Mixing
Reduced gravity on surface of planet
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up vote
1
down vote
favorite
This is a simple question, hopefully not broad.
My colonizing company wants to put little habitats on the surface of a planet with more gravity (2.0G) than earth.
Is there a way to reduce gravity to 1G in a little 'houses' on the surface of a planet?
What would the buildings look like?
gravity construction infrastructure
asked 7 hours ago
Aaron
326
add a comment |Â
up vote
1
down vote
favorite
This is a simple question, hopefully not broad.
My colonizing company wants to put little habitats on the surface of a planet with more gravity (2.0G) than earth.
Is there a way to reduce gravity to 1G in a little 'houses' on the surface of a planet?
What would the buildings look like?
gravity construction infrastructure
asked 7 hours ago
Aaron
326
What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
1
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago
add a comment |Â
up vote
1
down vote
favorite
up vote
1
down vote
favorite
This is a simple question, hopefully not broad.
My colonizing company wants to put little habitats on the surface of a planet with more gravity (2.0G) than earth.
Is there a way to reduce gravity to 1G in a little 'houses' on the surface of a planet?
What would the buildings look like?
gravity construction infrastructure
asked 7 hours ago
Aaron
326
This is a simple question, hopefully not broad.
My colonizing company wants to put little habitats on the surface of a planet with more gravity (2.0G) than earth.
Is there a way to reduce gravity to 1G in a little 'houses' on the surface of a planet?
What would the buildings look like?
gravity construction infrastructure
gravity construction infrastructure
asked 7 hours ago
Aaron
326
asked 7 hours ago
Aaron
326
asked 7 hours ago
Aaron
326
asked 7 hours ago
Aaron
326
asked 7 hours ago
Aaron
326
326
What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
1
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago
add a comment |Â
What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
1
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago
What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
1
1
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago
add a comment |Â
6 Answers
6
active
oldest
votes
up vote
2
down vote
accepted
Here are some ideas of how you could achieve 1G houses, though these either aren't on the surface or aren't really near-future levels of technology:
Antigravity tech. This would obviously solve the problem - just turn down the strength of the antigravity to allow 1G to still affect everyone. This probably doesn't count as near-future tech though.
Inertial dampeners or force fields. If you have tech to allow a spaceship to accelerate at high Gs without squishing the crew, it seems reasonable to be able to apply that to preventing a planet's gravity from squishing people. Force fields are one way this could be implemented - if you can apply force at a distance, apply enough force to counteract 1G. Again, this might not count as near-future tech, but if you've already got them in your setting you can just apply them to solve your problem.
Stilts. If you have a space elevator then you'd be using it to lift people and materials to the point where they're in orbit. When you're in orbit you're in perpetual freefall, so you feel like you're in 0G. Halfway up the elevator, you'd feel 1G. They're not exactly on the surface, but space elevators feel more near-future tech than the first two options.
Live deep underground. If you went to the very center of a planet there would be roughly an equal amount of mass in each direction, so you would not feel any gravity. If you went partway to the center of the planet (I'm not sure if it's more or less than halfway to the core), there's a point where the next effect of gravity would be 1G. Again, not on the surface, but resisting the conditions there might qualify as near-future tech.
answered 7 hours ago
Rob Watts
15.7k33675
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
add a comment |Â
up vote
4
down vote
You could try angular momentum
ULtimately, even with near future technology, we won't be able to reduce gravity directly. There's still too much about this fundamental force that we don't know and there's even a possibility that we may never be able to incorporate it into a Grand Unified Theory (GUT) of universal fundamental forces.
But, you can counteract it somewhat.
Let's say you have a method for increasing the spin of your planet. By many orders of magnitude. (You could do this with thrusters on opposite sides of the planet for instance, but realistically this is going to take energy levels beyond what we can currently harness.) In such a case, you could increase the centrifugal force of the planet, ultimately counteracting gravity somewhat.
It should be noted that you have several concerns with this approach. The first is that if you don't bring the atmosphere along for the ride somehow, you're in for a very difficult time because of the massive winds. Even if you do, you're probably going to increase the Coriolis Effect massively on your planet. Also, landing on this planet is going to be a lot harder because it's now spinning so fast. You have to match your orbital velocity to the angular momentum of the planet.
Ultimately it's going to be a weird experience for your colonists and I don't even have a frame of reference for what it would feel like. Some things will just feel like reduced gravity, others not so much. Also, there could be noticeable differences in the feeling of gravity at different altitudes (less gravity the higher you go), meaning that you'd have to set your spin for the majority of the population.
