Would a high gravity rocky planet be guaranteed to have an atmosphere? The Next CEO of Stack OverflowWould oxygen pool in sink holes if the upper atmosphere was helium, hydrogen and methane?What are the requirements for an atmosphere retaining moon with a stable orbit arround an earth like planet with non-destructive tidal forces?What would happen to a high-pressure creature in a low-pressure atmosphere? (3atm)What would happen to a high-pressure creature in a low-pressure atmosphere (50atm)?How fast would a planet have to be spinning for the centrifugal/centripetal force to cancel out the force of gravity near the equator?Could a planet larger than earth with half the gravity have a denser atmosphere?What are the climatological effects to the surface of a planet where the atmosphere gives way to vaccum? (diagram included)5km artificial planet, with same gravity as on EarthCould a habitable planet with lower gravity have a thick atmosphere?How can this habitable planet have a moon with a naturally occurring atmosphere?
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Would a high gravity rocky planet be guaranteed to have an atmosphere?
The Next CEO of Stack OverflowWould oxygen pool in sink holes if the upper atmosphere was helium, hydrogen and methane?What are the requirements for an atmosphere retaining moon with a stable orbit arround an earth like planet with non-destructive tidal forces?What would happen to a high-pressure creature in a low-pressure atmosphere? (3atm)What would happen to a high-pressure creature in a low-pressure atmosphere (50atm)?How fast would a planet have to be spinning for the centrifugal/centripetal force to cancel out the force of gravity near the equator?Could a planet larger than earth with half the gravity have a denser atmosphere?What are the climatological effects to the surface of a planet where the atmosphere gives way to vaccum? (diagram included)5km artificial planet, with same gravity as on EarthCould a habitable planet with lower gravity have a thick atmosphere?How can this habitable planet have a moon with a naturally occurring atmosphere?
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I want to create a planet with a deep gravity well, say about 12G at the surface. At first I wanted the planet to have either no atmosphere or a very thin one. But I want this to be as close to realistic as possible. So, would a planet be guaranteed to have a thick atmosphere with a gravity well that deep?
reality-check planets gravity atmosphere
New contributor
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add a comment |
$begingroup$
I want to create a planet with a deep gravity well, say about 12G at the surface. At first I wanted the planet to have either no atmosphere or a very thin one. But I want this to be as close to realistic as possible. So, would a planet be guaranteed to have a thick atmosphere with a gravity well that deep?
reality-check planets gravity atmosphere
New contributor
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Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
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– Cyn
2 days ago
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Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
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– user2284570
2 days ago
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Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday
add a comment |
$begingroup$
I want to create a planet with a deep gravity well, say about 12G at the surface. At first I wanted the planet to have either no atmosphere or a very thin one. But I want this to be as close to realistic as possible. So, would a planet be guaranteed to have a thick atmosphere with a gravity well that deep?
reality-check planets gravity atmosphere
New contributor
$endgroup$
I want to create a planet with a deep gravity well, say about 12G at the surface. At first I wanted the planet to have either no atmosphere or a very thin one. But I want this to be as close to realistic as possible. So, would a planet be guaranteed to have a thick atmosphere with a gravity well that deep?
reality-check planets gravity atmosphere
reality-check planets gravity atmosphere
New contributor
New contributor
edited 2 days ago
Sean Kindle
New contributor
asked 2 days ago
Sean KindleSean Kindle
687
687
New contributor
New contributor
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Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
$endgroup$
– Cyn
2 days ago
$begingroup$
Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
$endgroup$
– user2284570
2 days ago
$begingroup$
Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday
add a comment |
$begingroup$
Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
$endgroup$
– Cyn
2 days ago
$begingroup$
Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
$endgroup$
– user2284570
2 days ago
$begingroup$
Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday
$begingroup$
Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
$endgroup$
– Cyn
2 days ago
$begingroup$
Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
$endgroup$
– Cyn
2 days ago
$begingroup$
Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
$endgroup$
– user2284570
2 days ago
$begingroup$
Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
$endgroup$
– user2284570
2 days ago
$begingroup$
Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday
$begingroup$
Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday
add a comment |
4 Answers
4
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oldest
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You ask a tricky question because the case you describe -- a rocky planet with 12G surface gravity -- is extremely unlikely. If the planet is defined as being rocky, then it's made of normal matter (not neutron star or white dwarf stuff) and to have 12G surface gravity, it would have to be quite large.
