Over the last 400 million years, the day has grown longer by two full hours thanks to a slowing of the rotation of the Earth on its axis. While it will be a very long time before it stops spinning altogether, it never hurts to plan. Listen to Chuck and Josh discuss what a still Earth would look like.
Male Speaker: Brought to you by Toyota. Let's go places.
Female Speaker: Welcome to Stuff You Should Know from howstuffworks.com
Josh: Hey, and welcome to the podcast. I'm Josh Clark. There's chipper and cheery Chuck "Chuckers" Bryant right across from me. How are you doing?
Chuck: I'm good, man. I'm about to go get that jar of moonshine from my cubicle. And we've never done a show where we've just drank moonshine the whole time.
Chuck: I think we should. What better day?
Josh: I'll have a sip.
Chuck: I don't think it's at my desk anymore. I think it's at home.
Josh: Oh, really?
Josh: Do you have beers still?
Chuck: There may be some over there. I don't know.
Josh: What about beer?
Chuck: Well there's a case of beer that some other dude sent me. Like not - it wasn't show related, but it's been sitting there for like a year.
Chuck: Shiner Bock.
Josh: Oh, I got some too.
Chuck: And then there's a couple of beers from like England, and then there may be some moonshine.
Chuck: So, let's just get drunk.
Josh: Okay, so you're feeling good?
Chuck: Yeah. I'm just kidding folks. We're not going to do that.
Josh: Is what you're saying.
Chuck: What's your intro?
Josh: Well, my intro is - you've already poo pooed it.
Chuck: Yeah, I feel kind of bad about that.
Josh: Oh, don't feel bad. It's pretty much par for the course, buddy.
Chuck: All right.
Josh: Are you ready?
Josh: Many, many years ago, roughly around 4.8 billion years ago, the Earth really started to form. It came together from a bunch of dust and rocks and other dust.
Chuck: So says you.
Josh: Because - right. Because the universe was spinning, right? And all these particles were spinning, and as they came together to form an accretion, from an accretion disk. It formed the Earth. And all -
Chuck: And other planets obviously.
Josh: Right. And all that spin, thanks to the laws of thermodynamics, one of them, continued to spin and actually accumulated. And so the Earth just is spinning. That's why it's spinning because it's always been spinning and all of its particles that make it up have been spinning. So, it's spinning because of the Conservation of Angular Momentum, right.
Chuck: And Newton's First Law of Motion of course.
Josh: That's what it was, not thermodynamics.
Chuck: Oh, is that what you were going for?
Josh: It's the Law of Motion, which is what?
Chuck: If an object - an object in motion will remain in that state of motion unless, basically, someone comes along and puts the brakes on it.
Chuck: Unless something acts upon it.
Chuck: To stop that.
Josh: And in the vacuum of space, there's nothing to act upon it to slow the Earth down, so it's going to just keep going. And actually the Earth has slowed in its older age. 400 million years ago, a day lasted 22 hours.
Chuck: Yeah, it's been slowing consistently over time, right?
Josh: Yeah, but it's going to take a while to stop.
Josh: I think in 400 million years, in the future, they think the day will be 26 hours. So two years slowing by - or two hours a day over 400 million years, it's not quick.
Chuck: Well, in 400 million years, is there going to be any Earth?
Josh: I don't know. That's such a good question. What would we look like?
Chuck: I don't think there's going to be humans in 400 million years. That's my guess.
Josh: So, the Earth is slowing. We understand why it's spinning. We understand that it is slowing down, but what happens if somebody just comes along and just stops it automatically? Like just stopped, beep, stopped.
Chuck: Well -
Josh: And by the way Jerry, that wasn't an edit.
Chuck: Yeah, that's our signal when we beep. That is a call out to Jerry. So, we're moving very fast. Like faster than the speed of sound even though it doesn't feel like it.
