If the Earth were to quit revolving...

[tom1499]

I think whats more important is the gravity increase from the lack of centrifugal (please don't start arguing about that too) force pulling you up would mean that all those dieters on the equator would be heavier again. A bit. A very minuscule bit.

[KvickFlygarn87]

I would never again have to use a time converter to see when a rocket is launched in Swedish time.

[NASAFanboy]

First of all, nothing would likely happen. The Earth stops rotating. And so do we. When you jump on a jet plane, do you get blasted off the rear end of the airplane and out into the sky? No. (And yes, I've done this many, many times). The same principle applies to Earth, except we don't live on the surface of a Jet Plane, and jet planes don't have little bubbles of atmospheres that they cart around. Our planet could just stop rotating right now, and noone would notice for a short time.

However, the implications shortly after would be a little more...severe. The side facing the sun would become desert, while the side facing away becomes cold as heck. Civilization would then be restricted to a large swath of land between the two "equlatoral poles", that wouldn't be that bad (Hell, I'm even willing to bet that things like the United States, the UN, and China, plus most of the global structure will survive. Can't say much about the smaller nations that inhabit the new habitable zone, though) . That's about it. Not even the ISS will feel a thing.

The atmosphere is a "intertia damper". Oh, and when you jump, you don't reach orbit either.

[brdavis]

First of all, nothing would likely happen… When you jump on a jet plane, do you get blasted off the rear end of the airplane and out into the sky? No.

When you are in a car and the car hits a wall, do you just happily stay in your seat? No.

Inertia. It's reality. Even if you don't think it is

The side facing the sun would become desert, while the side facing away becomes cold as heck.

You do realize if the Earth stops rotating, it would still have days and nights? Admittedly rather long ones… I'm not even sure exactly what you'd get on a tidally locked Earth, with one side in perpetual sunlight. Some simulations have been done, and for even very moderate atmospheres you can redistribute heat surprisingly well. Yeah, not 'comfortably'… but at least the Larry Niven "the atmosphere freezes out on the backside" seems to have been fairly discredited.

The atmosphere is a "intertia damper".

No. Not really.

[Sternface]

First of all, nothing would likely happen. The Earth stops rotating. And so do we. When you jump on a jet plane, do you get blasted off the rear end of the airplane and out into the sky? No.

A more apt analogy would be if you were standing in the isle of a jet traveling at 1,600 km/h, which suddenly slammed head-first into a vertical Himalayan rock-face, like the side of K2 or Everest. Do you get blasted off the rear end of the plane and out into the sky? You do - well, very very small chunks of you that manage to get past the disintegrating fuselage.

Inertia can quickly rain on your velocity parade, like it does with this jet:

That jet was going 800km/h. Double that, and see what happens when you jump inside the cockpit 1 second before impact (aka, 1,600km/h deceleration, the same one would experience if the world stopped instantly.)

One could say that the concrete wall destroys the plane. One could also say that the plane's change in momentum responding to an almost instantaneous 800km/h deceleration destroyed the plane. Same thing.

But with the Earth scenario, I highly doubt that your feet will provide enough traction to fully transfer the force of deceleration. More likely, you will lose your balance, fly for a fraction of a second at 1600km/h, and then be ground to a pulp upon landing. Possibly compressed and superheated by the atmosphere, which will be working to resist your deceleration.

[KerbMav]

As of now you are all talking about different situations with different assumptions. Funny to read though.

[Xetalim]

I miss a thing.

If earth violently stops moving, things on one half of the earth would be thrown up, things on the opposite side would be crushed into the earth.

If the empire state building would be on the second half, it would probably be crushed by the extreme G forces you would get.

(My opinion, i am not good at science-ish things.)

EDIT:I was talking about when the earth stops rotating around the sun, sorry)

Edited November 27, 2013 by Xetalim

[lajoswinkler]

God I love those "it is impossible" people. This is a hypothetical scenario, folks. Of course it is impossible for Earth to suddenly stop rotating.

But if it did come to a halt, its surface would turn into a huge mess. First everything not attached firmly to the ground (pretty much everything we've built, together with forests etc.) would be ripped from the ground at huge speeds and continue on a tangential trajectory. Angular speed of a point on equator is 1670 km/h. Speeds decrease by the cosine of the angle of the latitude. If your latitude is 80°, the speed would be cos (80°)*1670 = 290 km/h.

