If you cut the planet in half...what would happen?

Plazaman

Irish Guitarist wrote: »

Each half would regenerate, making two planet Earths.

Begs I on the top one.

No but seriously, the electromagnetic field surrounding the earth would be disrupted to such an extend that the human brain would be fried whilst animals - specifically sheep, would become the dominant species of the planet. And in a couple of generations, there would be uproar as there would be horse dna found in their human lasagnes.

Richard Dower

for those wondering, I envisage a surgical like cut, pinpoint clean through the middle.

juan.kerr

OP, where would you be during all this?

igorbiscan

Ha ha,, op, your thought process is wasted on boards.ie, this belongs with the classics like "the illiad" "ulysses"and platos "can you cry under water?" volume 2 ...

juan.kerr

igorbiscan wrote: »

and platos "can you cry under water?" volume 2 ...

you can urinate under water anyway. Just ask a swimming pool attendant.

witty username

Capt'n Midnight

It depends on how far apart you separate the halves by.

If they are a gnats whisker apart then we might not even notice them joining together.


If they are further apart then it would be earthquake central and lots of aftershocks and we'd all die. A lot of the energy would transfer to the surface.

Or if you move them far enough apart then they could orbit each other.
But the moon would probably get ejected.

life on the two halves would not be good, as a rough rule any body over 600km in diameter will collapse under it's own weight into a spherical body. you could work out the amount of energy released by the amount of matter from mgh and show that things would hot up pretty much.

the culture of deference

Sounds like an Austin powers plot.

The atmosphere and magnetosphere would be destroyed instantly.

A molten Nickel Iron core is about 5400 C

The Big Red Button

Richard Dower wrote: »

for those wondering, I envisage a surgical like cut, pinpoint clean through the middle.

But which middle? The Equator middle, or Pole-to-Pole middle?

(Middle. One of those words that sounds odder the more you say it!)

Roger_007

the culture of deference wrote: »

Sounds like an Austin powers plot.

The atmosphere and magnetosphere would be destroyed instantly.

A molten Nickel Iron core is about 5400 C

Should I leave my washing out on the line or take it in?

AlmightyCushion

Capt'n Midnight wrote: »

life on the two halves would not be good, as a rough rule any body over 600km in diameter will collapse under it's own weight into a spherical body.

I don't know any body that big and I imagine any body that big is already pretty spherical.

Capt'n Midnight

AlmightyCushion wrote: »

I don't know any body that big and I imagine any body that big is already pretty spherical.

Like yo mamma

AlmightyCushion

Capt'n Midnight wrote: »

Like yo mamma

Oooo snap!

http://24.media.tumblr.com/tumblr_m4ifbmql1v1qfw2dno1_250.gif

Kev.OC

Richard Dower wrote: »

for those wondering, I envisage a surgical like cut, pinpoint clean through the middle.

When you say surgical cut, do you mean at a personal or planetary scale. If you cut me with a scalpel I'll feel it. If you cut something as big as a planet with a scalpel, nothing will happen. The two halves will have fused together before you get a mile down the road.

Also, you can't cut a liquid in half, but we'll ignore that for the sake of argument.

Now, if you had a GIANT laser that cut a channel through the planet that was, say, 10 miles across, well then that might make things interesting. Gravity would still probably pull the two halves together though.

Another big area is energy transfer. I imagine a laser bisecting the Earth would generate a significant amount of heat in the surrounding area. Would this heat be enough to vaporize any atmospheric and water molecules it comes across? Quite possibly. That could be problematic for us.

tl;dr: Surgical cut; nothing would happen. Clean cut measuring several miles across; problems arise.

BBDBB

Kev.OC wrote: »

When you say surgical cut, do you mean at a personal or planetary scale. If you cut me with a scalpel I'll feel it. If you cut something as big as a planet with a scalpel, nothing will happen. The two halves will have fused together before you get a mile down the road.

Also, you can't cut a liquid in half, but we'll ignore that for the sake of argument.

Now, if you had a GIANT laser that cut a channel through the planet that was, say, 10 miles across, well then that might make things interesting. Gravity would still probably pull the two halves together though.

Another big area is energy transfer. I imagine a laser bisecting the Earth would generate a significant amount of heat in the surrounding area. Would this heat be enough to vaporize any atmospheric and water molecules it comes across? Quite possibly. That could be problematic for us.

tl;dr: Surgical cut; nothing would happen. Clean cut measuring several miles across; problems arise.

you emphasised the wrong word dude!

let Dr Evil show you the way
http://static3.businessinsider.com/image/4db58b2949e2aece0d030000/dr-evil-airquote.jpg

oden

If you use a laser to cut the op's head in half you might get some sort of decent thread, or maybe not. Dumbass

Capt'n Midnight

AFAIK the energy needed to split the planet is about the same as needed to remove all the electrons from 1Kg of copper.

crockholm

The globe making industry would decline, possibly offset by an employment boom in the cross-section industry

Roger_007

Could you still go on a round-the-world-cruise?

