Cosmic Queries – Winter Olympics Grab Bag with Charles Liu

What's ice skating like on Titan? On this episode, Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly answer fan questions about the physics involved in the Winter Olympics with Charles Liu.

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 Sports Edition, a Cosmic Queries version. We're going to talk about the Winter Olympics. Ooh, yeah. We've got Gary O'Reilly. Gary?

• 0:24Gary O'Reilly?

  Hey, Neil.

• 0:25Neil deGrasse Tyson?

  Yeah, do they play soccer in the snow? Do they play soccer in the snow?

• 0:30Gary O'Reilly?

  Yeah, we will do. It depends. If it's too bad, no, because the ball doesn't roll. But, uh, yeah, we'll play frozen and in the snow.

• 0:37Neil deGrasse Tyson?

  I got you, got you. And Chuck, you avoid cold weather at all costs.

• 0:41Chuck Nice?

  Uh, yes, I've, it's a, it's an homage to my ancestors.

• 0:49Chuck Nice?

  Yes, all of, for all that came out of the Serengeti. I'm, I'm representing.

• 1:01Neil deGrasse Tyson?

  So, uh, this is a very broad topic because we want to talk about, uh, the Olympics in general, the Winter Olympics, the events, the fact that it's in Beijing. And, you know, anytime we have a broad subject like this, there's only one go-to person, and that's our geek-in-chief, the one and only, my friend and colleague, Charles Luke. Charles, welcome back to StarTalk for the 100 and zillionth time.

• 1:25Charles Liu?

  Thank you, Neil. It's my pleasure. Thank you. Hello, Gary. Hello, Chuck. Or should I say Lord Nice?

• 1:34Charles Liu?

  Oh, my God.

• 1:35Neil deGrasse Tyson?

  You were on that episode.

• 1:37Charles Liu?

  Yes. Does everybody know that it was Major General Deanna Burt that, uh, anointed Chuck Nice with this, uh, title?

• 1:45Chuck Nice?

  With the, with the lordship. He certainly did.

• 1:48Neil deGrasse Tyson?

  Yeah. And it comes in, it comes in, and I always forget, and people remind me. Uh, so, so Charles, you, you are a professor of astronomy and physics at the City University of New York at Staten Island.

• 2:00Charles Liu?

  Correct.

• 2:00Neil deGrasse Tyson?

  And you've recently been, uh, become Chair of the Department. Is that correct?

• 2:04Charles Liu?

  Yes, yes. And, uh, it's been fun. I, I have some great colleagues, some wonderful students, and, uh, if anybody watches, uh, The Chair, the TV show that's become popular lately, that's like 5% of maybe my regular life, but, uh, it's a lot of fun. I have a good time with it.

• 2:22Neil deGrasse Tyson?

  Okay, so I smell a reality show in the making here. Where Charles really shows what this is about.

• 2:29Chuck Nice?

  We'll call it the lounge chair.

• 2:32Neil deGrasse Tyson?

  Ah, good one, Chuck. Good one.

• 2:35Charles Liu?

  The satie.

• 2:36Neil deGrasse Tyson?

  Yeah, Chuck. And Charles, you know, hearing from the grapevine, you've got a podcast in the making.

• 2:44Charles Liu?

  Oh, yes.

• 2:45Neil deGrasse Tyson?

  So we all look forward to seeing that post.

• 2:47Charles Liu?

  Thank you, thank you.

• 2:48Neil deGrasse Tyson?

  And you told me offline that it's called the, it's called the Luniverse.

• 2:54Charles Liu?

  Yes. The Luniverse, yes. Well, you know.

• 2:58Neil deGrasse Tyson?

  Charles Liu.

• 2:59Charles Liu?

  I didn't come up with it, you know. Family members around the dining room table, they were like, why don't you call it the Luniverse? I said, really? They said, yeah, sure, why not? It should be fun. We're really looking forward to it. It should be a lot of fun. We're talking with fun folks. We'll have a good time. Thank you.

• 3:15Neil deGrasse Tyson?

  Excellent, excellent. Right now, it's a Cosmic Queries grab bag on the 2022 Olympics, taking place in Beijing. So, so the questions are open for anybody and anything. And Gary, Chuck, who between you has the questions for us?

• 3:29Gary O'Reilly?

  Chuck and I can share them between ourselves. Let us kick it off. Welcome to Charles, obviously. Great to have you back. Right, Michaela Nagus. These are all questions to my Patreon listeners.

• 3:43Chuck Nice?

  Oh, okay. Oh, I got nervous for a second.

• 3:49Gary O'Reilly?

  All right, just working on my pronunciation here. I couldn't trip up on that one too quickly, could I?

• 3:55Charles Liu?

  You're unfamiliar.

• 3:55Neil deGrasse Tyson?

  Yeah, we have to meet.

• 3:56Gary O'Reilly?

  Why does?

• 3:57Charles Liu?

  You're unfamiliar with the.

• 3:58Neil deGrasse Tyson?

  Meet you outside for that one.

• 3:59Charles Liu?

  You're all familiar with the Grand Nagus, right, from Star Trek: Deep Space Nine?

• 4:04Chuck Nice?

  I am, as a matter of fact, yes.

• 4:06Neil deGrasse Tyson?

  I am not, I'm sorry.

• 4:07Gary O'Reilly?

  I know, Charles can't resist, Chuck rather, can't resist just tweaking my funny bone every now and again. So, why does the temperature of Olympic ice need to be different for figure skating, speed skating, and hockey? Could an ingredient be added to the ice to make it more ideal for the athletes, for example, making it smoother, harder, softer, etc.?

• 4:28Neil deGrasse Tyson?

  Wow, I didn't even know that.

• 4:30Charles Liu?

  Yeah.

• 4:31Neil deGrasse Tyson?

  Chuck, Charles, did you know that?

• 4:32Charles Liu?

  Ice changes all the time.

• 4:33Neil deGrasse Tyson?

  Of course you know it.

