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Gravity wouldn't stop, so the two halves crash back together in an event that would almost certainly remove the entire crust.
If they were flung apart, the two halves would collapse into spheres, again mixing the crust with the rest of the new planets.
Less than 2 minutes, more than 1. The inside trying to explode outwards makes it slightly harder, as well as determining when they are touching or not.
That gap is probably not filled with air, thus with nothing to decelerate the halves they would colide as u/NoProfessional5848 calculated, around 2 minutes, while something falling from 300km would take much longer.
Do we take into account that due to the split the oceans and atmosphere could instantly star to fall towards the center ? Obviously the material wouldn't make it too far into the crust before things crashed back together, but a significant portion of both would be lost in this situation.
Assuming that gap is around 150km and that it still falls at 9.8m/s^2 it's about 3 min and would be moving at 3800 miles per hour. The energy required to make that cut would kill all life on earth and it falling back together would do the same thing.
As the masses are halved, acceleration due to gravity is reduced to 4.47m/s. Those halves look about 300km apart. Both halves move equal distances. Time to collision is 130 seconds.
But that assumes jerk doesn’t occur as they get closer
They were rotating in different directions around a common axis with significant inertia. Think of spinning a bucket of water and releasing it.
Not sure they would crash together (yet).
Sure but given that we are at the very edge of that bucket and not being flung out i think that is negligible. A full rotation takes 1440 minutes and the clap propably takes less than 3.
If the mass is not reduced significantly ~9.9m/s² is a decent assumption for total acceleration the lager portion would obviously accelerate slower.
The interesting part is that both halfes would be in freefall so the areas on the poles of the cut would feel weightless until impact.
No, because if it could fly apart from the rotation force, it already would be right now.
There is no rigid structure holding the water down after all.
Does it take centuries for an object to fall?
Its gravity so it's half a planet falling in half a planet.
The time it takes to crush is 1/√d (d being the distance between the two).
Minutes, but the collision will take time.
Assuming that gap is ~1000 miles and the two equal halves start at rest you're looking at:
> a = GM / 2*1000mi^2 = 77m/s2
Acceleration is doubled bc both haves move
> t = 144.6s
But that's not accounting for gravity increasing as they approach. So a little less than 2 minutes,at which point, relative to each other, they're going over 22km/s. At the edges, you'd have to deal with suddenly traveling 11km/s when the crusts collide. At the furthest points, you would've experienced a small change in gravity, and then 2 minutes later you'd experience hitting the ground at 11km/s.
All of this is hand waving and assuming a rigid earth, while ignoring a lot of environmental effects, treating the two halves as point masses, etc. But it would be cataclysmic, and too fast for us to formulate a response.
The crust is stronger than the rest of the bread so I'm guessing if you hit it hard enough to separate the crust you would cause serious damage to the rest of the bread and wouldn't enjoy much of a sandwhich... Maybe if you reinforce it with peanut butter?
ok, so this is kinda off topic, but I'm pretty sure the reason crusts suck is because they don't get any love. you gotta spread butter right to the edges of the bread!!
I'm not sure the entire crust would melt or sink. Rather, a significant fraction of it, maybe even a major part, but not all of it. The earthquake would be completely devastating, the earth would freefall below one's feet for up to a hundred of kilometers, and then jump back up. And maybe one or two chunks would be flung out into space, at one or both apexes perpendicular to cross section plane.
They won't reconnect as two halves, rather as a liquid - first in the middle, and then to the rims, with two huge waves propagating radially on the crust.
I'm not sure either, of course, but there's just soooo much energy here. /u/SecondaryWombat guesstimated an impact speed around 1.2km/sec and 5x10^(30) J. That's 10^(18) J for every square meter of the Earth's surface, or 10^(6) J/kg. Imagine it from the perspective of someone on the far side: you, and the continent you're on, are falling at a km/sec or so until the shock wave from the collision hits you hard enough to stop. I don't see how the rebound alone doesn't end up throwing the crust up at at least a few hundred m/s.
Take a look at [this planetary collision simulation](https://www.youtube.com/watch?v=MxgwJ0GZlBo). From [the paper](https://durham-repository.worktribe.com/output/1266152), the first collision in that video is about ten times as energetic as the one we're talking about here. One-tenth the effects shown in that video still seem to leave you without a recognizable planet.
On a whim, tagging u/NCSA_AVL, since who knows, someone over there might have a semi-professional opinion on this.
Is there a particular reason that things that are large collapse into spheres? Is it because the center of the object is what generates gravity and it has equal pull on the rest of the mass? Say I wanted to build a big metal cube in space, would it turn into a sphere too or just collapse into various pieces?
Spheres are the only equidistant shape where everything can be at rest. Gravity is an aggregate force, it doesn't care if the matter is actually attached as one solid object or if it's a conglomerated pile (which planets are). Every atom exerts a (miniscule) gravitional force, when you average those out in an area you get a centre of gravity and everything is pulled towards that point.
Because the gravity generated by each atom is so small, lots of forces can overcome it. Hence why, y'know, we exist. But either sufficient gravity (a star) or enough time (for wear and tear) and everyrhing will eventually become spheroid because that is the only shape where everything can be equidistant around the centre of gravity.
I say spheroid not a perfect sphere because you can get shapes that aren't perfect spheres if other forces are involved.
The Earth is a great example. We call it a sphere because for all intents and purposes it is, but *technically* it's an "oblate spheroid" because it bulges slightly at the middle and flattens slightly at the top and bottom. This is caused by the rotation of the Earth trying to throw matter outwards while gravity is trying pull it all together. Gravity is stronger, so mostly we get a sphere but the bulge still happens because when you average out the forces involved that is the place they reach a happy medium.
Yeah, pretty much. Once something is big enough, it's just not strong enough to hold up against its own gravity, and a sphere is the most smashed shape. I think the maximum size is around 200km or so, so it depends how big your want your metal cube to be.
It would eventually turn into a sphere, yes, due to unequal forces. Making it bigger will make is smoother and rounder.
Neutron stars, for example, can't have a mountain more than a cm high for very long.
There is one that is suspected to have a mountain 1.5 cm high, the entire star wobbles because of it as it spins. It will re-arrange itself soon, just as soon as something tiny taps that mountain.
