1944: "The End of the Rainbow"

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Mfraser
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Re: 1944: "The End of the Rainbow"

Postby Mfraser » Sat Jan 20, 2018 3:05 pm UTC

New member, didn’t :lol: see this comment, but -
Mass of the oceans - 1.4x10^21 kg
Mass of Au in the sun - 10^20 kg

Don’t let facts get in the way of a good comic, I say :)

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gmalivuk
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Re: 1944: "The End of the Rainbow"

Postby gmalivuk » Sat Jan 20, 2018 10:04 pm UTC

Mfraser wrote:
New member, didn’t :lol: see this comment, but -
Mass of the oceans - 1.4x10^21 kg
Mass of Au in the sun - 10^20 kg
A few others have already derived much higher quantities than that. Where are you getting your information?

paha arkkitehti wrote:
niky wrote:A sextillion tons of gold.

You could bankrupt every country on Earth a million times over by dumping that amount into the economy.


Only because the physical weight of all that gold is enough to _crush_ the economy. And everything else on Earth.
To be fair, the amount of gold in Earth's own core would do that job fairly well, too. (It wouldn't crush *everything* because it'd only be 4 meters or so, but it'd kill anyone out in the open and crush most buildings, for sure.)
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hamjudo
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Re: 1944: "The End of the Rainbow"

Postby hamjudo » Mon Jan 22, 2018 3:27 pm UTC

gmalivuk wrote:To be fair, the amount of gold in Earth's own core would do that job fairly well, too. (It wouldn't crush *everything* because it'd only be 4 meters or so, but it'd kill anyone out in the open and crush most buildings, for sure.)


I am having trouble imagining a core mining technique that would leave anyone alive.

Long before the gold layer is a millimeter thick, the waste heat from the mining system will boil away the oceans, unless the mining process is slow enough to get the heat off planet without killing us. Even a micron per year would probably be deadly.

I am going with the overly charitable assumption that if we have a way to separate gold from the other elements in the Earth's core at a global scale, we can do it without releasing any chemical wastes.

The surface area of a borehole down into the top of the liquid core is proportional to the radius, whereas, the cross section available for the extension cord and coolant tubes goes up with the square of the radius. This means it is theoretically possible to drill a hole that far while installing, maintaining, and powering an actively cooled well hole casing.

Before we can calculate the size of the whole we need, there are a few assumptions that need to be made:
Is diamond the best material for the casing?
Can we use a coolant loop embedded in the casing, or do we need to continuously sweat something across the whole surface to maintain a layer of boiling coolant between the casing and the Earth's liquid core?
Which coolant do we use for the coolant loop that keeps the outer casing from melting?
How much of that coolant do we need per square meter of casing surface per second?

gimmespamnow
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Re: 1944: "The End of the Rainbow"

Postby gimmespamnow » Tue Jan 23, 2018 1:59 am UTC

GlassHouses wrote:
paha arkkitehti wrote:
niky wrote:A sextillion tons of gold.

You could bankrupt every country on Earth a million times over by dumping that amount into the economy.


Only because the physical weight of all that gold is enough to _crush_ the economy. And everything else on Earth.

And even if one were to deliver a fraction of the gold from the sun to Earth, small enough that it didn't crush everything but large enough to dwarf the gold reserves we already have, what would the economic impact be?

The price of gold would tank, obviously, and that would cause hard times for people in the gold production business, but since the value of money has nothing to do with the price of gold, everything else would keep humming along just as before. And we could congratulate ourselves on the wisdom of those who came before us and decided to end the "gold standard." 8-)

It would still have a lot of impact. If you could get enough to get the price down to the same price as copper, think of what it would do to electronics or roofing or plumbing, (because it doesn't oxidize,) and it would also replace depleted uranium in weapons and sailboats, (high density.) Monster cable would be no more, because gold plated coat hangers would be available at the dollar store...

