What if Earth suddenly stopped spinning?

Get a copy of What If? 2 and Randall’s other books at: xkcd.com/books
More serious answers to absurd questions at: what-if.xkcd.com/
What would happen if the Earth and all terrestrial objects suddenly stopped spinning, but the atmosphere retained its velocity?
Randall Munroe is the author of the New York Times bestsellers What If? 2, How To, What If?, and Thing Explainer; the science question-and-answer blog What If?; and the popular web comic xkcd (xkcd.com). A former NASA roboticist, he left the agency in 2006 to draw comics on the internet full time.
Henry Reich is the creator of MinutePhysics and executive producer of MinuteEarth and MinuteFood and founder of Neptune Studios (the parent company for all three youtube channels).
Credits
Narrated by and based on "What If?" by Randall Munroe
Written & Directed by Henry Reich
Illustration and Video Editing by Lizah van der Aart
Illustration and Animation by Ever Salazar
Music & Sound Effects by Know Art Studios
What If? The Video Series is the official adaptation of the What If? books by Randall Munroe and is produced by Neptune Studios LLC.
©2023 xkcd, inc.

[@kasterborous1701]

“First, nearly everyone would die; second, things would get interesting” should be this channel’s motto.

[@Hexagonaldonut]

Sometimes the "nearly" will be absent, sometimes it's just everyone in the immediate vicinity, but no matter what, you can be sure that *something* interesting is happening.

[@daminam]

It already is an inofficial motto

[@theswordofthespiritspeakstoyou]

not true... we live, everyday... without rotation... because there is no such thing as earth's rotation, it's a lie

[@Electricth9]

as a person who has read all of his books especially the What If? books I can confirm that this is true

[@chersegems2315]

Right up there with Kurzgesagt's "Short answer: you'd die."

[@DavidTriphon]

"They'd probably be confused, until someone noticed that the Sun had stopped moving across the sky. Then they'd be really confused." This sounds like a perfect setup for a horror story.

[@idontwantahandlethough]

I'd watch the crap out of that!

[@0topon]

Sounds like a film that is directed by Roland Emmerich

[@Saukko31]

Was there Outer Limits or Twilight Zone episode where the Moon suddenly grew much brighter and people realized that the Sun must have grew much brighter, torching the daylight side, so people tried to escape towards west to at least delay the inevitable sunrise.

[@MrTVx99]

The sun rotates extremely slowly at the poles. It'd take them a few months to even realise

[@synchronos1]

[Edit: I was wrong.] I'm not sure they would notice it at all. On the poles the Sun doesn't move anyway on the sky during the day, it only moves due to the Earth orbiting the Sun. On the pole it should keep moving just normally, with the speed of 6 months from sunrise to sunset.

[@JosephStalin1941]

My grandfather, a US Marine, was stationed in San Juan, Puerto Rico in August of 1955 when Hurricane Connie struck the island with wind speeds of 140 miles per hour. He had been ordered to take shelter in a concrete bunker with six feet thick walls only a few meters uphill from a large sandy beach. After spending days stuck in the bunker, he said that after the storm had subsided and they were able to go outside, the sand from the beach and the wind had acted like a sandblaster and reduced the thickness of the wall to only 3 or 4 feet.

[@jeffreykirkley6475]

Noted. Not going anywhere near a beach during a tropical storm

[@jokerchrist2545]

Your grandfather was a member of the US armed forces and your online persona is of our enemies' greatest modern time leader. Embarrassing.

[@JosephStalin1941]

@@jokerchrist2545 your profile picture is anime. I am well aware of both world and United States history and the atrocities committed by the Soviet regime. I have made this my channel name to mock Joseph Stalin and promote anonymity.

[@shottyjonny3972]

@@JosephStalin1941based (mocking political leaders of all kinds is funny)

[@Alernategem]

@@JosephStalin1941weakest Stalin poster vs strongest joker poster

[@lemeres2478]

3:55 Great job breaking everything, ANDREW.

[@jeremykothe2847]

Dammit Andrew...

[@Boss_Tanaka]

Better Andrew than Putin

[@Ifrah-qd9to]

GOD DAMMIT ANDREW NOT AGAIN! THIS IS THE THIRD TIME THIS WEEK!

[@monst3r_child832]

Nice Job Breaking it, Hero

[@nthgth]

​@@monst3r_child832 "TV Tropes will ruin your life"

[@residentgeardo]

"This is all Andrews fault" 🤣 These videos are brilliant... very enjoyable to watch!

[@krissp8712]

I feel like Andrew got thrown under the bus there!

[@StevenBara]

Let's all hail to our overlord Andrew, so he may not stop the earth from rotating... until we all move underground.

