Falling to Earth's Core in a Big Blob of Iron 325
Colin Douglas Howell writes "Um...wow. I found this idea via the BBC, (see also the Nature article), but it's really worth reading the annotated paper on the subject. (Gotta love the title.) Basically, you drill a hole in the crust, blast a big crack in it, inject a huge mass of molten iron with a little probe floating inside (made out of material which won't melt or dissolve in the iron), and let the iron mass sink to the core by gravity, carrying the probe with it. (The initial crack grows downward as the iron sinks.) As the probe falls, it sends data back using seismic signals that can be picked up with a gravitational wave observatory like LIGO, but coupled to the ground. Of course, there are enormous problems with the whole thing, but it's still cool to read about. To me, the idea is even neater because it was dreamed up by Dave Stevenson, one of my old professors (and one of the best professors I've ever had). I hope he doesn't mind being Slashdotted. :-)"
And that's how the Earth broke in two (Score:5, Funny)
Alien 4th Grade Class on "History of Stupid Mistakes"
Other 4th Grade Papers... (Score:3, Funny)
More 4th Grade Alien Papers
"A Space Elevator Fell On My Mommy."
"It Turns Out We Need A Magnetic Field."
"My Sister Smells."
Re:And that's how the Earth broke in two (Score:3, Insightful)
Re:And that's how the Earth broke in two (Score:2)
Re:And that's how the Earth broke in two (Score:2)
Expect cheesy and you'll be fine. Have some beers handy and be prepared to laugh at spots that weren't supposed to be funny. You know the drill.
Re:And that's how the Earth broke in two (Score:2)
Crack in the World, 1965, Dana Andrews (Score:5, Funny)
Plot Summary for
Crack in the World (1965)
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Dr. Steven Sorenson (Andrews) plans to tap the geothermal energy of the Earth's interior by means of a thermonuclear device detonated deep within the Earth. Despite dire warnings by fellow scientist Ted Rampian (Moore), Dr Sorenson proceeds with the experiment after secretly learning that he is terminally ill. This experiment causes a crack to form and grow within the earth's crust, which threatens to split the earth in two if it is not stopped in time.
Immortal Dialogue [bluemountains.net.au]
Layperson: What if the crack keeps going - right around the world? What happens then?
Scientist: Where the land masses split the oceans will be sucked in, and the colossal pressure generated by the steam will rip the earth apart - and destroy it.
Layperson: You mean - the world will come to an end!?
Scientist: The world as we know it, yes. As a cloud of astral dust, it will continue to move within the solar system.
[That's what's known as "scientific consolation"....]
Re:Crack in the World, 1965, Dana Andrews (Score:3, Interesting)
Now what's the weakest part of a circle?
Re:Crack in the World, 1965, Dana Andrews (Score:4, Informative)
Their explanation goes to crystalline structures, and stress and loadbearing being a function of surface area. Basically the crack hitting the hole allocates the stress around a much larger unit of area. So the force per area is much smaller than when there is no hole and only a crack. The reduced force per area can then be managed by the material and won't crack further.
Note, the hole must be smoothly finished (you did use the smooth finishing h-bomb and not the rough cut h-bomb) and than there are no more dislocations to start a new crack.
That's my laymen's understanding.
Pretty neat though, the final scene with two moons. THIS MOVIE SCARED THE HELL OUT OF ME!
Re:Crack in the World, 1965, Dana Andrews (Score:2)
Re:And that's how the Earth broke in two (Score:2, Interesting)
Late 70s early 80s there was two extremely dangerous tests: 50 MT underwater by France in Pacific and 100+ MT underground by Soviets on New Zemlya. In second case, despte the fact that under
Dubious (Score:3, Informative)
Can you give me some kind of link or reasoning for this?
Ob. Bob the Angry Flower Reference (Score:3, Funny)
A little cartoon entitled "Yes"... [angryflower.com]
Offtopic? Maybe. Graphically humorous? Hell yeah.
Blockbuster Busts: Come True! (Score:2)
- Seismic Instability
- Hurricane Force Storms
- Monstrous Tidal Waves
- Generally Bad Shit
Well, ok, maybe that won't happen..