Chuck: So if someone stopped it, those same things that would happen if you just stopped your car all of a sudden, or a train stopped all of a sudden, would happen here on Earth except it would be much more drastic because we're spinning much faster.
Josh: Right. We're spinning in an easterly direction at about 1,000 miles an hour along the equator. So yeah, if all of a sudden you stopped the Earth, everything that's unattached to the Earth would keep going eastward at about 1,000 miles per hour.
Chuck: Mass - instantly dead, massive flooding, you name it.
Josh: Yeah. The wind, the shockwaves, buildings, everything would just go, "phew." And you said something that I find kinda interesting. Like when I started to research the Earth's rotation, it's one of those things where I just assume I know what I'm talking about, and the more I looked into it, I was like, "Oh, yeah, there's a lot of little stuff here."
Josh: Like questions like why don't we feel that fact that we're moving through space at about 1,000 miles an hour? And well, I found the answer. Because the Earth moves at a constant speed, a constant rate of rotation, there's no acceleration or deceleration which we would feel if that happened, right?
Chuck: Yeah, why don't we spin off the Earth?
Josh: Do you know why?
Chuck: I do.
Josh: Okay, let's hear it.
Chuck: Because of gravity and the gravitational pull. We want to spin off of the Earth. That's in there, but the force of gravity or the force that wants to spin us off the Earth is 0.3 percent the force of gravity.
Josh: Right, centripetal force.
Chuck: Way much more gravity going on than there is the other, so.
Josh: And I found that if the Earth rotated at a rate of 80 minutes, right, it spun around on its axis one full time, so one day was 80 minutes long, that would be fast enough to overcome the force of gravity. And we would be thrown off into space.
Josh: But we're not going anywhere because the Earth is never going to start speeding up like that. That's just crazy talk.
Chuck: No, and it's not going to stop spinning either, any time soon, but we can still have fun with this topic.
Josh: So, say that we were existing right now, as the Earth was really starting to slow down. It's making its last turn.
Chuck: Yeah, so it did it gradually like Superman style.
Josh: Right. And then the ecosystems were intact. Everything was generally intact the moment the Earth stopped spinning.
Chuck: The day the Earth stood still.
Josh: Exactly. There would be some really interesting things that happened. Like a lot of our - the geography of this planet, I took for granted until I read this article which really opened my eyes.
Josh: So, what are some of the things that would happen if the Earth just stopped spinning?
Chuck: Well seismologists think that it would set off a massive chain of super earthquakes because they suspect that the rotation of the Earth plays a big role in the movement of the tectonic plates. So, they, seismologists, think that we would all be dead because of massive, massive earthquakes.
Josh: Okay, we'd probably be dead for a lot more reasons which we can explore, but, yes, earthquakes would be a big one.
Chuck: How would you die first basically?
Josh: Yeah, because think about it. That spinning Earth - the centripetal force of the Earth is so strong that it basically keeps the oceans in place. It creates a bulge around the equator. The Earth is not a perfect sphere. It's bulged at the middle. And that's because of its spin. And that bulge actually brings the world's oceans toward the equator. In the Southern Hemisphere, they move north. In the Northern Hemisphere, they move south. But it's being pulled toward the middle of the Earth, the Earth's spare tire. So, if it stops spinning, all of a sudden the world's oceans would go toward the poles.
Chuck: Yeah, like quickly.
Josh: It would be pretty cool to see.
Chuck: Guess - not if you're at the poles.
Josh: Did you see a map of what it would look like?
Chuck: Yeah, basically like a super continent in the center on both sides of the equator.
Josh: Yeah, like all the way around the globe.
Chuck: And two big oceans, one on top and one on the bottom.
Josh: Yeah, and the one on the top at the Arctic, would actually be about 1,000 meters deeper, not because there'd be more water there, but the Antarctic Basin is bigger, deeper -
Chuck: Yeah, that makes sense.
Josh: So, the water would be shallower by comparison.
Chuck: Yeah, more displacement.