[@cesare_1302]

The Andrew's Apocalypse

[@cesare_1302]

@@RepentandbelieveinJesusChrist5 a bit off topic my friend

[@ChrisM541]

This was a poor qualityvideo. To say that the Earth instantly stopped while the air kept its same rotation is nothing more than clickbait. The much, MUCH more interesting video - and one that most folk thought this would have been about - is "What would happen if the Earth SLOWED down to a stop?".

[@xetto]

i always thought that if the earth stopped spinning we would all get thrown off the planet 💀

[@zymosan99]

well Andrew specified that everything on the earth would also stop

[@Simpson17866]

That's the typical scenario, but Andrew specifically asked "What If we did it differently in this version, how would that change other things?"

[@fighteer1]

If supersonic aircraft don’t fly off the planet, you wouldn’t either. The velocity needed to get into orbit is about 27 times the rotational velocity of the Earth at its equator.

[@Pfhorrest]

Part of the question assumes that everything on the surface also gets magically stopped. If not for that, then things on the surface *would* be launched at supersonic speeds, although that's probably not enough for escape velocity still.

[@ThatOpalGuy]

your momentum would remain and you would continue to travel even if the earth stops spinning.

[@hiftu]

Solution: We never ever again let Andrew near to any computers to ask for such disaster.

[@thefrub]

Randall is a multi-talented guy, I've been a fan of the comic for years and never knew that he could narrate videos too. You should have done this years ago!

[@krissp8712]

I'm sure there was something stopping him, but yeah I wish there was more of this earlier!

[@danwhite77]

He sometimes tours when a new book comes out. If you get a chance, do yourself a favor and go see him. He could be a standup comic, he's hilarious in person.

[@noneofyourbusiness4133]

You removed the cutest bit of this, where the moon says “hey… hey earth? What are you doing? Oh no… oh no. Don’t worry. I’m there for you” that part made me CRY and you **cut it.**

[@neminem233]

Was this on a patreon or something

[@jackgreenearth452]

@@neminem233 No, it was in the original book, What If?, lol

[@neminem233]

@@jackgreenearth452my bad oopsies

[@absolutetrash7880]

can't give too many spoilers

[@cassandradawn780]

@@DrKaii find whimsy and joy in your life

[@nemtudom5074]

2:05 The implication that they'd notice because the cats not moving is just hilarious!

[@MrToberton]

🤔 What if a Dinosaur 🦕 wiped out the Asteroids

[@lambentlamprey]

We would worship it as a god!

[@moocowpong1]

I like the thought of the moon acting as a battery for storing angular momentum, just in case we ever stop spinning for some reason

[@prdoyle]

Didn't mention the oceans rushing toward the poles due to lack of centrifugal force, or the immense earthquakes resulting from the equator suddenly finding itself 21km "higher" than the poles.

[@Buffalo_Soldier]

Great points. There could be part 2 to this. Also he could answer how much would moon fall "down" and how long would it take until it gets tidally locked...

[@theswordofthespiritspeakstoyou]

stop spreading bs! Centrifugal forces would have the oceans lift from the earth if they existed.. but earth does NOT ROTATE!!

[@DeputyNordburg]

Well this is sort of magic. The Earth stopped rotating (for some unknown reason) but the air did not, even though it's part of Earth. I mean you can sort of make up anything. And the Cats rose up to take political power and force the dogs into slavery...

[@alyero6341]

@@DeputyNordburg only the air did not stop in the scenario

[@mtarek2005]

@@sipo-ex2qp there is likely a small effect but it's likely to only be a few meters

[@classifiedveteran9879]

You've forgotten the absence of the centripetal effects on the Earth. *The entire planet's tectonic surface would be destroyed.* I've noticed that a lot of people overlook the equatorial bulge collapsing whenever answering this question. The earth is 27 miles _(43 kilometers)_ wider in radius due to its rotation. If it stopped spinning the tectonic plates and magma would fall. I haven't done the math, but I strongly suspect that the equator would generate massive circular waves heading for each of the poles. The waves would _"condense"_ and get bigger as they headed toward the poles, hense getting bigger. This would result in the tectonic plates shattering and exploding along the way. If I recall correctly the tectonic plates are only 50 miles k_80 kilometers)_ thick in certain areas. These waves would collide with themselves at the polls creating massive explosions launching debris into space. The Earth's surface would likely be remolten into magma Earth.

[@niceguy191]

Ooo, yes this part of it is really interesting to explore!

[@classifiedveteran9879]

@@niceguy191 Yes, once again this is my intuition, saying what would happen. The only thing I do know is a 27-mile-high mountain collapsing around the equator would kill everyone on Earth in a relatively short period of time, and no bunker would be safe. The final survivors would be anyone in orbit.

[@qwertykeyboard5901]

I'm not convinced with the remelt thing, but that would still be extremely unpleasant.