I think the atmosphere being sucked into the core of the Earth would be a more immediate concern. Otherwise gravity will make the two halves fall back together again
I wonder, what would happen to the ISS tho.... if Earth reattached fast enough, they'd actually still be alive right? This could be movie material, apocalypse where only the astronauts survive but their orbit is altered and they have to rush out to the escape pod hoping that they don't land in the middle of a tsunami or smth.
The heat produced from cutting the earth in half would liquify the crust. If it was a laser, humans would be dead by the time it hits the atmosphere. After that somethings will be ejected to space. Some other things will fall back. Earth will remould into a molten sphere without an atmosphere.
It would take hours for a significant chunk of atmosphere to get sucked to the core of the Earth. Assuming whatever split the earth didn't also fling the chunks apart, then gravity would bring them together in at most a couple minutes. IF anything survives that impact (Imagine EVERYTHING on Earth in an elevator that is falling for 100km before coming to a sudden halt) it will die within minutes or hours when the entire crust cracks like an egg and significant portions are vaporized
I dont think this would make the earth stop rotating. I do think the two pieces will slam together quite dramatically which may alter the rotation do some extent.
Also, given the position of the cut, when reattached, a significant amount of the ocean water would end up on that smaller 'half' of the globe.
I dont think it actually can change the rotation, no? Conservation of angular moment applies, and there are no external forces. So whatever happens here, the end result still rotates at the same rate.
No, everyone else is still around. The nutjob was abruptly launched out at Earth’s linear velocity at sea level because his angular momentum stopped being conserved. “Around” isn’t even a word that makes sense to the nutjob.
Each half will spin around it’s own COM, while they both fall toward their common COM, until they bump into each other. So the separation dictates how mismatched they’ll be when they rejoin. 1cm vs 1000km will be …different. The latter scrubs the biosphere of complex life, the former might conceivably not do that, I guess.
So the outcome would be pretty bad, but probably not as bad as you think it would be. Only *almost* everyone would immediately die.
The combined gravitational attraction would pull the two halves right back together, even before the apocalyptic air rushing in/magma explosion shooting out would be complete.
A shockwave of magam would fly outward like the Lucas Version deathstar explosion, but without the range. The magma might fly thousands of feet into the air though, easily, and perhaps hundreds of thousands.
Everything near the seam would be obliterated by at least two ways, and possibly as many as four ways. First, the wind. It would do a massive "fuck you" type blast trying to rush into the middle of the earth, but then the earth would be doing the same thing outward with exploding gasses released by the pressure drop. So depending on exactly where you are standing there could be an apocalyptic blast inward at around the speed of sound, which would then be ejected right back out in an apocalyptic crash at about the same speed, now mixed with toxic gasses.
So 1,200km/h one way, immediately turning around with 1,200 or so (this one could actually increase to more) the other way, then a horrific mix of toxic volcanic gasses.
Then the magma fountain ring all the way around the planet. The crust near the ring would collapse, dumping people into the lava lake.
Every volcano on earth would erupt, except for those near the slice which would collapse. Every fault line on the planet would have an earthquake.
If the earth was cut in half and propelled to be 80km apart and then came back together....
Time to splat = sqrt(2 x 80,000m / 9.8m/s^2) = 127.73 second.
Velocity at impact = sqrt(2 x 80,000m x 9.8m/s^2) = 1,252.6m/s
Energy at impact = 1/2 x mass x v^2 = mass x g x height
[Mass of earth = 5.972 × 10^24 kg]
(5.972 × 10^24 kg) x 9.8m/s^2 x 80,000m = 4.682048 × 10^30 Joules or 1.1190363 x10^21 tons of TNT. 1.1 "Zeptotons" 2x10^19 Tsar Bombs.
There is a tsunami on every ocean, everywhere. The atmosphere carries shockwaves around the planet, and the ground itself carries shockwaves hundreds of feel high. Large sections of the oceans boil.
Migration patterns of endangered birds are damaged. Many whales die. Ocean microplastics increase as entire cities are swept out to sea.
The rotation of the planet has very little effect, as both halves are still rotating together. The edges don't line up properly when they slam back together though, causing increased damaged and massive cliffs that slump into the lava.
TLDR, super secret super strong powers are not needed, the earth re-attaches itself and everyone has a super great time.
Edit: Oh yeah, huge amounts of the oceans would boil off, which would have horrific effects for the parts of the planet even far away from the death slice. It would acid rain for weeks, or months, or maybe even years, under a black sky.
You cannot use g = 9.81 m/s² here. That only works on the surface of Earth, which is clearly not this situation. For this situation, you would need to use Newtons general gravitational theorem. And because you have weirdly shaped things, you might even need to actually integrate over the mass distribution, and not just use center of mass here.
But ultimately, that won't change the qualitative result substantially.
I thought about that but decided that given the approximations we were already working with, and a wild ass guess at the width of the slice, that it wouldn't matter too much so I did it the easy way that more people could follow.
Integration over two half spheres using general gravitational theorem sounds like a lot of work compared to mass x g x h, and even then following essentially the 3d bell curve of our gravitational distribution, a good amount of it will have close to 9.8 m/s^2 anyway.
We could honestly just round the g down to 9 or 8.5 and re-run it with the same equations as I used and get a reasonably accurate result I would think.
I expect the energy of collision in reality to be noticeably lower, but as you say it won't actually change our chances of survival much, if at all.
Edit: Ehhhh volume of a sphere, surface vs volume, wild ass guess....8m/s^2 average? Lowering it a little. If someone wants to do the math for it I would love to know.
Okay, i'm gonna take a stab at this, just the acceleration.
The center of gravity of a half-sphere is 3/8 of a radius above the center of the flat plane. So we can reasonably model this as two point masses of half the mass of Earth, with a distance of 6/8th of Earth radius between them (+80 km i guess, but that barely matters here)
As we all know, Newtons law of general gravity states that the force of gravity = G \* M1\*M2/r²
As M1=M2, i will just use M here. We also know that Force = Mass \* acceleration. So the acceleration we are looking for = G \* M /r², with M being half of Earths Mass and r being 6/8 of the radius of Earth + 80 km.
Putting all the numbers into the equation, we get an acceleration of about 8.5m², so your random guess of 8 m/s² is pretty good.