• 4:34Charles Liu?

  Ice is.

• 4:37Charles Liu?

  Ice for sports.

• 4:38Neil deGrasse Tyson?

  Let's wait for basic, wait, wait, basic fact. Are all three of those ices pure water? Or have they added anything to it?

• 4:47Charles Liu?

  Uh, usually, things have been added. Uh, they are often pure water. Uh, but if they are pure water, even then, there's changes because they change the temperature. They freeze it at different temperatures, hot or cold. Just because something's freezing doesn't mean that it stays at that same sort of texture and temperature the whole time. Uh, this is actually used on purpose in a lot of different places. Uh, there's a famous example in ice hockey, in college hockey. Depending on where you go to play your hockey, the ice is either really fast or really slow.

• 5:18Neil deGrasse Tyson?

  What really slow?

• 5:18Charles Liu?

  Uh, depends on their team, you know, uh.

• 5:21Neil deGrasse Tyson?

  Wait, is this like the deflate gate with this Tom Brady?

• 5:24Charles Liu?

  Yes.

• 5:24Neil deGrasse Tyson?

  Where you can change?

• 5:25Charles Liu?

  Yes.

• 5:26Gary O'Reilly?

  Well, no, it happens naturally, Neil. So for instance, the Canadians have, Charles, back me up on this if I'm, if I'm right or wrong. Um, the Canadians have just historically hard ice. But if you go and play hockey in LA and someone's left these, or the, the arena doors open for a while and that hot air comes in, it affects the quality of the ice.

• 5:45Charles Liu?

  And the refrigeration underneath the ice, of course, can be strongly, uh, adjusted to any situation if you have an indoor rink, right? So what happens with indoor activity is, uh, for example.

• 5:55Neil deGrasse Tyson?

  Wait, Charles, I just got to establish here.

• 5:57Charles Liu?

  Sure.

• 5:58Neil deGrasse Tyson?

  I just have to establish here because I think some people might not know this.

• 6:01Charles Liu?

  Okay.

• 6:01Neil deGrasse Tyson?

  I think you were hinting at it, but let me just, let me just drive it home. Water freezes at zero degrees Celsius, thirty-two degrees Fahrenheit.

• 6:11Charles Liu?

  Hmm.

• 6:12Neil deGrasse Tyson?

  And we call that ice, but you can have ice at any temperature below that.

• 6:17Charles Liu?

  Correct.

• 6:18Neil deGrasse Tyson?

  And the properties are different depending on what temperature the ice is. So ice is not ice.

• 6:23Charles Liu?

  Correct.

• 6:24Neil deGrasse Tyson?

  It depends on how cold the ice is.

• 6:28Charles Liu?

  Yes. That is exactly true.

• 6:30Chuck Nice?

  And at what, what temperature does it get down to gangster rap? Like Ice T and Ice Cube?

• 6:37Charles Liu?

  Well.

• 6:39Charles Liu?

  Nice that you should mention that. On Titan, right, the moon of Saturn, the temperature of the ice is hundreds of degrees below zero Fahrenheit. And so the water ice is as hard there as granite is here on this earth. So they build mountains with it. You can see all kinds of geological features that's built with water ice that you could not do here because the moment you try to do that. What do you mean, "they" built the ice? You're talking about aliens on Titan. I was gonna let that one go. They built the ice. That's an excellent point. Who is "they"?

• 7:11Charles Liu?

  "They" built the... "They" built mountains on Titan, yeah. But the answer, bottom line, Gary. You're not allowed to divulge anything more than that.

• 7:21Charles Liu?

  Yes, Gary. The temperature varies and each rink does its own thing. And each sport has its own regulations as to what you are allowed to do in terms of temperature, in terms of additives, in terms of those sorts of things, right?

• 7:37Gary O'Reilly?

  Yeah, the hockey players don't like soft ice.

• 7:39Charles Liu?

  Some hockey players love soft ice.

• 7:41Gary O'Reilly?

  As sweetly, yeah.

• 7:42Charles Liu?

  Think of the very large, bulky folks who, like the Wayne Gretzky's of the world, would zip right by, right?

• 7:48Chuck Nice?

  The slow guys. The slow guys like the softer ice.

• 7:51Charles Liu?

  And there are famous or infamous examples of really good hockey teams with fast skaters going into a visiting rink where the players are slow and suddenly it's like they're on molasses. And you see like water spraying off. That's Tom Brady letting the air out of the ball.

• 8:07Chuck Nice?

  Yeah.

• 8:07Charles Liu?

  That's Tom Brady letting the air out of the ball. Kind of like that, very kind of like that, yeah.

• 8:11Chuck Nice?

  So is there... Is it possible to get ice so hard that like a speed skater's blade wouldn't even allow it to turn? Like you would literally skid across the ice instead of skate across it?

• 8:26Charles Liu?

  On Earth's surface, probably not. But elsewhere in the universe, for sure and absolutely. Oh, cool, cool.

• 8:36Gary O'Reilly?

  Oh. Interscale of skating.

• 8:40Neil deGrasse Tyson?

  Okay, so it's all about what kind of speed that they want. So figure skating versus hockey versus speed skating. Then it's it's pretty clear. You just you can put that on a chart.

• 8:51Charles Liu?

  You you kind of can, yeah. Um, yeah, and and remember what the skates look like, right? A hockey skate is straight. The blade is straight. The figure skate's got a little uh divvety thing right at the tip. So you can dig into the ice and jump up and do your spins and things like that. And if your ice is too hard, then it can't. It doesn't make a difference. Right? But if it's too soft, then you also can't dig very much because you've got this sort of layer of of soft stuff. So, yeah, people have to just very, very carefully.

• 9:19Neil deGrasse Tyson?

  So Charles, one other thing. Why are speed skates longer in their blade than hockey skates?

• 9:26Charles Liu?