For a constant density sphere, the surface gravity increases proportional to the sphere's radius, so to have 12G surface gravity it would have to be around 12 times the diameter of the Earth. (The surface gravity is proportional to the planet's mass which is proportional to the cube of the radius. And surface gravity is also inversely proportional to the square of the radius (because the surface in further from the center and the inverse square law). The net effect is a proportionality to radius.)
Even rocks compress, so 12x is somewhat of an overestimate. Say it's "only" 10x the diameter of the Earth. It's still very difficult to see how a rocky planet 10x the diameter of Earth (meaning a mass of 1000 Earths -- greater than Jupiter!) could avoid picking up a huge atmosphere of gasses and being a typical Super Jupiter or even a small star.
About the only way I can think of is if the star it circles went through a very high luminosity phase and stripped away nearly all the atmosphere. (Since hot Jupiters are common, it seems unlikely that a planet that massive even one forming near a star could avoid a big atmosphere. It pretty much has to have had its atmosphere stripped later.) Not so clear that life would survive on it then.
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add a comment |
$begingroup$
Likely, but not guaranteed. Consider a large rocky planet very close to its star. There is certainly a possibility that the atmosphere would be boiled off / stripped away by the star.
This would be the case if, for instance, Mercury were orders of magnitude more massive. If your large rocky planet is close enough to its star to make this case true, you will have to deal with strange conditions for your character. One example is the planet is likely to be tidally locked, with an extremely hot side always facing the star and an extremely cold side always facing away from the star.
Whether humans have actually discovered a planet that meets these criteria is probably up for debate. Most inquiries into exoplanet atmospheres make the assumption that the existence or lack of atmosphere is unknown until the presence of an atmosphere is proven definitively.
$endgroup$
add a comment |
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I think I see a scenario that could produce your world. Note that this is cataclysmic on an interstellar scale--life on nearby stars would have been eradicated.
We need a system that starts out with three stars, two of which are a close binary and each star exceeds (but not by too much) 8 solar masses. The third star is more distant and somewhat smaller.
The two big stars burn through their fuel and supernova, leaving behind neutron stars. The third is abused by these detonations but survives. The neutron stars are like their parents--a close binary. In time they spiral in and go splat--but enough mass is thrown off in the process to make your high-G world, from which a planet is born. (Note that I'm not sure it's possible for it to end up in a planet. The process is extremely energetic, it might be ejected too fast.)
Now you have a neutron star or black hole, a super-planet and an ordinary star. Now it's time for our third star to die--this time more peacefully, to a white dwarf.
This collection of debris encounters another star which ends up captured, the super-planet ending up in the life zone of the new star. The white dwarf sucks in matter from this fourth star, eventually you get a nova. This scours the atmosphere off the super-planet.
You're now left with a super-planet with no atmosphere. It's going to be an incredibly dense world as much of the stuff thrown off from the neutron star impact is from the lower part of the periodic table.
While you didn't ask for it this is going to be an immensely valuable source of heavy metals. (This is assuming it's worthwhile to ship such stuff. If you have a brute-force stardrive it probably isn't.)
Note that this is a very dangerous star system to be in, the white dwarf will periodically nova (although a sufficiently advanced science should be able to predict the detonations) and if it sucks down enough matter it will be even worse when it collapses down to a neutron star. You also have the jets from the other neutron star or black hole, although they could be aimed in a safe direction.
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Heavy metal world.
- 12G planet. You could ramp up the gravity by making the core more dense. Our planet has an iron / nickel core under the rocks, and those have atomic weights of 55 and 58. Uranium has an atomic weight of 238. So if you made the core out of uranium and other heavy friends your density is 5x that of earth. Those elements are rarer than iron but not crazy rare. Now your planet only needs to be 2.4x as big as earth to have your 12G. If you want your planet even smaller, you can invoke the stable superheavy elements from the undiscovered far reaches of the periodic table - the island of stability
There could be other cool things about the uranium planet. Maybe natural fission goes on deep inside, which would make for rocking volcanoes. Could you take advantage of this to get off planet? Hmm... Also, the atmosphere would have a lot of radon, which would give everyone very low voices among other things.