Re:Blockbuster Busts: Come True! (Score:2)
Boy I had one of those last week. I had eaten at Taco Bell the night before. Next night I'm driving back home late at night on a rural highway when the little chihuahua wants out. I pulled over and ran into the woods and out came this molten mass that was steamin as it hit the ground. I'm quite sure it's still sinking.
Retro-revenge. (Score:5, Funny)
That's easy for you to say. You already have your degree.
Re:Retro-revenge. (Score:2, Funny)
The end.. (Score:3, Insightful)
There's the problem.... (Score:4, Funny)
Well...thats easy then
Re:There's the problem.... (Score:2)
Well...thats easy then"
Well thats very much do able. The biggest thing that i get thinking is CHECK VALVES, they have better have a good check valve at the top of that hole. Something like oil wells use. Cause i can't think making a man made valcono magma shaft is a good idea.
Or I guess hey lets go nuts, lets start drilling in Newark, NJ
Re:There's the problem.... (Score:2)
Re:There's the problem.... (Score:2)
Re:There's the problem.... (Score:5, Insightful)
That's not quite true. Consider a refrigerator. It consists of an insulator layer and a heat pump. When heat leaks past the insulator it gets sucked back out and dumped.
So you could do the same thing in the earths core, use brick as the insulating layer, and run a refrigerator to pump the heat out, and increase the temperature of the molten iron just outside the insulator. Molten iron is a good conductor of heat, so convection would carry the heat away from the probe.
I must admit I'm more worried by the unbelievable pressure of hundreds of miles of rock, oh yeah, that and the nuclear device they'd need to start off the crack...
Re:There's the problem.... (Score:2)
If molten iron is not a fluid, why do we call it molten? I imagine at the kind of temperatures at the centre of the Earth, molten iron would have very little viscosity, and would convect quite nicely. Of course this doesn't invalidate any of the other points you make ;-)
Re:There's the problem.... (Score:2)
Then I shall eat my hat. I suppose that with iron being such a good conductor, any convection effects would probably be irrelevant in any case.
You'd have to build an unmeltable refrigeration unit for it to make any difference
An unobtanium vacuum flask might do the trick.
Re:There's the problem.... (Score:3, Informative)
Yup. Nothing is 100% efficient. In fact there's a theoretical limit to how efficient it can be which is the Carnot cycle.
So, if we assume the refrigerator starts out at the same temperature as the rest of the probe, its temperature will rise above that of the probe, causing heat to flow from the refrigerator to the probe.
No. The waste heat flows out to the hot iron outside where it is conducted away.
This will cause t
Leave my probe out of this, please. (Score:2)
Re:There's the problem.... (Score:5, Interesting)
Oh I wouldn't worry about that. After the first few miles, the temperature of the surrounding rock would be enough to keep the iron molten. Ever see pictures of lava moving through water? Kinda like that, only instead of being chilled on the outside and kept warm from the inside, it's the other way around.
Besides, if your probe's cooling system is good enough to actually chill several million tons of iron whilest encased in liquid silicate rocks, you could really dispense with the whole molten iron thing and just make the thing dense and massive enough to fall of its own accord and provide it with a heat source to keep the outside piping hot while your magical freon unit maintains room temperature on the inside.
Re:There's the problem.... (Score:3, Informative)
For the coming "hole to China" questions/jokes (Score:5, Insightful)
If you ignore friction, the rotation of the earth, and other "complications", then it would be possible to use this technique to bore a hole right through to China. Imagine the sudden appearence of a tunnel that goes straight through the Earth. If the mass distribution in the earth was uniform (which it is not), a person could jump into this tunnel and then come back up on the surface on the Earth on the other side (China), much like the motion of a pendulum swinging up and down again. Assuming that the journey began with zero initial speed (simply dropping into the hole), your speed would increase and reach a maximum at the center of the earth, and then decrease until you reached the surface on the other end, at which point the speed would again be zero. The gravitational force exerted on the traveler would be proportional to his distance from the center of the earth: it's at a maximum at the surface and zero at the center. If there were no friction, there would be no energy loss, so you could oscillate into and out of the tunnel forever.
Given the physics behind this theorized stunt, boring a hole clear through to China would be impossible. It would require some extra application of force to tunnel "upwards" after reaching the Earth's core.