Josh: But, yeah, I was looking - so Chicago would be just underneath the north shore of the Northern Hemisphere's ocean.
Josh: And from that point down, the United States would be largely intact. All the way into the Caribbean south, it would just be land. It's pretty neat.
Chuck: That is pretty neat.
Josh: It was a neat looking map. I love freaky, weird maps.
Chuck: Like the early maps?
Josh: Those were a little weird. There's a blog called, "Unusual Maps," I think.
Chuck: Freaky, weird maps?
Josh: "Odd Maps," I can't remember what it's called, but it's just this blog about strange maps.
Chuck: Oh, cool.
Josh: It's pretty neat.
Chuck: I used to collect maps.
Josh: Oh, yeah?
Chuck: Yeah. I mean, I didn't have a ton. I had like 15 or 16 like cool map posters.
Chuck: I still have a few of them, but I think they went the way of the dodo in my house.
Josh: Were they like scholastic foldouts?
Chuck: No, some were like a Civil War map or the Earth at this point map or, you know, very - none of them were just straight up. I think I had one straight up map. So, what else would happen? One thing that would happen is the - and Robert Lamb wrote this didn't he? No?
Josh: A guy named Jonathon Adebury.
Chuck: Oh, that's right, Adebury. Adebury, good job. He says that it will take a whole year to pull off what the Earth does in a day.
Chuck: Which makes sense. So, one part of the world would be a blazing, scorching desert, and then one part of the Earth would be a barren, frozen wasteland.
Josh: Half a year, half and half.
Chuck: For half the year.
Josh: And that's because since the Earth rotates on its axis in about 24 hours - a little under I think.
Josh: If it stopped doing that, it would still move around the sun. It just wouldn't spin on its axis. So, I figured this out. If you're having trouble visualizing it like I did, put your thumb in front of your face, out a little bit, so that your thumbnail's facing you. And then pretend that the sun in between you and your thumb. And your thumb is the Earth.
Chuck: Yeah, okay.
Josh: And you just rotate it around so that your thumbnail's facing you all the time, but it's going around the sun. And you'll see that at any given point, this part of the Earth is facing a different part of the sun.
Chuck: The thumbnail?
Josh: So there would be seasons, but there'd be four seasons. And they'd be very different. The line demarcating them would be really different, and when you went from winter to summer eventually, you would have nothing but sunlight and then nothing but dark depending on the season.
Chuck: Yeah, the temperature swing would be huge.
Chuck: So, what means is we'd probably have a really difficult time propagating with husbandry, in general.
Josh: And you don't mean sex. You're talking with plants and animals.
Chuck: I'm not sure what you mean there.
Josh: Propagating with husbandry sounded like a euphemism.
Chuck: Yeah. No, just farming, animals, all of that would be more difficult, if not impossible to grow crops for - or maybe you grow them during the sunny parts of the year, what you can grow, and then store. But, we'd be in bad shape.
Josh: I would think that we would be in very bad shape.
Chuck: As far as that goes, botanically speaking.
Josh: But, we are pretty quick witted species, so we could possibly overcome it technologically.
Josh: I'll bet we'd have really good sunglasses.
Chuck: Yeah. Yeah, that's true, and coats.
Josh: What else would happen, anything?
Chuck: Well, the magnetic field - well, gravity. I got something on gravity here. Gravity would be changed which is not in the article. But, it would change significantly if it stopped spinning because centripetal force, of course - which we were talking about - contributes to that gravitational field, and it wouldn't exist any longer. So, the gravitational field would be strongest at the poles instead of at the equator, and who knows what that would do.
Josh: You'd just be a lot heavier at the poles, right?
Chuck: You think?
Josh: We would also lose a very interesting thing called the Coriolis effect.
Chuck: Yeah, my favorite.
Josh: Which you know, supposedly with the Coriolis effect, if you're in the Northern Hemisphere, if you flush the toilet, the water goes down the drain clockwise and in the Northern Hemisphere counterclockwise.
