Could a terrestrial planet have water for a core?
Clash Royale CLAN TAG#URR8PPP
$begingroup$
There’s a planet called eaglypt whose surface is 100% barren desert. However, there is a twist: the planet’s core consists of liquid water, and there are a few places where this water seeps through the cracks and reaches the surface, where it creates fertile oases where civilizations can spring up, using the oases for irrigation. Is this realistic for a planet to exist like this or would it take serious artistic license for it to exist?
reality-check planets water deserts
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
$endgroup$
add a comment |
$begingroup$
There’s a planet called eaglypt whose surface is 100% barren desert. However, there is a twist: the planet’s core consists of liquid water, and there are a few places where this water seeps through the cracks and reaches the surface, where it creates fertile oases where civilizations can spring up, using the oases for irrigation. Is this realistic for a planet to exist like this or would it take serious artistic license for it to exist?
reality-check planets water deserts
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
$endgroup$
1
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21
add a comment |
$begingroup$
There’s a planet called eaglypt whose surface is 100% barren desert. However, there is a twist: the planet’s core consists of liquid water, and there are a few places where this water seeps through the cracks and reaches the surface, where it creates fertile oases where civilizations can spring up, using the oases for irrigation. Is this realistic for a planet to exist like this or would it take serious artistic license for it to exist?
reality-check planets water deserts
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
$endgroup$
There’s a planet called eaglypt whose surface is 100% barren desert. However, there is a twist: the planet’s core consists of liquid water, and there are a few places where this water seeps through the cracks and reaches the surface, where it creates fertile oases where civilizations can spring up, using the oases for irrigation. Is this realistic for a planet to exist like this or would it take serious artistic license for it to exist?
reality-check planets water deserts
reality-check planets water deserts
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
edited Jan 20 at 20:40
L.Dutch♦
83.5k28200412
83.5k28200412
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
asked Jan 20 at 20:38
The Weasel SagasThe Weasel Sagas
1,212121
1,212121
1
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21
add a comment |
1
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21
1
1
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21
add a comment |
4 Answers
4
active
oldest
votes
$begingroup$
Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great Artesian Basin, and the Nubian Sandstone Aquifer System.
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
$endgroup$
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
add a comment |
$begingroup$
For water to be at the core of the planet, it must mean that there are no other elements or components which are denser than water.
Now, water is pretty dense, but nowhere dense as most of the metals or oxides.
It can happen that only light elements are collected by gravity, but such a planet could not host life as we know it: no magnetic field to shield stellar wind, just to cite one big difference.
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
$endgroup$
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
add a comment |
$begingroup$
Yes. Water for a core, mantle and crust.
https://en.wikipedia.org/wiki/Desert
Polar deserts are a particular class of cold desert. The air is very
cold and carries little moisture so little precipitation occurs and
what does fall, usually snow, is carried along in the often strong
wind and may form blizzards, drifts and dunes similar to those caused
by dust and sand in other desert regions.
Your water world is dry on top because it is cold. Below the packed snow is ice, and more ice, and very eventually you will get down to liquid water. From OP
there are a few places where this water seeps through the cracks and
reaches the surface, where it creates fertile oases where
civilizations can spring up....
These hydrothermal springs come up thru cracks in the ice and sometimes can form pools of liquid water - very, very deep pools.
As regards a magnetosphere - I can think of no reason a water world should not have a magnetosphere. Salt water is a fine conductor of electricity and just as the moving metal of our world generates a magnetosphere to shield us from the solar wind, so too the salt water of your world's interior.
As regards those deep pools - it is a cold, dry, hardscrabble desert topside. Not so underneath. Fueled by the deep heat of the core, the life of the subsurface water world is rich and varied, and the fishing can be very good once you can get through. But if you hook something that does not put up a fight, cut your line fast and get everyone clear of the edge. Whatever it is might be coming up to have a look.
answered Jan 21 at 1:39
WillkWillk
107k26201447
$endgroup$
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
add a comment |
$begingroup$
It would take serious artistic license to exist, but...