[@classifiedveteran9879]

​@@qwertykeyboard5901 Fair point. And definitely not pleasant at all. 😅 This is again, as stated earlier, only my intuition. I'd be curious how close to the truth my intuitive grasp on planetary physics would be.

[@bbgun061]

@@classifiedveteran9879 Would it really collapse, or just subside? Rocks don't move or bend very quickly. The ocean bulge would collapse faster, meaning the equator would see a rapid drop in sea level while the poles would be flooded...

[@AM-we1es]

Nomad civilisations following the never-ending twilight/dawn over the course of a year in that small habitable zone between the scorching day and freezing night sounds like a banger post-apocalypse

[@juliavixen176]

I think there's a story about robots doing this on the Moon. (The Moon's surface has sunlight for two weeks at a time.)

[@stylesrj]

And they'd probably have to endure the harsh winds as hot and cold air are in constant collision between the two extremes...

[@danielmcdonald809]

Kim Stanley Robinson's 2312 has a non apocalyptic version of this scenario set on Mercury. The human habitat follows the terminator on tracks. As noted in response to a similar comment, the Mercurians have the advantages of a slower terminator and no oceans. Like all of his output, worth reading

[@rhapsodyaria]

The answer to this question in the original What If? was a formative moment for me as a young teen. I got the book from my uncle and at that point was pretty deep into this very... cult-level Christianity belief that humanity was the most important thing and the whole world was _for_ humans. And the end of this answer, the idea that the Moon's orbit around Earth would slowly cause Earth to rotate again, it opened my mind in a very significant way to the idea that the universe will keep going after humanity is gone. The world will keep turning, quite literally. That there is reality before and after humanity. It's a difficult feeling to describe. It's not existential dread, I've never feared human extinction exactly. But it's certainly an existential sort of feeling, even now as an adult who's left a lot of those old beliefs behind.

[@Boardwoards]

the people who do live in fear of such are the ones who try to use good messages to say greedy things. self correction seems to be a law of physics.

[@rhapsodyaria]

@@Boardwoards There are certainly many systems which seem to naturally stabilize. Though I'm not nearly knowledgeable enough of physics to understand the extent of it.

[@jaelwyn]

​@rhapsodyaria In some fundamental sense, it is "built in" to the laws of physics. If you wave a wand and magically suspend them somehow (pretty much the basis of every What If), but them allow them to resume, the will seek out an equilibrium state once more. Which is more or less what they were doing before we came along and messed with the universe, so it isn't really all _that_ surprising that it looks similar... but that doesn't make it any less profound, either.

[@ubiquitouscelery]

Your reaction reminds me of when I first visited the Grand Canyon, or the ocean. You can see an object so big, so familiar yet foreign, that it makes you feel small. Not insignificant, per se, just ... life changingly eye opening. Almost like you gained a point of reference for reality itself. You use existential, I use awe. Awe is just the bottom falling out of your perception xP I'm so encouraged to hear that something like XKCD made such a difference for you, because I'd be lying if I said it didn't shape me at least a little too

[@dotwarner17]

You must have missed all of the versus of the Bible that point out how insignificant humanity is in the face of not just God but the entire universe in Sunday School.

[@BigBaddaBoom]

As a teen, I wanted to write a post apocalyptic book about this. I wanted parts of it to be written in odd styling, like reading from an old book. And I carried the starting line with me for years. In the seventh year of the war, when the sky fell upon the Earth with unimaginable terror, all things built above the land were torn asunder, and all things dug below the ground were left for plunder.

[@oncedidactic]

Love it. When does the book come out? ;)

[@theporgwholived9606]

@@oncedidactic Here just for the reminder

[@boop]

Do it

[@seraphinw1]

Too bad the title "The Day the Earth Stood Still" is already taken

[@Scanlaid]

Like a combo of Remina and Canticle for Leibowitz? Sounds cool!

[@Pfhorrest]

Would the moon's deceleration as it spins up the Earth again not be enough to drop the moon out of orbit entirely? Since the moon began as a blob of molten spinning Earth flung out into orbit.

[@spychopath]

Possibly. It would for sure drop the Terra-Luna distance. Whether it would come all the way down to the Roche limit is indeed an interesting question.

[@xCorvus7x]

Depends on how much energy went into the Moon's creation.

[@Titanic-wo6bq]

I'm no scientist by any means, but if I had to guess the Moon probably wouldn't get down there all the way; currently the Earth spins way faster than once every ~28 days, but if the Earth suddenly stopped spinning it probably wouldn't take much tidal forces to get our planet to tidally lock to it's unusual moon. This is just a guess though as I am no scientist.

[@frantisekvrana3902]

My guess is that it would crash and burn, while also imparting the last of it's angular momentum to Earth.