- My understanding of atmosphere is that you need a magnetosphere to keep it in, gravity notwithstanding. Otherwise the solar wind will strip it away. Mars lost its magnetosphere and then lost its atmosphere because of that. No reason to think that the heavy planet would not have a magnetosphere.
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2
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Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
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– Arkenstein XII
2 days ago
2
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Only if it had significant U-235, Uranium-238 is really no danger.
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– user2617804
yesterday
1
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While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
add a comment |
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4 Answers
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4 Answers
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$begingroup$
You ask a tricky question because the case you describe -- a rocky planet with 12G surface gravity -- is extremely unlikely. If the planet is defined as being rocky, then it's made of normal matter (not neutron star or white dwarf stuff) and to have 12G surface gravity, it would have to be quite large.
For a constant density sphere, the surface gravity increases proportional to the sphere's radius, so to have 12G surface gravity it would have to be around 12 times the diameter of the Earth. (The surface gravity is proportional to the planet's mass which is proportional to the cube of the radius. And surface gravity is also inversely proportional to the square of the radius (because the surface in further from the center and the inverse square law). The net effect is a proportionality to radius.)
Even rocks compress, so 12x is somewhat of an overestimate. Say it's "only" 10x the diameter of the Earth. It's still very difficult to see how a rocky planet 10x the diameter of Earth (meaning a mass of 1000 Earths -- greater than Jupiter!) could avoid picking up a huge atmosphere of gasses and being a typical Super Jupiter or even a small star.
About the only way I can think of is if the star it circles went through a very high luminosity phase and stripped away nearly all the atmosphere. (Since hot Jupiters are common, it seems unlikely that a planet that massive even one forming near a star could avoid a big atmosphere. It pretty much has to have had its atmosphere stripped later.) Not so clear that life would survive on it then.
$endgroup$
add a comment |
$begingroup$
You ask a tricky question because the case you describe -- a rocky planet with 12G surface gravity -- is extremely unlikely. If the planet is defined as being rocky, then it's made of normal matter (not neutron star or white dwarf stuff) and to have 12G surface gravity, it would have to be quite large.
For a constant density sphere, the surface gravity increases proportional to the sphere's radius, so to have 12G surface gravity it would have to be around 12 times the diameter of the Earth. (The surface gravity is proportional to the planet's mass which is proportional to the cube of the radius. And surface gravity is also inversely proportional to the square of the radius (because the surface in further from the center and the inverse square law). The net effect is a proportionality to radius.)
Even rocks compress, so 12x is somewhat of an overestimate. Say it's "only" 10x the diameter of the Earth. It's still very difficult to see how a rocky planet 10x the diameter of Earth (meaning a mass of 1000 Earths -- greater than Jupiter!) could avoid picking up a huge atmosphere of gasses and being a typical Super Jupiter or even a small star.
About the only way I can think of is if the star it circles went through a very high luminosity phase and stripped away nearly all the atmosphere. (Since hot Jupiters are common, it seems unlikely that a planet that massive even one forming near a star could avoid a big atmosphere. It pretty much has to have had its atmosphere stripped later.) Not so clear that life would survive on it then.
$endgroup$
add a comment |
$begingroup$
You ask a tricky question because the case you describe -- a rocky planet with 12G surface gravity -- is extremely unlikely. If the planet is defined as being rocky, then it's made of normal matter (not neutron star or white dwarf stuff) and to have 12G surface gravity, it would have to be quite large.
For a constant density sphere, the surface gravity increases proportional to the sphere's radius, so to have 12G surface gravity it would have to be around 12 times the diameter of the Earth. (The surface gravity is proportional to the planet's mass which is proportional to the cube of the radius. And surface gravity is also inversely proportional to the square of the radius (because the surface in further from the center and the inverse square law). The net effect is a proportionality to radius.)
Even rocks compress, so 12x is somewhat of an overestimate. Say it's "only" 10x the diameter of the Earth. It's still very difficult to see how a rocky planet 10x the diameter of Earth (meaning a mass of 1000 Earths -- greater than Jupiter!) could avoid picking up a huge atmosphere of gasses and being a typical Super Jupiter or even a small star.
About the only way I can think of is if the star it circles went through a very high luminosity phase and stripped away nearly all the atmosphere. (Since hot Jupiters are common, it seems unlikely that a planet that massive even one forming near a star could avoid a big atmosphere. It pretty much has to have had its atmosphere stripped later.) Not so clear that life would survive on it then.