I do not believe a planet could naturally evolve into this state. The problem isn't actually pressure. People assume that the further down you go, the more pressure there is. It's true to an extent, but the closer to the center you get the less you experience gravity (zero gravity at the center!). Pressure is something that makes sense when you're talking about the crust or rigid mantle. But if it applied to the liquid core, every crack in the mantle would result in massive eruptions — but they don't.
On the other hand, what you do get is heat. We don't really have proof of what's at the center of our planet, but a century of science has given us some really good guesses. We guess that there's a solid core. It's spinning at a different speed compared to the crust. Everything in the middle is subject to tremendous friction. Result = super heated rock. We think.
From the perspective of "solid stuff slowly combines via gravity over bazillions of years until some fool stamps his feet and says, 'let's call it a planet,'" this model works very well — but it doesn't explain where water comes from and that's actually been something scientists have pondered for a long time.
So, let's pretend that your world started as a honking lot of water orbiting a newly forming star and it starts to gather via gravity...
Why not? It's your world. From this perspective your world has a very, very low average density. There may still be a solid core of stuff (almost everything sinks through water, which is a better than average argument against this, unless there's a honking lot of water) but the middle isn't molten rock, it's super heated water.
And when the crust breaks, what you get is steam.
The crust is similar to a Roman arch — it's all spun out such that the bedrock is very, very flat and uniform. There would be no mountains — no plate tectonics to speak of — hot water, unlike magma, doesn't have the mass to push the surface around, which means earthquakes are caused by the heating/cooling cycle of the sun and occur most often at what we would call the tropics of cancer and capricorn (latitudes of highest thermal gradient between the poles and the equator).
This has the potential of meaning a lot of aquifers, but I'm having trouble keeping the land a desert. Water + sunlight = life. It would have to be a closer-to-the-sun planet such that the heat would burn off the water and the life. The consequence (thanks to the humidity) would be a lot of clouds, storms, and the night-side would get cold.
At least that's what I think.
answered Jan 21 at 1:02
JBHJBH
44.1k694210
$endgroup$
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
|
show 3 more comments
Your Answer
StackExchange.ifUsing("editor", function ()
return StackExchange.using("mathjaxEditing", function ()
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
);
);
, "mathjax-editing");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "579"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fworldbuilding.stackexchange.com%2fquestions%2f137186%2fcould-a-terrestrial-planet-have-water-for-a-core%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great Artesian Basin, and the Nubian Sandstone Aquifer System.
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
$endgroup$
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
add a comment |
$begingroup$
Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great Artesian Basin, and the Nubian Sandstone Aquifer System.
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
$endgroup$
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
add a comment |
$begingroup$
Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great Artesian Basin, and the Nubian Sandstone Aquifer System.
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
$endgroup$
Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great Artesian Basin, and the Nubian Sandstone Aquifer System.
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
answered Jan 20 at 20:42
Arkenstein XIIArkenstein XII
2,829730
2,829730
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
add a comment |
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
2
2
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
What happens to water at the pressure of a terrestrial planets core? For water I would think fluid would be the most compact phase.
$endgroup$
– Willk
Jan 21 at 2:58
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
@Willk It's a balance between temperature and pressure really, but for water, the most thermodynamically favourable phases at high pressures are various forms of exotic ice. en.wikipedia.org/wiki/Ice_VII
$endgroup$
– Arkenstein XII
Jan 21 at 3:07
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
$begingroup$
You might also note that there are quite possibly aquifers on Mars, too, as evidenced by the linear streaks on some crater walls.
$endgroup$
– jamesqf
Jan 21 at 4:18
1
1
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
$begingroup$
@Willk, the pressure at the Earth's core is around 350 GPa. At that pressure, the only possible phases are ice X, supercritical fluid (above 647 K), and possibly vapor (at a temperature of "absurdly hot"). The pressure's too high for liquid water.
