my favorite, it's my favorite pastime, by the way, Laurie.

• 9:08Speaker 03

  When you're pulling Velcro apart, you get that like really loud noise and it takes quite a lot of force. But a Gecko, all a Gecko needs to do is it curls its toes back and that changes the angle that those split ends, those hairs are making with the, with the surface and that turns off its stickiness instantly. So Gecko's can turn on and off their stickiness depending on the orientation of their toes. And that's why.

• 9:34Neil deGrasse Tyson?

  Otherwise, they wouldn't be able to actually walk.

• 9:36Speaker 03

  Exactly.

• 9:36Neil deGrasse Tyson?

  You know, you, you place them down or they just get stuck there forever.

• 9:40Speaker 03

  Yeah, being ultra sticky isn't that useful, to be honest. Like you want to be able to turn it on when you need it and turn it off when you want to scarper. So yeah, the Gecko like has all of these features that are all working together to get that contact at the atomic level, at the, you know, really talking about electrons to, in order to climb. Yeah, they're amazing, little lizards.

• 10:00Chuck Nice?

  Amazing.

• 10:01Gary O'Reilly?

  Am I right here, am I right here, Laurie, where you get a Gecko that may be a half a pound or a pound in weight, right? And you stick it to the ceiling and then it can hold nearly 300 pounds of weight.

• 10:16Speaker 03

  Yeah, in theory.

• 10:17Gary O'Reilly?

  A, how? A, the question is broke down into two parts. A, how? And B, how on earth do you test that it can hold that much weight without being crawled to a Gecko?

• 10:28Neil deGrasse Tyson?

  Unfortunately, there's a few Gecko's who gave their life for that experiment.

• 10:31Speaker 03

  Yeah, yeah. To be honest, if you look back at the early history of Gecko research, there really are a lot of Gecko's that were treated badly. But in terms of this research, it's really based on a measurement taken on a single one of those hairs and then they scale it up to, yeah, I mean, so it's kind of, that's why I say in theory, right? There's this kind of a scaling question. Because, you know, really a Gecko shouldn't ever need to, you know, be able to support that sort of force. But why it's so good is because it's not usually in a lab, right? Like I said, it's usually running around in the forest.

• 11:08Neil deGrasse Tyson?

  I don't want the Geico company to learn about this because they'll make TV commercials where that little Geico Gecko is saving people.

• 11:16Speaker 03

  Yeah. Oh, no, we don't want that.

• 11:18Neil deGrasse Tyson?

  Right, right, right, right.

• 11:19Chuck Nice?

  Actually, Neil, that's kind of cool.

• 11:22Chuck Nice?

  So wait, before we, uh, cause I know we're gonna get off of geckos in a minute, but I'm just fascinated because we're talking about sticky, so I know we gotta leave the gecko. However, when you look at the design of their anatomy, is that also to disperse their weight?

• 11:38Speaker 03

  Yep.

• 11:39Chuck Nice?

  So that they can do these things you're talking about?

• 11:41Speaker 03

  Yeah, what a good question.

• 11:43Chuck Nice?

  They're like, super stretched out.

• 11:45Speaker 03

  Yeah.

• 11:45Chuck Nice?

  With a tiny little skinny body.

• 11:47Speaker 03

  Totally. They absolutely do. The whole animal has a role to play. It's not just its toes. Um, like for a start, they kind of do jazz hands when they're, when they're trying to get, they try to balance out the forces as much as possible. So a gecko-

• 12:00Neil deGrasse Tyson?

  For the non dancers out there, jazz hands are fully open, palm forward, all fingers spread.

• 12:06Speaker 03

  Indeed.

• 12:07Neil deGrasse Tyson?

  It's showtime, folks.

• 12:08Speaker 03

  Showtime, yes. Well, yeah, on the ceiling, they'll do that so that their toes are pointing in opposite directions so that the forces are all spread out evenly across all of their toes. And a gecko can very easily just cling with, with the single toe. Um, they don't need all of their toes to be perfectly engaged in order to be able to climb. Yeah, they're amazing.

• 12:27Gary O'Reilly?

  That's just showing off. So, okay, so now, once, once we, because it's taken us basically till the 21st century to really get a grip on understanding what's keeping a gecko glued to a wall or a ceiling.

• 12:38Neil deGrasse Tyson?

  I see what you did there, Gary. So get a grip on this. Yeah.

• 12:41Gary O'Reilly?

  Uh huh. Thank you.

• 12:42Neil deGrasse Tyson?

  I see what you did there.

• 12:43Gary O'Reilly?

  And I know, these things aren't just thrown together.

• 12:48Gary O'Reilly?

  We've mimicked that. And we, we came up, we being very smart people, not me, came up with gecko tape. And we have actually gone into space with things based on a gecko's feet.

• 13:01Chuck Nice?

  Are these real things? What's gecko tape?

• 13:03Speaker 03

  Yeah. So gecko-

• 13:05Gary O'Reilly?

  Lolly?

• 13:06Speaker 03

  Gecko tape, it kind of came out of a lab at Stanford. And, um, what they've done is they, they know that it's, it's not possible. We, we do not have the ability to recreate the level of complex structure that a gecko has naturally evolved on its toes. But what they can do is they can kind of take some of the essential elements and kind of cheat a little bit, copy a little, copy some of that. Um, and what it looks like really, and I got to play with some myself when I visited, it's this, it's a silicone rubber, so a very flexible gray rubber. And if you look at it, it just looks quite rough. But if you look at it under a microscope, it's actually covered in tiny little wedges. So it's been patterned with these wedges that are angled. And they're at a similar angle to the sitte, these hairs on a gecko's foot.

• 13:50Speaker 03

  So what they do is you can apply that, if you have that on, say, like a robotic arm for something, you can bring that robotic arm up against, say, a solar panel if you're on the International Space Station. And you put the gecko tape up against whatever it is you're trying to pick up. And you tug it down slightly, there's just a little button on the, on the system. That's, that causes those wedges to splay out. So again, kind of tapping into the same idea as the hairs, although much, much larger than hairs. They, they're not quite as, they don't make quite such intimate contact. But because the gecko's so special, it doesn't need to make quite such intimate contact. It can make a little bit of it and it does, it does enough.