[@doxielain2231]

There's a kurzgesagt video on what would happen

[@lenathefirst_4574]

I remember reading this when I was younger in What If 1 and having a massive existential crisis. Good times thanks to Andrew

[@arnevethamuda7959]

Yep, i also recognised it from the book, red it today

[@Gorvinhagen]

The narration for these videos is top tier. Eloquent, relaxed, and natural. No insanely compressed and bass-boosted voice, which (at least to me) seems insanely common these days. It's the little things, man.

[@AlexTiktinsky]

"Well first, nearly everyone would die. Then things would get interesting" - Literally every single What If? or Kurzgesagt video

[@alexsdarkclubband]

Death and destruction are just minor inconveniences. We're here for the physics!

[@lake5044]

In 2:52, wouldn't East facing shores experience the opposite and have hugely receeding water exposing more land under the ocean?

[@thomasprice7893]

Yeah but what does that practically matter to them - they're not going to do anything useful with that land before the water recedes into its original position He mentioned the West because they're the dudes who would get wiped out

[@Sussychu]

I believe you’re right

[@bbgun061]

yes

[@RustyDust101]

For quite some time, yes. Until the oceans' waters come rushing back, generating a reverse tsunami. But don't worry, humanity wouldn't experience that, as the tectonic plates along their edges would break off and pulverize, send enormous amounts of magma streaming into the sky to fall back down and burn everything on this planet into cinders.

[@alenazwiep2996]

For a couple days, maybe, until the water settled back to whatever the new "normal" was. But that's more of a "huh, interesting" and not the "*EVERYTHING YOU KNOW AND LOVE HAS BEEN RIPPED AWAY*" that the west shores would get.

[@QuantumPickleJar]

Your comics filled my childhood with a budding interest in STEM concepts, now I find myself all over your What If books!

[@KrishnaPrasad-nq5xp]

Andrew woke up and chose violence 😂

[@IanZainea1990]

Once had this discussion during a smoke break, we imagined us just slingshotting into space at 1000 mph, as our flesh ripped off our bones

[@anophelesnow3957]

Difficult to light the cigarettes, too.

[@eetuthereindeer6671]

You shouldn't smoke, at least not in public

[@bazpearce9993]

@@eetuthereindeer6671 Yes Mother.

[@irrelevant_noob]

Space?! That'd be an unexpected result, considering the escape velocity is 11.186 km/s, about 20 rimes (±) as much as what the "emergency break" would cause. 🧐

[@Blackadder75]

@@eetuthereindeer6671 who says he was in a public space? most smokers are banned into hideous smoking areas these days, he could just have been there with a fellow addict

[@GamerOfFate]

A Ron White quote was not among the things I expected from this channel, I love it.

[@55seddel]

He caught the “Tater”

[@menorak]

I have never until today realized that KZbin and Randall is a perfect match. Much like our ever faithful companion Moon, making sure we don't stop rotating for long.

[@gxalcremieshiny4229]

Moon's a homie for clearing up Andrew's mess

[@JWhitePWC]

ah, the classic first question of the book! i've really been enjoying these videos, keep up the good work!

[@THATGuy5654]

I was about to be smug at the fact that I live in Wisconsin, which appears to be outside of the worst of it, but then I remembered that I also live within spitting distance of Lake Michigan. Even if Michigan gets hit with the hardest waves, the thing about water is that it sloshes back.

[@AndyZach]

That would happen with the oceans too. Don't be too comfortable on the east coasts of the continents during this event. Your time is coming, maybe 12-24 hours later.

[@jasonpatterson8091]

Winds just under supersonic speeds aren't going to treat you much differently than winds just over supersonic. 41° isn't too far south of any part of Wisconsin on a global scale.

[@Kombivar]

I can't wait for the mole of moles episode :D Awesome stuff Randall! I Love "What if?"

[@ethaisa1239]

got ur book for christmas and i loved it, hope keep making cool things man!

[@AIRDRAC]

I assume people who were in a plane would also survive the immediate stopping of the earth, as they are moving relative to the air around them, rather than the ground below? Of course that wouldn't be much of a help, when they eventually need to land, or get caught up in one of the massive thunderstorms.

[@superchinmayplays]

they would suddenly be moving at supersonic speeds relative to the ground

[@xseros7954]

but not relative to the air around them, so assuming they can somehow land in all the carnage on the ground, they do have a good chance of survival @@superchinmayplays

[@oliviapg]

It depends whether they're counted in "all terrestrial objects."

[@linutux]

so, how long would it take for surface to air friction to slow the airspeed near the ground to safe landing(and parking) speed? assuming that there is a runway left to land on.