So no, unlike a Bugs Bunny cartoon, we cannot use molten iron to dig a hole to China. Not like this, anyways.
Re:For the coming "hole to China" questions/jokes (Score:2, Funny)
Re:For the coming "hole to China" questions/jokes (Score:3, Interesting)
Suppose one built a tunnel between New York and Los Angeles that is parabolic. Then, design it with some kind maglev system to reduce friction. Could you then send specially designed cars through these tunnels with a minimum of energy expended?
Maybe you could impart the the car with enough velocity at the beginning so it comes to a gentle stop at the end.
Has someone already done this in Sci
Re:For the coming "hole to China" questions/jokes (Score:3, Informative)
Re:For the coming "hole to China" questions/jokes (Score:2)
Yes, there is a shape of track such that a car released on that track at any point will take the same time to reach the bottom, and it is pretty close to a circular track, but I don't rember what it is called
Re:For the coming "hole to China" questions/jokes (Score:2)
Bull! I don't believe you.
Next you'll be telling that rabbits can't talk!
Re:For the coming "hole to China" questions/jokes (Score:5, Interesting)
However, I think the pesky rotation problem will do you in anyways. Linear velocity at the equator exceeds Mach 1.5; at the exact core it's essentially zero. Dropping down a hole does not magically rid you of that sideways momentum, so you will probably be getting a stone wedgie long before you even hit the mantle. You'd have to stick a rail guide along the side which, since frictionless unobtainium isn't yet in mass production and Hotblack Desiato has first dibs on the stuff anyway, would cause you to lose some of that precious inertia on the way down, thus requiring that you expend power getting yourself up the last bit.
Assuming that I were particularly interested in going to China in the first place, I'll just take a cruise, thank you very much.
Re:For the coming "hole to China" questions/jokes (Score:2)
Admitedly you'd then be travelling from somewhere unpleasantly cold to somewhere else unpleasantly cold, but in theory assuming you could avoid bursting into flames or filling up the whole with magma, that should solve the as you so aptly put it, stone wedgie problem.
Re:For the coming "hole to China" questions/jokes (Score:5, Funny)
is that what you ewre suggesting?
pm
Re:For the coming "hole to China" questions/jokes (Score:2, Interesting)
Re:For the coming "hole to China" questions/jokes (Score:2)
Actually discussing proposition (Score:5, Interesting)
1) Why, instead of using all this iron buisiness, don't we simply use a radioactive ball of goo? This would mean that the whole blob could be a lot smaller as you wouldn't have to worry about maintaining the heat - the radioactivity can do that for you! As well, given that melting point increases proportionally to pressure, and that the pressure in near the earth's core is extremely high, you don't have to worry about getting the iron hot enough to not worry about that. The guy writing the paper does mention the possibility of using nuclear, but he doesn't give any good reason why not.
2) Nice quote - "The correct application of this energy to open up a crack and the technological challenge of emplacing the iron should be much less challenging than the manhattan project." He does realize how difficult the manhatten project was, doesn't he?
3) He mentions that the hole would not completely close up behind the probe (NB - this would not cause a volcano, for reasons he points out, mostly due to tube size and geometry). Why is this the case? does some of the matter get combusted into a gas and escape out the chimney? or is there something else here that makes this not violate the conservation of matter? On another thought, would it be possible to lower a second probe down this chimney?!
4) The sensor package he discusses would look for temperature, pressure, trace + major elements, and electrical conductivity, etc. I can understand the pressure bit, but wouldn't the temperature and element sensors only be sensing the iron casing that the probe was injected with? unless he has some other method of sensing these things at some distance away from the probe I don't see how this is possible (maybe trace elements mixed with iron on the way down, but the experimental error in this would be huge). On another note, using the nuclear probe proposal in point 1, could it be possible to moderate the nuclear reaction and thus stop the probe for a bit, do some sensoring (whatever that may be, and I know I made that word up) and geology, then start up again? Also, this would be valuable for point 5...