  Well, um, I presume that has something to do with the ability for you to push off and get higher velocities going in a straight direction, right? I mean, Gary, you're probably more an expert about in terms of the relationship between how long you can push, say, off the ground or something, and thus the law, how much stride you can get, how much speed you can pick up, the kind of acceleration explosiveness you can have.

• 9:50Gary O'Reilly?

  The my, is there a relationship to the amount of time the skate stays on the ice? And you're able to impart energy through that. So therefore, a a longer skate allows you that fraction more contact with the ice and therefore pushing energy in to push to get.

• 10:05Charles Liu?

  Yeah, I bet you that's true. And if you want to stop too, a longer blade gives you more when you're at at a forty five or ninety degree angle, you're able to break faster. Right? Because you have more of a surface with which to push friction against the ice.

• 10:20Neil deGrasse Tyson?

  Mm hmm, mm hmm, mm hmm. All right. All right, temperature of the ice. Okay, you have more questions?

• 10:27Gary O'Reilly?

  Of course, we have a very curious audience, Neil. All right, Dylan, or DeLeon, if Chuck prefers me to pronounce it like that. Hello, Dr. Tyson, Dr. Lou, and our great comedic co-host, yes, of course. I love to ski and have always wondered something. This is from Dylan, of course. Snow and ice aren't exactly the same things, and we know ice has a thin layer of water, less than the width of a bacteria, he believes, which makes ice sports possible such as skating. Does skiing also have to do with pressure melting? Or is there something else going on with snow?

• 10:59Charles Liu?

  Wow. The answer is both are true. The snow is an even-

• 11:06Neil deGrasse Tyson?

  Wait, wait, first explain pressure melting.

• 11:08Charles Liu?

  Yeah. Well, there is a relationship where if you have more pressure on water or ice, it is more likely to melt. This is untrue for most substances. But the more you push on something, the more you push on ice, the more likely it is to be able to liquefy. This is a particular property of ice which is rare amongst substances here on Earth. And that allows us to be able to do these things like skate across ice with that tiny film of water, that bacteria-filled film of water that we talk about. But it's a very complicated system. It's not just-

• 11:46Chuck Nice?

  Wait, wait, what's the, what is the molecular transaction that's happening where pushing pressure causes melting? Because that's how they make the big ice balls for my scotch.

• 12:00Charles Liu?

  That is how they do it, right?

• 12:02Chuck Nice?

  Yeah, I never questioned it.

• 12:03Charles Liu?

  You take the snow, you smoosh it, whoa, there's your ice ball right there.

• 12:06Chuck Nice?

  Right, I never, I never questioned it because I'm about to drink some scotch, so I don't care. But what is, what is the molecular transaction that the pushing makes the melting?

• 12:16Charles Liu?

  Well, we shouldn't get too deeply into the specific chemistry right now because it takes a long time to sort of make the descriptions. But basically, a water molecule is a V shape. Right? It's it's got the oxygen in the middle and it's got two hydrogens off to the side making kind of a V. It's a polar molecule like this. And when ice freezes, it has a tendency just to touch on the hydrogen bonds. It doesn't want to just squish in, but it wants to form a hydrogen bond lattice or a crystal. And as a result, it winds up with extra space between the molecules, space that would not have existed in its ordinary liquid form. Okay. And so that basically allows all kinds of strange things to happen.

• 12:59Charles Liu?

  And so snow is ice-y water, right? It's solid water, but it's in small crystals as opposed to one big slab of solid material. So when you pack a whole lot of little things together and you create a surface, it's a different surface altogether from if you have a single slab of the same object, everything's stuck together. The difference between, say, a sandstone walkway and a sandy beach. So, snow gives you even more variation on, say, going across its surface than the sliding across a slab of ice. So, the answer to the

• 13:38Charles Liu?

  question here is indeed that snow variations, changes, temperature, pressure, weather, wind, will make all the difference in the world when it comes to a snow sport.

• 13:51Neil deGrasse Tyson?

  But in fact, if you if you ski a lot on a fluffy snow slope, it eventually becomes sort of, you've melted many of the surface layers of crystals of of snowflakes, and eventually it just becomes icy. It's no longer fun to ski on.

• 14:08Charles Liu?

  You will start packing it down more and more.

• 14:10Neil deGrasse Tyson?

  Packing it too much.

• 14:11Gary O'Reilly?

  But then again, if you're in competition, Neil, you want to go faster. So icy quicker, fluffy powdery snow slower.

• 14:18Chuck Nice?

  But there's a very delicate equilibrium that you have to find because if it's too icy, you can't turn. So in the giant slalom, you want a kind of nice balance between that powdery and that icy, so you can grip with the edges of your ski, but yet at the same time, you can achieve the the the turning. So you have the fast and the turning at the same time. But but.

• 14:43Gary O'Reilly?

  Chuck, you know the deal. If it's too icy, you find the way to go.

• 14:48Neil deGrasse Tyson?

  But Chuck, we established in a previous episode that we're not taking skiing advice from you.

• 14:54Neil deGrasse Tyson?

  We are, we are.

• 14:56Chuck Nice?

  We're not taking

• 14:57Neil deGrasse Tyson?

  Oh, we're taking skin and ice and ch-

• 14:59Chuck Nice?

  ... advice from the dude who's sitting by the fire in the lodge.

• 15:04Chuck Nice?

  I'm sitting by the fire with some brandy, just like, "You do realize the reason you weren't able to turn it was because..."

• 15:13Neil deGrasse Tyson?

  Before we take a break, I want to add something to what Charles said. So, because water expands when it freezes, it can only exist in that expanded state as ice. If you successfully squeeze it, it cannot be squozed as ice. The only way you can squeeze it is for it to change state and then become smaller in its volume. And so, so, so that's why. So you're skating on the ice. The pressure forces it to turn back into water, even at the lower temperature.

• 15:48Charles Liu?