$endgroup$
You ask a tricky question because the case you describe -- a rocky planet with 12G surface gravity -- is extremely unlikely. If the planet is defined as being rocky, then it's made of normal matter (not neutron star or white dwarf stuff) and to have 12G surface gravity, it would have to be quite large.
For a constant density sphere, the surface gravity increases proportional to the sphere's radius, so to have 12G surface gravity it would have to be around 12 times the diameter of the Earth. (The surface gravity is proportional to the planet's mass which is proportional to the cube of the radius. And surface gravity is also inversely proportional to the square of the radius (because the surface in further from the center and the inverse square law). The net effect is a proportionality to radius.)
Even rocks compress, so 12x is somewhat of an overestimate. Say it's "only" 10x the diameter of the Earth. It's still very difficult to see how a rocky planet 10x the diameter of Earth (meaning a mass of 1000 Earths -- greater than Jupiter!) could avoid picking up a huge atmosphere of gasses and being a typical Super Jupiter or even a small star.
About the only way I can think of is if the star it circles went through a very high luminosity phase and stripped away nearly all the atmosphere. (Since hot Jupiters are common, it seems unlikely that a planet that massive even one forming near a star could avoid a big atmosphere. It pretty much has to have had its atmosphere stripped later.) Not so clear that life would survive on it then.
answered 2 days ago
Mark OlsonMark Olson
11.9k12849
11.9k12849
add a comment |
add a comment |
$begingroup$
Likely, but not guaranteed. Consider a large rocky planet very close to its star. There is certainly a possibility that the atmosphere would be boiled off / stripped away by the star.
This would be the case if, for instance, Mercury were orders of magnitude more massive. If your large rocky planet is close enough to its star to make this case true, you will have to deal with strange conditions for your character. One example is the planet is likely to be tidally locked, with an extremely hot side always facing the star and an extremely cold side always facing away from the star.
Whether humans have actually discovered a planet that meets these criteria is probably up for debate. Most inquiries into exoplanet atmospheres make the assumption that the existence or lack of atmosphere is unknown until the presence of an atmosphere is proven definitively.
$endgroup$
add a comment |
$begingroup$
Likely, but not guaranteed. Consider a large rocky planet very close to its star. There is certainly a possibility that the atmosphere would be boiled off / stripped away by the star.
This would be the case if, for instance, Mercury were orders of magnitude more massive. If your large rocky planet is close enough to its star to make this case true, you will have to deal with strange conditions for your character. One example is the planet is likely to be tidally locked, with an extremely hot side always facing the star and an extremely cold side always facing away from the star.
Whether humans have actually discovered a planet that meets these criteria is probably up for debate. Most inquiries into exoplanet atmospheres make the assumption that the existence or lack of atmosphere is unknown until the presence of an atmosphere is proven definitively.
$endgroup$
add a comment |
$begingroup$
Likely, but not guaranteed. Consider a large rocky planet very close to its star. There is certainly a possibility that the atmosphere would be boiled off / stripped away by the star.
This would be the case if, for instance, Mercury were orders of magnitude more massive. If your large rocky planet is close enough to its star to make this case true, you will have to deal with strange conditions for your character. One example is the planet is likely to be tidally locked, with an extremely hot side always facing the star and an extremely cold side always facing away from the star.
Whether humans have actually discovered a planet that meets these criteria is probably up for debate. Most inquiries into exoplanet atmospheres make the assumption that the existence or lack of atmosphere is unknown until the presence of an atmosphere is proven definitively.
$endgroup$
Likely, but not guaranteed. Consider a large rocky planet very close to its star. There is certainly a possibility that the atmosphere would be boiled off / stripped away by the star.
This would be the case if, for instance, Mercury were orders of magnitude more massive. If your large rocky planet is close enough to its star to make this case true, you will have to deal with strange conditions for your character. One example is the planet is likely to be tidally locked, with an extremely hot side always facing the star and an extremely cold side always facing away from the star.
Whether humans have actually discovered a planet that meets these criteria is probably up for debate. Most inquiries into exoplanet atmospheres make the assumption that the existence or lack of atmosphere is unknown until the presence of an atmosphere is proven definitively.
answered 2 days ago
benben
7767
7767
add a comment |
add a comment |
$begingroup$
I think I see a scenario that could produce your world. Note that this is cataclysmic on an interstellar scale--life on nearby stars would have been eradicated.