5) He mentions that we don't know much about working with seismic waves. Wouldn't all this iron buisiness and the fact that its fluid potentially cause problems with the seismic signal? (like distortion, etc) Given that we haven't done much encoding/modulating, and transmitting of data using seismic waves, it might be a good idea to perfect this first. The only other option I could see would be emitting a constant signal and watching how it varies as the probe descends, and then extrapolating this for data (of course, then you don't get the juicy data at the probe itself).
There's more I could think of, but I do want to get this out, and I've got other things I should be doing. All the same, the article was an interesting read and stimulated the brain cells fairly well, even if it is completely impossible!
Re:For the coming "hole to China" questions/jokes (Score:2)
Not quite. Gravitational force is relative to the distance between the two bodies, but it gets STRONGER as those bodies get closer. Hence Ecuadorian mountain people "weigh" less than people in Death Valley.
In the theoretical tube through the Earth, there would be a sort of reverse LaGrange point somwehere in the tube, where the prox
Re:The Hole Will Close Back Up... (Score:2)
Fisrt message (Score:2)
also, you better hope that nobody misplaces adecimal in te controls to create seismic disturbances. Earthquakes, volcanos, and other shit hollywood likes to make bad movies about.
This will never work (Score:2, Insightful)
This will never work. Its pure pop science, and the CalTech should revoke this guys tenure, if he has any.
Worst. Idea. Ever.
Re:This will never work (Score:3, Funny)
Please to meet you. I'm the pope.
This will never work.
Gee. Do you think? Funnily enough most people here know that this idea is just a cartoon sketch of an idea; a bit of brainstorming, but apparently you don't.
Its pure pop science, and the CalTech should revoke this guys tenure, if he has any.
You obviously want his job. Anyway enough wasting time with you, I've got eclesiastical matters to deal with.
Re:This will never work (Score:2)
The sense I got from his interview on NPR was that this was just an 'interesting idea' he was throwing out, not something he was planning to try six months from now. Also, if having one far-fetched idea was grounds for revoking tenure, I suspect we'd have very few professors left.
Re:Gee (Score:2)
Oh, and using not-so depleted uranium, we could start a chain reaction in the stuff and the liberated incidental antineutrino pulses could be picked up by the existing neutrino detectores, as they have been doing with nuclear reactors already. No need for the proposed gravitational dectector signalling. All we need for this is the entire mass of Iraq uranium (a
Blob of Iron? More like a slashdotted server (Score:5, Funny)
The slashdotting the server will receive ought to help melt it and the floor beneath it.
Off goes the server, down, down, down
Are they sure this will work? (Score:2, Interesting)
Why not use cracks already here? (Score:2, Interesting)
Re:Why not use cracks already here? (Score:3, Funny)
You want to send a probe down.
See the problem?
Scientist,"Ok, now we'll just head on up to the vent over there and toss the probe in.."
*Rumblings from volcano*
Scientist, "I can't help feeling that I've missed something crucial in my calculations... oh well."
*scientist continues to the edge of the vent, tosses probe in*
Scientist (excitedly),"Right! Now all we do is wait for some data! (Taps laptop) Hmm, there must be a sensor probl
A wireless probe? (Score:5, Funny)
Re:A wireless probe? (Score:2)
Re:A wireless probe? (Score:2)
Oh and the high powered laser beams bouncing back and forth inside:)
Hmm (Score:2, Funny)
It'll never work... (Score:2)
Re:It'll never work... (Score:2)
It's like claiming that cows are more buoyant than air, and they're only held down by the force of the sun's rays bombarding them.
Re:It'll never work... (Score:2, Funny)
The big question is - (Score:5, Funny)
Totally ignoring the *real* problem (Score:5, Insightful)
I'd be more worried about the device being able to withstand that pressure. I fail to see how surrounding the probe with molten iron (or any other fluid, for that matter) will prevent the weight of the planet from squishing it like a bug. Or does he plan on violating the laws of physics at the same time?
Re:Totally ignoring the *real* problem (Score:3, Funny)
Re:Totally ignoring the *real* problem (Score:3, Informative)
Re:Totally ignoring the *real* problem (Score:2)
That's an interesting point, but perhaps not a fatal one.