  That is exactly right. And, and then the, if you're doing, going down a ski slope or a toboggan slope, you know, like a bobsled or something, remember, a lot of that stuff is outdoors. So what if it starts to snow? Then you have even more stuff on there. It gets even more complicated. The weather makes all the difference in the world. I remember, uh, 1984, I think it was, the Sarajevo Winter Olympics. Billy Johnson, the American, was the first person down the mountain. And then the weather got worse and worse and worse. And all the rest of the competitors could not keep up with that first time because that first time was the ideal condition, regardless of what anything else happened with the surface, because the atmospheric conditions had changed.

• 16:32Neil deGrasse Tyson?

  Dude. All right. We're gonna take a quick break. When we come back, more Cosmic Queries Grab Bag on the Winter Olympics with our Geek in Chief, Charles Liu.

• 16:57Neil deGrasse Tyson?

  We're back. StarTalk, sports edition. Cosmic Queries Grab Bag got Charles Liu, who's our go-to person. Anytime, we're all just confused about everything.

• 17:09Charles Liu?

  It's always a pleasure to be here. Always fun to chat with everybody.

• 17:13Neil deGrasse Tyson?

  So, we're just pulling questions out of this grab bag. And Chuck or Gary, who's got the next one?

• 17:20Gary O'Reilly?

  Okay, I'll jump in. Right, Eric Varga says, "Hello, Dr. Tyson, Dr. Liu, but he's downgraded you, Chuck. You're now sir Chuck."

• 17:27Neil deGrasse Tyson?

  Oh.

• 17:28Gary O'Reilly?

  You've lost your lordship.

• 17:31Neil deGrasse Tyson?

  Eric, he doesn't know that sir is a lord. He doesn't know that.

• 17:36Gary O'Reilly?

  Oh, God, yes. Yeah, he does now.

• 17:37Neil deGrasse Tyson?

  Or maybe he's very well aware.

• 17:43Gary O'Reilly?

  All right. "Can you explain how Newton's three laws apply to the sport of curling? Are there any other laws of physics involved that play a vital role in advances assistance?"

• 17:53Neil deGrasse Tyson?

  Wait, did the word "sport" and the word "curling" show up in the same phrase?

• 17:56Charles Liu?

  Oh.

• 17:57Gary O'Reilly?

  Absolutely.

• 17:58Charles Liu?

  Don't be such a snob. Curling is a distinguished sport.

• 18:02Neil deGrasse Tyson?

  I have to say that. It had to come up.

• 18:04Gary O'Reilly?

  Go, go, go, go, go, go, go, go.

• 18:06Charles Liu?

  Oh, that's the best.

• 18:07Gary O'Reilly?

  Neil, curling is one of the oldest team sports in existence.

• 18:12Neil deGrasse Tyson?

  So?

• 18:14Gary O'Reilly?

  Look, this show's gonna come with a history lesson, whether you like it or not, right? So, okay, first invented in Scotland, and the first documented match was between a monk and an abbot in Paisley Abbey in Scotland in 1541. So, the moral of this history is when you lock people up in a monastery for a long time during winter, they come up with curling. Just saying. Curling, the sport of sexual frustration. Curling.

• 18:44Gary O'Reilly?

  So, about Newton's three laws of physics and anything else you can throw at curling.

• 18:47Charles Liu?

  Well, Newton's three laws, as most of us know, is that first law, right? An object in motion tends to stay in motion in a straight line unless acted upon by an outside force. So... The guy pushing the stone forward, it's just gonna keep going and going and going. And that's why you notice that it keeps going and going and going, unless acted upon by an outside force. Okay, now, the second law of motion, uh, forces, mass times acceleration. Wait, wait, just to be clear, it keeps going because the friction is very low. Otherwise, the friction would stop it, right? Well, you are front-running me on that point, Neil. You're absolutely right. No, no, no, it's good, it's good. Okay. See, cuz, cuz you're doing exactly what scientists should be doing, right? Which is jumping in and saying, ah, but, right?

• 19:32Charles Liu?

  And the but is Newton's second law, which, as you know, is forces, mass times acceleration. What is causing... It's also Sir, it's also Sir Micksalot's first law. I like big, okay, never mind.

• 19:48Charles Liu?

  The, the... All right, go ahead. What creates, what is creating the mass times acceleration, right? That's the second thing, that's what Neil is bringing up. And friction, as it turns out, will cause mass times acceleration to be exerted on the stone that's moving forward. And so, the second law requires that you wind up making sure that the friction is just right. So, the amount of force and acceleration that you get, the change in direction and then the change in speed is what you want. So, those guys in the broom up front, they are quickly changing the coefficient of friction of the ice on the whole time. The, the brushing? Uh, I, I, I've never known if exactly before every run,

• 20:30Charles Liu?

  uh, the curling people, uh, put like a whole bunch of snow or shaved ice on the track ahead of time. Yeah, what are they, what are they brushing? Yeah, that's what's my question, what are they brushing?

• 20:41Gary O'Reilly?

  Charles, okay, do you know, so curling, curling, curling ice, right? Back in the 16th century, when curling was invented, it was taken place on loch, frozen lochs and frozen ponds. So, what you have, have now with indoor curling ice is pebbly. It's not a smooth silk finish, it's pebbly. So, what the guys with the brooms are doing, they are taking away those pebbles as much as they can in a certain way. And the big clue about what this sport's all about is in the title. Curling. Cuz a, a stone will curl maybe three times on its way to the target, or it might curl 10. But the deviation is the...

• 21:17Charles Liu?

  And therein lies the third law, Newton's third law of motion. When it reaches its destination in the curled direction it wants, it hits other stones. And for every action, there is an equal and opposite reaction.

• 21:32Charles Liu?

  That's Newton's third law. So the stone hits the other stones that are in the scoring area, either knocks them out or pushes them a little bit. So Newton's laws of motion are involved in all stages of this exciting, thrilling, super fast, high-energy sport called curling.

• 21:50Chuck Nice?

  Hey! Yeah, man. Wait, wait, wait. Let me just say this. As a former janitor, curling is the best sport ever.