You can imagine the destruction would be incredible.

On top of this, we have to add the atmosphere. It would continue rotating, so its speed relative to the ground would be enough to errode a whole lot of surface features.

Hydrosphere would turn into huge global tsunami.

Last, but not the least important, would be the lithosphere. It would crumble, possibly ripping and pulverizing while being launched sideways. It would contaminate the atmosphere with dust and lava.

Basically the planet would be one bowl of mashed potatoes, only with magma exposed, thick cover of Venus-like clouds and without potatoes.

After a while, the oceans would return and flood the poles. Remember, the centrifugal force is making the hydrosphere bulge on equator, so without rotating, they would redistribute equally.

It would be worse than a huge asteroid impact.

[Nibb31]

But if it did come to a halt, its surface would turn into a huge mess.

Doesn't that depend on how long it takes to stop turning?

Any kinetic damage would depend on the amount of deceleration. If the the process was spread out over several years, then the actual trauma from the deceleration might be bearable. But of course, we would have other problems.

Any coriolis effects would disappear, meaning that we would lose most of our ocean and atmospheric currents, like the Gulf Stream or Jet Stream. The climate would be screwed, with super hot summer/days and super cold winter/nights. That would probably cause cataclysmic storms and winds around the terminator.

If it took millions of years, then some species might be able to adapt to the new environment, but if it's oonly to happen over a few years or centuries, then the wildly varying temperatures would probably cause the extinction of most species. Some microbial lifeforms might survive though, so all is not lost.

I agree that it's a bit of a silly postulate and that it needs a bit more hypothetical precision, such as what causes it and how long it takes.

[lajoswinkler]

Doesn't that depend on how long it takes to stop turning?

Any kinetic damage would depend on the amount of deceleration. If the the process was spread out over several years, then the actual trauma from the deceleration might be bearable. But of course, we would have other problems.

Any coriolis effects would disappear, meaning that we would lose most of our ocean and atmospheric currents, like the Gulf Stream or Jet Stream. The climate would be screwed, with super hot summer/days and super cold winter/nights. That would probably cause cataclysmic storms and winds around the terminator.

If it took millions of years, then some species might be able to adapt to the new environment, but if it's oonly to happen over a few years or centuries, then the wildly varying temperatures would probably cause the extinction of most species. Some microbial lifeforms might survive though, so all is not lost.

I agree that it's a bit of a silly postulate and that it needs a bit more hypothetical precision, such as what causes it and how long it takes.

That's why I was describing a scenario where the halt is sudden, abrupt, impulse-like.

I think that even if it's spread during few years, the tectonic plates would suffer greatly. Lots of earthquakes, probably. We're talking about huge amounts of energy and stress inside.

OP was precise:

If we were to visualize the sudden-stop theory, what do you think would most likely occur?

(though this has nothing to do with theories or even hypotheses, because it's a scenario, not an explanation)

[Skyler4856]

As a consequence of the sudden deceleration the earth's magnetic field would shut off.

[Camacha]

All of this. Which is why I called it a dumb question earlier.

Questions like this are never dumb. It is a cardinal mistake to call them that. They are at worst ill-defined. Instead of namecalling, it would be best to simply obtain a better definition.

Wondering about the realistic impact of impossible or improbable events is exactly what got science and humanity as far as it is. Thought experiments are important, both because they make otherwise dry science fun (for the real proper scientists too!) and because they nurture major breakthroughs that do not always seem to follow logically from the current state of affairs. Saying something is impossible or even dumb and refusing to think any further is one of the worst things you can do if you are scientifically inclined, curious and want to gain knowledge about anything.

Only calling good (but ill-defined) questions dumb is truly dumb. Asking questions like this is a fundamental part of science.

[Starwhip]

Well, what do you mean if the Earth stopped rotating? If it just suddenly stopped.... well, actually, why would anything happen at all? If everything stopped moving, then why would anything be destroyed? Everything would have stopped, people, buildings, etc. But if the actual "sphere" stopped, and everything else was to continue moving, the atmosphere would suddenly be moving at around 1000 mph at the equator and 0 mph at the poles. Guess what that means: Extreme Coriolis Effect. Or to put it simply: Global Hurricane. In about 10 minutes or less, the winds would start to create spin, and all the while, would rip anything out of the ground that is not very well attached, and erode cities and mountains alike. Generally, this would be a bad thing.