Josh: That's not true. It's all plumbing. It's all the design of the drain. The Coriolis effect is there -
Chuck: Oh, really? That has nothing to do with what part of the Earth you're in?
Josh: No, It has nothing to do with like the drain. It's supposedly, the Coriolis effect, the fact the Earth is spinning faster at the equator than it is at the poles, has long been tasked as a reason for whirlpools. They're saying, no, it's probably - if you're talking about a drain, it's the angle of the drain. It's the design of the drain. It's the water rushing in when you flush the toilet. It has nothing - it's an old wives tale, but there is a Coriolis effect. It's just not quite as interesting. Basically, it says that if you leave the North Pole and fly toward the equator, toward a certain mark of the equator, if you go in a straight line, you're going to miss your mark because the Earth is spinning, and it's spinning faster at the equator than it is at the pole. So that's the Coriolis effect.
Chuck: It's a curve. It would look like a curve, right?
Josh: Yeah, you have to basically correct longitudinally.
Josh: To hit your target, like you just can't fly in a straight line from the North Pole to the equator if you're trying to get to a certain spot.
Josh: That's the Coriolis effect.
Josh: I guess. Unless I'm missing something, it seems kind of basic.
Chuck: Yeah, it's kind of basic once you wrap your head around it. There are some things are slowing the Earth down, like you said. The days are longer now than they used to be?
Chuck: They used to be what, 22 hours you said?
Josh: 400 million years ago, yeah.
Chuck: Okay. So, we are slowing down. There is tidal friction, and the tide drags 2.3 milliseconds on each century, every 100 years.
Chuck: So, that's pretty slow.
Josh: Right, but it adds up over time, wetwilly.
Chuck: Sure. Of course it does. Weather can affect it too. Winds can actually slow it down. Earthquakes can redistribute the mass and actually speed up. Didn't it speed up in the earthquake in Japan?
Josh: Yeah, I think by 1.8 microseconds. The Earth's day, its solar day, was accelerated because that earthquake was so massive.
Chuck: Nothing we could notice.
Chuck: What about magnetic field though? That's what I don't fully get.
Josh: So, with the magnetic field, we're not quite sure why Earth, or how Earth has a magnetic field, but the prevailing theory is that because of this Coriolis effect in the center of the Earth, whirlpools are created of molten iron. And as this molten iron kind of moves around and forms these whirlpools, it actually generates an electrical field, an electrical current which in turn generates a magnetic field. So, we have this magnetic field. We think that's how we have it, but we have also long suspected that the magnetic field protects the Earth from solar winds which are positively charged ions from the sun that travel about a million miles an hour off of the sun towards us.
Josh: And they are about a million degrees Celsius. And we've long thought that it protected our atmosphere from being stripped of the ions that we need. Then we started looking at other planets that don't have any magnetic field because I think it's just the Earth and the sun, in our solar system, are the only ones with magnetic fields.
Josh: And we've found that they lose ions at about the same rate that our atmosphere loses ions, so we don't know what the magnetic field's doing. But I did come across this one interesting fact. We lose about a ton of atmosphere a day.
Josh: Yep, and mostly in the form of water vapor.
Josh: So, the Earth is drying out very slowly.
Chuck: Boy, so we're slowing down. We're drying out. In 400 million years, we'll all be toast.
Josh: Yeah, that's pretty much the long and short of this.
Chuck: And what - we did a podcast on what would the Earth look like at different intervals in the future.
Josh: Right, yeah.
Chuck: And I think we eventually landed on, ultimately destruction and -
Josh: If we're even here any longer.
Chuck: Yeah, exactly.
Josh: We'll use the Earth up is probably where we landed.
Chuck: Yeah, I think you're right.
Josh: Well, good going Chuck. Let's hear it for Chuck everybody. Do you have anything else?
Chuck: I do not, sir.