• 21:58Neil deGrasse Tyson?

  Wait, so, so Charles, something I never thought about.

• 22:04Charles Liu?

  Yeah.

• 22:05Neil deGrasse Tyson?

  So as they're brooming material into the path of the, of the, I keep thinking curling iron, curling stone, they're, they can, they can slow it down, but they can't speed it up because it only has the speed it has at that moment. But they can also change its direction.

• 22:23Charles Liu?

  Yeah, absolutely.

• 22:24Neil deGrasse Tyson?

  By putting more friction on one side of it than the other.

• 22:28Charles Liu?

  Right.

• 22:29Neil deGrasse Tyson?

  Man.

• 22:30Charles Liu?

  Right. So, so the, the physics of the brooming people is extremely significant. The, the push, once the, the pusher pushes the stone off, his work is done. And all the rest of the team has to figure out where to push it forward based on the pebble-iness or the shaviness of the ice.

• 22:48Gary O'Reilly?

  So here's, here's something to add to this conversation. As I think you'll understand, I don't get a chance to do this very often, but the curling stone is not flat on the base. It's actually concave. So it has a rim around it. So when it's traveling forward, the likelihood, and please disprove me, is that there's a little tilt on the front edge, which causes a little bit more friction, and then you've got an added rotation to the stone. So is that making sense to you, Charles?

• 23:15Charles Liu?

  Well, it does in a, in an important, generalized way. We talk very glibly about ice melting and pushing and things like that. But actually, the surface physics, the connections between surfaces of ice and curling or skis or anything like that is still rather poorly understood. A lot of it is still under experimentation today at the highest levels. What happens when one surface touches another? And that physics right at the edge there remains mysterious in a lot of different ways. So many hypotheses have to be put forward, and then they're either confirmed or debunked, depending on the circumstances of the time. But it's a very complex question. So what you bring up is definitely an area for future study and research.

• 23:58Neil deGrasse Tyson?

  I would add that if you if you've ever gotten your brakes changed on your car.

• 24:02Charles Liu?

  Nah.

• 24:03Neil deGrasse Tyson?

  Generally, the front brakes wear out sooner than the rear brakes. Because when you stop the car, the momentum of the car is carried more in the front wheels than in the back wheels. So Gary, that's my that's my conduit to what you said. Where if it's going forward and there's any friction slowing it down at all, that front edge is going to respond to it more significantly than the rear edge.

• 24:30Gary O'Reilly?

  Then again, you have to go from front-engined vehicles to mid-engined vehicles where there's weight distribution. But that's another conversation for another time.

• 24:38Neil deGrasse Tyson?

  Wait, Charles, what do you know about that? If you're in a rear-wheel car, isn't it still the front brakes that get most of the wear?

• 24:45Charles Liu?

  It varies a lot. Again, if you're driving.

• 24:49Neil deGrasse Tyson?

  It might change if you just move the engine to the back.

• 24:51Charles Liu?

  Right. Well, it depends on if you're moving on a flat surface or whether you're climbing hills. Are you stopping a lot while you're going upward or downward? You are pushing more of your your mass and force forward to the front because a car, even though it feels like a rigid body, actually has a great deal of give to it, right? A lot of springs, a lot of flexible parts to it. So it's not a dead-set thing. With with our typical driving in suburbia, for example, I think, Neil, you're right on. But the complexity of driving gives us all plenty of fodder or area to be right or wrong on these.

• 25:27Chuck Nice?

  And what about the Flintstone car?

• 25:30Charles Liu?

  Well, you should check out Fred's heels. Now, those brake pads are some serious calluses, I gotta tell you.

• 25:40Gary O'Reilly?

  All right, let's let's jump to another question. And all these questions are from our Patreon listeners, so we're grateful for that. Artist formerly known as James Smith hallows Doctors and Lords, Chuck, congrats on your land in Scotland. So there you go. Quick question, bobsledding is an awesome sport to watch. How many Gs are the bobsledders experiencing at top speed? And also, are there Zambonis for their eyes like in skating?

• 26:05Neil deGrasse Tyson?

  Oh, that's cool.

• 26:07Charles Liu?

  Yes.

• 26:08Chuck Nice?

  Good question.

• 26:08Charles Liu?

  The answer is, let's see. The Zamboni question first. There actually is a lot of grooming of bobsled runs. I do not know exactly whether they drive a vehicle down, you know, like a little crawler.

• 26:20Chuck Nice?

  Can you imagine?

• 26:22Charles Liu?

  I do not know if that's the answer. But they pour water down them, they sculpt them. There are things that are made and changed. The channels are changed, the temperature is controlled. So there is a lot going on that's Zamboni-like on a bobsled run. That's 100% true.

• 26:36Chuck Nice?

  And during the competition, there are like track grooves that are created by the form of runs.

• 26:42Charles Liu?

  Right.

• 26:43Chuck Nice?

  And you have to actually compensate for the track grooves that are already there. The person who is actually pulling the two cords.

• 26:50Charles Liu?

  The driver of the sled.

• 26:51Chuck Nice?

  The driver. The latest, yeah.

• 26:53Charles Liu?

  Yeah.

• 26:54Neil deGrasse Tyson?

  You're up chuck at the fireplace, Sipping Scotts.

• 26:59Chuck Nice?

  Once, once again, I'm down to the last. I'm just like, you do realize that you didn't account for the track grooves? This is your problem, sir.

• 27:09Neil deGrasse Tyson?

  Also, I want to add one thing before we take a quick break. The G-forces you feel have nothing to do with how fast you're moving. They have to do with how fast your velocity is changing. So their biggest G-forces, Charles, are going to be like when they bank the turn.

• 27:27Charles Liu?