The pressure at one mile down is quite high, but we have mines that go that deep and deeper, so therefore we can build supports that can withstand the load. On the other hand, pressure at the center is exactly zero, so there must be some penetration depth of maximum pressure, with pressure diminishing
Re:Totally ignoring the *real* problem (Score:3, Informative)
If I remember correctly, the radius of the earth is about 3600 miles.
"On the other hand, pressure at the center is exactly zero,"
No, because the surrounding fluid still wants to be at the center and still transmits the weight of all the above fluid to the center. The center of the earth is where the pressure will be at it's greatest, which is wh
Re:Totally ignoring the *real* problem (Score:3, Interesting)
Yes, they are. It's just negligible in most real-world situations. Going miles under molten rock doesn't fall into the "real-world situation" category, though.
But even if this probe were going down in a blob of uncompressable molten unobtanium, Pascal still says that the pressure within the blob is the same as the pressure outside the blob.
"Furthermore, if you made the probe a solid sphere, it'd also be pretty much indestructible."
Ignoring the problem of making sure it
Old SciFi movie... (Score:2)
Re:Old SciFi movie... (Score:2)
Yep that's the movie. (Score:2)
Um, hello? (Score:4, Funny)
One big problem (Score:5, Funny)
Re:One big problem (Score:5, Funny)
humor? what? (Score:2)
Geek courtesy (Score:2, Insightful)
Hint- ask, next time. I don't care if it's editors or story submitters, if the site doesn't seem like it'll take it(ie, it's not a big-fish site), or if it's a nonprofit, ask first.
This ain't "news for nerds", it's "linkage with discussion", and it is pretty embarassing that slashdot STILL doesn't bother to do jack about the problem, simply hiding behind a few pathetic excuses in the FAQ about it being "too complex", whcih is complete bullshit; look at how compl
sorry for being off-topic, btw (Score:2)
Meant to put this in right at the top, but for what it's worth, an apology for rehashing what's somewhat of an old topic, and for being off-topic. And coming off as too cranky :-)
I hope I have at the least added something new, and request only that people mod with care- don't just slap it in any direction(UP or down) with a knee-click reaction.
Re:Geek courtesy (Score:2)
when professors run out of ideas... (Score:2, Funny)
Mental Exercise (Score:2)
Great idea. It should work. (Score:4, Interesting)
I think the biggest problem will be the earths crust. Where can we find or drill a hole large enough vertically straight?? Hawaii?? Mount Fuji should be a better place but do we really want to drill a hole in that given its history?
And finally the idea that most of the space under the crust is molten mantle is still just a theory. Maybe 100 meters down the iron will just sit on another mass of rock that just happens to be there. And I dont know how will it find and go through cracks. If like water its allowed to drain, it will spread thin enough to damage the probe, so LOTS and LOTS of molten iron should be used on a vertical shaft like mount fuji.
I think radio waves of the right freq can travel within the mantle, so we could have large satellite dishes pointed into the ground. Heck we could even send bombs to China. Designer earthquakes!
Re:Great idea. It should work. (Score:2)
The advantage of Hawaii is that the hole is already there, open, and has been for a decade or two now. As long as you can handle the upward current, just drop the thing into the Pu'u O'o Vent and be done with it.
Old news. (Score:2)
And Everyone Thought (Score:3, Funny)
A solution for our nuclear waste? (Score:2, Insightful)
Sounds like... (Score:3, Funny)
Data? What data? (Score:5, Interesting)
What kind of information about its surroundings could the probe pick up from inside all that molten iron?
Re:Data? What data? (Score:2)
Heat and pressure...you know...the things that typically melt probes here on the upper crust.
Re:Data? What data? (Score:3)
Maybe I'm misunderstanding, but wouldn't the probe, encased in iron, find that somebody stuck quite a bit of really hot, compressed iron down there.
And wouldn't the probe, most likely not being as dense as the iron, reach a pressure point where it would float and/or be crushed? i.e. stuck in the crack while the iron continues down.
testing this idea (Score:2)
Oh, yeah. That'd work. (Score:2)
Except, how big a bomb would we need to re-melt the moon's core? It's been frozen for a few billion years now...