• 14:30Speaker 03

  So, um, you can do that without using like a suction cup, which is usually how we move big awkward things around. You can do it without using any electricity. There's a lot of grippers that we use, use electricity, electrostatics to pick stuff up. And they don't have any clamping forces. You can actually pick up very delicate things just by putting this gecko tape, the silicone rubber, onto the surface and causing its wedges to kind of splay out and move it around.

• 14:58Neil deGrasse Tyson?

  Forgive me, but the first thing I thought of when you were describing this tape is a new arcade machine where you wanna get the toy inside the thing. You just, because you can never get it, right? You can never get the toy. With the clamp, we get some of your tape, we win.

• 15:14Speaker 03

  Every time, every time, yeah.

• 15:16Neil deGrasse Tyson?

  Oh, yeah. The toys are coming home with me. Okay. This is amazing. Yeah. So this is actually used in space now?

• 15:24Speaker 03

  Yeah. So it was, it was trialed initially on the vomit comet. And then it eventually went up on the International Space Station. I think it's had several trials now on the International Space Station to be used as a, as a low-gravity gripper manipulator. And it's already-

• 15:38Neil deGrasse Tyson?

  Could you please tell the one in a hundred of our listeners, because that's all it will be, what the vomit comet is?

• 15:43Speaker 03

  Oh, yeah. So the vomit comet is one of NASA's test facilities. It's a plane, basically, that flies in a parabolic- Um, path and it simulates well, low gravity for short periods of time. So if you want to test something out in low gravity, that's a good way to do it. So they've been.

• 15:59Neil deGrasse Tyson?

  Or even zero.

• 16:00Speaker 03

  Or zero gravity. Yeah, indeed.

• 16:01Neil deGrasse Tyson?

  Yeah, yeah.

• 16:02Speaker 03

  If only I'd love to have a go in the vomit comet if anyone's listening. Um, but yeah, so it's.

• 16:07Neil deGrasse Tyson?

  I'll put in a good word for you.

• 16:08Speaker 03

  Thanks Neil.

• 16:09Neil deGrasse Tyson?

  With Dramamine.

• 16:11Speaker 03

  Well, yeah, so it is, it is being used and it's actually already being developed and used in on factories on earth as well. So they're, they've commercialized some of these grippers to be used in, in robotic systems to, to pick up awkwardly shaped objects.

• 16:23Chuck Nice?

  Yeah.

• 16:24Gary O'Reilly?

  Wow.

• 16:25Speaker 03

  It's pretty cool.

• 16:26Chuck Nice?

  That's more than cool.

• 16:27Neil deGrasse Tyson?

  So tell me about, so tell me about the, uh, what happens if water is between your thing and the surface?

• 16:35Speaker 03

  Yeah.

• 16:35Neil deGrasse Tyson?

  Usually because, because water is like the enemy of tape.

• 16:38Speaker 03

  Yeah.

• 16:39Neil deGrasse Tyson?

  Right?

• 16:39Chuck Nice?

  Yes.

• 16:39Neil deGrasse Tyson?

  If you get tape wet, nothing sticks anyway, no how.

• 16:42Speaker 03

  Yeah.

• 16:42Neil deGrasse Tyson?

  So what goes on there?

• 16:44Chuck Nice?

  Uh, except for Flex Seal Tape, I have to tell you, I've seen those.

• 16:47Speaker 03

  Good stuff.

• 16:50Speaker 03

  Yeah.

• 16:50Chuck Nice?

  Sorry.

• 16:50Speaker 03

  Water, no, water is a problem. You're right, Neil. Um, the Gecko has evolved to, to cope with it because its feet, as well as being amazing for gripping, they're also hydrophobic. So those feet actively repel water. They push water out of the way so that they could make dry, effectively dry contact with whatever surface it's touching. Um, for the silicone tape, again, silicone itself is hydrophobic, so it tries to repel water as much as possible. It's not perfect, but it works well in also.

• 17:19Chuck Nice?

  So let me ask you this, is there any way to take this type of technology and apply it to tires? Because I could see so many applications for, for a safety. As a matter of fact, there was a show called Speed Racer when I was a kid and one of them.

• 17:34Neil deGrasse Tyson?

  I remember Speed Racer.

• 17:35Chuck Nice?

  You remember Speed Racer? So Speed Racer had.

• 17:37Gary O'Reilly?

  You're gonna sing again, aren't you? You're gonna sing. The pair of you are going to sing.

• 17:40Chuck Nice?

  Oh my God. Make me, don't.

• 17:42Neil deGrasse Tyson?

  Here comes Speed Racer. He's a demon on wheels.

• 17:46Chuck Nice?

  Okay, okay. Anyway, one of the things were these super sticky tires that would allow the car to ride on any surface and even stick to the walls. And of course that can't happen, but.

• 17:57Neil deGrasse Tyson?

  Or to not lose traction.

• 17:58Chuck Nice?

  Or not to lose traction on a wet track.

• 18:00Neil deGrasse Tyson?

  They actually stop NASCAR when it rains.

• 18:03Speaker 03

  Yeah.

• 18:04Neil deGrasse Tyson?

  And if you and you've got this. All right, but we're gonna do tires in the next. Okay, well, oh, okay. Well, let's just do that way. Let's just do that. Hold on to that. But put a pin in that. And Laurie, you can hang out. We got two more segments with you. And this is just amazing. I mean, I, I, I want to do the whole thing on geckos. I do, too. We got a lot of. See?

• 18:25Chuck Nice?

  Totally.

• 18:26Neil deGrasse Tyson?

  Who knew? I have never. I have never been so into geckos in my entire. Me neither. Me neither. It's like, oh, damn. And they come in different colors and different sizes.

• 18:37Chuck Nice?

  They are adorable. They are wonderful little ad lizards.

• 18:39Neil deGrasse Tyson?

  Damn, okay. When we come back, more StarTalk Sports Edition with surface expert Laurie Winkless.

• 18:58Neil deGrasse Tyson?

  We're back, StarTalk Sports Edition. We spent an entire segment talking about gecko toes. But as, as, as interesting as that is to a naturalist, this is sports edition, damn it. And I want to know, how are we gonna put gecko feet on rubber? For cars and stuff, car races. Can we go there, Gary? Is that someplace you can take me? We can go anywhere we want. We've got gecko feet and wheels. Let's lay down the rubber on that. We got Laurie Winkless, who's an expert on gecko feet. Laurie, is that on your business card?

• 19:38Chuck Nice?

  No, definitely not.