$endgroup$
– Mark
Jan 21 at 5:25
add a comment |
$begingroup$
For water to be at the core of the planet, it must mean that there are no other elements or components which are denser than water.
Now, water is pretty dense, but nowhere dense as most of the metals or oxides.
It can happen that only light elements are collected by gravity, but such a planet could not host life as we know it: no magnetic field to shield stellar wind, just to cite one big difference.
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
$endgroup$
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
add a comment |
$begingroup$
For water to be at the core of the planet, it must mean that there are no other elements or components which are denser than water.
Now, water is pretty dense, but nowhere dense as most of the metals or oxides.
It can happen that only light elements are collected by gravity, but such a planet could not host life as we know it: no magnetic field to shield stellar wind, just to cite one big difference.
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
$endgroup$
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
add a comment |
$begingroup$
For water to be at the core of the planet, it must mean that there are no other elements or components which are denser than water.
Now, water is pretty dense, but nowhere dense as most of the metals or oxides.
It can happen that only light elements are collected by gravity, but such a planet could not host life as we know it: no magnetic field to shield stellar wind, just to cite one big difference.
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
$endgroup$
For water to be at the core of the planet, it must mean that there are no other elements or components which are denser than water.
Now, water is pretty dense, but nowhere dense as most of the metals or oxides.
It can happen that only light elements are collected by gravity, but such a planet could not host life as we know it: no magnetic field to shield stellar wind, just to cite one big difference.
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
answered Jan 20 at 20:43
L.Dutch♦L.Dutch
83.5k28200412
83.5k28200412
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
add a comment |
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
$begingroup$
Couldn't elements be present if they were bound in low-density compounds? Not sure if that would admit a magnetic field or not.
$endgroup$
– R..
Jan 21 at 1:10
1
1
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
$begingroup$
@R.., the presence of water means that most of the elements present will be in the form of oxides, and these tend to be a good bit denser than water. (Think about it: most rocks are oxides, and very few rocks float.)
$endgroup$
– Mark
Jan 21 at 5:18
add a comment |
$begingroup$
Yes. Water for a core, mantle and crust.
https://en.wikipedia.org/wiki/Desert
Polar deserts are a particular class of cold desert. The air is very
cold and carries little moisture so little precipitation occurs and
what does fall, usually snow, is carried along in the often strong
wind and may form blizzards, drifts and dunes similar to those caused
by dust and sand in other desert regions.
Your water world is dry on top because it is cold. Below the packed snow is ice, and more ice, and very eventually you will get down to liquid water. From OP
there are a few places where this water seeps through the cracks and
reaches the surface, where it creates fertile oases where
civilizations can spring up....
These hydrothermal springs come up thru cracks in the ice and sometimes can form pools of liquid water - very, very deep pools.
As regards a magnetosphere - I can think of no reason a water world should not have a magnetosphere. Salt water is a fine conductor of electricity and just as the moving metal of our world generates a magnetosphere to shield us from the solar wind, so too the salt water of your world's interior.
As regards those deep pools - it is a cold, dry, hardscrabble desert topside. Not so underneath. Fueled by the deep heat of the core, the life of the subsurface water world is rich and varied, and the fishing can be very good once you can get through. But if you hook something that does not put up a fight, cut your line fast and get everyone clear of the edge. Whatever it is might be coming up to have a look.
answered Jan 21 at 1:39
WillkWillk
107k26201447
$endgroup$
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
add a comment |
$begingroup$
Yes. Water for a core, mantle and crust.
https://en.wikipedia.org/wiki/Desert
Polar deserts are a particular class of cold desert. The air is very
cold and carries little moisture so little precipitation occurs and
what does fall, usually snow, is carried along in the often strong
wind and may form blizzards, drifts and dunes similar to those caused
by dust and sand in other desert regions.