  A G, right? A G is the acceleration rate of 9.8 meters per second squared. The amount of acceleration you feel when you're in free fall near the surface of the earth. I did a quick calculation just now in the past 30 seconds in my head. So I'm not sure if it's exactly right. You can't quote me on this. But based on what I think, how fast they're going down the hill, the angles of the turns and the velocities and the banks and so forth, you're probably hitting at least three and sometimes four times of gravity. So 30 to 40 meters per second squared of acceleration. So three or four Gs is my top of the head answer. I'd have to go back and do more calculation to make sure.

• 28:08Neil deGrasse Tyson?

  Cool, cool. All right, let's take a quick break. When we come back, more with Charles Liu, our geek in chief. Let's start talking, Charles.

• 28:25Neil deGrasse Tyson?

  We're back. StarTalk Cosmic Queries, Sports Edition, the Winter Olympics, all kinds of questions. We're good here. So, who's got the latest one?

• 28:33Gary O'Reilly?

  All right, here we go. Next up, Kevin the Sommelier. Hello Chuck Cubed and Gary. This is, you're gonna love the ending on this one, Neil. This is not so much a science question, but a Seinfeldian, Seinfeldian observation. Does the luge and the skeleton, well, we'll see. Does the luge and the skeleton events just seem like a drunk friend's dare? Keep drinking up.

• 28:57Gary O'Reilly?

  There, yeah, I told you you'd like that.

• 28:59Neil deGrasse Tyson?

  I'm certain.

• 29:00Gary O'Reilly?

  Nice one.

• 29:00Neil deGrasse Tyson?

  The luge is for crazy people.

• 29:04Gary O'Reilly?

  Oh, you can imagine, someone up, up the top of a mountain, sat next to Chuck with an empty bottle of Scotch, says, "There's that tray over there, I can beat you to the bottom of the mountain."

• 29:16Charles Liu?

  How many, wait, wait, have you all?

• 29:18Neil deGrasse Tyson?

  Wait a minute, which one is head first?

• 29:21Charles Liu?

  Skeleton is head first.

• 29:23Gary O'Reilly?

  Skeleton.

• 29:23Charles Liu?

  Luge is feet first.

• 29:24Gary O'Reilly?

  Skeleton's head first, yeah.

• 29:25Charles Liu?

  Okay. Yeah. I feel like luge is like safer, right? But how many of you, have you all gone down a hill in, in,

• 29:33Gary O'Reilly?

  Really?

• 29:34Charles Liu?

  sledding? How many of you, have you, three of you gone sledding before?

• 29:38Neil deGrasse Tyson?

  I mean, we have all been children, Charles, yes.

• 29:41Gary O'Reilly?

  Yeah, but we've not, we've not done it on an ice track.

• 29:44Charles Liu?

  As an adult, you know? Or the closest I came to that one, it was on an icy hill. Or it was maybe 40 feet tall. It was fantastic.

• 29:54Neil deGrasse Tyson?

  Wait, Charles.

• 29:55Charles Liu?

  Do you know how awesome it feels to go down a zillion miles an hour on the ice?

• 29:58Neil deGrasse Tyson?

  I learned from Chuck, I learned from Chuck yesterday.

• 30:01Charles Liu?

  Okay.

• 30:02Neil deGrasse Tyson?

  That

• 30:04Neil deGrasse Tyson?

  there's common sense and there's black people's sense. Black sense.

• 30:10Neil deGrasse Tyson?

  There's common sense and there's black sense. And so as an adult, if you're gonna say, sit on this train and go down this icy tube at 199 miles an hour, we're gonna just say no.

• 30:24Chuck Nice?

  Yeah, my answer is, if you tell me to go down a tube headfirst at 100 plus miles an hour, my answer is, why don't you just shoot me? I'm here.

• 30:35Chuck Nice?

  Why am I gonna do the work for you? Why am I doing the work for you? You wanna kill me? Kill me. I'm right here. Go ahead, do it. Do it, I'm right here. I'm right here.

• 30:46Charles Liu?

  I've only got one good arm.

• 30:51Charles Liu?

  I don't have the sense, I'm sorry, but I'm really glad in that instance I didn't. Because going down that hill, basically ice, on basically a sheet of plastic, at a gazillion miles an hour, was one of the most fun and exhilarating and awesome things going on. And there are other people, many of them kids, but also some adults going by me, some of them faster, some of them slower, we're kind of, some of them piled up at the end of the hill. It was so much fun.

• 31:17Neil deGrasse Tyson?

  Charles, you know who gets to say that? The people who didn't die.

• 31:21Charles Liu?

  There is a survivor bias, I admit, I admit.

• 31:25Gary O'Reilly?

  Charles, just, just, just to tap the brakes, just to tap the brakes, pun intended on this, for luge and the skeleton, they don't have any. There's no brakes on the luge or the skeleton, so there's, there's the chance of an impact, which is not my best thought.

• 31:41Charles Liu?

  We shouldn't understate the danger. Every year, professional luges are killed, professional skeletoners and bobsledders are, you know, they die from the sport.

• 31:50Chuck Nice?

  You know what's funny? Wait, I'm so glad you said that, Charles, because it's the only sport where they don't show you when it goes wrong. NASCAR, Formula One, things go wrong, you see the car disintegrate, break apart, and then you see the guy crawl out of the cage. Even for years, ABC, Y, World of Sports, had a guy coming off a ski jump, and they called him the acme of defeat. You will never see anybody, like, promote.

• 32:21Chuck Nice?

  What happens when the luge goes wrong?

• 32:24Charles Liu?

  Yeah, cuz it would be ugly.

• 32:26Gary O'Reilly?

  Yep.

• 32:26Chuck Nice?

  Yeah, cuz the guy shoots out of the tube.

• 32:29Charles Liu?

  Very ugly.

• 32:30Chuck Nice?

  Yeah. They don't even ca- they don't even follow it with the camera. The guy shoots out of the tube and then the cameraman goes, oh, well.

• 32:37Gary O'Reilly?

  There are some things. There are some things. All right, let's move on and it wouldn't be the same.

• 32:44Gary O'Reilly?