• 19:40Neil deGrasse Tyson?

  What do you carry around on your business? Oh, my God. But anyway, I'm delighted you're coming to us from New Zealand. A beautiful countryside. I'm not the first nor the last to say that. And thank you for coming on the line with us here across the ocean.

• 19:55Chuck Nice?

  My pleasure.

• 19:55Neil deGrasse Tyson?

  In North America. Yeah, so, so Gary, take, take it over. All right, so here's something that may or may not be in people's thinking.

• 20:05Gary O'Reilly?

  But it's a Wiki fact. Tribology, I'd never heard of it before, but it is the science and engineering of interacting surfaces in relative motion. It includes the study and application of the principles of friction. Now, I hadn't thought of that as a science, but tribology is what we have.

• 20:25Neil deGrasse Tyson?

  Why don't they call it frictionology or something? Why they gotta be obscure about it?

• 20:29Gary O'Reilly?

  Yeah. Because the ancient Greeks got there first and they've decided it's tribology.

• 20:34Chuck Nice?

  All right. Slickology would be better.

• 20:37Gary O'Reilly?

  There you go.

• 20:39Chuck Nice?

  Yeah. So have you ever heard of that, Laurie?

• 20:40Speaker 03

  Yeah, yeah. So a lot of the, a lot of this book is about tribology. And the short version is like, it's the science of rubbing and scrubbing. That's how it's often described.

• 20:49Chuck Nice?

  I love it.

• 20:50Speaker 03

  Which I love. Yeah.

• 20:52Chuck Nice?

  I gotta tell you, that sounded a little sexual there, Laurie.

• 20:55Speaker 03

  Yeah, well, I mean, there's an entire chapter on lubrication as well, Chuck. So, yeah.

• 20:58Chuck Nice?

  Oh.

• 20:58Speaker 03

  Plenty of opportunity for innuendo.

• 21:01Chuck Nice?

  All right. All right. None of this is making the show. All right.

• 21:06Neil deGrasse Tyson?

  What we've known and we've, and we've had shows on this very topic is that professional auto racing often, in fact, I might say all the time, leads automotive technologies with innovations that ultimately filter their way back to commercial vehicles. And, but we look at the tires, as far as it, you know, I see all the rest of the technology, they're still using rubber tires on the track. Is that, am I missing something there? What's either NASCAR or especially Formula One where the full rubber tire is sticking out all, all bare?

• 21:42Speaker 03

  Yeah.

• 21:42Neil deGrasse Tyson?

  What, what's, what's?

• 21:43Chuck Nice?

  When are we getting Gecko, when are we getting Gecko feet on our Formula One cars? And listen, if you think about it, when you look at racing slicks, okay, they're, they're kind of a, they've got to be a significant weight factor to the car. You know, so maybe that's something if you want to lighten the load, Gecko feet tires would be a great way to do it.

• 22:05Speaker 03

  Yeah, I mean, it's a funny one. The main problem with Echo Tape is that it's not very robust. So it's not actually very good. It wouldn't be very good under the weight of like a Formula One car or even just the Formula One tire, like you said. But I should say that they use rubber because it also, if it's designed well enough and if the track is smooth enough, it also can tap into those same forces, the van der Waals forces. Because like those big Formula One slick tires, they can make a similar intimate contact with a racetrack that a Gecko can make with a wall. Like racetracks are-

• 22:41Chuck Nice?

  It's because they're soft at some levels, right? I mean, that's why they're called rubber, right? I mean, they're, they fill in the, any little microscopic gaps.

• 22:50Speaker 03

  Yeah, exactly. Like tire-

• 22:51Chuck Nice?

  What's up, baby? This is your, this is your tire. How you doing? Just trying to make a little intimate contact with-

• 23:02Chuck Nice?

  You know? Just going one after hour.

• 23:05Gary O'Reilly?

  Sorry, Laurie.

• 23:10Gary O'Reilly?

  But so Laurie, so when you've got a Formula One race car and I mean, people like Lewis Hamilton will hammer the pedal down and this thing's gone over 200 miles per hour. Plus with a Formula One racetrack, you've got all sorts of curves, bends. I mean, a tire will go through all of these different forces, then a deformation, all the rest of it. How are you ensuring that it's still able to tap into those van der Waals forces under all these distresses?

• 23:37Speaker 03

  Yeah, really good question. The main, the main, there's two main ways that a tire makes contact with the road. And one of them is the way that normal tires make contact with the road, which is kind of what Neil said. It's about the rubber. Rubber is this material called, it's a viscoelastic material. So it's something a bit like a very viscous or sticky fluid and an elastic solid. So it's kind of sits somewhere in that range. And what it means is that tire rubber flows into all of those bumps and crevices and all of the, you know, roughness on a racetrack. And as it flows, it makes a kind of a frictional interaction. And that is mostly how tyres work, mostly how like road tyres will grip to the road.

• 24:19Speaker 03

  But Formula One tyres are usually flat, very, very particular compounds of rubber, like particularly their stickiness, their viscosity has been very well defined. And they're huge, right, this massive surface area that makes contact with the track. The track is usually also very smooth, so it can also tap into that van der Waals interaction, assuming the rubber can can actually just flow properly into the track. Now, sometimes you'll see a Formula One driver, and they talk about this, they talk about this in other motorsport too, about laying down some rubber, right? This idea of actually like the tyre degrading intentionally. Formula One is totally based on that. Those tyres are designed to degrade.

• 25:04Speaker 03

  They're designed to leave tiny, thin layers of rubber on the track. Because that increases the grip for the next time you go around the track. You lay down the rubber to increase the friction between your tyre the next time you pass by. But like on a normal car, you do not want your rubber to be degrading over the course of a few kilometres, right?

• 25:26Neil deGrasse Tyson?

  Yeah, because they change their wheels in an F1, you know.

• 25:28Speaker 03

  Exactly. And Formula One tyres, like the cost, I can't even, I don't even know how much it would cost.

• 25:34Neil deGrasse Tyson?

  Yeah, you don't want to have to change your wheels on the way to, you know, to the 7-Eleven, you know.

• 25:38Speaker 03

  No, no. Yes.

• 25:41Gary O'Reilly?