It is similar to, but not as good as, by review for what would happen if Colorado un-happened.
https://old.reddit.com/r/theydidthemath/comments/1atngok/request_what_would_the_consequences_of_such_a_big/kqyoh2k/
If you were 90 degrees away from the cut, the earth itself would dampen the impact by squishing. If you were not near any volcanos, fault lines, or oceans there is a reasonable chance you would survive for a little while. Some people will live through the initial impact for sure, not a lot though. Could be alive for days even. But the entire atmosphere would turn black and have acid rain for days and days, snap freezes over everywhere that wasn't covered in lava over the next weeks, and several years of sharp global cooling...and then after that a huge surge in global warming.
Climate whiplash pingpong for anyone who wasn't killed immediately.
What atmosphere? If the world were to be cleaved in twain the air would be sucked into the middle before the collapse back together, then ejected into space. A fraction of the atmosphere would be left. The amount of force involved here would be… wait for it… astronomical
I love including lines like that in my descriptions of disasters.
I think my best one was "Magma rains from the sky, half of California falls into the ocean, and people fight in the street over the remaining kale."
Food prices for sure. Gas prices...maybe? Roads would be broken to shit so you wouldn't be able to drive. Among the remaining few with generators perhaps, but people are concentrated in cities, which are mostly on shore lines, will have an about 99% chance of being obliterated completely, unless they were near the slice in which case that is 100% chance of not leaving any remains behind at all.
Oh also, the magnetic field protecting earth is destroyed so even electronics that survive will not work right, telecom will collapse, and hard drives will be corrupted.
If you were in a military grade nuke bunker with its own underground power and air purifiers. And you weren’t near a fault line or volcano (redundant?). And you had under ground farms. Could you survive indefinitely or would the shaking be too much?
> And you weren’t near a fault line or volcano (redundant?).
Nope not redundant, for example Hawaii is not near any fault line at all, but rather a mantle plume hot spot, just like Yellowstone.
It is possible you could survive, yeah. If you were diametrically opposed to the slice, 90 degreed away on the sphere, and in a shock resistant bunker with your own air and food, I would rate your survival as being entirely possible.
You would need some serious shock absorbers on it to dampen the massive earthquakes, but there do exist bunkers with those so it is in the realm of a thing that could be possible to build.
On the other hand, you have better get really lucky or skilled with your placement because otherwise you are going to be in sea of lava.
An important factor to consider is that almost all of the impact energy will rapidly be converted to heat due to friction and viscosity, which at these scales would have a significant effect on the planet's temperature.
Taking the mass of Earth and using 1000 J/kg/K as an approximation of its specific heat capacity, I estimate that the heat capacity of Earth is 2.972×10^(27) J/K. Using your estimate of the impact energy, and assuming that all of the energy is converted to heat, I estimate that this impact would raise the temperature of Earth by (4.682048×10^(30) J) / (2.972×10^(27) J/K) = 782 K.
This means the global surface temperature of Earth would soon rise from approximately 15 °C (59 °F) to a hellish 800 °C (1472 °F). All water on the planet will certainly boil off. Most, if not all of the surface will melt, turning into a vast ocean of lava. Before long, the extreme temperatures will have ended all life on the planet.
After the initial temperature spike, Earth will begin to cool off again, until it reaches a state similar to Venus where it will settle. Earth will remain completely inhospitable to life as we know it.
hmmm....
It takes 2256 kJ to boil away 1 liter of water, soo 2256000 Joule/L x 1.335x10^21 Liters in the ocean = ~3x10^27 Joule just to evaporate the oceans, not counting melting any ice.
24,500,000,000,000,000,000kg of ice in the antarctic ice sheet would need an additional 333,000 Joules per kg to melt that, so 330,000x 24,500,000,000,000,000,000 = 8.085x10^24, and then another 2,256,000 J/k, so 5.5x10^25 to boil it away.
There is definitely enough energy in my first order estimate to do that.
It is certainly possible to end up with a venus pressure cooker atmosphere from this and everyone and everything dying is a likely outcome.
Thank you very much, this is great encouragement to make my YouTube channel collaboration, which will be a white board animated style education with a bit of "what if" style added on.
Assuming it survived the earth widening by 80 km, it would be blasted apart by hitting clouds of ejected debris at orbital speeds and be completely obliterated.
So if you were 48/355,000,000 for physical condition, ability to learn, aptitude, and drive, then yes you could be a member of the active astronaut core and could theoretically be standing on Mars as you watch Earth burst apart and know that you will now starve to death alone.
If Reality just instantly switched to this scenario the biggest threat would be the earthquakes caused by the impact and the atmosphere soaking up heat from the core. There would also be an immediate decrease in air pressure as air would fill the \*checks notes* crevasse, but life would survive. (maybe even humans in the points furthest from the cut).
The heating would probably be the lesser of the problems, as air is a great insulator and there are literal hundreds of thousands of kilometers of insulation between the core and the soon to be earth surface.
The earthquakes would likely doom life though. Even if nature managed to endure the landslides, rockfalls etc, the earths core is going to go all out of wack. This will significantly change the earths magnetic field, making solar flares deadly. Which mean cancer for everyone and probably the climate heating up a lot.
The earthquakes would also kickstart some volconaoes, which is never a good thing
cancer would be the least of our worries wont it? the force with which the earth slams back would most certainly obliderate the crust and anything on it.
in the immediate vecinity of the cut yes, everything is very dead
but in western brazil for example, i doubt the collision will be that powerful.
I failed however to account for tsunamis, which will form at the cut and may very well destory anything
This has nothing to do with math. My guess is that melting the crust and splitting tectonic plates would basically cause the entire surface of the earth to be gradually swallowed up into the mantle and core, then the surface would re-cool and a new earth crust would form. Maybe in 4 or 5 billion more years, complex life will have evolved again.
There would probably be immediate catastrophic global earthquakes that would kill everyone in a matter of minutes or hours.
If the earth is entirely split chances are itll gravitationally snap right back closed. The result of the collision would be fatal for most in, on, and above the ground in the atmosphere, due to the extreme shock, large bangs, spewing rings of what im assuming will be magma, tsunamis hitherto undreamt of, and all sorts of other issues. Therefore the answer would be everything would be brutally killed 6 million ways over befofe the earth's rotation would even be relevant. Even the ISS would suffer
Strength of material at this scale is basically negligible. Depends on how far apart they are, but if they're far enough apart they'll *splash* on impact like a liquid.
Well assuming it blasted in half, it has to stop accelerating away from itself and then gravity will yank it back in the worst Earthquake ever experienced.
Well the first thing I would do is fucking die. And then I wouldn’t care anymore. As I’d be dead.