We need a system that starts out with three stars, two of which are a close binary and each star exceeds (but not by too much) 8 solar masses. The third star is more distant and somewhat smaller.
The two big stars burn through their fuel and supernova, leaving behind neutron stars. The third is abused by these detonations but survives. The neutron stars are like their parents--a close binary. In time they spiral in and go splat--but enough mass is thrown off in the process to make your high-G world, from which a planet is born. (Note that I'm not sure it's possible for it to end up in a planet. The process is extremely energetic, it might be ejected too fast.)
Now you have a neutron star or black hole, a super-planet and an ordinary star. Now it's time for our third star to die--this time more peacefully, to a white dwarf.
This collection of debris encounters another star which ends up captured, the super-planet ending up in the life zone of the new star. The white dwarf sucks in matter from this fourth star, eventually you get a nova. This scours the atmosphere off the super-planet.
You're now left with a super-planet with no atmosphere. It's going to be an incredibly dense world as much of the stuff thrown off from the neutron star impact is from the lower part of the periodic table.
While you didn't ask for it this is going to be an immensely valuable source of heavy metals. (This is assuming it's worthwhile to ship such stuff. If you have a brute-force stardrive it probably isn't.)
Note that this is a very dangerous star system to be in, the white dwarf will periodically nova (although a sufficiently advanced science should be able to predict the detonations) and if it sucks down enough matter it will be even worse when it collapses down to a neutron star. You also have the jets from the other neutron star or black hole, although they could be aimed in a safe direction.
$endgroup$
add a comment |
$begingroup$
I think I see a scenario that could produce your world. Note that this is cataclysmic on an interstellar scale--life on nearby stars would have been eradicated.
We need a system that starts out with three stars, two of which are a close binary and each star exceeds (but not by too much) 8 solar masses. The third star is more distant and somewhat smaller.
The two big stars burn through their fuel and supernova, leaving behind neutron stars. The third is abused by these detonations but survives. The neutron stars are like their parents--a close binary. In time they spiral in and go splat--but enough mass is thrown off in the process to make your high-G world, from which a planet is born. (Note that I'm not sure it's possible for it to end up in a planet. The process is extremely energetic, it might be ejected too fast.)
Now you have a neutron star or black hole, a super-planet and an ordinary star. Now it's time for our third star to die--this time more peacefully, to a white dwarf.
This collection of debris encounters another star which ends up captured, the super-planet ending up in the life zone of the new star. The white dwarf sucks in matter from this fourth star, eventually you get a nova. This scours the atmosphere off the super-planet.
You're now left with a super-planet with no atmosphere. It's going to be an incredibly dense world as much of the stuff thrown off from the neutron star impact is from the lower part of the periodic table.
While you didn't ask for it this is going to be an immensely valuable source of heavy metals. (This is assuming it's worthwhile to ship such stuff. If you have a brute-force stardrive it probably isn't.)
Note that this is a very dangerous star system to be in, the white dwarf will periodically nova (although a sufficiently advanced science should be able to predict the detonations) and if it sucks down enough matter it will be even worse when it collapses down to a neutron star. You also have the jets from the other neutron star or black hole, although they could be aimed in a safe direction.
$endgroup$
add a comment |
$begingroup$
I think I see a scenario that could produce your world. Note that this is cataclysmic on an interstellar scale--life on nearby stars would have been eradicated.
We need a system that starts out with three stars, two of which are a close binary and each star exceeds (but not by too much) 8 solar masses. The third star is more distant and somewhat smaller.
The two big stars burn through their fuel and supernova, leaving behind neutron stars. The third is abused by these detonations but survives. The neutron stars are like their parents--a close binary. In time they spiral in and go splat--but enough mass is thrown off in the process to make your high-G world, from which a planet is born. (Note that I'm not sure it's possible for it to end up in a planet. The process is extremely energetic, it might be ejected too fast.)
Now you have a neutron star or black hole, a super-planet and an ordinary star. Now it's time for our third star to die--this time more peacefully, to a white dwarf.
This collection of debris encounters another star which ends up captured, the super-planet ending up in the life zone of the new star. The white dwarf sucks in matter from this fourth star, eventually you get a nova. This scours the atmosphere off the super-planet.