Your water world is dry on top because it is cold. Below the packed snow is ice, and more ice, and very eventually you will get down to liquid water. From OP
there are a few places where this water seeps through the cracks and
reaches the surface, where it creates fertile oases where
civilizations can spring up....
These hydrothermal springs come up thru cracks in the ice and sometimes can form pools of liquid water - very, very deep pools.
As regards a magnetosphere - I can think of no reason a water world should not have a magnetosphere. Salt water is a fine conductor of electricity and just as the moving metal of our world generates a magnetosphere to shield us from the solar wind, so too the salt water of your world's interior.
As regards those deep pools - it is a cold, dry, hardscrabble desert topside. Not so underneath. Fueled by the deep heat of the core, the life of the subsurface water world is rich and varied, and the fishing can be very good once you can get through. But if you hook something that does not put up a fight, cut your line fast and get everyone clear of the edge. Whatever it is might be coming up to have a look.
answered Jan 21 at 1:39
WillkWillk
107k26201447
$endgroup$
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
add a comment |
$begingroup$
Yes. Water for a core, mantle and crust.
https://en.wikipedia.org/wiki/Desert
Polar deserts are a particular class of cold desert. The air is very
cold and carries little moisture so little precipitation occurs and
what does fall, usually snow, is carried along in the often strong
wind and may form blizzards, drifts and dunes similar to those caused
by dust and sand in other desert regions.
Your water world is dry on top because it is cold. Below the packed snow is ice, and more ice, and very eventually you will get down to liquid water. From OP
there are a few places where this water seeps through the cracks and
reaches the surface, where it creates fertile oases where
civilizations can spring up....
These hydrothermal springs come up thru cracks in the ice and sometimes can form pools of liquid water - very, very deep pools.
As regards a magnetosphere - I can think of no reason a water world should not have a magnetosphere. Salt water is a fine conductor of electricity and just as the moving metal of our world generates a magnetosphere to shield us from the solar wind, so too the salt water of your world's interior.
As regards those deep pools - it is a cold, dry, hardscrabble desert topside. Not so underneath. Fueled by the deep heat of the core, the life of the subsurface water world is rich and varied, and the fishing can be very good once you can get through. But if you hook something that does not put up a fight, cut your line fast and get everyone clear of the edge. Whatever it is might be coming up to have a look.
answered Jan 21 at 1:39
WillkWillk
107k26201447
$endgroup$
Yes. Water for a core, mantle and crust.
https://en.wikipedia.org/wiki/Desert
Polar deserts are a particular class of cold desert. The air is very
cold and carries little moisture so little precipitation occurs and
what does fall, usually snow, is carried along in the often strong
wind and may form blizzards, drifts and dunes similar to those caused
by dust and sand in other desert regions.
Your water world is dry on top because it is cold. Below the packed snow is ice, and more ice, and very eventually you will get down to liquid water. From OP
there are a few places where this water seeps through the cracks and
reaches the surface, where it creates fertile oases where
civilizations can spring up....
These hydrothermal springs come up thru cracks in the ice and sometimes can form pools of liquid water - very, very deep pools.
As regards a magnetosphere - I can think of no reason a water world should not have a magnetosphere. Salt water is a fine conductor of electricity and just as the moving metal of our world generates a magnetosphere to shield us from the solar wind, so too the salt water of your world's interior.
As regards those deep pools - it is a cold, dry, hardscrabble desert topside. Not so underneath. Fueled by the deep heat of the core, the life of the subsurface water world is rich and varied, and the fishing can be very good once you can get through. But if you hook something that does not put up a fight, cut your line fast and get everyone clear of the edge. Whatever it is might be coming up to have a look.
answered Jan 21 at 1:39
WillkWillk
107k26201447
answered Jan 21 at 1:39
WillkWillk
107k26201447
answered Jan 21 at 1:39
WillkWillk
107k26201447
answered Jan 21 at 1:39
WillkWillk
107k26201447
107k26201447
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
add a comment |
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
1
1
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
$begingroup$
We've had a few questions about water worlds on this site (eg. worldbuilding.stackexchange.com/questions/54134/…, worldbuilding.stackexchange.com/questions/106732/…). Short version: once you get larger than about the size of Mercury, you're going to get an ice core, not a liquid core.