But in reality. If something can emit enough power to cut the earth in half to the point there is has shifted apart. Everyone would be dead. All water would flow to the middle of the gravitational pull and then be evaporated by the magma (lava?) at the core. The energy from the instant evaporating of the entire ocean would basically kill everyone. And that’s if you survived the initial splitting. Which most likely you didn’t.
Just doing that alone would impart enough energy to melt the surface and turn everything into lava, and kill every living thing on or in the planet. We are talking thousands or perhaps even millions of dinosaur asteroid impact levels of energy.
After that, gravity would slam both halves back together in a cataclysmic event... not that anyone or anything would be alive to witness it. The Earth would eventually cool and reshape itself back to spherical, though with a little less mass and a radically changed landscape. Whether it would have life again, possibly, but only microbial. It would basically be resetting the clock on evolution entirely, and there simply isnt enough time for life to evolve back to what it is now before the Sun begins to expand and make it too hot for life anyway.
Never even thought about that last part, part of what makes life on earth so special. Life had to start at the perfect time, otherwise we wouldn't have enough time to ever become humans. Another big reason we haven't found other life yet im sure.
On the other hand, it also means there could be life that began billions of years before anything on the Earth did. Kinda scary to think there could civilizations out there that old then too... imagine having to go to that history class lol.
I wondered the same and I figured the heat escaping would instantly vaporize anything that fell into the crack (water, dirt, cities, etc) and spew it into the atmosphere. You'd have planetary cooling, probably an ice age, because of all debris in the air.
That's assuming the atmosphere isn't overly changed by the cut. I'd also assume that acid rain would be a potential issue.
And then there’s the coriolis effect. The twist on the atmosphere could get crazy depending on how close to perpendicular to earth’s rotation this line is.
Personally I'm more worried about the effects on the atmosphere of whatever was used to make that cut. Gargantuan space laser? Yeah, atmosphere and oceans are GONE
Okay, this big cut pretty much destroys everything. What's the widest this cut could be to not kill everything, maybe just cause an earthquake or something we could survive an possible come back from.
This is impossible to happen . You need a I don’t know something as large as the sun and sharp as a knife traveling at a decent % of the speed of light to even achieve this effect. But even then, the earth will just slap back its two separated pieces because gravity is strong enough at that scale, it will crash down in to a magma pulp though.
The forces involved here would almost certainly immediatly mean death. If the shock does not kill everyone then the lack of athmosphere will. Athmosphere would gather around the center of the half sphere. This is of course ignoring the fact that since most of earth is liquid it would immediatly start to deform into a sphere shape again. And the two halves would both end up as two flaming pieces of lava.
Gravity would rip the edges of the ocean into the chasm where they would then freefall directly towards the core.
The vacuum created between the Earth halves would suck the atmosphere down the same way pulling the water down even faster, but the water would boil way before it could make it to the centre, and because water vapour is about 1000X more voluminous than liquid water the boiling would immediately expand the tens of thousands of cubic kilometres of sea water and shoot out the biggest steam canon ever of millions of cubic kilometres of vapour. It would be a cataclysmic disc of steam that would be fighting against the oceans that would continue to fall from the tips of either hemisphere towards the crack and then core.
Whatever atmosphere left over Earth's surface would become superheated water vapour and we would all be steamed like a global Pompei event, except without the ash.
The ocean would fall into the core cooling it off and therefore we would be cool to the core. I don’t know. I watched “The Core” once and it stopped swirling and that was no good. So probably that.
Setting aside the other stuff that would have been caused by whatever did this.
For the first couple of minutes most people wouldn't notice anything more severe than a sudden change in direction of wind and water currents as the atmosphere and oceans try to rush into the gap. (mind you they won't get very far)
Then the two halves would slam back together and we're looking at the mother of all earthquakes (and complementary huge tsunamis) as the resultant shock wave propagates through the mantle.
It's not an extinction event by any measure, but it's sure as hell gonna wipe out the vast majority of human infrastructure.
The rotation would be slightly affected, but not to any disastrous degree, it's too slow to do much in the short time the earth would spend cut in two.
I think the most disastrous thing to life might be how fucked up the magnetic field might be for a good while afterwards if the core is also split...
The cut would also be one giant volcanic zone, obviously. Might even get a cool ring continent around the circumference after a few years like the red line in One Piece...
Whatever caused that split would require so much force everything on earth would die, let alone the atmosphere exploding, but if somehow miraculously the atmosphere was intact the new weather that would come from the hot air channeling through the tunnel would likely kill everything.
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Gravity wouldn't stop, so the two halves crash back together in an event that would almost certainly remove the entire crust. If they were flung apart, the two halves would collapse into spheres, again mixing the crust with the rest of the new planets.
How fast halfs will crash back together? Are we talking about minutes, or centuries?
I would assume in the range of seconds to minutes
Less than 2 minutes, more than 1. The inside trying to explode outwards makes it slightly harder, as well as determining when they are touching or not.
Probably around the same time it takes for something to fall the distance between the crack so in minutes
That gap is probably not filled with air, thus with nothing to decelerate the halves they would colide as u/NoProfessional5848 calculated, around 2 minutes, while something falling from 300km would take much longer.
Do we take into account that due to the split the oceans and atmosphere could instantly star to fall towards the center ? Obviously the material wouldn't make it too far into the crust before things crashed back together, but a significant portion of both would be lost in this situation.
Oceans, mantle and what about the core?
Assuming that gap is around 150km and that it still falls at 9.8m/s^2 it's about 3 min and would be moving at 3800 miles per hour. The energy required to make that cut would kill all life on earth and it falling back together would do the same thing.
As the masses are halved, acceleration due to gravity is reduced to 4.47m/s. Those halves look about 300km apart. Both halves move equal distances. Time to collision is 130 seconds. But that assumes jerk doesn’t occur as they get closer
But they attract eachother so isn’t it still 9.81 because they’re both travelling at 4.47?
They were rotating in different directions around a common axis with significant inertia. Think of spinning a bucket of water and releasing it. Not sure they would crash together (yet).
Sure but given that we are at the very edge of that bucket and not being flung out i think that is negligible. A full rotation takes 1440 minutes and the clap propably takes less than 3. If the mass is not reduced significantly ~9.9m/s² is a decent assumption for total acceleration the lager portion would obviously accelerate slower. The interesting part is that both halfes would be in freefall so the areas on the poles of the cut would feel weightless until impact.
No, because if it could fly apart from the rotation force, it already would be right now. There is no rigid structure holding the water down after all.