Mikeski
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Re: 1944: "The End of the Rainbow"

Postby Mikeski » Tue Jan 23, 2018 2:02 am UTC

hamjudo wrote:
gmalivuk wrote:To be fair, the amount of gold in Earth's own core would do that job fairly well, too. (It wouldn't crush *everything* because it'd only be 4 meters or so, but it'd kill anyone out in the open and crush most buildings, for sure.)

Before we can calculate the size of the whole[sic] we need, there are a few assumptions that need to be made:
Is diamond the best material for the casing?

Don't bother with questions past this one; you'll need some sort of magical unobtainium to hold a hole to the core open against earth's own gravity, never mind the heat.

hamjudo
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Re: 1944: "The End of the Rainbow"

Postby hamjudo » Tue Jan 23, 2018 2:59 am UTC

Mikeski wrote:
hamjudo wrote:
gmalivuk wrote:To be fair, the amount of gold in Earth's own core would do that job fairly well, too. (It wouldn't crush *everything* because it'd only be 4 meters or so, but it'd kill anyone out in the open and crush most buildings, for sure.)

Before we can calculate the size of the whole[sic] we need, there are a few assumptions that need to be made:
Is diamond the best material for the casing?

Don't bother with questions past this one; you'll need some sort of magical unobtainium to hold a hole to the core open against earth's own gravity, never mind the heat.


For this project to have a chance, the entire assembly has to operate at the local pressure and each section will have to maintain neutral buoyancy. The coolant will need to be roughly the same density as molten iron at that pressure. Molten iron makes a lousy refrigerant. It really helps to have phase changes at convenient temperatures.

Materials behave differently at those pressures. Hopefully, there are superconductors at that pressure range that can carry significant current.

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Wee Red Bird
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Re: 1944: "The End of the Rainbow"

Postby Wee Red Bird » Tue Jan 23, 2018 4:43 pm UTC

hamjudo wrote:
gmalivuk wrote:Long before the gold layer is a millimeter thick, the waste heat from the mining system will boil away the oceans, unless the mining process is slow enough to get the heat off planet without killing us. Even a micron per year would probably be deadly.

Do you really want to vent the heat off from the Earth's core? It would probably be best to try and keep it down there rather than risk the core cooling down.
Instead of venting while trying to cool down equipment, perhaps preventing it heating up would be better. Find some way to repel the heat. Probably something akin to a shield from Star Trek to deflect heat away and not something we have on hand at the moment.

hamjudo
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Re: 1944: "The End of the Rainbow"

Postby hamjudo » Thu Jan 25, 2018 12:13 am UTC

Wee Red Bird wrote:
hamjudo wrote:Long before the gold layer is a millimeter thick, the waste heat from the mining system will boil away the oceans, unless the mining process is slow enough to get the heat off planet without killing us. Even a micron per year would probably be deadly.

Do you really want to vent the heat off from the Earth's core? It would probably be best to try and keep it down there rather than risk the core cooling down.
Instead of venting while trying to cool down equipment, perhaps preventing it heating up would be better. Find some way to repel the heat. Probably something akin to a shield from Star Trek to deflect heat away and not something we have on hand at the moment.


The gold is unevenly mixed in with the other elements in the liquid core. Mining it will involve separating the gold atoms from the other atoms. It takes energy to sort one metal out from the others even if you start with molten metal. Thermodynamics tells us there is no such thing as a free lunch, and that any inefficiency in the process will come out as waste heat.

Our mythical mining machine will have to process many tonnes of core for each gram of gold. The core is pretty hot now, but it will get hotter as we extract the gold, unless we can put that heat somewhere else.

I have forgotten why we are trying to coat the earth with a layer of gold, but "what-if" thinking doesn't require that we even have a reason. For a "what-if", all that is important is to figure out what will happen assuming that physics and chemistry always follows the same rules.

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Soupspoon
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Re: 1944: "The End of the Rainbow"

Postby Soupspoon » Thu Jan 25, 2018 12:25 am UTC

We must first have covered the entire Earth with lilies, before we then gild it.


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