[@heffmarktwo]

I’d think they’d only have a chance if they were flying west to east (the same direction as Earth’s rotation), if they were traveling any other direction they would suddenly be moving at supersonic speeds relative to the air around them and their aircraft would get obliterated by a 1,000 mph crosswind

[@sagacious03]

Love this series! Super excited for more like this! Thanks so much for uploading! Might comment more later! Also, doesn't centripetal force which widens it's radius mean Earth's surface gets torn apart, as I've seen in the comments?

[@trooperdgb9722]

Love your work. Have just finished re-reading your 2nd What if book...and now I find your chanel! Having a good day... lol

[@sTraYa249]

What a great channel, a great find. Thanks

[@nutsbutdum]

This sounds like the beginning f post-apocalyptic movie. Imagine taking the subway for work in the morning and the moment it takes you to travel to the next station and emerge, everything at the surface has been blown away.

[@0topon]

and on the horizon you see a tsunami coming

[@JRufu]

@@0topon if you're on the West coast.. Boston, New York or Toronto, less so..

[@chadportenga7858]

@@JRufu East Coasts of continents would probably experience extremely low tides, possibly even dry bays (like Tampa Bay during Hurricane Ian in 2022)

[@chemistcraft3007]

That first line was always my favorite first line of any question, purely because of how memorable it is lol

[@sirbill_greebi3811]

"First, some boring stuff. Mass extinction. Super-sonic winds. The surface of all bodies of water completely atomizing. Yada yada... Then the moon does something cool."

[@Sl4te]

One of my favourite parts of your book. Many thanks for that.

[@beanorama]

I love you guys i bought your books a long while ago and i overall just love you Randall

[@MisterMarin]

Anakin would convince Earth to start spinning again by saying "try spinning, that's a good trick".

[@AliceKMay]

I think I remember reading a similar topic from one of your books. It's very nice to hear your explanation here. Great work. Appreciate it.

[@Titanic-wo6bq]

This was the first question in the first What If? book

[@AliceKMay]

@@Titanic-wo6bq Thanks. It's been some time for me. Time to re-read that book!!

[@yarsheets4572]

I think it's great that you're putting What If on KZbin, Randall. What a marvelous idea.

[@kittyborf]

so thrilled you're doing this content. it's been a blessing while doing late-night baby shifts. hope you're well. (hi randall).

[@Phootaba]

You're much nicer than me! When I got the question for a friend, I only stopped the crust and innards. This letting all people and non crust items, and the ocean continue spinning

[@GBHighlands]

Everything and everyone below polar latitudes getting shoved west at supersonic speeds would make for a very short video

[@lilyherman1235]

Loving this channel! We need more ridiculous science videos like this. It's like short form, video version of the book "The Martian".

[@HoppingSkipper]

Fun fact: Wil Wheaton, the person who narrated The Martian’s audio book, also narrated the What If? books!

[@TheBondsJamesBonds]

⁠​⁠@@HoppingSkipper Wil Wheaton, the person who reads the less cool version of the Martian. Signed, the RC Bray gang.

[@MrHack4never]

Look up "XKCD What If?"on Google, It's the comic strip version that lead to the creation of this channel, with a lot more answers already out

[@HoppingSkipper]

@@TheBondsJamesBonds I never understood why people get so caught up over the change in narrators. I’ve heard both, and liked both.

[@TheBondsJamesBonds]

@@HoppingSkipper I mean, yeah. It’s a good book. I did describe it as “cooler” which I thought would be a dead giveaway away that it’s not very serious.

[@4RILDIGITAL]

What an intriguing video. Got me thinking about the terrifying yet fascinating consequences of such a dramatic event. Thanks for presenting these complex scientific concepts in such a digestible manner.

[@arcticike8017]

I love how this video ends with a possible looming threat of a majora's mask style angry moon plummeting out of orbit due to its slowed orbital velocity. Thanks Andrew. lol

[@danielhale1]

The two What If books are among my favorites in my collection, and I sometimes pull them out to reread them cover to cover again. It's pure joy learning about a near-lightspeed baseball or a lake that has nightly lightning storms. I'm delighted by the rise of this channel!

[@iantbailey]

In the 2nd grade my teacher asked us how many days the earth would have if it did not rotate. The animation in this video is exactly what played in my head. I answered, exactly one day. Teacher told me I was wrong and refused to let me make a case-insisted that I was simply wrong. So I guess there’s still a tiny twinge of anger over that moment of classroom injustice, but now I know xkcd is on my side. 😅

[@juliavixen176]

Yeah, the "mean tropical" solar year and the sidereal year differ by exactly one day. The one extra day comes from the Earth making one complete orbit around the sun. All the other days come from the Earth itself rotating around its own axis (between the poles).

[@alexandrelima2766]

Wait but what did the teacher expect as a response?