Is this possible? Yes. Is it practical, even with near future technology? No. This is entirely speculative in point of fact. Please don't try this at home.
answered 7 hours ago
Tim B II
22.6k64997
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
add a comment |Â
up vote
2
down vote
In the realm of real science, no.
However if you are open to a little bit of hand waving the imaginary substance of "Cavorite" is widely used in fiction as a substance which can "block" the force of gravity. This assumes a Newtonian view of gravity and doesn't really make sense if you accept the relativistic view.
You could theoretically make a Cavorite mesh to be able to block an portion of the gravity that you wish. I think embedding this mesh into the foundation of the habitat would be the way to go.
answered 7 hours ago
Mathaddict
1,559114
add a comment |Â
up vote
2
down vote
I posit cities (collections of homes) built within a rapidly rotating ring about the planet.
In essence, and by your constraints of known science, what you want is to lessen gravity not in the direction of gravitational acceleration of the planet, but in the opposite direction and then some. Your cities could exist inside a large vacuum tube perhaps separated from the tube walls by magnetic forces. The city structures would then need to be accelerated in one direction until they reach orbital velocity at the "surface" of the planet (or, where ever you decide the cities should be on the planet). They are essentially orbiting inside the atmosphere, only separated by some intermittent vacuum.
Moving at orbital velocity, the cities would experience zero-gee, that is, until you continued to accelerate them further. Cross above orbital velocity, and the citizens of the city would begin to experience a pull in the opposite direction of planetary gravity; think of a ball on a string being whirled around. If not for the air, there would exist a velocity where the ball's rotational forces and the forces acting to pull it nearer the origin would cancel out, i.e., orbital velocity. Accelerate it more, and it pulls against the string, experiencing an outward force.
Your cities would be upside down and flying through a vacuum tube at greater than orbital velocity inside the atmosphere, crust, on the surface, whathaveyou. If you tune the magnetic levitation to resist the city from crashing into the tube walls, and if you can magnetically propel your city through the tube, then all your city designers need to do is fine-tune the acceleration to match whatever "gravitational acceleration" your citizens want to live under. Again, this acceleration would be felt in the opposite direction of planetary acceleration, but planetary acceleration would not be felt due to the forces canceling out and then going over that canceling limit.
If you'd like me to elaborate or better explain something, or expand on some other untouched aspect of this, please let me know.
answered 7 hours ago
B.fox
6811212
add a comment |Â
up vote
0
down vote
You've certainly heard of using rotating habitats in orbit to fake gravity, correct? This can be used on the planet's surface as well. But instead of being a circular habitat, its a parabolic habitat. The centrifugal force vector and the gravitational force vector add together. If the habitat is upside-down, the centrifugal force vector and the gravity vector cancel each other out. So to get 1G, the upside-down habitat needs to spin fast enough to generate 3G.
answered 7 hours ago
Ryan_L
3,568722
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
add a comment |Â
up vote
0
down vote
On earth, at altitudes of ~1600 mi/ 2600 km 1/2 gravity is achieved. at this altitude medium earth orbits are possible.
Well shielded habitats would allow a comfortable resting environment, while any necessary on-planet industry could be facilitated with robots and human prosthesetics.
Perhaps a hardy sub-population wants to make a go of it on-surface at 2G, as well.
Changing the planetary gravity isn't worth the trouble, unless you have a plethora of handwavium.
answered 3 hours ago
theRiley
2828
add a comment |Â
6 Answers
6
active
oldest
votes
6 Answers
6
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
2
down vote
accepted
Here are some ideas of how you could achieve 1G houses, though these either aren't on the surface or aren't really near-future levels of technology:
Antigravity tech. This would obviously solve the problem - just turn down the strength of the antigravity to allow 1G to still affect everyone. This probably doesn't count as near-future tech though.
Inertial dampeners or force fields. If you have tech to allow a spaceship to accelerate at high Gs without squishing the crew, it seems reasonable to be able to apply that to preventing a planet's gravity from squishing people. Force fields are one way this could be implemented - if you can apply force at a distance, apply enough force to counteract 1G. Again, this might not count as near-future tech, but if you've already got them in your setting you can just apply them to solve your problem.
Stilts. If you have a space elevator then you'd be using it to lift people and materials to the point where they're in orbit. When you're in orbit you're in perpetual freefall, so you feel like you're in 0G. Halfway up the elevator, you'd feel 1G. They're not exactly on the surface, but space elevators feel more near-future tech than the first two options.