$endgroup$
– Mark
Jan 21 at 5:29
add a comment |
$begingroup$
It would take serious artistic license to exist, but...
I do not believe a planet could naturally evolve into this state. The problem isn't actually pressure. People assume that the further down you go, the more pressure there is. It's true to an extent, but the closer to the center you get the less you experience gravity (zero gravity at the center!). Pressure is something that makes sense when you're talking about the crust or rigid mantle. But if it applied to the liquid core, every crack in the mantle would result in massive eruptions — but they don't.
On the other hand, what you do get is heat. We don't really have proof of what's at the center of our planet, but a century of science has given us some really good guesses. We guess that there's a solid core. It's spinning at a different speed compared to the crust. Everything in the middle is subject to tremendous friction. Result = super heated rock. We think.
From the perspective of "solid stuff slowly combines via gravity over bazillions of years until some fool stamps his feet and says, 'let's call it a planet,'" this model works very well — but it doesn't explain where water comes from and that's actually been something scientists have pondered for a long time.
So, let's pretend that your world started as a honking lot of water orbiting a newly forming star and it starts to gather via gravity...
Why not? It's your world. From this perspective your world has a very, very low average density. There may still be a solid core of stuff (almost everything sinks through water, which is a better than average argument against this, unless there's a honking lot of water) but the middle isn't molten rock, it's super heated water.
And when the crust breaks, what you get is steam.
The crust is similar to a Roman arch — it's all spun out such that the bedrock is very, very flat and uniform. There would be no mountains — no plate tectonics to speak of — hot water, unlike magma, doesn't have the mass to push the surface around, which means earthquakes are caused by the heating/cooling cycle of the sun and occur most often at what we would call the tropics of cancer and capricorn (latitudes of highest thermal gradient between the poles and the equator).
This has the potential of meaning a lot of aquifers, but I'm having trouble keeping the land a desert. Water + sunlight = life. It would have to be a closer-to-the-sun planet such that the heat would burn off the water and the life. The consequence (thanks to the humidity) would be a lot of clouds, storms, and the night-side would get cold.
At least that's what I think.
answered Jan 21 at 1:02
JBHJBH
44.1k694210
$endgroup$
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
|
show 3 more comments
$begingroup$
It would take serious artistic license to exist, but...
I do not believe a planet could naturally evolve into this state. The problem isn't actually pressure. People assume that the further down you go, the more pressure there is. It's true to an extent, but the closer to the center you get the less you experience gravity (zero gravity at the center!). Pressure is something that makes sense when you're talking about the crust or rigid mantle. But if it applied to the liquid core, every crack in the mantle would result in massive eruptions — but they don't.
On the other hand, what you do get is heat. We don't really have proof of what's at the center of our planet, but a century of science has given us some really good guesses. We guess that there's a solid core. It's spinning at a different speed compared to the crust. Everything in the middle is subject to tremendous friction. Result = super heated rock. We think.
From the perspective of "solid stuff slowly combines via gravity over bazillions of years until some fool stamps his feet and says, 'let's call it a planet,'" this model works very well — but it doesn't explain where water comes from and that's actually been something scientists have pondered for a long time.
So, let's pretend that your world started as a honking lot of water orbiting a newly forming star and it starts to gather via gravity...
Why not? It's your world. From this perspective your world has a very, very low average density. There may still be a solid core of stuff (almost everything sinks through water, which is a better than average argument against this, unless there's a honking lot of water) but the middle isn't molten rock, it's super heated water.
And when the crust breaks, what you get is steam.