Ok, I'm worried now (Score:2)
A nuclear blast on the surface has proven to be done with minimal global harm, with the exception of radiation and minor fallout of radio active isotopes that humans are generally not exposed to, some found in nature... or rather, those dead places where no shit grows, some with a really short half life generally not something you'd want in your hair
Under ground testing has been done with minimal impact on the globe, just some radia
product placement for AMD (Score:2)
I Hope This Project Goes... (Score:2)
...straight to Hell. :)
How much for a ticket?? (Score:2)
Crack in the earth ... Stupid idea? (Score:2)
Re:You were only supposed to blow the bloody doors (Score:3, Funny)
Gravitational fields reversing? What, can we expect to start falling into the sky any day now?
Re:You were only supposed to blow the bloody doors (Score:2, Informative)
Re:isn't this a bit risky? (Score:4, Informative)
The Earth has three layers:
* The crust (outermost)
* The Mantle (middle)
* The core (innermost)
The Mantle is mostly viscous liquid. The blast would be diffused into the liquid. Considering how much heat energy is in the magma at any given moment, a nuclear blast will have a negligable effect.
Volcanos are caused by magma (the top layer of the Mantle) seeping out of a crack in the crust. Blasting the core would not affect the crust at all.
The crust is separated into plates called tectonic plates that "float" on the Mantle.
Most earthquakes are caused by slipping in the tectonic plates.
Again, since the blast's energy will be negligable to the energy in the mantle, so there will be little flucuation in the mantle's energy to cause waves in the mantle.
Re:isn't this a bit risky? (Score:4, Informative)
One part of the mantle, the asthenosphere, has a tiny amount of melted rock due to the pressure & temperature regime at this (100 - 200 km) depth, but melt is only on the order of 1% of the material here -- it just sort of coats and lubricates the mineral grains. The asthenosphere has little effective strength compared to the geodynamic forces it encounters, but it's far from liquid.
As long as I'm here: no, magma is not the top layer of the mantle, and furthermore a lot of magma does not have a mantle source (although a lot of magma does depend on mantle processes).
The rest of the mantle is believed to deform plastically, but it is not a liquid. It is composed of coherent solid crystals. This is very hot rock, but it is also under extreme pressure, and the crystalline phases that exist here are stable. Over long periods of time this material deforms like stiff putty.
As for detonating a bomb in the mantle, if you managed to figure out some way to do so...Yes, it would create seismic waves just like a bomb not detonated in the mantle would. Let us review: the mantle is solid coherent rock. But then again it's not as if that is even relevant because sound waves are very effectively transmitted through liquids as well as solids. That's why depth charges are used to kill submarines. Granted, shear waves do not pass through liquids, but pressure waves do. NOTE: unlike water, shear waves do pass through the mantle because the mantle is solid.
Seismic waves are received every day at seismometers around the world, originating from earthquakes all over our planet. Much of what we know about the deep earth has been inferred using these seismic waves. Again, the point is sound moves very readily through the solid mantle.
You did manage to get one thing right: plates do float on the mantle in every sense of the word. Continents in particular are just low density scum floating on a sea of high density mantle rocks.
You were also on the right track in regard to earthquakes occurring in plates, but I should add that earthquakes do not typically occur in the mantle because mantle rocks are so hot and under such high pressure, that when stressed they shear and deform plastically rather than fracturing and causing an earthquake. This property doesn't, however, prevent the propogation of earthquake waves through the mantle (see above), nor does it prevent the creation of earthquake waves when the hypothetical bomb causes a large and rapid change in the localized pressure regime.
- Anonymous Coward
Re:The scientist was interviewed on NPR. (Score:2)
Any silicon-based electronics to function, that is. Diamond semiconductors would work, although I'm not sure how he plans to power them. A temperature difference would vanish immediately, especially with primarily diamond construction.
I don't know how he plans to implement a seismic transponder either - since any ferrous metal would be liquid, ruling out electromagnetic vibration, I guess you'd have to use explosives.
Re:The scientist was interviewed on NPR. (Score:2)
Just because iron insode the probe would be molten doesn't mean you couldn't use a titanium solenoid to magnetically move a large molten iron mass inside the probe back and forth to generate seismic waves.
Most missles use pirotechnic devices to melt their batteries' electrolytes. They're called thermal batteries and give a lot of power for a given weight and volume... plus the shelf li