[@iantbailey]

@@alexandrelima2766 Zero days. None.

[@MrCuttysark1982]

I love that this is now a KZbin series! 🙂

[@philipmurphy2]

Glad to see What If back, This channel knows what people want to watch

[@frantisekvrana3902]

0:34 I am so glad I'd suffer merely sub-sonic wind.

[@ralseithelonely]

Thanks Andrew. ❤

[@nathancellos]

Awesome video! Love this channel.😃

[@AlmostNamedOne]

I Fricking love this series please keep it up forever

[@horrgakx]

0:45 if the atmosphere maintained angular velocity then aircraft in flight would be relatively unharmed - the graphic here shows helicopters getting blown away, but the air they're flying in doesn't change.

[@ChrisM541]

It would make landing or changing direction interesting though ;) However, this was a poor quality clickbait video. To say that the Earth stopped while the air kept its same rotation is nothing more than clickbait. The much, MUCH more interesting video - and one that most folk thought this would have been about - is "What would happen if the Earth SLOWED down to a stop?".

[@farmcrafter1og]

That hidden cat really knows how life works😂 Great job man!

[@theatheobhv]

I really appreciate your new speaker. Thanks a lot. And now I realised is Randall himself. Great.

[@alexrogers777]

These videos have been the best thing to grace youtube in years

[@marcelohidalgo7420]

3:00 I'm from Chile, my entire country is under the ocean at this point 😱

[@robbenada2874]

A minor detail: a spinning earth is wider at the equator compared to the north/south distance, In time, the stopped earth would return to being a sphere, which might have some side-effects also. In the shorter term: the oceans would flow downhill from the equator to the lowlands at the polls, as would of the air. Excellent episode.

[@BrianOxleyTexan]

Incredibly good video and audio content and presentation. More, please.

[@macronencer]

My memory is unequal to the task of mentally verifying whether this is word-for-word from the book, but whatever... this is a PERFECT script. Excellent!

[@zuthalsoraniz6764]

The cool thing is that some climate simulations suggest the climate wouldn't actually be that extremely different between day and night - because you would have a lot of atmospheric circulation distributing the heat around the planet. Also, the climate would probably cool down, because there would likely be almost constant overcast conditions over at least sunlit oceans on such a slow spinning Earth, which means a lot more sunlight gets reflected back into space. This also means that if we somehow cooled Venus down to an earthlike temperature and gave it an earthlike atmosphere and oceans, it would probably be able to maintain those conditions despite receiving a lot more sunlight.

[@ubiquitouscelery]

Finally, a solution to global warming I can get behind.

[@Ballrock30]

A youtuber stated he has a problem with teleportation concepts in movies because of this. If you would teleport yourself to somewhere on earth that has a different distance to the closest pole, the relative change of your velocity after you reached your destination is so high that it would rip you in pieces. Never thought about it like this and thought it belongs here :)

[@jasonpatterson8091]

So magic technology can destroy a person in place A and completely reassemble them in place B, but changing their momentum by a tiny amount (relative to the mass-energy contained in a person, I mean) is difficult?

[@stylesrj]

@@jasonpatterson8091 Isn't it these days the magical teleporters use wormholes because of that whole disassembly thing had those sorts of implications about whether or not the person is a clone or the actual person?

[@catprog]

So You've Learned To Teleport by Tom Scott. It is about the same energy as a sip of Cola.

[@ThatKrazyLunatic]

love this channel, love the books

[@annetteziegler7944]

Thanks a lot, Andrew.

[@Lurulf_]

Wouldn't everyone just fly into the walls if the earth suddenly stopped moving regardless if they are over or underground?

[@PhalanxRises]

It would, but Andrew specifically said that everything on the surface would magically stop too, only the atmosphere would keep moving. So the assumption is we also magically stop without feeling inertial effects.

[@magnushultgrenhtc]

I think so. Indoors, you can probably only survive the jolt if you're very close to a wall in the right direction. Maybe not even then. Your inertia would be 1,000 mph relative to the surroundings. That would the reason for the caveat about *everything on the surface except the atmosphere*. Gotta be careful with the wording in thought experiments...! 😄

[@MonkeyJedi99]

@@PhalanxRises That tricky Andrew, saving our lives long enough that we get to regret our survival!

[@albinobluesheep]

@@PhalanxRises All the airplanes not on the surface would keep flying and be very confused where the ground below them went Any one unlucky enough to have jumped off the surface would seem to be thrown sideways likely into the closest wall

[@Boardwoards]

@@MonkeyJedi99 truly!!