Live deep underground. If you went to the very center of a planet there would be roughly an equal amount of mass in each direction, so you would not feel any gravity. If you went partway to the center of the planet (I'm not sure if it's more or less than halfway to the core), there's a point where the next effect of gravity would be 1G. Again, not on the surface, but resisting the conditions there might qualify as near-future tech.
answered 7 hours ago
Rob Watts
15.7k33675
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
add a comment |Â
up vote
2
down vote
accepted
Here are some ideas of how you could achieve 1G houses, though these either aren't on the surface or aren't really near-future levels of technology:
Antigravity tech. This would obviously solve the problem - just turn down the strength of the antigravity to allow 1G to still affect everyone. This probably doesn't count as near-future tech though.
Inertial dampeners or force fields. If you have tech to allow a spaceship to accelerate at high Gs without squishing the crew, it seems reasonable to be able to apply that to preventing a planet's gravity from squishing people. Force fields are one way this could be implemented - if you can apply force at a distance, apply enough force to counteract 1G. Again, this might not count as near-future tech, but if you've already got them in your setting you can just apply them to solve your problem.
Stilts. If you have a space elevator then you'd be using it to lift people and materials to the point where they're in orbit. When you're in orbit you're in perpetual freefall, so you feel like you're in 0G. Halfway up the elevator, you'd feel 1G. They're not exactly on the surface, but space elevators feel more near-future tech than the first two options.
Live deep underground. If you went to the very center of a planet there would be roughly an equal amount of mass in each direction, so you would not feel any gravity. If you went partway to the center of the planet (I'm not sure if it's more or less than halfway to the core), there's a point where the next effect of gravity would be 1G. Again, not on the surface, but resisting the conditions there might qualify as near-future tech.
answered 7 hours ago
Rob Watts
15.7k33675
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
add a comment |Â
up vote
2
down vote
accepted
up vote
2
down vote
accepted
Here are some ideas of how you could achieve 1G houses, though these either aren't on the surface or aren't really near-future levels of technology:
Antigravity tech. This would obviously solve the problem - just turn down the strength of the antigravity to allow 1G to still affect everyone. This probably doesn't count as near-future tech though.
Inertial dampeners or force fields. If you have tech to allow a spaceship to accelerate at high Gs without squishing the crew, it seems reasonable to be able to apply that to preventing a planet's gravity from squishing people. Force fields are one way this could be implemented - if you can apply force at a distance, apply enough force to counteract 1G. Again, this might not count as near-future tech, but if you've already got them in your setting you can just apply them to solve your problem.
Stilts. If you have a space elevator then you'd be using it to lift people and materials to the point where they're in orbit. When you're in orbit you're in perpetual freefall, so you feel like you're in 0G. Halfway up the elevator, you'd feel 1G. They're not exactly on the surface, but space elevators feel more near-future tech than the first two options.
Live deep underground. If you went to the very center of a planet there would be roughly an equal amount of mass in each direction, so you would not feel any gravity. If you went partway to the center of the planet (I'm not sure if it's more or less than halfway to the core), there's a point where the next effect of gravity would be 1G. Again, not on the surface, but resisting the conditions there might qualify as near-future tech.
answered 7 hours ago
Rob Watts
15.7k33675
Here are some ideas of how you could achieve 1G houses, though these either aren't on the surface or aren't really near-future levels of technology:
Antigravity tech. This would obviously solve the problem - just turn down the strength of the antigravity to allow 1G to still affect everyone. This probably doesn't count as near-future tech though.
Inertial dampeners or force fields. If you have tech to allow a spaceship to accelerate at high Gs without squishing the crew, it seems reasonable to be able to apply that to preventing a planet's gravity from squishing people. Force fields are one way this could be implemented - if you can apply force at a distance, apply enough force to counteract 1G. Again, this might not count as near-future tech, but if you've already got them in your setting you can just apply them to solve your problem.
Stilts. If you have a space elevator then you'd be using it to lift people and materials to the point where they're in orbit. When you're in orbit you're in perpetual freefall, so you feel like you're in 0G. Halfway up the elevator, you'd feel 1G. They're not exactly on the surface, but space elevators feel more near-future tech than the first two options.