FGR

Why not just shoot right through the earth and have a tunnel running from Ireland to the other side..If it's land mass and not some part of the pacific waiting that is.

Hop in one side and appear out the other..Or be torn apart in the middle by gravitational forces/melted by the intense heat.

Branch Meeting

Something similar to a Cadbury's cream egg. How do you eat yours ?

dttq

Richard Dower wrote: »

Lets apply science fiction to science fact here....lets assume you had a space based laser, massively powered.....it shoots out a straight beam and slices through the Earth.....what would happen?

Would the two halves break apart and float away?...would everyone get killed

Dr Evil, that you?

saabsaab

Interesting thought experiment. Lazer would be a narrow cut and gravity would pull it back again so as some others said nothing would happen.:D

Senna

Before you attempt this we should line up all the Siamese twins along the cut line.

ejmaztec

Lionel Messy wrote: »

Cold War II

A game of two halves.

Sofiztikated

As soon as the laser penetrates the earths mantle, it'll go

"Pffffffffffffffffffffffffffffffffffffffffffffffffffffffffssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssshhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhtttttttttttttttttttttttttttttttttttttttttttttttttttttttttttt" and fly around the Milky Way, before finally ending up in that hard to reach place behind the TV.

7ofBrian

Ever seen a cross section of a gobstopper?

Lelantos

FGR wrote: »

Why not just shoot right through the earth and have a tunnel running from Ireland to the other side..If it's land mass and not some part of the pacific waiting that is.

Hop in one side and appear out the other..Or be torn apart in the middle by gravitational forces/melted by the intense heat.

So you're the guy responsible for Colin Farrell's Total Recall, I hope you're ashamed of yourself!

Richard Dower

chatterpillar wrote: »

But which middle? The Equator middle, or Pole-to-Pole middle?

(Middle. One of those words that sounds odder the more you say it!)

Top to bottom, so pole to pole I guess. The laser platform would be quite a distance from the planet. Not putting a figure it on, and as for heat from the laser....we're putting science fiction and trying to apply science fact.....so its a highly advanced laser capable of cutting through a planet....so it generating heat is mute

Richard Dower

Kev.OC wrote: »

When you say surgical cut, do you mean at a personal or planetary scale. If you cut me with a scalpel I'll feel it. If you cut something as big as a planet with a scalpel, nothing will happen. The two halves will have fused together before you get a mile down the road.

Also, you can't cut a liquid in half, but we'll ignore that for the sake of argument.

Now, if you had a GIANT laser that cut a channel through the planet that was, say, 10 miles across, well then that might make things interesting. Gravity would still probably pull the two halves together though.

Another big area is energy transfer. I imagine a laser bisecting the Earth would generate a significant amount of heat in the surrounding area. Would this heat be enough to vaporize any atmospheric and water molecules it comes across? Quite possibly. That could be problematic for us.

tl;dr: Surgical cut; nothing would happen. Clean cut measuring several miles across; problems arise.

The width of the actual cut would be I guess equal to the wavelength of the laser, for this discussion it would not be metres or even inches....it be nm.

Richard Dower

Monsieur Folie wrote: »

Well due to gravity I find it highly improbable that the two pieces would just float off. I guess it would largely depend on how thick the cut was. if it was a thick enough cut and then gravity brought the two halves smashing back together, there would probably be some catastrophically large earthquakes. Hopefully xkcd will address it; this is exactly the kind of questions he deals with! :P

Cheers!....I could have made it easy by saying the cut was miles in length, or even metres.....but I think it more interesting if it was a laser scalpal type cut, nano meteres across.

Paul1990

You're cutting down the middle, what happens to all the water?

Would it just fall off the edge of both halves of the planet? Like a huge temporary waterfall that falls into space?

7ofBrian

Presumably cutting through the centre of the planet with a laser would remove the magnetism of the iron core due to the intense heat of the laser, thereby making useless any polar based navigation equipment.
Also destroying the core would also destroy gravity so everything would probably float off into space.
Although the heat from the laser would also vaporise the atmosphere so we would all be dead anyway.

Capt'n Midnight

Richard Dower wrote: »

The width of the actual cut would be I guess equal to the wavelength of the laser, for this discussion it would not be metres or even inches....it be nm.

or less if you used interference

and you can always use UV lasers or X-Rays


hmmm...

A quasar is like a giant scythe emitting a beam of X-Rays and high energy particles from it's poles like an enormous light sabre, more powerful than the entire output of the milky way galaxy , maybe up to a thousand times more powerful


defo enough energy to slice the planet in two , possibly enough gravity to keep the two halves from joining again

Bad Santa

You'd get in a lot of trouble.