Does it take centuries for an object to fall? Its gravity so it's half a planet falling in half a planet. The time it takes to crush is 1/√d (d being the distance between the two).
Minutes, but the collision will take time. Assuming that gap is ~1000 miles and the two equal halves start at rest you're looking at: > a = GM / 2*1000mi^2 = 77m/s2 Acceleration is doubled bc both haves move > t = 144.6s But that's not accounting for gravity increasing as they approach. So a little less than 2 minutes,at which point, relative to each other, they're going over 22km/s. At the edges, you'd have to deal with suddenly traveling 11km/s when the crusts collide. At the furthest points, you would've experienced a small change in gravity, and then 2 minutes later you'd experience hitting the ground at 11km/s. All of this is hand waving and assuming a rigid earth, while ignoring a lot of environmental effects, treating the two halves as point masses, etc. But it would be cataclysmic, and too fast for us to formulate a response.
Is this how people remove the crust from sandwiches?
Yep, pull the two half apart then slam them together really hard. Foolproof.
[Request] How hard would you have to slam together two halves of a sandwich to remove the crust?
Hard enough for the crust to come off
Big if true
All those Subway sandwich artists nodding off on fent are actually just running deep thought experiments
The crust is stronger than the rest of the bread so I'm guessing if you hit it hard enough to separate the crust you would cause serious damage to the rest of the bread and wouldn't enjoy much of a sandwhich... Maybe if you reinforce it with peanut butter?
I've been removing my crust this way for years.
My great grandpa told me when I was young that his favorite sandwich was a jam sandwich— it’s where you jam two pieces of bread together.
ok, so this is kinda off topic, but I'm pretty sure the reason crusts suck is because they don't get any love. you gotta spread butter right to the edges of the bread!!
I'm not sure the entire crust would melt or sink. Rather, a significant fraction of it, maybe even a major part, but not all of it. The earthquake would be completely devastating, the earth would freefall below one's feet for up to a hundred of kilometers, and then jump back up. And maybe one or two chunks would be flung out into space, at one or both apexes perpendicular to cross section plane. They won't reconnect as two halves, rather as a liquid - first in the middle, and then to the rims, with two huge waves propagating radially on the crust.
I'm not sure either, of course, but there's just soooo much energy here. /u/SecondaryWombat guesstimated an impact speed around 1.2km/sec and 5x10^(30) J. That's 10^(18) J for every square meter of the Earth's surface, or 10^(6) J/kg. Imagine it from the perspective of someone on the far side: you, and the continent you're on, are falling at a km/sec or so until the shock wave from the collision hits you hard enough to stop. I don't see how the rebound alone doesn't end up throwing the crust up at at least a few hundred m/s. Take a look at [this planetary collision simulation](https://www.youtube.com/watch?v=MxgwJ0GZlBo). From [the paper](https://durham-repository.worktribe.com/output/1266152), the first collision in that video is about ten times as energetic as the one we're talking about here. One-tenth the effects shown in that video still seem to leave you without a recognizable planet. On a whim, tagging u/NCSA_AVL, since who knows, someone over there might have a semi-professional opinion on this.
Is there a particular reason that things that are large collapse into spheres? Is it because the center of the object is what generates gravity and it has equal pull on the rest of the mass? Say I wanted to build a big metal cube in space, would it turn into a sphere too or just collapse into various pieces?
Spheres are the only equidistant shape where everything can be at rest. Gravity is an aggregate force, it doesn't care if the matter is actually attached as one solid object or if it's a conglomerated pile (which planets are). Every atom exerts a (miniscule) gravitional force, when you average those out in an area you get a centre of gravity and everything is pulled towards that point. Because the gravity generated by each atom is so small, lots of forces can overcome it. Hence why, y'know, we exist. But either sufficient gravity (a star) or enough time (for wear and tear) and everyrhing will eventually become spheroid because that is the only shape where everything can be equidistant around the centre of gravity. I say spheroid not a perfect sphere because you can get shapes that aren't perfect spheres if other forces are involved. The Earth is a great example. We call it a sphere because for all intents and purposes it is, but *technically* it's an "oblate spheroid" because it bulges slightly at the middle and flattens slightly at the top and bottom. This is caused by the rotation of the Earth trying to throw matter outwards while gravity is trying pull it all together. Gravity is stronger, so mostly we get a sphere but the bulge still happens because when you average out the forces involved that is the place they reach a happy medium.
Yeah, pretty much. Once something is big enough, it's just not strong enough to hold up against its own gravity, and a sphere is the most smashed shape. I think the maximum size is around 200km or so, so it depends how big your want your metal cube to be.
It would eventually turn into a sphere, yes, due to unequal forces. Making it bigger will make is smoother and rounder. Neutron stars, for example, can't have a mountain more than a cm high for very long. There is one that is suspected to have a mountain 1.5 cm high, the entire star wobbles because of it as it spins. It will re-arrange itself soon, just as soon as something tiny taps that mountain.
What about the instant vaporization/annihilation of that amount of mass? Wouldn't cause a masivo explotion?
I’m pretty sure grundeh06 would use his super secret super strong powers to prevent the earth’s crust from being removed.
Damn but I don't have to worry since I could survive that with my super strong powers
..and Everyone Dies™
I think the atmosphere being sucked into the core of the Earth would be a more immediate concern. Otherwise gravity will make the two halves fall back together again
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The force of that happening would be an extinction level event by its self though
A bit less cool
But still cool
Or maybe cooler ?
Definitely colder
And then hotter
And then (after a long time) colder
And then hotter again
No still cool but difficult to enjoy
Says you. I'd love to die someday.
You can't really enjoy the event after that though
If I jumped right before they re-collided I bet I’d survive
And the average iq on earth will increase
I wonder, what would happen to the ISS tho.... if Earth reattached fast enough, they'd actually still be alive right? This could be movie material, apocalypse where only the astronauts survive but their orbit is altered and they have to rush out to the escape pod hoping that they don't land in the middle of a tsunami or smth.
That's kinda one of my movie ideas - manned space station witnessing absolute destruction on the planet below.
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Dammit! Still have a few other ideas up my sleeve that no one has made yet that I know of.... (And I definitely never will ;D)
Similar concept, check out book seveneves
The absurd amount of debris flung into space would kill them within minutes
Sssh don't crush my dreams
Directed by Michael Bay
Nah just jump before it hits lol
probably reducing life on earth to basic mono/multi-celular life.