Live deep underground. If you went to the very center of a planet there would be roughly an equal amount of mass in each direction, so you would not feel any gravity. If you went partway to the center of the planet (I'm not sure if it's more or less than halfway to the core), there's a point where the next effect of gravity would be 1G. Again, not on the surface, but resisting the conditions there might qualify as near-future tech.
answered 7 hours ago
Rob Watts
15.7k33675
answered 7 hours ago
Rob Watts
15.7k33675
answered 7 hours ago
Rob Watts
15.7k33675
answered 7 hours ago
Rob Watts
15.7k33675
15.7k33675
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
add a comment |Â
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
Gravity would vary linearly with depth into the planet so you're correct in 4 that halfway down would be 1g (assuming density roughly constant). In 3 you're not correct that halfway up would feel like 1g. Since gravity decreases with the square of distance I think you'd have to be something like root(2)*(planet radius) up the space elevator to feel 1g.
– ben
6 hours ago
add a comment |Â
up vote
4
down vote
You could try angular momentum
ULtimately, even with near future technology, we won't be able to reduce gravity directly. There's still too much about this fundamental force that we don't know and there's even a possibility that we may never be able to incorporate it into a Grand Unified Theory (GUT) of universal fundamental forces.
But, you can counteract it somewhat.
Let's say you have a method for increasing the spin of your planet. By many orders of magnitude. (You could do this with thrusters on opposite sides of the planet for instance, but realistically this is going to take energy levels beyond what we can currently harness.) In such a case, you could increase the centrifugal force of the planet, ultimately counteracting gravity somewhat.
It should be noted that you have several concerns with this approach. The first is that if you don't bring the atmosphere along for the ride somehow, you're in for a very difficult time because of the massive winds. Even if you do, you're probably going to increase the Coriolis Effect massively on your planet. Also, landing on this planet is going to be a lot harder because it's now spinning so fast. You have to match your orbital velocity to the angular momentum of the planet.
Ultimately it's going to be a weird experience for your colonists and I don't even have a frame of reference for what it would feel like. Some things will just feel like reduced gravity, others not so much. Also, there could be noticeable differences in the feeling of gravity at different altitudes (less gravity the higher you go), meaning that you'd have to set your spin for the majority of the population.
Is this possible? Yes. Is it practical, even with near future technology? No. This is entirely speculative in point of fact. Please don't try this at home.
answered 7 hours ago
Tim B II
22.6k64997
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
add a comment |Â
up vote
4
down vote
You could try angular momentum
ULtimately, even with near future technology, we won't be able to reduce gravity directly. There's still too much about this fundamental force that we don't know and there's even a possibility that we may never be able to incorporate it into a Grand Unified Theory (GUT) of universal fundamental forces.
But, you can counteract it somewhat.
Let's say you have a method for increasing the spin of your planet. By many orders of magnitude. (You could do this with thrusters on opposite sides of the planet for instance, but realistically this is going to take energy levels beyond what we can currently harness.) In such a case, you could increase the centrifugal force of the planet, ultimately counteracting gravity somewhat.
It should be noted that you have several concerns with this approach. The first is that if you don't bring the atmosphere along for the ride somehow, you're in for a very difficult time because of the massive winds. Even if you do, you're probably going to increase the Coriolis Effect massively on your planet. Also, landing on this planet is going to be a lot harder because it's now spinning so fast. You have to match your orbital velocity to the angular momentum of the planet.
Ultimately it's going to be a weird experience for your colonists and I don't even have a frame of reference for what it would feel like. Some things will just feel like reduced gravity, others not so much. Also, there could be noticeable differences in the feeling of gravity at different altitudes (less gravity the higher you go), meaning that you'd have to set your spin for the majority of the population.
Is this possible? Yes. Is it practical, even with near future technology? No. This is entirely speculative in point of fact. Please don't try this at home.
answered 7 hours ago
Tim B II
22.6k64997
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
add a comment |Â
up vote
4
down vote
up vote
4
down vote
You could try angular momentum
ULtimately, even with near future technology, we won't be able to reduce gravity directly. There's still too much about this fundamental force that we don't know and there's even a possibility that we may never be able to incorporate it into a Grand Unified Theory (GUT) of universal fundamental forces.
But, you can counteract it somewhat.
Let's say you have a method for increasing the spin of your planet. By many orders of magnitude. (You could do this with thrusters on opposite sides of the planet for instance, but realistically this is going to take energy levels beyond what we can currently harness.) In such a case, you could increase the centrifugal force of the planet, ultimately counteracting gravity somewhat.
It should be noted that you have several concerns with this approach. The first is that if you don't bring the atmosphere along for the ride somehow, you're in for a very difficult time because of the massive winds. Even if you do, you're probably going to increase the Coriolis Effect massively on your planet. Also, landing on this planet is going to be a lot harder because it's now spinning so fast. You have to match your orbital velocity to the angular momentum of the planet.