  Yeah, okay, this wouldn't be the same with a sports edition grab bag if we didn't have Via Letter and Mum Izzy. Hi, Via Letter and Mum Izzy. Great to see you. Okay. Hello. She, she has now dubbed herself as Astrophysicist.

• 32:59Chuck Nice?

  Astrophysicist.

• 33:00Gary O'Reilly?

  Good choice. Nice.

• 33:02Chuck Nice?

  Isn't she like eighteen by now? Hasn't she been asking questions for like twenty years?

• 33:06Gary O'Reilly?

  Thir- thirteen and one half.

• 33:08Chuck Nice?

  Thirteen and a half, okay, fine. Yeah. I, I, I hope we're not being capless and one day we find out that Via Letter is like a forty-three-year-old dude.

• 33:17Chuck Nice?

  Hello, Neil. Hello, Charles, Gary. My name is Via Letter and I have a question. All right, what do you got?

• 33:26Gary O'Reilly?

  What are some of the craziest sports, past or present, ever to be included in the Winter Olympics? I can't imagine there was throwing the axe while skating on ice, but that sounds like it should have been back in the day. I, I will enter one in, one, one, one sport in here. The ninety-meter ski jump. I am going up a really, really high tower. I am icing down a ski slope and jumping and trying to fly. Now, if that isn't crazy, then...

• 33:56Chuck Nice?

  No, isn't she talking about events that are no longer there? Or just, are we picking crazy events that they've got now?

• 34:03Gary O'Reilly?

  Past or present.

• 34:04Chuck Nice?

  Right, so, so, so, Charles, are there defunct sports in the Winter Olympics as there are in the Summer Olympics? Like, they don't have to tug a bore anymore? Or the, or the rope climb?

• 34:14Charles Liu?

  Right.

• 34:15Chuck Nice?

  You know?

• 34:16Charles Liu?

  I, after, you know, we did this kind of question for the Summer Olympics in a previous episode. After that, I went and took a look at the previous sports because I just found it so fascinating. And here is the one that I found for Winter Olympics, which I think is the wildest and most interesting one. It's called mountain military patrol.

• 34:38Charles Liu?

  In the nineteen twenty-four Winter Olympic Games, there was a sport called Military Patrol, where four military officers, one officer, one non-commissioned, and two privates, carrying backpacks totaling at least fifty pounds, and carrying rifles, except for the officer who carried a pistol. Uh, the officer carries a pistol. They, yeah, they had to...

• 35:01Neil deGrasse Tyson?

  And no backpack?

• 35:03Charles Liu?

  Right.

• 35:04Neil deGrasse Tyson?

  And he's got a snowmobile, but other than that...

• 35:07Charles Liu?

  The four of them together had to climb at least three thousand feet in elevation on cross-country skis going at least fifteen miles. And then, once they got there, shoot, and do target practice.

• 35:24Chuck Nice?

  Okay, that sounds to me just like a way that America found to invade another country.

• 35:31Charles Liu?

  But this is French, and this is Swiss. This is European, yeah, this is the Winter Olympics.

• 35:36Gary O'Reilly?

  Oh, so this would have been, so this would have involved the officers sitting at a table while the privates practiced their shooting, and he drank cognac while eating.

• 35:45Charles Liu?

  I couldn't tell you, but apparently this was a sport.

• 35:49Neil deGrasse Tyson?

  Was that a one-time appearance?

• 35:52Charles Liu?

  Uh, it showed up again as a demonstration sport several times later. But it has been discontinued since about nineteen, if I remember, forty-eight was the last time it was a demonstration. But imagine that, a sport where you have a team of military officers skiing, and then climbing, and then shooting at various times, while all carrying heavy backpacks. That is a sport.

• 36:16Neil deGrasse Tyson?

  So that became the cross-country pentathlon, I guess. What's the one where they...

• 36:21Charles Liu?

  Well, biathlon today.

• 36:23Neil deGrasse Tyson?

  Oh, the biathlon.

• 36:25Charles Liu?

  It's a biathlon where you ski, shoot, ski, shoot, ski, shoot. But nowadays, those rifles are very light caliber. They're heavy, yes, but much less heavy than a true machine gun or a weapon that actually a military person used to use. And now, it's really a streamlined sport that combines the skill of shooting, target shooting, not actually military shooting.

• 36:51Neil deGrasse Tyson?

  It sounds like, you know, the grandpa on the porch. "Back in my day, the rifles were heavier, and we had to climb uphill both ways and then shoot."

• 37:00Charles Liu?

  Uh, yeah, maybe. I, well, I'll say this...

• 37:03Chuck Nice?

  And we shot at each other.

• 37:06Charles Liu?

  I have been. You should see how many bullet holes I have right now from the Olympics. I have, I have been very fortunate in my life, never have to fire any kind of weapon uh in anger. And so I cannot speak for what is easier or more difficult, but I can give you the numbers.

• 37:22Chuck Nice?

  Qualifier, Charles, what a qualifier.

• 37:24Neil deGrasse Tyson?

  I know, right?

• 37:24Chuck Nice?

  In anger, I shot the guy after I calmed down.

• 37:30Charles Liu?

  No, no, don't, don't dredge up that memory.

• 37:33Neil deGrasse Tyson?

  That was a, I don't even want to probe that qualifier, Chuck. Let, let, let that one go.

• 37:39Gary O'Reilly?

  All right, do we have time?

• 37:40Neil deGrasse Tyson?

  Yeah, yeah, Stewart, yeah, yeah.

• 37:41Gary O'Reilly?

  Charles Maco, hallo's Dr. Tyson and Lou, um, what impact Chuck, Chuck and I, we're not here. Uh, what impacts will climate change have on Winter Olympics throughout the rest of the century? Of course, some sports are already played indoors like skating and curling, but might we see an end to sports that require outdoor cold temperatures?

• 37:59Charles Liu?