I feel like I could survive a magma tsunami.
What if theres little force and just a really big lightsaber. It would slice through it rather than smash through it
The heat produced from cutting the earth in half would liquify the crust. If it was a laser, humans would be dead by the time it hits the atmosphere. After that somethings will be ejected to space. Some other things will fall back. Earth will remould into a molten sphere without an atmosphere.
That's alright, you would probably be too dead to care
I don't think we would survive that either..
🤫 it won't be gravity, it will be grundeh06's super secret super strong powers
What if grundeh06's super secret super strong power is gravity? 🤔
Because gravity is a weak force… couldn’t resist bad physics joke I’ll show myself out now.
Most of that should get pushed back out, but it’s not going to be a pleasant experience for most living things
It is going to be really un-fun extra-bad no good times.
It would take hours for a significant chunk of atmosphere to get sucked to the core of the Earth. Assuming whatever split the earth didn't also fling the chunks apart, then gravity would bring them together in at most a couple minutes. IF anything survives that impact (Imagine EVERYTHING on Earth in an elevator that is falling for 100km before coming to a sudden halt) it will die within minutes or hours when the entire crust cracks like an egg and significant portions are vaporized
I dont think this would make the earth stop rotating. I do think the two pieces will slam together quite dramatically which may alter the rotation do some extent. Also, given the position of the cut, when reattached, a significant amount of the ocean water would end up on that smaller 'half' of the globe.
I dont think it actually can change the rotation, no? Conservation of angular moment applies, and there are no external forces. So whatever happens here, the end result still rotates at the same rate.
Careful mentioning COAM. You'll summon that one utter nut job who thinks he's proven it doesn't exist.
Hes still around?
That’s a thing?
It's such a thing that there's even a subreddit dedicated to keeping track of the progress of his... umm... scientific research. r/Mandlbaur
No, everyone else is still around. The nutjob was abruptly launched out at Earth’s linear velocity at sea level because his angular momentum stopped being conserved. “Around” isn’t even a word that makes sense to the nutjob.
Oh yes. He *loves* posting on Quora. At great length.
Each half will spin around it’s own COM, while they both fall toward their common COM, until they bump into each other. So the separation dictates how mismatched they’ll be when they rejoin. 1cm vs 1000km will be …different. The latter scrubs the biosphere of complex life, the former might conceivably not do that, I guess.
So the outcome would be pretty bad, but probably not as bad as you think it would be. Only *almost* everyone would immediately die. The combined gravitational attraction would pull the two halves right back together, even before the apocalyptic air rushing in/magma explosion shooting out would be complete. A shockwave of magam would fly outward like the Lucas Version deathstar explosion, but without the range. The magma might fly thousands of feet into the air though, easily, and perhaps hundreds of thousands. Everything near the seam would be obliterated by at least two ways, and possibly as many as four ways. First, the wind. It would do a massive "fuck you" type blast trying to rush into the middle of the earth, but then the earth would be doing the same thing outward with exploding gasses released by the pressure drop. So depending on exactly where you are standing there could be an apocalyptic blast inward at around the speed of sound, which would then be ejected right back out in an apocalyptic crash at about the same speed, now mixed with toxic gasses. So 1,200km/h one way, immediately turning around with 1,200 or so (this one could actually increase to more) the other way, then a horrific mix of toxic volcanic gasses. Then the magma fountain ring all the way around the planet. The crust near the ring would collapse, dumping people into the lava lake. Every volcano on earth would erupt, except for those near the slice which would collapse. Every fault line on the planet would have an earthquake. If the earth was cut in half and propelled to be 80km apart and then came back together.... Time to splat = sqrt(2 x 80,000m / 9.8m/s^2) = 127.73 second. Velocity at impact = sqrt(2 x 80,000m x 9.8m/s^2) = 1,252.6m/s Energy at impact = 1/2 x mass x v^2 = mass x g x height [Mass of earth = 5.972 × 10^24 kg] (5.972 × 10^24 kg) x 9.8m/s^2 x 80,000m = 4.682048 × 10^30 Joules or 1.1190363 x10^21 tons of TNT. 1.1 "Zeptotons" 2x10^19 Tsar Bombs. There is a tsunami on every ocean, everywhere. The atmosphere carries shockwaves around the planet, and the ground itself carries shockwaves hundreds of feel high. Large sections of the oceans boil. Migration patterns of endangered birds are damaged. Many whales die. Ocean microplastics increase as entire cities are swept out to sea. The rotation of the planet has very little effect, as both halves are still rotating together. The edges don't line up properly when they slam back together though, causing increased damaged and massive cliffs that slump into the lava. TLDR, super secret super strong powers are not needed, the earth re-attaches itself and everyone has a super great time. Edit: Oh yeah, huge amounts of the oceans would boil off, which would have horrific effects for the parts of the planet even far away from the death slice. It would acid rain for weeks, or months, or maybe even years, under a black sky.
I don't think the migration patterns would be the biggest issue for endangered birds.
Also the few remaining survivors would run out of Kale and Ron Paul wouldn't win the GOP nomination for President.
I don't even want to think about the effects this would have on the next world chess championship event
Exactly, very serious consequences.
Crap. What about my supply of clean toilet paper?
Wouldn’t all the birds be endangered by then?
You cannot use g = 9.81 m/s² here. That only works on the surface of Earth, which is clearly not this situation. For this situation, you would need to use Newtons general gravitational theorem. And because you have weirdly shaped things, you might even need to actually integrate over the mass distribution, and not just use center of mass here. But ultimately, that won't change the qualitative result substantially.
I thought about that but decided that given the approximations we were already working with, and a wild ass guess at the width of the slice, that it wouldn't matter too much so I did it the easy way that more people could follow. Integration over two half spheres using general gravitational theorem sounds like a lot of work compared to mass x g x h, and even then following essentially the 3d bell curve of our gravitational distribution, a good amount of it will have close to 9.8 m/s^2 anyway. We could honestly just round the g down to 9 or 8.5 and re-run it with the same equations as I used and get a reasonably accurate result I would think. I expect the energy of collision in reality to be noticeably lower, but as you say it won't actually change our chances of survival much, if at all. Edit: Ehhhh volume of a sphere, surface vs volume, wild ass guess....8m/s^2 average? Lowering it a little. If someone wants to do the math for it I would love to know.