  You know what, Chuck, you know, when you're talking about you want Gecko tyres, right? Gecko feet on a tyre. Have they, Larry, done exactly that? Because a Formula One race will take place in the rain. And they'll obviously then have a tread pattern on the tyre. Which then discharges an awful lot of surface water. So are they using a similar sort of technique? That a Gecko would for being.

• 26:06Neil deGrasse Tyson?

  Wait Gary, do they swap out the tyres when it rains?

• 26:08Speaker 03

  Yeah.

• 26:09Chuck Nice?

  Yes, they do.

• 26:09Neil deGrasse Tyson?

  Okay, got it.

• 26:10Chuck Nice?

  It's a different, it's a different tyre with a normally with a channel through the middle of the tyre. And then some kind of, some, some type of channeling that moves the water away.

• 26:20Speaker 03

  Exactly, yeah.

• 26:21Gary O'Reilly?

  Neil, they'll, they'll have a whole team to manage, to, to manage the tyre, to manage the setup of the car based on the weather. It could be humidity, temperature.

• 26:30Neil deGrasse Tyson?

  I think they should have it also in snow, just to.

• 26:32Speaker 03

  Yeah, well, if you watch, like, if you watch rally, if you watch rally, they're, they're racing on ice, which is just crazy, but.

• 26:41Gary O'Reilly?

  I know, but they don't have tyre changes, do they?

• 26:43Speaker 03

  Exactly, in rallycross, you're right.

• 26:44Gary O'Reilly?

  No, but in Formula One you can.

• 26:45Speaker 03

  You have the luxury of that.

• 26:46Gary O'Reilly?

  Are they able to push that super hydrophobic sort of setup?

• 26:51Speaker 03

  The rubber itself is a bit hydrophobic, it is, it does repel water, but really it's the design of those tread patterns that pushes the water out of the way. So like a Formula One, I think it's the 2020 Formula One tyres, I need to check, but they remove, they can remove about 65 litres of water per second when the car is moving at full speed. Like the, every single pattern on a tread has been designed to suck the water up and like Chuck said, kind of push it out the sides of the tyre so that the contact is as dry as they can possibly get it. Like there's a limit, right? There's a limit as to how much.

• 27:25Chuck Nice?

  And so the tyre is basically a windshield wiper for the road.

• 27:28Speaker 03

  Yeah, exactly, a very expensive windshield wiper.

• 27:32Chuck Nice?

  A very expensive windshield wiper. So my, my question then is from a material standpoint, why not just do two things? One, increase the friction of the surface upon which you're driving. And two, make it so that the tyre becomes more interactive with that frictioned surface or that's, that, that surface that has more friction.

• 27:57Neil deGrasse Tyson?

  So Laurie, let me tighten up. Chuck's question?

• 28:00Chuck Nice?

  Please.

• 28:01Neil deGrasse Tyson?

  If, if, if the whole point is to have rubber grip into the texture of the track, why not actually chew up the track? So that the rubber is getting so in there, it's not even about friction. It's actually pushing off of vertical walls that have been cut into the track as you go around.

• 28:23Speaker 03

  Yeah, I think, I think the argument really is about you want to keep this a fast sport. Right. And friction, you need some of it in order to, you know, get the traction on the road to, to propel yourself forward. So you do need some friction. But if it's too high, then your car has a very, a much lower maximum speed. Right. It reduces how fast your car can go. So you've got the, and it's with friction.

• 28:48Chuck Nice?

  So this is the point of equilibrium.

• 28:50Speaker 03

  Yeah.

• 28:50Chuck Nice?

  You gotta, you gotta find that, that, that balance point.

• 28:52Speaker 03

  Yeah, there's always a balance. There's always a compromise. Like you need some, but not too much. And then if you're, you know, if you're looking, if you're looking at like an ice sport, like it, like skiing or something like that, you're looking at trying to minimize friction. But it's always, you do need some, but just not everything. Cause if you have too much friction, things just grind to a halt.

• 29:13Gary O'Reilly?

  Laurie, about 50 years ago, Formula One stumbled across a thing called carbon carbon. If I'm not mistaken. Um, and since then it's been part of the suspension shuttle. What's the, what's the connection?

• 29:27Speaker 03

  Yeah, carbon carbon is one of the materials that's used a lot in Formula One because it's very, very strong and it's very, very light. Um, and it's used, it's in Formula One's context, it's used in brakes. So it's used as a, as a lightweight way to produce a strong surface. And that you can, you know, interact with. Um, and as with most things, you know, they find applications elsewhere. I don't actually know which one came first in terms of carbon carbon, whether it was developed specifically for Formula One or whether it came about as a byproduct of, of another industry. Um, but yeah, it is very much a, it is very important material now in Formula One.

• 30:05Neil deGrasse Tyson?

  Wait, Laurie, forgive me, but can we be a little more explicit than just saying carbon carbon? Could you, could you tell me like what the hell that is?

• 30:13Chuck Nice?

  I've heard of Duran, I've, I've heard of Duran Duran and.

• 30:16Speaker 03

  No, fair point. Fair point.

• 30:18Chuck Nice?

  Yeah.

• 30:19Neil deGrasse Tyson?

  And New York, New York.

• 30:20Chuck Nice?

  Yeah, New York, New York.

• 30:24Chuck Nice?

  Sachi and Sachi.

• 30:26Speaker 03

  So like, yeah, no, no, that's fair point. So like, if you've heard of carbon fiber, you might have heard of that. It's carbon, you know, it's like long strands of of carbon fiber arranged in some sort of matrix, some sort of polymer. But carbon carbon is those carbon fibers that have been arranged in a matrix of graphite. So the the actual matrix itself is carbon, but just little flakes of carbon. And then the fibers going through it are these very aligned carbon fibers. So it is carbon and carbon in two different forms slammed together.

• 30:58Neil deGrasse Tyson?

  So two different forms of carbon. Okay. So if you threw in like diamond, you'd have carbon, carbon, carbon.

• 31:04Speaker 03

  Yeah, yeah, exactly, exactly.

• 31:05Neil deGrasse Tyson?

  Just check, just check.

• 31:06Speaker 03

  Carbon cubes.

• 31:08Neil deGrasse Tyson?

  And then as we found in the universe, as well as in the lab, there's buckyballs, right? Carbon sixty, another form of carbon. So just throw it all in there.

• 31:17Speaker 03

  Yeah.

• 31:17Neil deGrasse Tyson?

  Carbon, carbon, carbon.

• 31:18Speaker 03

  Exactly. Formula One has the money first, surely?