[@BentleyCreates]

0:25 *supersonic* speed

[@bluey-next777]

1:09 FIRE IN THE *Bunker*

[@thenixer209]

This reminds me a lot of an HG Wells short story included at the end of some editions of _The Time Machine,_ about a man who gains the ability to warp reality with simple wishes. One of these miracles ended up essentially being "stop the Earth spinning," which caused a catastrophic rush of wind that tore up everything on the planet and basically levelled its surface and killed almost everyone; save for the man who very quickly saved himself using his powers. Essentially _everyone had died_ apart from him in an instant, and he couldn't revoke what he'd done with another miracle until he sacrificed his powers and basically turned back time so he never got them in the first place. It was a fun story, and I remember that apocalyptic sequence for being surprisingly horrifying and grounded despite the story being quite old. EDIT: It was called "The Man Who Could Work Miracles," and this is part of the Wikipedia article on the story (spoilers, obviously!): _Maydig plans to reform the whole world. He suggests that they could disregard their obligations for the next day if Fotheringay could stop the night altogether. Fotheringay agrees and stops the motion of the Earth. His clumsy wording of the wish causes all objects on Earth to be hurled from the surface with great force. Pandemonium ensues, but Fotheringay miraculously ensures his own safety back on the ground. In fact (though he is not aware of the enormity of what he had done) the whole of humanity except for himself had perished in a single instant._ _Fotheringay is unable to return the Earth to its prior state. He repents, and wishes that the power be taken from him and the world restored to a time before he had the power. Fotheringay immediately finds himself back in the public house, discussing miracles with his friends as before, without any recollection of previous events._

[@playwars3037]

This really feels like a kurzgesagt video and it's AWESOME. We really need more stuff like this on youtube ^^ .

[@CaseyMcBeath1]

That’s great but it only is really affecting wind speed as a factor. I think everything’s inertia would destroy everything significantly more dramatically

[@eliasheid947]

True, and it would be interesting to model what would happen (Everything dies but quicker probably), but the question specified that terrestrial objects would also stop rotating

[@prdoyle]

The inertia of all terrestrial objects disappears. That's specified in the question.

[@CaseyMcBeath1]

@@prdoyle was that a line? I must’ve missed it

[@Sivanot]

If the pull of the moon on the earth would gradually slow down the moon as well, wouldnt the moon eventually fall back into earth?

[@TheCatLady65]

Yes, yes it would.

[@TARDISES]

Probably not. We might end up hitting an equilibrium point where the Earth and Moon are tidally locked, though. Keep in mind that currently the Moon is moving *away* from Earth over time, so slowing it down would probably just stop that gradual drift.

[@mickytananu5908]

This is much more detailed than the book. I'm really glad that my favorite books creator make a youtube channel.

[@thomasneal9291]

because so many comments seem to be missing the mark, let's reiterate the actual conditions specified by xkcd: ONLY the atmosphere is allowed to continue its original motion in this scenario. Everything bound to the surface of the earth no longer is allowed to move. that means centripetal acceleration of earth itself also stops. so no, no earth shattering due to the fact the earth is wider at the equator than at the poles. this is just about what would happen if you separate the atmosphere from the surface, and stop the surface, period.

[@TheComputerCrasher42]

I wonder what would happen on the west side of mountains. If all of the air suddenly rushes east, wouldn't there be a vacuum there for a short time? Kinda reminds me of the "glass half empty" What If scenario.

[@Buffalo_Soldier]

Mountain tops could get ripped apart if thousends of tonns of air suddenly started smashing it with super sonic speed. Tips would fall off and I wonder how much meters of tops would that be (probably not many... rocks are quite hard and tips with conic shape are pretty strong). Still, tops of mountains would face some absolutely insane pressures and velocities of air.

[@bbgun061]

Maybe not vacuum, but definitely lower pressure and turbulence.

[@ChrisM541]

This was a poor quality clickbait video. To say that the Earth stopped while the air kept its same rotation is nothing more than clickbait. The much, MUCH more interesting video - and one that most folk thought this would have been about - is "What would happen if the Earth SLOWED down to a stop?".

[@zuke1624]

Wouldn't 1000mph wind also impart a massive amount of heat on the Earths surface? I know you mentioned that on the oceans, but I mean EVERYWHERE.

[@hurktang]

Yes but somewhat slowly. The energy of the wind would be mostly kinetic on contact. If you are in contact with it, the temperature is not your main concern. I think Randall's point is that it would be warm/pressured enough to cause massive rain storm over the planet.

[@juliavixen176]

I think most of the heat would be from pressure, not friction. Any supersonic object will compress the air just like a piston in a cylinder.

[@ChrisM541]

This was a shockingly poor quality clickbait video. To say that the Earth stopped while the air kept its same rotation is nothing more than clickbait. The much, MUCH more interesting video - and one that most folk thought this would have been about - is "What would happen if the Earth SLOWED down to a stop?".