You're now left with a super-planet with no atmosphere. It's going to be an incredibly dense world as much of the stuff thrown off from the neutron star impact is from the lower part of the periodic table.
While you didn't ask for it this is going to be an immensely valuable source of heavy metals. (This is assuming it's worthwhile to ship such stuff. If you have a brute-force stardrive it probably isn't.)
Note that this is a very dangerous star system to be in, the white dwarf will periodically nova (although a sufficiently advanced science should be able to predict the detonations) and if it sucks down enough matter it will be even worse when it collapses down to a neutron star. You also have the jets from the other neutron star or black hole, although they could be aimed in a safe direction.
$endgroup$
I think I see a scenario that could produce your world. Note that this is cataclysmic on an interstellar scale--life on nearby stars would have been eradicated.
We need a system that starts out with three stars, two of which are a close binary and each star exceeds (but not by too much) 8 solar masses. The third star is more distant and somewhat smaller.
The two big stars burn through their fuel and supernova, leaving behind neutron stars. The third is abused by these detonations but survives. The neutron stars are like their parents--a close binary. In time they spiral in and go splat--but enough mass is thrown off in the process to make your high-G world, from which a planet is born. (Note that I'm not sure it's possible for it to end up in a planet. The process is extremely energetic, it might be ejected too fast.)
Now you have a neutron star or black hole, a super-planet and an ordinary star. Now it's time for our third star to die--this time more peacefully, to a white dwarf.
This collection of debris encounters another star which ends up captured, the super-planet ending up in the life zone of the new star. The white dwarf sucks in matter from this fourth star, eventually you get a nova. This scours the atmosphere off the super-planet.
You're now left with a super-planet with no atmosphere. It's going to be an incredibly dense world as much of the stuff thrown off from the neutron star impact is from the lower part of the periodic table.
While you didn't ask for it this is going to be an immensely valuable source of heavy metals. (This is assuming it's worthwhile to ship such stuff. If you have a brute-force stardrive it probably isn't.)
Note that this is a very dangerous star system to be in, the white dwarf will periodically nova (although a sufficiently advanced science should be able to predict the detonations) and if it sucks down enough matter it will be even worse when it collapses down to a neutron star. You also have the jets from the other neutron star or black hole, although they could be aimed in a safe direction.
answered 2 days ago
Loren PechtelLoren Pechtel
19.8k2262
19.8k2262
add a comment |
add a comment |
$begingroup$
Heavy metal world.
- 12G planet. You could ramp up the gravity by making the core more dense. Our planet has an iron / nickel core under the rocks, and those have atomic weights of 55 and 58. Uranium has an atomic weight of 238. So if you made the core out of uranium and other heavy friends your density is 5x that of earth. Those elements are rarer than iron but not crazy rare. Now your planet only needs to be 2.4x as big as earth to have your 12G. If you want your planet even smaller, you can invoke the stable superheavy elements from the undiscovered far reaches of the periodic table - the island of stability
There could be other cool things about the uranium planet. Maybe natural fission goes on deep inside, which would make for rocking volcanoes. Could you take advantage of this to get off planet? Hmm... Also, the atmosphere would have a lot of radon, which would give everyone very low voices among other things.
- My understanding of atmosphere is that you need a magnetosphere to keep it in, gravity notwithstanding. Otherwise the solar wind will strip it away. Mars lost its magnetosphere and then lost its atmosphere because of that. No reason to think that the heavy planet would not have a magnetosphere.
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2
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
2
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
1
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
add a comment |
$begingroup$
Heavy metal world.
- 12G planet. You could ramp up the gravity by making the core more dense. Our planet has an iron / nickel core under the rocks, and those have atomic weights of 55 and 58. Uranium has an atomic weight of 238. So if you made the core out of uranium and other heavy friends your density is 5x that of earth. Those elements are rarer than iron but not crazy rare. Now your planet only needs to be 2.4x as big as earth to have your 12G. If you want your planet even smaller, you can invoke the stable superheavy elements from the undiscovered far reaches of the periodic table - the island of stability
There could be other cool things about the uranium planet. Maybe natural fission goes on deep inside, which would make for rocking volcanoes. Could you take advantage of this to get off planet? Hmm... Also, the atmosphere would have a lot of radon, which would give everyone very low voices among other things.