• 31:21Neil deGrasse Tyson?

  Yeah, they sure do.

• 31:24Gary O'Reilly?

  But they and they use that money to do something that I think a lot of people have been hoping to do for a long time, when they got a KERS system, the Kinetic Energy Recovery System. Um, and how advanced was their thinking to be able to bring that forward for motorsport? But we haven't seen it in the the general public.

• 31:46Chuck Nice?

  You see some, you see a version of it.

• 31:48Speaker 03

  Yeah.

• 31:48Neil deGrasse Tyson?

  Well, I have, I have a regenerative braking. Is that the same thing?

• 31:52Chuck Nice?

  Yeah, I was gonna say, that's a version of it.

• 31:53Speaker 03

  Yeah.

• 31:53Neil deGrasse Tyson?

  Regenerative braking.

• 31:54Speaker 03

  Yeah.

• 31:54Gary O'Reilly?

  All right.

• 31:55Speaker 03

  It is the same thing. It's once we started putting electric motors into our cars, that that becomes something that you can, that's a really useful form of of energy to capture. Yeah.

• 32:04Chuck Nice?

  Capture and return to the to the electric motor.

• 32:06Neil deGrasse Tyson?

  So what does it hand it to a flywheel or something? Or is it a, what, what, in what form is it, is it recaptured as?

• 32:15Speaker 03

  Um, as far.

• 32:16Chuck Nice?

  Yeah. And by the way, you should probably explain the whole concept because clearly we're all familiar. And I feel like we're a little inside baseball right now.

• 32:25Speaker 03

  Yeah, so it's like, it's what the idea-

• 32:28Neil deGrasse Tyson?

  Chuck, we're inside friction.

• 32:31Neil deGrasse Tyson?

  Well played, sir. Well played.

• 32:34Speaker 03

  Um, yeah, so the regenerative braking is effectively when you put the brake on, you effectively turn your motor into a generator. So you flip it around, you flip around its, its, uh, behavior. And so it generates electricity. And so, yeah, in a Formula One car, I believe it is just used in terms of electricity. It is just captured and used elsewhere in the car, but I'm actually not sure. So I won't pretend I know.

• 33:00Neil deGrasse Tyson?

  Wait, wait, just to be clear, you said when you put the brake on, let me, let me be, clarify that. What you mean is when you press the brake pedal-

• 33:08Speaker 03

  Yep.

• 33:09Neil deGrasse Tyson?

  Brake pads are not touching your wheel. What's happening is the forward motion of your car is getting sucked away-

• 33:18Speaker 03

  Yep.

• 33:19Neil deGrasse Tyson?

  Back into, isn't that what's happening? Yeah, that's it. Yep. That's, that's it. Yeah, yeah. So- Brilliant. Your kinetic energy is getting absorbed without even using friction-

• 33:30Speaker 03

  Yeah.

• 33:31Neil deGrasse Tyson?

  In that sense.

• 33:31Speaker 03

  Yeah, because usually brakes are just about like slamming on the friction as high as possible. But yeah.

• 33:37Neil deGrasse Tyson?

  Flintstone feet.

• 33:40Neil deGrasse Tyson?

  That's what they are. There you go. Do they have Flintstones in, in New Zealand? I don't know.

• 33:45Speaker 03

  Yeah, I remember them as a kid though. Yeah, I definitely watched the Flintstones.

• 33:48Neil deGrasse Tyson?

  Okay, good. Flintstones. Yeah, yeah. That's the accelerator pedal and the brakes.

• 33:52Speaker 03

  Yeah.

• 33:52Neil deGrasse Tyson?

  Yeah. Fred Flintstone, big old three-toed feet.

• 34:00Neil deGrasse Tyson?

  They have four fingers and three toes. That disturbed me more than the fact that they're living in the Stone Age with- Do you know that this is the first time that I have heard that? And I, and you're right. I'm- You never noticed that?

• 34:12Speaker 03

  I've never noticed.

• 34:13Neil deGrasse Tyson?

  I've never noticed that. Oh, my gosh! I have never- At least give the man four toes to match his four fingers.

• 34:20Gary O'Reilly?

  Isn't there something about when the animator draws a hand with four fingers and a thumb? It looks wrong. And so they, that's why they, they take away one finger.

• 34:30Neil deGrasse Tyson?

  Okay, so, so, so Gary, four fingers never looked right to me. Okay? Ever. And especially not the three toes with his big old caveman feet. So.

• 34:42Neil deGrasse Tyson?

  But they make great breaks. We gotta take a break. They're great recovery. We're talking about friction. We're talking about Formula One. We got rubber. We got Gecko feet. All in one frickin' conversation. Go figure. And at the center of all that is Lori Winkless. We'll be right back.

• 35:14Neil deGrasse Tyson?

  We're back. StarTalk Sports Edition. Everything friction and surfaces with one of the world's greatest exponents of this subject that I have ever seen. Lori Winkless, who's coming to us from from New Zealand. Lori, thanks for being on StarTalk and illuminating us with all of your surface wisdom.

• 35:34Speaker 03

  My pleasure.

• 35:37Neil deGrasse Tyson?

  So when someone says, you know, it's only skin deep, you're saying, yeah.

• 35:41Speaker 03

  Exactly.

• 35:43Neil deGrasse Tyson?

  That's where the action is. So, so we've talked about what you've learned sort of scientifically from Mother Nature. And at the end of the day, stuff only really happens if people can make money off of it. If there's sort of product developments. Applications. Applications that can improve what we already have or invent something new that we never thought we needed. So do you have some good examples of that, maybe?

• 36:11Speaker 03

  Yeah, I'll give you one that it's still, I would say, at the research end of the R and D scale, but it's pretty exciting. And if it works, it could give us boats that never get wet, which I think is pretty cool. It's based-

• 36:24Neil deGrasse Tyson?

  Boats that never get wet?

• 36:25Speaker 03

  They never get wet. No. So.

• 36:28Neil deGrasse Tyson?

  Wow. That's like Charlie and the Chocolate Factory, square sweets.

• 36:30Speaker 03

  Yeah, exactly. Precisely, Gary. Yeah.

• 36:34Chuck Nice?

  Okay. Yeah. So wait a minute, let me, let me just put this out. I mean, let me take this through. If the boat never gets wet, but it's moving through water, then that's about as frictionless as you could ever get. Yes, it's just moving through air. Super fast boat.