The crust is similar to a Roman arch — it's all spun out such that the bedrock is very, very flat and uniform. There would be no mountains — no plate tectonics to speak of — hot water, unlike magma, doesn't have the mass to push the surface around, which means earthquakes are caused by the heating/cooling cycle of the sun and occur most often at what we would call the tropics of cancer and capricorn (latitudes of highest thermal gradient between the poles and the equator).
This has the potential of meaning a lot of aquifers, but I'm having trouble keeping the land a desert. Water + sunlight = life. It would have to be a closer-to-the-sun planet such that the heat would burn off the water and the life. The consequence (thanks to the humidity) would be a lot of clouds, storms, and the night-side would get cold.
At least that's what I think.
answered Jan 21 at 1:02
JBHJBH
44.1k694210
$endgroup$
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
|
show 3 more comments
$begingroup$
It would take serious artistic license to exist, but...
I do not believe a planet could naturally evolve into this state. The problem isn't actually pressure. People assume that the further down you go, the more pressure there is. It's true to an extent, but the closer to the center you get the less you experience gravity (zero gravity at the center!). Pressure is something that makes sense when you're talking about the crust or rigid mantle. But if it applied to the liquid core, every crack in the mantle would result in massive eruptions — but they don't.
On the other hand, what you do get is heat. We don't really have proof of what's at the center of our planet, but a century of science has given us some really good guesses. We guess that there's a solid core. It's spinning at a different speed compared to the crust. Everything in the middle is subject to tremendous friction. Result = super heated rock. We think.
From the perspective of "solid stuff slowly combines via gravity over bazillions of years until some fool stamps his feet and says, 'let's call it a planet,'" this model works very well — but it doesn't explain where water comes from and that's actually been something scientists have pondered for a long time.
So, let's pretend that your world started as a honking lot of water orbiting a newly forming star and it starts to gather via gravity...
Why not? It's your world. From this perspective your world has a very, very low average density. There may still be a solid core of stuff (almost everything sinks through water, which is a better than average argument against this, unless there's a honking lot of water) but the middle isn't molten rock, it's super heated water.
And when the crust breaks, what you get is steam.
The crust is similar to a Roman arch — it's all spun out such that the bedrock is very, very flat and uniform. There would be no mountains — no plate tectonics to speak of — hot water, unlike magma, doesn't have the mass to push the surface around, which means earthquakes are caused by the heating/cooling cycle of the sun and occur most often at what we would call the tropics of cancer and capricorn (latitudes of highest thermal gradient between the poles and the equator).
This has the potential of meaning a lot of aquifers, but I'm having trouble keeping the land a desert. Water + sunlight = life. It would have to be a closer-to-the-sun planet such that the heat would burn off the water and the life. The consequence (thanks to the humidity) would be a lot of clouds, storms, and the night-side would get cold.
At least that's what I think.
answered Jan 21 at 1:02
JBHJBH
44.1k694210
$endgroup$
It would take serious artistic license to exist, but...
I do not believe a planet could naturally evolve into this state. The problem isn't actually pressure. People assume that the further down you go, the more pressure there is. It's true to an extent, but the closer to the center you get the less you experience gravity (zero gravity at the center!). Pressure is something that makes sense when you're talking about the crust or rigid mantle. But if it applied to the liquid core, every crack in the mantle would result in massive eruptions — but they don't.
On the other hand, what you do get is heat. We don't really have proof of what's at the center of our planet, but a century of science has given us some really good guesses. We guess that there's a solid core. It's spinning at a different speed compared to the crust. Everything in the middle is subject to tremendous friction. Result = super heated rock. We think.
From the perspective of "solid stuff slowly combines via gravity over bazillions of years until some fool stamps his feet and says, 'let's call it a planet,'" this model works very well — but it doesn't explain where water comes from and that's actually been something scientists have pondered for a long time.