[@stepanvejvoda2725]

I got your What If book as christmas present and it is great and so fun to read!

[@bringingbackbrawl]

WAIT, IS THIS ACTUALLY THE GUY THAT WROTE THE WHAT IF BOOK? I absolutely adored that book, genuinely my favorite literature of all time. Glad to see you're still doing this awesome stuff, man.

[@BurrritoYT]

the nostalgia

[@Gameboy-Unboxings]

0:57 thats some logic. Like as if that bunker is just going to 100% hit your bunker...

[@vitamins-and-iron]

it’s an example lol

[@Gameboy-Unboxings]

​@@vitamins-and-ironok? An example can be a shitty example.

[@kitsune2858]

Andrew's question should have been, what event would cause the Earth to stop spinning? And that's where it gets fun! at 2:52 you should have said the end of world history lol! And on a side note, we can expect earthquakes because the tectonic plates will be shifting hard, not to mention all the volcanic activity. But the worst will happen when the atmosphere AND magnetosphere are reduced to practically zero. This is our shield from radiation and space, and with it gone, the cold of space will reach the surface of our tiny rock and flash freeze everything it touches. I hope Andrew is happy now :)

[@Mikeztarp]

Nice job, Andrew!

[@connycontainer9459]

Just finish your homework Andrew, it's not worth it.

[@BR-lx7py]

Didn't you miss the part where all humans would turn into a mush because their 463 m/s velocity (at the Equator) would become 0 suddenly? That's 46g-s if the deceleration takes 1 second.

[@bbgun061]

I think humans are considered to be 'terrestrial objects' for the purpose of this question.

[@terdragontra8900]

Arguably, humans that magically have their velocities of every atom in their body changed instantly wouldn't feel anything, unlike with normal acceleration, which propagates throughout the body in a wave causing damage.

[@BR-lx7py]

@@bbgun061 Right, so humans suddenly stop spinning and experience 46g acceleration.

[@bbgun061]

@@BR-lx7py it's assuming some magical force that stops earth's rotation without any g forces at all. it's a silly "what-if" question and isn't meant to be taken so seriously!

[@videoket]

I keep feeling the impulse to search for mouse over text, like I’d find in the comic. 😂 I like that we still get some of those funny asides via captions and such; that’s one of my favorite things about xkcd!

[@dracofirex]

I saw a very good video about this same topic only the Earth slowed down its spin over time to a crawl, then stopped. It showed how people's circadian rhythm was affected, how the water and even breathable air started heading to the poles due to the spin not keeping the air focused on the equator, and all sorts of things. This scenario where the atmosphere kept going and the Earth suddenly halted was great!

[@albevanhanoy]

DAMMIT ANDREW

[@bami2]

1:46 I didn't know everything below ground doesn't have an atmosphere and is essentially a vacuum.

[@M4niacks2]

I guess they would still have terrible things happen, but the event would be contained in a matter of seconds, survival would not be guaranteed, but more likely than above ground. Anyone standing would be flung toward the nearest objects by the verys hort lived burst of wind and probably die, even if happened to be sitting in a corect axis, with the wind blowing directly in front of you, pushing you stright in your chair, you could still die if your head isn't rested against something, then from having anything thrown at you. Probably won't be comfortable even in those perfect conditions, but If you didn't die or suffer serious injury after the initial "impact", you'll survive, the sudden and extreme change in air pressure might leave you with ear damage tho.

[@barryf7253]

Carl Sagan once calculated that the energy needed to stop the earth spinning would melt the crust. So everything would basically die.

[@Dewaxel]

The sound effects are really fabulous.

[@xCorvus7x]

Would the Moon slow down enough to leave its orbit?

[@idontwantahandlethough]

and which direction does it "leave it's orbit" in? The way where our little friend slowly drifts off into space, or the way where it murder-sui's us? I haven't done the math, but I have to imagine it's the latter.. right?

[@OrcinusDrake]

Currently, the moon is slowly receding away from us. If the earth stopped spinning, then the moon would slowly close in on us. But I'm not sure if the moon would collide with us, would get tidally locked, or the sun expands and makes the question pointless.

[@xCorvus7x]

@@idontwantahandlethough Yes, that'd be it.

[@DAPower98]

Oh shit, I didn't know you have a channel. SUBSCRIBED!

[@shadepizza4217]

I love the detail of Andrew having the black hat

[@EBFilmsMan]

There's a wonderful speculative documentary made a few years ago that touches on this same subject. I still rewatch it occasionally.

[@bodkinsbestphotography]

I love these videos.

[@JosephGallagher]

Loved the sound effects on this

[@duhby]

2:03 "I haven't had to move in a while" is golden

[@JD-ck6vg]

Thanks a lot Andrew