• 36:51Speaker 03

  Yeah.

• 36:52Chuck Nice?

  Is that right?

• 36:52Speaker 03

  Yeah. And you've got, if you think about the fact that like 90% of the world's trade happens by sea.

• 36:58Chuck Nice?

  Right.

• 36:58Speaker 03

  If we could reduce the friction that those massive container ships experience as they move through the water, you reduce the amount of fuel they use. You improve the environmental, you know, properties of that. So that is like something that a lot of different technologies are attempting to do. And you can already get boats that, you know, have a low friction coating on them. But one of the things I came across and I thought was really cool is there's this fern, it's called a salvinia fern, and it's usually like an invasive species. It, it forms these massive mats on the surface of, of waterways. So it can often cause that damage to anything living in the waterway. But the cool thing

• 37:38Speaker 03

  about it is that it is incredibly hydrophobic. So if you've heard of the lotus effect, which is this idea that the lotus is always pristine, water, nothing sticks to it, nothing ever, dirt doesn't touch it. It's kind of like that, but way better. It's way more impressive. And, and when scientists started to study what it is that makes this plant so good at repelling water, they started by looking at the surface. So in a way, it's kind of gecko-like. It's covered in loads and loads of hairs. And each one of those hairs is shaped a bit like a whisk, right? So it's kind of got four, it breaks into four that points the joint at the top. The whole leaf and all of these hairs are covered in a waxy surface,

• 38:20Speaker 03

  which makes it water repellent. But the cool thing is the very tip of that whisk is not water repellent. It's water attracting. It's hydrophilic. It attracts water. So what that means is that you trap a layer of air. The leaf traps a layer of air in its hairs. And because water is pinned on to the top of each one of those hairs, the air can't get out and the water can't penetrate in. So you have this permanent layer of air that the leaf has around itself.

• 38:53Neil deGrasse Tyson?

  You're really explaining kind of a microscopic hydrofoil.

• 38:57Speaker 03

  Yeah, well, this is, and this is where, when like, when this, when the botanists kind of realized that this is what's going on, they managed to recreate it. They managed to kind of produce coatings that have a similar structure, this combination of hydrophobic, so water repellent, and hydrophilic, water attracting, and capturing this band of air. So what they want to do is develop a coating that you could apply to a boat that retains a layer of air around it permanently, a stable layer of air. And there are some boats that have these, they produce bubbles, like there's an actual system that sprays out bubbles around the edge of a boat to try and reduce the friction in a similar way, but it's just not as stable as something that would be, you know, a solid layer of air.

• 39:41Neil deGrasse Tyson?

  Laurie, I thought I remembered a, was it a TV commercial? I might have been, I think it was YouTube surfing, I think I was. And I came across, it was like a container of mayonnaise and a container of ketchup. Yes! Two famously bottle-sticking substances. And they just tipped over the mayonnaise and all the mayonnaise just came right out of the container.

• 40:06Speaker 03

  Yeah.

• 40:06Neil deGrasse Tyson?

  They tipped the ketchup bottle and all the ketchup just came, nobody was shaking it or pounding it or squeezing it. Did it have one of these surfaces that you're talking about?

• 40:14Speaker 03

  No, it's actually got another surface that's called, yeah, it's called slick. There's so many, honestly, guys, there's so many.

• 40:20Neil deGrasse Tyson?

  There's so many surfaces! Out of control! Oh my goodness, we're filthy with surfaces!

• 40:25Speaker 03

  You see now why I had to write a whole book about them, because they're just amazing. Yeah, so that's a different material, actually. And what it does is that basically, they have, they put a coating that's porous, so it's got loads of holes in it, but then it's, those holes are filled with water. So it's kind of using water to stop other liquids from sticking to it. Um. So they've textured it in a way that um it traps its own little layer of of of water so that the ketchup then just falls out or the mayonnaise just falls out.

• 40:55Neil deGrasse Tyson?

  Just to show you how biased we are, just as members of civilization. I'm looking at that demo and I'm thinking, what's wrong with the ketchup?

• 41:02Chuck Nice?

  Exactly.

• 41:02Neil deGrasse Tyson?

  You know, I'm not eating that ketchup.

• 41:04Chuck Nice?

  Yeah, I'm not either.

• 41:05Neil deGrasse Tyson?

  It's a ketchup issue, not a surface issue. That's what I'm thinking to myself.

• 41:08Speaker 03

  It does look a bit creepy.

• 41:10Chuck Nice?

  It looks creepy. It's it, you know, it looks creepy.

• 41:13Neil deGrasse Tyson?

  God made ketchup to stick to the inside of a ball.

• 41:15Chuck Nice?

  Right. It's like seeing peanut butter slide out of a jar.

• 41:20Neil deGrasse Tyson?

  That's wrong.

• 41:20Chuck Nice?

  If you ever saw peanut butter slide out of anything, you would not.

• 41:24Neil deGrasse Tyson?

  Run, walk, don't run, run, don't walk, away from that.

• 41:27Chuck Nice?

  That peanut butter is sentient.

• 41:28Speaker 03

  Yeah. No, totally. It is quite disconcerting, I have to say, yeah.

• 41:33Chuck Nice?

  Exactly. Well, what about um when you talk about, so your um surfaces that slip and slide? Is there anything that can make something more aerodynamic? Like you put a coating on a football and now, uh, you know, instead of being able to throw it 30 yards, I can throw it 50 yards or kick it more, more importantly.

• 41:54Speaker 03

  Yeah, yeah, good point. And actually, that's kind of where like golf balls came from as well. Because the original golf balls were were smooth. And they were made from um basically they pack loads of a ball of leather with these feathers, make it really, really hard, smooth surface. But they realized that the ball would travel further when it had been dinged up a bit. So when it had some like dints in it, dents in it. So there was a scientist who decided that this was all a bit too, you know, experimental. So he wanted to do some proper analysis on it. And he designed what we now know.

• 42:26Chuck Nice?

  Anecdotal.

• 42:27Speaker 03

  Yeah, anecdotal. Yeah, sorry, excuse me. Yeah. So he wanted to do some proper experiments. Um. And yeah, he designed a pattern, which is now what we know as a golf ball pattern, this dimpled pattern. And that reduces the drag on a golf ball by playing with the way that. The air flows around it and and the formation of these little vortexes, these little areas of low pressure, and it that that dimple pattern kind of makes it plays around with turbulence in a in a way to reduce drag. So like a dimpled ball will travel about about twice as far as a smooth golf ball of the same dimensions.