Josh: If you want to learn more about the Earth standing still, go to howstuffworks.com and type in Earth, and it will bring up some pretty cool articles, in probably an entire channel. Just earth science just fascinates me.
Chuck: Yeah me too.
Josh: I said search bar somewhere in there which means it's time for listener mail.
Chuck: You know you called out for, "How we helped you in your life" emails?
Chuck: We got one from Rachael in Portland.
Josh: Oh, good. Let's hear it.
Chuck: Port-land. "You guys have helped me through some of the toughest times of my life." I've shortened it a bit. "In August I moved from a small town in Mississippi to attend the University of Portland in Oregon. Transition was rough. Needless to say, I did not handle it well. I started smoking again. I had trouble focusing on and attending classes, and I could tell that I wasn't settling well or making friends. On top of all that, my three year relationship with my high school sweetheart fell apart because of the distance and the stress of us both beginning university. I began to relapse into depression, something I've struggled with, off and on, for five years."
Chuck: "I found myself unable to listen to music even because every song I heard made me so sad." Isn't that awful?
Chuck: Remember those heartbreak days when you just sit around and listen to the radio and cry? "I downloaded your podcast to listen to as I walked to and from classes and while I did homework. I did notice at first that every time your podcast was on, it made me laugh. I'd feel a little bit better. About halfway through the semester, I found the courage to seek help and visit the campus health center for therapy and anti-depressants. I am now in my second semester of college with a 3.94 GPA."
Chuck: "I have a few great friends, and I'm even dating someone new."
Chuck: "I love my school, and I love the city of Portland. I feel as if your podcast served an integral part of helping me make the transition from home to here. I've learned and laughed with ya'll. And now and then a southern drawl will sneak into one of your voices and make me nostalgic for the South. This may sound silly, but I feel that I've come to know you guys. I really wanted to thank you for helping me through such a hard time." Rachael, 18 in Portland.
Josh: Thanks Rachael. That's awesome. I'm glad to hear you're doing better.
Chuck: Yeah, I had a rough first few weeks of college. I think a lot of people do. And I think my advice is to just stick it out and before you know it, you're going to be loving it.
Josh: Yeah, I remember my parents telling me that when I went off to camp.
Chuck: Oh, yeah? Did you even like camp?
Josh: I did not like camp, no.
Chuck: Did you like going off to college?
Josh: Yeah, I was fine.
Chuck: You were probably ready for that, huh?
Chuck: Yeah, I was - I freaked out because at the last minute I tried to change to go to Georgia Tech because my brother was there. And I was basically scared. I was like, "I just want to go to school with my brother." And it didn't - it was too late to get the application in, so I was like, "All right, I guess I'm going to Georgia by myself."
Chuck: And it ended up being the greatest thing ever, of course.
Josh: I'm glad. I'm glad you stuck it out.
Chuck: You know the rest of the story.
Josh: Yeah, it is true. I mean, just hanging in there and being brave even when it feels like that's the worst thing do. Often - it's often the best thing to do.
Chuck: And six years later, I had a college diploma and a lot of friends for life.
Josh: Right. That's good Chuckers. Let's see. If you have a great story about solar wind, or how we helped you, or college, or whatever, we want to hear about it. You can find us on twitter, right? SYSKPodcast. I feel like a lot of you aren't getting that. SYSKPodcast. It's a great twitter feed.
Chuck: Yeah, Josh is the twitter master.
Josh: We have a great facebook page that Chuck helms, facebook.com/stuffyoushouldknow.
Josh: People love that. You can send us an email which is fine. That's firstname.lastname@example.org. And everybody, seriously, stop what you're doing right now. Go to the home of Josh and Chuck on the web. It's our very own website. It's fun. It's called stuffyoushouldknow.com.
Female Speaker: For more on this and thousands of other topics, visit howstuffworks.com.
Male Speaker: Brought to you by Toyota. Let's go places.
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Duration: 21 minutes