[Maxwell Comp]

I have a small experiment that may help illustrate an interesting idea hidden in the question. Get a helium-filled balloon on a string, them get into your car with the balloon. Hold the string so the balloon is floating without touching anything else, and then keep an eye on it while you accelerate. The question is, which way does the balloon move when you accelerate?

If my memory is correct, the balloon actually moves forward. This is because it is lighter than air, and so it will be displaced by the air due to the slight pressure change caused by the acceleration. Pressure in the back of the car will be slightly higher, so the balloon moves forward a bit into the lower-pressure air.

In light of this interesting fact, what do you think will happen to airplanes that are flying if the earth's rotation suddenly stopped?

[Bacterius]

In light of this interesting fact, what do you think will happen to airplanes that are flying if the earth's rotation suddenly stopped?

I'll just say this - it would be a memorable experience.

[kahlzun]

stuff on the equator is moving about 100 m/s, so it would move violently 'eastwards' due to inertia. Reduced immediate effects would be felt the further from the equator you were.

The atmosphere would briefly become hurricane force relative to the ground, again diminishing away from the equator.

[WestAir]

"What will happen to airplanes if the Earth suddenly stopped rotating?"

Same thing that happens to fish in the ocean. Are the fish all shot forward? Unlikely, because the ocean, as a fluid, isn't as rigid as the crust and will move along at its original velocity, slowing down due to the friction with the ocean floor. Fish will just go with the current. The same for aircraft. Air is a fluid, and it certainly won't "suddenly stop" because the chunk of mass below it does. It'll become an intense mach 1 wind all around the world, sure, but for things traveling a comfortable 320 knots inside it, they probably won't even notice a change.

Unless you're also saying the sudden deceleration affects everything but man-made objects. In which case, the oceans and air and fluids and gases have no momentum and stop immediately. This one is more interesting, because aircraft traveling eastbound will gain a sudden headwind of hundreds of knots. Aircraft traveling westbound will gain a tailwind of hundreds of knots. Private, General Aviation, and commercial aircraft would be destroyed by the stresses of high-speed flight. Super-sonic fighter jets traveling eastbound that were not already flying at high speed will avoid being forced into speeds that would cause structural failure. All other aircraft would be torn apart.

Though none of that would happen if the oceans and air were allowed to act as the fluids they were and keep their momentum during the stop.

[comicbstudeo]

define. do mountains count? if so then surely so do buildings and trees and other things.

[Dunbaratu]

God I love those "it is impossible" people. This is a hypothetical scenario, folks. Of course it is impossible for Earth to suddenly stop rotating.

No, you're completely missing the entire point of those complaints. Pay attention. What's being said is that once you say you're altering the laws of physics enough to make a thing like that possible, you then have the responsibility to go into detail about *exactly* what you mean and *exactly* what you're altering, otherwise the "what if" question cannot be answered. For example, the earth isn't solid, so are you saying just the core and mantle stop and the crust keeps its momentum? OR are you saying the crust stops too? And if the crust stops then why not the things embedded into it like buildings and roads? How are they any less a part of the crust than the stones in it are? And if the oceans aren't covered by the "earth" suddenly stopping and instead they act as independant objects sloshing on the surface of the planet then why isn't the crust treated the same way, sloshing atop the mantle? And if you want to talk about the objects on the world being subjected to a sudden force ripping them off the ground as it stops in an instant and they don't, and you want to talk about how bad that force would be, and yet you're describing a universe in which it's possible to apply an infinite force in zero time ANYWAY as that was necessary to get the earth to stop rotating in an instant, then how much of those changes to the laws of physics should be taken into account when describing what happens to those objects that get flung off?

The problem is that people try to *simultaneously* say the laws of physics are drastically different in this hypothetical scenario, AND that they're just the same as ever. Make Up Your Mind. If you want to break the laws of physics to make a hypothetical scenario that's fine, but you can't then turn around and immediately start asking what the laws of physics would do in that scenario if you haven't explicitly and carefully laid out EXACTLY what you changed.