• 43:05Neil deGrasse Tyson?

  So so it's really travelling in its own pocket of of low friction air. Is that a fair way to say that?

• 43:12Speaker 03

  Yeah, like everything moving through the air has a layer of kind of stuck air molecules right on its surface. And as the air, as you get further away from the surface, the air moves more and more and more. And

• 43:23Neil deGrasse Tyson?

  You know, air sticks to me all the time. I try to

• 43:26Speaker 03

  Exactly. It's a pain. It's so sticky, you don't even realise.

• 43:29Neil deGrasse Tyson?

  Who's ever thinking that way?

• 43:31Gary O'Reilly?

  So Laurie, is that is that the sort of thing that's going on with an aircraft, say, that was flying at thirty thousand feet? The temperature outside, the air temperature outside is minus something silly, right?

• 43:42Neil deGrasse Tyson?

  Forty below.

• 43:43Gary O'Reilly?

  And yet there's, yeah, and yet there's a an issue for overheating. What what what are we experiencing?

• 43:49Speaker 03

  Yeah, it's exactly that. It's skin friction. So it's effectively the air molecules bashing into other air molecules that are stuck onto the surface of of the aircraft. And even though at many, it depends on the altitude, of course, but the density of air can be lower than it is on this on the surface of the earth, there's still plenty of air molecules to bash into one another. So the the moving through the

• 44:14Neil deGrasse Tyson?

  Especially at five hundred miles an hour.

• 44:15Speaker 03

  Yeah, exactly. Moving through the air at high speeds, you are causing massive transfers of kinetic energy. You know, you are caught, you are bashing air molecules out of the way like crazy. And in that process, you you lose some some of that kinetic energy transforms into heat energy transforms into that the high temperatures on the surface. So like a lot of the very, very high speed aircrafts are and like reentry vehicles, they've been designed, their their surface chemistry has been really particularly designed to be able to cope with that happening on their surface. That's why, you know, heat, heat shields are so important. Yeah.

• 44:55Gary O'Reilly?

  I mean, we've discussed surfaces contacting each other, but we haven't discussed how we as humans interact with surfaces, particularly through our own skin.

• 45:07Gary O'Reilly?

  What, what happens at a molecular level? When we are touching and feeling surfaces?

• 45:14Chuck Nice?

  And how do I become Spider-Man with my own form of gecko feet?

• 45:17Speaker 03

  Well, yeah, there's a, there's a dude, I think it's at San Diego University, Chuck, who could sort you out. He developed a climber based on the gecko tape. So he managed to scale the building, well, a few stories of a building on his own.

• 45:29Chuck Nice?

  Wow, really?

• 45:30Speaker 03

  Yeah, yeah, Elliot Holt.

• 45:31Neil deGrasse Tyson?

  It depends if they do it at Stanford, yeah.

• 45:32Speaker 03

  Yeah, exactly. He was in that Stanford labs, yeah.

• 45:35Neil deGrasse Tyson?

  Yeah, yeah, yeah. But, but it is true, however, there are some things, um, you know, sometimes, I don't know, it depends on how oily or not your skin is, there could be something on a, on a, on the ground that you just touch it and it stick, like a playing card maybe will stick to your finger. Sometimes a penny might stick to your finger.

• 45:56Chuck Nice?

  Yeah.

• 45:57Neil deGrasse Tyson?

  Some light little things will stick to your finger.

• 46:00Speaker 03

  Yeah.

• 46:00Neil deGrasse Tyson?

  But I don't want to claim gecko powers.

• 46:02Speaker 03

  Nah.

• 46:02Neil deGrasse Tyson?

  Um, so what's going on with that when that happens?

• 46:05Speaker 03

  It's basically that we're a bit damp. Humans have this constant layer of water.

• 46:10Neil deGrasse Tyson?

  I thought it was gonna be a deep explanation, Laurie.

• 46:12Speaker 03

  No, unfortunately not. We're just a bit damp.

• 46:15Chuck Nice?

  It's just that we're, we're sweaty.

• 46:15Speaker 03

  Yeah. We just have water on us and usually that's enough to, you get effectively a capillary force, the, the water that are, you know, we are producing water all the time, we respire. And so we are constantly covered in a little, very thin layer of water. And sometimes that means that we can, you know, stick a spoon to our nose or we can pick up a piece of paper just by touching it.

• 46:39Chuck Nice?

  Oh, I thought it was the vaccine that made that happen.

• 46:41Speaker 03

  No, no.

• 46:41Neil deGrasse Tyson?

  Sticking this, sticking this to you.

• 46:44Chuck Nice?

  I thought it was the vaccine, just like, got vaccinated, look at me, I'm magnetic now. Uh, who's gonna fix this?

• 46:53Gary O'Reilly?

  All right, Laurie, before, before we, we, we have to let you go sadly, um, we, I mean, we're thrilled by the gecko, I think we all have.

• 47:02Neil deGrasse Tyson?

  Laurie, can you join the show?

• 47:03Speaker 03

  Yeah, sure. No problem. I do.

• 47:08Gary O'Reilly?

  Are there many other species out there that are kind of like owning it?

• 47:13Speaker 03

  Yes, yes. Sharks.

• 47:15Gary O'Reilly?

  Ooh, go on.

• 47:16Speaker 03

  Sharks.

• 47:17Chuck Nice?

  What?

• 47:17Speaker 03

  Sharks are.

• 47:19Gary O'Reilly?

  Fur, furry, furry cuddly sharks?

• 47:22Speaker 03

  Perfect.

• 47:23Chuck Nice?

  Okay, but wait a minute. Why would a shark need to grip anything?

• 47:27Neil deGrasse Tyson?

  Oh, she's talking about surfaces.

• 47:28Speaker 03

  The offices. Yeah.

• 47:30Chuck Nice?

  Oh, how they move through the water.

• 47:32Neil deGrasse Tyson?

  Who owns their surface?

• 47:34Speaker 03

  Yeah.

• 47:34Chuck Nice?

  Yes. There you go.

• 47:35Neil deGrasse Tyson?

  Okay, keep going, Laurie.

• 47:36Chuck Nice?

  I'm still stuck on Gekko.