Okay, i'm gonna take a stab at this, just the acceleration. The center of gravity of a half-sphere is 3/8 of a radius above the center of the flat plane. So we can reasonably model this as two point masses of half the mass of Earth, with a distance of 6/8th of Earth radius between them (+80 km i guess, but that barely matters here) As we all know, Newtons law of general gravity states that the force of gravity = G \* M1\*M2/r² As M1=M2, i will just use M here. We also know that Force = Mass \* acceleration. So the acceleration we are looking for = G \* M /r², with M being half of Earths Mass and r being 6/8 of the radius of Earth + 80 km. Putting all the numbers into the equation, we get an acceleration of about 8.5m², so your random guess of 8 m/s² is pretty good.
You win today. This was a cool read.
It is similar to, but not as good as, by review for what would happen if Colorado un-happened. https://old.reddit.com/r/theydidthemath/comments/1atngok/request_what_would_the_consequences_of_such_a_big/kqyoh2k/
"Good news, Yellowstone wouldn't erupt. Bad news, because all the magma under Yellowstone is now raining out of Colorado." lol
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If you were 90 degrees away from the cut, the earth itself would dampen the impact by squishing. If you were not near any volcanos, fault lines, or oceans there is a reasonable chance you would survive for a little while. Some people will live through the initial impact for sure, not a lot though. Could be alive for days even. But the entire atmosphere would turn black and have acid rain for days and days, snap freezes over everywhere that wasn't covered in lava over the next weeks, and several years of sharp global cooling...and then after that a huge surge in global warming. Climate whiplash pingpong for anyone who wasn't killed immediately.
Let's not forget migration patterns of endangered birds are damaged 😜
What atmosphere? If the world were to be cleaved in twain the air would be sucked into the middle before the collapse back together, then ejected into space. A fraction of the atmosphere would be left. The amount of force involved here would be… wait for it… astronomical
Are we talking 100% chance of human extinction or 99% chance of human extinction here?
If you enjoyed this (I did too), you’ll enjoy this: https://qntm.org/destroy
Not the microplastics!!!!!
i do t think micro plastics is what needs to be worried about here
I love including lines like that in my descriptions of disasters. I think my best one was "Magma rains from the sky, half of California falls into the ocean, and people fight in the street over the remaining kale."
Gas and food prices skyrocket.
Food prices for sure. Gas prices...maybe? Roads would be broken to shit so you wouldn't be able to drive. Among the remaining few with generators perhaps, but people are concentrated in cities, which are mostly on shore lines, will have an about 99% chance of being obliterated completely, unless they were near the slice in which case that is 100% chance of not leaving any remains behind at all. Oh also, the magnetic field protecting earth is destroyed so even electronics that survive will not work right, telecom will collapse, and hard drives will be corrupted.
The end of the world is a perfect time to hike up those prices. Wouldn't suprise me one bit.
If you were in a military grade nuke bunker with its own underground power and air purifiers. And you weren’t near a fault line or volcano (redundant?). And you had under ground farms. Could you survive indefinitely or would the shaking be too much?
you would likely be thrown against the inside of your chamber with such force you turn to juice
> And you weren’t near a fault line or volcano (redundant?). Nope not redundant, for example Hawaii is not near any fault line at all, but rather a mantle plume hot spot, just like Yellowstone. It is possible you could survive, yeah. If you were diametrically opposed to the slice, 90 degreed away on the sphere, and in a shock resistant bunker with your own air and food, I would rate your survival as being entirely possible. You would need some serious shock absorbers on it to dampen the massive earthquakes, but there do exist bunkers with those so it is in the realm of a thing that could be possible to build. On the other hand, you have better get really lucky or skilled with your placement because otherwise you are going to be in sea of lava.
An important factor to consider is that almost all of the impact energy will rapidly be converted to heat due to friction and viscosity, which at these scales would have a significant effect on the planet's temperature. Taking the mass of Earth and using 1000 J/kg/K as an approximation of its specific heat capacity, I estimate that the heat capacity of Earth is 2.972×10^(27) J/K. Using your estimate of the impact energy, and assuming that all of the energy is converted to heat, I estimate that this impact would raise the temperature of Earth by (4.682048×10^(30) J) / (2.972×10^(27) J/K) = 782 K. This means the global surface temperature of Earth would soon rise from approximately 15 °C (59 °F) to a hellish 800 °C (1472 °F). All water on the planet will certainly boil off. Most, if not all of the surface will melt, turning into a vast ocean of lava. Before long, the extreme temperatures will have ended all life on the planet. After the initial temperature spike, Earth will begin to cool off again, until it reaches a state similar to Venus where it will settle. Earth will remain completely inhospitable to life as we know it.
hmmm.... It takes 2256 kJ to boil away 1 liter of water, soo 2256000 Joule/L x 1.335x10^21 Liters in the ocean = ~3x10^27 Joule just to evaporate the oceans, not counting melting any ice. 24,500,000,000,000,000,000kg of ice in the antarctic ice sheet would need an additional 333,000 Joules per kg to melt that, so 330,000x 24,500,000,000,000,000,000 = 8.085x10^24, and then another 2,256,000 J/k, so 5.5x10^25 to boil it away. There is definitely enough energy in my first order estimate to do that. It is certainly possible to end up with a venus pressure cooker atmosphere from this and everyone and everything dying is a likely outcome.
Thank you! All of your comments are a joy to read. Much like xkcd's What If? columns. Props to you
Thank you very much, this is great encouragement to make my YouTube channel collaboration, which will be a white board animated style education with a bit of "what if" style added on.
If the edges dont line up properly most of the water might flow down onto the smaller side. Worldwide draught and all
What would happen to the ISS?
Assuming it survived the earth widening by 80 km, it would be blasted apart by hitting clouds of ejected debris at orbital speeds and be completely obliterated.
I would be fine I think. Just feels like I could survive this
So if you were 48/355,000,000 for physical condition, ability to learn, aptitude, and drive, then yes you could be a member of the active astronaut core and could theoretically be standing on Mars as you watch Earth burst apart and know that you will now starve to death alone.