So, let's pretend that your world started as a honking lot of water orbiting a newly forming star and it starts to gather via gravity...
Why not? It's your world. From this perspective your world has a very, very low average density. There may still be a solid core of stuff (almost everything sinks through water, which is a better than average argument against this, unless there's a honking lot of water) but the middle isn't molten rock, it's super heated water.
And when the crust breaks, what you get is steam.
The crust is similar to a Roman arch — it's all spun out such that the bedrock is very, very flat and uniform. There would be no mountains — no plate tectonics to speak of — hot water, unlike magma, doesn't have the mass to push the surface around, which means earthquakes are caused by the heating/cooling cycle of the sun and occur most often at what we would call the tropics of cancer and capricorn (latitudes of highest thermal gradient between the poles and the equator).
This has the potential of meaning a lot of aquifers, but I'm having trouble keeping the land a desert. Water + sunlight = life. It would have to be a closer-to-the-sun planet such that the heat would burn off the water and the life. The consequence (thanks to the humidity) would be a lot of clouds, storms, and the night-side would get cold.
At least that's what I think.
answered Jan 21 at 1:02
JBHJBH
44.1k694210
answered Jan 21 at 1:02
JBHJBH
44.1k694210
answered Jan 21 at 1:02
JBHJBH
44.1k694210
answered Jan 21 at 1:02
JBHJBH
44.1k694210
44.1k694210
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
|
show 3 more comments
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
1
1
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
$begingroup$
Sorry, mate... this is not a very good answer. The interior of the Earth is under immense pressure. Whether or not one "experiences gravity" is utterly meaningless to the question of pressure. Pressure is the result of the weight of thousands of kilometres of rock bearing down from above. At the boundary between the outer and inner cores, pressure is roughly 360 gigapascals. Furthermore, friction is not the cause of internal heating. At all. Rather, it is the result of the radioactive decay of heavy elements in the core.
$endgroup$
– Arkenstein XII
Jan 21 at 2:11
2
2
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
$begingroup$
The only point in the Earth that experiences zero gravity is the centre of gravity. Everywhere else, gravity is being exerted. As to where I got that figure, we should start with the fact that I am a qualified geoscientist. If that is insufficient, I will point out that Wikipedia agrees with me, and cites the following: David. R. Lide, ed. (2006–2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13
$endgroup$
– Arkenstein XII
Jan 21 at 2:25
1
1
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
$begingroup$
A link to a Physics.SE question that covers this: physics.stackexchange.com/questions/184032/…
$endgroup$
– Arkenstein XII
Jan 21 at 2:31
2
2
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
$begingroup$
Engineering PhD here. Arkenstein is correct. If the pressure at the core was lower than the pressure in upper layers, then that would create a net downward force which would compress the core until it had at least as much pressure as the upper layers. Roughly speaking, gravity tells you how fast pressure is increasing with depth - so as you approach the centre, pressure will plateau, but not drop.
$endgroup$
– Geoffrey Brent
Jan 21 at 3:04
2
2
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
$begingroup$
You are failing to grasp the physics of the matter. While at the centre of mass, the net gravity experienced is zero, that does not nullify the fact that the 6370km of rock and metal on all sides is absolutely experiencing gravity and is therefore exerting pressure in the direction of that centre of mass. Further links for your perusal: hypertextbook.com/facts/1999/PavelKhazron.shtml researchgate.net/figure/…
$endgroup$
– Arkenstein XII
Jan 21 at 3:04
|
show 3 more comments
Thanks for contributing an answer to Worldbuilding Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fworldbuilding.stackexchange.com%2fquestions%2f137186%2fcould-a-terrestrial-planet-have-water-for-a-core%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
1
$begingroup$
Putting aside the impossibility of a water core and a surface of rock & sand, how does life evolve without large areas of liquid water? Your best bet would be a Mars-like planet, which started out with significant water but lost most of it.
$endgroup$
– jamesqf
Jan 21 at 4:21