  You'll see an end to, to them in different parts of the world where they traditionally existed. Uh, remember with global warming, you're like a hundred million atomic bombs worth of extra energy floating around in the atmosphere at any given time, right? For every degree change in Celsius. There's going to be a lot of motion. So some parts that were traditionally cold will get warm. And some parts that are traditionally warm will get colder, right? So in Switzerland, for example, or in parts of France, the famous uh ski areas, Chamonix, you know, places like that, they're already having real trouble getting enough snow to have a decent recreational ski season. So their sport seasons have been severely curtailed already.

• 38:41Charles Liu?

  And that's true. Other places where currently nobody goes to though, maybe certain areas of mountain tops, certain places where polar vortices coming out from different parts of the Arctic will create new flows of cold. Those areas might get much more snow and much more ice than they do today.

• 38:59Neil deGrasse Tyson?

  Yeah, but that, but no one has put a ski slope there yet. So that this would change, change the business landscape.

• 39:04Charles Liu?

  The entire landscape will change. A decade from now, two decades from now, people will be skiing in parts of the world where there never were any slopes. And places where there used to be skiing all the time are going to be struggling, making snow all the time, hoping for a good season, uh, and maybe even changing their economic systems completely. So the idea is that you're gonna have a world where the sports will still continue, but they'll be in completely different places, places where there are no ski slopes or winter resorts today, they will be there, and in other places where there were for decades, maybe even centuries, those places will struggle. That's what's gonna happen.

• 39:41Chuck Nice?

  Welcome to the 2050 Olympics of Winter here in Fiji.

• 39:49Charles Liu?

  It's gonna be weird. It's gonna be strange. We all have to adapt.

• 39:53Neil deGrasse Tyson?

  All right, Gary, give me another one.

• 39:54Gary O'Reilly?

  By the time, by the time, by this time the show goes out, we'll have done our ice and snow show, and we have a great guest, Dr. Peter Veals, who makes artificial snow. So maybe he is on the, he is the vanguard of a boom industry.

• 40:09Neil deGrasse Tyson?

  Yes, yes.

• 40:10Gary O'Reilly?

  Making powder snow. We shall see. Right, one more question.

• 40:13Neil deGrasse Tyson?

  One more, Gary, see if we can get it.

• 40:16Gary O'Reilly?

  All right. Anna C. Hickman, hello all. I have a question about Paralympic athletes and a future time somewhere when I am probably already dead. As a wheelchair user, I am an avid follower and participant in adaptive sports, and I know sometimes there is chatter about how an adaptive athlete has some advantage because they use specialized equipment when compared to regular athletes. If we as a human race got to the point where we had outposts in space and there was interplanetary Olympics, would an athlete who already knows how to navigate in a compromised body when compared to able-bodied athletes have an advantage in competition? Would the roles potentially be reversed and the power athlete be the one with the perceived advantage?

• 40:57Charles Liu?

  I would totally see that as a real possibility. Yeah.

• 41:00Neil deGrasse Tyson?

  Yeah, as would I. Yeah, I think, I think what we, what we declare to be an advantage or not, it's according to some norm that someone establishes, but you can imagine constructing sports where whoever was previously advantaged now becomes disadvantaged. I mean, you could, you can come up, I mean, look at how random sports are anyway. Take this ball and put it in a, in a hole, or in a hoop, or jump, or crawl, or this, curling.

• 41:37Neil deGrasse Tyson?

  So, so I welcome your, your, your follow-up on this, Charles, but it seems to me that we've created a world where parat-

• 41:50Neil deGrasse Tyson?

  Paraathletes are trying to do what non-paraathletes, what has been invented and styled for paraathletes. Imagine a whole set of competitions designed specifically for paraathletes. And then, then they have the advantage, right? So, so, so a new world, like you said, if you go into space, you go into zero G or low G, all, all the dynamics changes about who's good and who's not good at some sport. So, that's a, that's a, that's a fascinating new world. I think it's underexplored in people's creative ways.

• 42:28Charles Liu?

  I have very little to add to that, Neil. I think you're a hundred percent right. And just our understanding of what is able-bodied and what is a compromised body varies with every environment that we go into. New sports are invented all the time. A lot of times we forget, right? We were just talking about military patrol, which is no longer being done anymore. But that was a real sport in the 1920s, right?

• 42:51Chuck Nice?

  Or an advertisement for officers' training.

• 42:55Charles Liu?

  You don't have to carry the rifle, right? The, the, we should always be adapting to new places and always looking at human beings as whole individuals. And when we see what an environment provides for sport and recreation, we should leap on it and find it and use it and make it our own, regardless of who's out there, and turn it into fun. That's what the Olympics should be in the end, right? Fun.

• 43:21Chuck Nice?

  And the only difference is, going back to what Neil said about the fact that Paralympics, I mean, paraathletes have to do what, you know, able-bodied athletes do. If it were the other way around, take the able-bodied athlete and make them compete in the same Paralympics, they lose every event. Like the gentleman that we had on that shoots, uh, uh,

• 43:52Charles Liu?

  Archery.

• 43:53Chuck Nice?

  Who's the archer? Who does it with his feet? Let any archer try to do that. And they lose.

• 44:01Neil deGrasse Tyson?

  Yeah, Matt Stutzman was the guy, right?

• 44:03Chuck Nice?

  That's it, Matt Stutzman.

• 44:04Neil deGrasse Tyson?

  One of my favorite episodes. Yeah, yeah, yeah. All right, Charles Lu, fellow astrophysicist, geek in chief. And wherever I am on the geek spectrum, he is beyond that.

• 44:18Charles Liu?

  You are too kind, sir.

• 44:19Neil deGrasse Tyson?

  All right.

• 44:20Chuck Nice?

  Only on this show is that a compliment.

• 44:25Chuck Nice?

  There you go.

• 44:27Charles Liu?

  Not only.

• 44:28Neil deGrasse Tyson?

  All right, Chuck. All right, Gary. This has been StarTalk Sports in a Cosmic Aquarius Grab Bag, all about winter sports. Neil deGrasse Tyson here. Keep looking up.