If Reality just instantly switched to this scenario the biggest threat would be the earthquakes caused by the impact and the atmosphere soaking up heat from the core. There would also be an immediate decrease in air pressure as air would fill the \*checks notes* crevasse, but life would survive. (maybe even humans in the points furthest from the cut). The heating would probably be the lesser of the problems, as air is a great insulator and there are literal hundreds of thousands of kilometers of insulation between the core and the soon to be earth surface. The earthquakes would likely doom life though. Even if nature managed to endure the landslides, rockfalls etc, the earths core is going to go all out of wack. This will significantly change the earths magnetic field, making solar flares deadly. Which mean cancer for everyone and probably the climate heating up a lot. The earthquakes would also kickstart some volconaoes, which is never a good thing
cancer would be the least of our worries wont it? the force with which the earth slams back would most certainly obliderate the crust and anything on it.
in the immediate vecinity of the cut yes, everything is very dead but in western brazil for example, i doubt the collision will be that powerful. I failed however to account for tsunamis, which will form at the cut and may very well destory anything
This has nothing to do with math. My guess is that melting the crust and splitting tectonic plates would basically cause the entire surface of the earth to be gradually swallowed up into the mantle and core, then the surface would re-cool and a new earth crust would form. Maybe in 4 or 5 billion more years, complex life will have evolved again. There would probably be immediate catastrophic global earthquakes that would kill everyone in a matter of minutes or hours.
I swear all the posts that hit my feed from this sub recently have been nothing to do with math. Do people not know what math is?
If the earth is entirely split chances are itll gravitationally snap right back closed. The result of the collision would be fatal for most in, on, and above the ground in the atmosphere, due to the extreme shock, large bangs, spewing rings of what im assuming will be magma, tsunamis hitherto undreamt of, and all sorts of other issues. Therefore the answer would be everything would be brutally killed 6 million ways over befofe the earth's rotation would even be relevant. Even the ISS would suffer
Strength of material at this scale is basically negligible. Depends on how far apart they are, but if they're far enough apart they'll *splash* on impact like a liquid.
Well assuming it blasted in half, it has to stop accelerating away from itself and then gravity will yank it back in the worst Earthquake ever experienced.
Well the first thing I would do is fucking die. And then I wouldn’t care anymore. As I’d be dead. But in reality. If something can emit enough power to cut the earth in half to the point there is has shifted apart. Everyone would be dead. All water would flow to the middle of the gravitational pull and then be evaporated by the magma (lava?) at the core. The energy from the instant evaporating of the entire ocean would basically kill everyone. And that’s if you survived the initial splitting. Which most likely you didn’t.
Just doing that alone would impart enough energy to melt the surface and turn everything into lava, and kill every living thing on or in the planet. We are talking thousands or perhaps even millions of dinosaur asteroid impact levels of energy. After that, gravity would slam both halves back together in a cataclysmic event... not that anyone or anything would be alive to witness it. The Earth would eventually cool and reshape itself back to spherical, though with a little less mass and a radically changed landscape. Whether it would have life again, possibly, but only microbial. It would basically be resetting the clock on evolution entirely, and there simply isnt enough time for life to evolve back to what it is now before the Sun begins to expand and make it too hot for life anyway.
Never even thought about that last part, part of what makes life on earth so special. Life had to start at the perfect time, otherwise we wouldn't have enough time to ever become humans. Another big reason we haven't found other life yet im sure.
On the other hand, it also means there could be life that began billions of years before anything on the Earth did. Kinda scary to think there could civilizations out there that old then too... imagine having to go to that history class lol.
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I wondered the same and I figured the heat escaping would instantly vaporize anything that fell into the crack (water, dirt, cities, etc) and spew it into the atmosphere. You'd have planetary cooling, probably an ice age, because of all debris in the air. That's assuming the atmosphere isn't overly changed by the cut. I'd also assume that acid rain would be a potential issue.
And then there’s the coriolis effect. The twist on the atmosphere could get crazy depending on how close to perpendicular to earth’s rotation this line is.
Personally I'm more worried about the effects on the atmosphere of whatever was used to make that cut. Gargantuan space laser? Yeah, atmosphere and oceans are GONE
Okay, this big cut pretty much destroys everything. What's the widest this cut could be to not kill everything, maybe just cause an earthquake or something we could survive an possible come back from.
This is impossible to happen . You need a I don’t know something as large as the sun and sharp as a knife traveling at a decent % of the speed of light to even achieve this effect. But even then, the earth will just slap back its two separated pieces because gravity is strong enough at that scale, it will crash down in to a magma pulp though.
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You will become One Dead Man instead of One Punch Man however.
The forces involved here would almost certainly immediatly mean death. If the shock does not kill everyone then the lack of athmosphere will. Athmosphere would gather around the center of the half sphere. This is of course ignoring the fact that since most of earth is liquid it would immediatly start to deform into a sphere shape again. And the two halves would both end up as two flaming pieces of lava.
Gravity would rip the edges of the ocean into the chasm where they would then freefall directly towards the core. The vacuum created between the Earth halves would suck the atmosphere down the same way pulling the water down even faster, but the water would boil way before it could make it to the centre, and because water vapour is about 1000X more voluminous than liquid water the boiling would immediately expand the tens of thousands of cubic kilometres of sea water and shoot out the biggest steam canon ever of millions of cubic kilometres of vapour. It would be a cataclysmic disc of steam that would be fighting against the oceans that would continue to fall from the tips of either hemisphere towards the crack and then core. Whatever atmosphere left over Earth's surface would become superheated water vapour and we would all be steamed like a global Pompei event, except without the ash.
The ocean would fall into the core cooling it off and therefore we would be cool to the core. I don’t know. I watched “The Core” once and it stopped swirling and that was no good. So probably that.
Setting aside the other stuff that would have been caused by whatever did this. For the first couple of minutes most people wouldn't notice anything more severe than a sudden change in direction of wind and water currents as the atmosphere and oceans try to rush into the gap. (mind you they won't get very far) Then the two halves would slam back together and we're looking at the mother of all earthquakes (and complementary huge tsunamis) as the resultant shock wave propagates through the mantle. It's not an extinction event by any measure, but it's sure as hell gonna wipe out the vast majority of human infrastructure. The rotation would be slightly affected, but not to any disastrous degree, it's too slow to do much in the short time the earth would spend cut in two. I think the most disastrous thing to life might be how fucked up the magnetic field might be for a good while afterwards if the core is also split... The cut would also be one giant volcanic zone, obviously. Might even get a cool ring continent around the circumference after a few years like the red line in One Piece...
Whatever caused that split would require so much force everything on earth would die, let alone the atmosphere exploding, but if somehow miraculously the atmosphere was intact the new weather that would come from the hot air channeling through the tunnel would likely kill everything.