BizzyC

But wait, wouldn't the gap to close immediately as the hole was being cut?

If you cut through the crust, magma comes out, solidifies and new rock is formed....

You'd end up with a ridge-ring of volcanic rock around the earth.

bazza1

you would have to pay two proprty taxes! :eek:

hatrickpatrick

Unless you have some way of also causing some opposing energy between the two halves, gravity would quickly bring them back together. That's how planets form in the first place after all.

You'd have a very nasty crash between the two halves though. You'd effectively have created a gigantic fault line going through the entire planet, so there would be gargantuan earthquakes which would probably affect every part of the planet. You'd also be exposing the mantle at the points where the laser sliced, so depending on whether there were any hot spots under those areas, you'd almost certainly cause some absolutely monstrous volcanic eruptions.

Bipolar Joe

I wonder if the direction of the cut would matter, like is it along the equator or from true north to true south. Also, would the gravity at the center of the Earth bend the laser? I think that happens sometimes because science.

I think if you managed it EXACTLY, and got two halves with the exact same density or whatever, the two halves would hold together because of the gravity from each other. It would have to be some insane small width, like in the picometer range, something that's thinner than a single atom.

Akrasia

7ofBrian wrote: »

Also destroying the core would also destroy gravity so everything would probably float off into space.

It would do the what now?

Akrasia

You all thought I was mad when I bought that life sized paper mache model of the earth from that pinky and the brain episode, but you're not laughing now, are ye.

chakotha

Gravity would cause both hemispheres to close the cut and crunch back together as soon as the laser had passed - like a broken zip.

BrensBenz

Is this an Irish laser? If so, the Healy Raes would insist that the laser was driven by a drunk and, consequently, it would miss Earth altogether and blow lumps off Betelgeuse. Then they would claim compo and build a tourist centre if any of the lumps made it back to Kerry.

Better off practicing your lasering on the moon first. "Sure it's doin nawhin up dayer."

Capt'n Midnight

chakotha wrote: »

Gravity would cause both hemispheres to close the cut and crunch back together as soon as the laser had passed - like a broken zip.

Not if they were in the Hill Sphere of the aforementioned quasar.



As an aside, if the two halves didn't collapse into spheres it would set navigation by ship back many years. GPS would be affected and there would exist the very real danger of sailing off the edge of the world.

ScumLord

A laser doesn't really cut in the traditional sense either. It burns things away through heat. I suspect when the laser hits the earths core it will become completely ineffective as the core would be as hot. I would think a laser would have difficulty going through rock too.

If you could cut through the crust it would cause some serious earthquakes and volcanoes but you couldn't do any serious damage to the planets structure.

Mal-Adjusted

if this were to happen, then all the water on the earth's surface would instantly rush into this new chasm and probably be turned to steam. the magnetic field would collapse due to the core no longer rotating. Gravity would sooner or later pull the two halves back together and it'd end up looking like the moon.

Capt'n Midnight

Mal-Adjusted wrote: »

if this were to happen, then all the water on the earth's surface would instantly rush into this new chasm and probably be turned to steam. the magnetic field would collapse due to the core no longer rotating. Gravity would sooner or later pull the two halves back together and it'd end up looking like the moon.

water doesn't run uphill

the centre of gravity of a hemisphere is 3/8th's from the bottom so the edges are now further away from the centre of gravity than the centre

ScumLord

Mal-Adjusted wrote: »

the magnetic field would collapse due to the core no longer rotating.

Would that happen though. If a very powerful laser made it's way to the liquid core it might only heat it up more encouraging the rotation. I just think that once the laser gets to the core all it will be doing is heating it up the same way pointing a laser into water would just heat it up.

the keen edge

Gravity wouldn't be destroyed; it usual observed effects would only be temporarily disrupted prior to re-balancing.
The earths magnetic field may be destroyed; although it could possibly resume on the new formations.

The unimaginable chaos that both the cutting and separation would generate means that it's a pointless exercise debating the details.

Its doubtful that even the worlds most power computer could even attempt modelling such an chaotic event.

OneOfThem Stumbled

Richard Dower wrote: »

Lets apply science fiction to science fact here....lets assume you had a space based laser, massively powered.....it shoots out a straight beam and slices through the Earth.....what would happen?

Would the two halves break apart and float away?...would everyone get killed

To answer your question:

Supposing that nothing was used to cut the Earth in half (a giant cheese wire!), then, nothing much.

When I say nothing much; you'd have the equivalent of the worst imaginable earthquakes all along the division as the halves momentarily split, before being dragged back together by the force of gravity. Cue lots of shaking, tectonic movement, volcanoes, etc, and more than likely a number of massive tsunami.

But besides the destruction and death, things should be back to normal by tea-time.