• 47:37Speaker 03

  No, I don't believe you.

• 47:39Neil deGrasse Tyson?

  I see what you did there. Stuck on Gekko, yes. Okay. Go on, Laurie.

• 47:43Speaker 03

  No, sharks are...

• 47:43Neil deGrasse Tyson?

  Don't mind Chuck. Just ignore him. Go.

• 47:46Speaker 03

  Sharks are incredible. And if you look at their skin, and you don't even have to have a particularly fancy microscope. Don't do this to a living shark, right? I'm talking about like a museum. Don't touch a shark. But their skin is covered in these features called dermal denticles. And they're like very tiny scales. They're kind of like scales, but they're actually 3D. They're a real structure. And what scientists have realized is that we kind of knew that the shape and the placement of those denticles all over a shark's body must have something to do with reducing drag. It must have something to do with making it easier for them to move through the water. But what scientists realized in more recent years is that what's happening with these dermal denticles is that on some parts of a shark's body,

• 48:31Speaker 03

  it's the flow of water around this denticle actually behaves in a way as if it's gone in reverse. So it's as if the water is actually pushing the shark forward. It's not just reducing drag. It's actively helping the shark to accelerate through the water.

• 48:52Chuck Nice?

  So the shark is drafting itself?

• 48:55Speaker 03

  Yeah.

• 48:56Chuck Nice?

  Yeah. That is unbelievable.

• 48:58Speaker 03

  Yeah, they're incredible.

• 48:59Neil deGrasse Tyson?

  Okay, but wait a minute. Laurie, let's bring in some evolution here. Because, no, I got a question. You know, I can't claim to have hung out with sharks, okay? So I don't know of what I speak. But I don't picture sharks...

• 49:16Neil deGrasse Tyson?

  In high pursuit of their prey, I picture them stalking their prey. All right, and, and so why would speed have been selected for in their skin water surfaces? If that's not really what they're doing.

• 49:36Speaker 03

  Very good point. And they, I think the kind of the idea around it now is that these denticles have a different role to play on different parts of the body. So there are different sizes and shapes depending on, and they differ between species of sharks as well. So some sharks are more of a, they're more about speed, they're more about reducing drag. But in terms of increasing speed and reducing drag, really what that does is it decreases the amount of energy a shark needs to use to push its way through the water.

• 50:07Chuck Nice?

  And importantly, importantly, because sharks have to move in order to breathe, you would want that to, you would like that to be as, as easy as possible. Because when you do need to go hunt, you haven't used up all your energy swimming around so you can breathe.

• 50:23Speaker 03

  Yeah.

• 50:23Neil deGrasse Tyson?

  Yeah, I'll give you that because I, I just know that if sharks were fast moving, chase you down to meet predators, then you couldn't have that slow cello in Jaws.

• 50:38Neil deGrasse Tyson?

  You know, that, that, that, that, is it a cello or a bass?

• 50:44Chuck Nice?

  No, it's, it is, I think you're right, it's a cello.

• 50:46Neil deGrasse Tyson?

  It's a cello. So whichever it is, it's like, that's not the music you hear of something rapidly chasing something else. So it all worked out.

• 50:53Chuck Nice?

  Yeah.

• 50:53Neil deGrasse Tyson?

  It all worked out for the movie.

• 50:55Chuck Nice?

  And by the way, we're gonna need a bigger boat.

• 50:59Neil deGrasse Tyson?

  Chuck, you know, I thought you were above that, Chuck.

• 51:03Neil deGrasse Tyson?

  I've got the lowest hanging fruit. That fruit was already on the ground.

• 51:08Chuck Nice?

  If you ever mention Jaws, I have to say that. I can't, I have to. It's a law.

• 51:17Neil deGrasse Tyson?

  So Laurie, we gotta, I think we gotta close this out. Do you have a social media we can track you down on?

• 51:22Speaker 03

  Yeah, I'm on Twitter, like way too much. So I'm at Laurie underscore winkless on there.

• 51:28Neil deGrasse Tyson?

  And winkless is just wink and then less?

• 51:30Speaker 03

  Yes, wink less.

• 51:31Neil deGrasse Tyson?

  Very good. And your books, tell me the titles again, they're so great.

• 51:34Speaker 03

  Oh, yeah. So Sticky is just out. It's literally just came out a month ago in the US. And so Sticky, The Secret Science of Surfaces. And my older book is Science and the City. And that's all about how cities work and, and what happens in the, in the metropolis.

• 51:49Neil deGrasse Tyson?

  This is beautiful. I love it. I love it. And what are you working on now? What can we, in the future? Because we totally want to bring you back. Give us an excuse to bring you back.

• 51:58Speaker 03

  And what I'm working on right now is an article on chocolate making, physics of chocolate making, which is something I'm finding quite interesting. And but I've no new.

• 52:05Neil deGrasse Tyson?

  Okay, can we book you tomorrow?

• 52:07Speaker 03

  I have to learn about it, yes.

• 52:08Chuck Nice?

  And by the way, by the way, can we, can we, can we do some research for you?

• 52:12Speaker 03

  Yeah, I'll send you some samples. But yeah, nothing else immediate. No, no more books in the immediate pipeline, anyway. Take a break for a little while.

• 52:20Neil deGrasse Tyson?

  Very cool. So, all right, guys, we're calling, we, we gotta end it there. So Gary, Chuck, always good to have you doing this, man.

• 52:27Chuck Nice?

  Pleasure.

• 52:27Gary O'Reilly?

  Pleasure.

• 52:28Neil deGrasse Tyson?

  All right. And Laurie, it's been a delight to have you on this program. We learned so much about stuff we didn't even know there was something to learn about. So that's always a good day. At, at, at least for me and I'm sure for Chuck and Gary.

• 52:40Speaker 03

  It was super fun. I listened to the show, so it was really fun to, to be on it.

• 52:44Neil deGrasse Tyson?

  Oh, you do? Okay, well, thanks, you're a fan.

• 52:46Chuck Nice?

  Aye.

• 52:47Neil deGrasse Tyson?

  Excellent, excellent. So I hope we lived up to your expectations.

• 52:50Speaker 03

  Very much.

• 52:51Neil deGrasse Tyson?

  You certainly exceeded ours. So, all right, this has been StarTalk Sports Edition. Neil deGrasse Tyson, as always, bidding you to keep looking up.