- My understanding of atmosphere is that you need a magnetosphere to keep it in, gravity notwithstanding. Otherwise the solar wind will strip it away. Mars lost its magnetosphere and then lost its atmosphere because of that. No reason to think that the heavy planet would not have a magnetosphere.
$endgroup$
2
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
2
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
1
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
add a comment |
$begingroup$
Heavy metal world.
- 12G planet. You could ramp up the gravity by making the core more dense. Our planet has an iron / nickel core under the rocks, and those have atomic weights of 55 and 58. Uranium has an atomic weight of 238. So if you made the core out of uranium and other heavy friends your density is 5x that of earth. Those elements are rarer than iron but not crazy rare. Now your planet only needs to be 2.4x as big as earth to have your 12G. If you want your planet even smaller, you can invoke the stable superheavy elements from the undiscovered far reaches of the periodic table - the island of stability
There could be other cool things about the uranium planet. Maybe natural fission goes on deep inside, which would make for rocking volcanoes. Could you take advantage of this to get off planet? Hmm... Also, the atmosphere would have a lot of radon, which would give everyone very low voices among other things.
- My understanding of atmosphere is that you need a magnetosphere to keep it in, gravity notwithstanding. Otherwise the solar wind will strip it away. Mars lost its magnetosphere and then lost its atmosphere because of that. No reason to think that the heavy planet would not have a magnetosphere.
$endgroup$
Heavy metal world.
- 12G planet. You could ramp up the gravity by making the core more dense. Our planet has an iron / nickel core under the rocks, and those have atomic weights of 55 and 58. Uranium has an atomic weight of 238. So if you made the core out of uranium and other heavy friends your density is 5x that of earth. Those elements are rarer than iron but not crazy rare. Now your planet only needs to be 2.4x as big as earth to have your 12G. If you want your planet even smaller, you can invoke the stable superheavy elements from the undiscovered far reaches of the periodic table - the island of stability
There could be other cool things about the uranium planet. Maybe natural fission goes on deep inside, which would make for rocking volcanoes. Could you take advantage of this to get off planet? Hmm... Also, the atmosphere would have a lot of radon, which would give everyone very low voices among other things.
- My understanding of atmosphere is that you need a magnetosphere to keep it in, gravity notwithstanding. Otherwise the solar wind will strip it away. Mars lost its magnetosphere and then lost its atmosphere because of that. No reason to think that the heavy planet would not have a magnetosphere.
answered 2 days ago
WillkWillk
115k27218482
115k27218482
2
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
2
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
1
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
add a comment |
2
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
2
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
1
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
2
2
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
$begingroup$
Important to bear in mind that a planet whose core was composed of uranium would detonate. Furthermore, neither the uranium planet nor one composed of transuranic elements from the 'island of stability', can form in nature.
$endgroup$
– Arkenstein XII
2 days ago
2
2
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
$begingroup$
Only if it had significant U-235, Uranium-238 is really no danger.
$endgroup$
– user2617804
yesterday
1
1
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
$begingroup$
While the core is important, don't forget to account for the amount of comparatively light elements in the mantle that are making up the actual bulk of Earth's mass and volume. - Swap out all the oxygen, silicon, and friends for stuff nearer lead, and the nickle and iron for something even heavier...
$endgroup$
– TheLuckless
yesterday
add a comment |
Sean Kindle is a new contributor. Be nice, and check out our Code of Conduct.
Sean Kindle is a new contributor. Be nice, and check out our Code of Conduct.
Sean Kindle is a new contributor. Be nice, and check out our Code of Conduct.
Sean Kindle is a new contributor. Be nice, and check out our Code of Conduct.
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$begingroup$
Hi Sean, welcome to Worldbuilding.SE. You're asking two separate questions here. Could you please remove the second one (about escaping)? You are welcome to ask it in a new question, if it's not a duplicate. Thanks!
$endgroup$
– Cyn
2 days ago
$begingroup$
Easy : a planet which is so near it’s star that not only it’s atmosphere was blowed up but with it’s ground starting to melt.
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– user2284570
2 days ago
$begingroup$
Sean, one detail. 12G is incredibly high for a planet; it's unrealistic. Like, "4G" is huge.
$endgroup$
– Fattie
yesterday