Ultimately it's going to be a weird experience for your colonists and I don't even have a frame of reference for what it would feel like. Some things will just feel like reduced gravity, others not so much. Also, there could be noticeable differences in the feeling of gravity at different altitudes (less gravity the higher you go), meaning that you'd have to set your spin for the majority of the population.
Is this possible? Yes. Is it practical, even with near future technology? No. This is entirely speculative in point of fact. Please don't try this at home.
answered 7 hours ago
Tim B II
22.6k64997
You could try angular momentum
ULtimately, even with near future technology, we won't be able to reduce gravity directly. There's still too much about this fundamental force that we don't know and there's even a possibility that we may never be able to incorporate it into a Grand Unified Theory (GUT) of universal fundamental forces.
But, you can counteract it somewhat.
Let's say you have a method for increasing the spin of your planet. By many orders of magnitude. (You could do this with thrusters on opposite sides of the planet for instance, but realistically this is going to take energy levels beyond what we can currently harness.) In such a case, you could increase the centrifugal force of the planet, ultimately counteracting gravity somewhat.
It should be noted that you have several concerns with this approach. The first is that if you don't bring the atmosphere along for the ride somehow, you're in for a very difficult time because of the massive winds. Even if you do, you're probably going to increase the Coriolis Effect massively on your planet. Also, landing on this planet is going to be a lot harder because it's now spinning so fast. You have to match your orbital velocity to the angular momentum of the planet.
Ultimately it's going to be a weird experience for your colonists and I don't even have a frame of reference for what it would feel like. Some things will just feel like reduced gravity, others not so much. Also, there could be noticeable differences in the feeling of gravity at different altitudes (less gravity the higher you go), meaning that you'd have to set your spin for the majority of the population.
Is this possible? Yes. Is it practical, even with near future technology? No. This is entirely speculative in point of fact. Please don't try this at home.
answered 7 hours ago
Tim B II
22.6k64997
answered 7 hours ago
Tim B II
22.6k64997
answered 7 hours ago
Tim B II
22.6k64997
answered 7 hours ago
Tim B II
22.6k64997
22.6k64997
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
add a comment |Â
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
I want to see a detailed analysis of what spinning up a planet to counteract half its gravity would do - the tectonic effects could be quite spectacular. The pressure on the core near the poles wouldn't change but the pressure around the equator would decrease, so it might look more like a disk than a sphere. My hunch is that you'd have to wait for a while before the volcanoes, etc. calmed down enough for the planet to be habitable again.
– Rob Watts
6 hours ago
2
2
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
This is the only answer I've seen that directly answers the question (make it 1G on the surface - at least at the equator) and is possible within the known laws of physics. Well, the only one that doesn't also involve nightmare carnival rides anyway...
– ben
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
@RobWatts yes, I'd forgotten latitude as a factor but you're completely right on that point. If it's an ocean world, you'd also have to wait for the centrifugal force on the oceans to stabilise just to see where the new continents sit. Generally this would be very disruptive and you'd probably need to take a long term approach on this (say, 1000 years)
– Tim B II
6 hours ago
add a comment |Â
up vote
2
down vote
In the realm of real science, no.
However if you are open to a little bit of hand waving the imaginary substance of "Cavorite" is widely used in fiction as a substance which can "block" the force of gravity. This assumes a Newtonian view of gravity and doesn't really make sense if you accept the relativistic view.
You could theoretically make a Cavorite mesh to be able to block an portion of the gravity that you wish. I think embedding this mesh into the foundation of the habitat would be the way to go.
answered 7 hours ago
Mathaddict
1,559114
add a comment |Â
up vote
2
down vote
In the realm of real science, no.
However if you are open to a little bit of hand waving the imaginary substance of "Cavorite" is widely used in fiction as a substance which can "block" the force of gravity. This assumes a Newtonian view of gravity and doesn't really make sense if you accept the relativistic view.
You could theoretically make a Cavorite mesh to be able to block an portion of the gravity that you wish. I think embedding this mesh into the foundation of the habitat would be the way to go.
answered 7 hours ago
Mathaddict
1,559114
add a comment |Â
up vote
2
down vote
up vote
2
down vote
In the realm of real science, no.
However if you are open to a little bit of hand waving the imaginary substance of "Cavorite" is widely used in fiction as a substance which can "block" the force of gravity. This assumes a Newtonian view of gravity and doesn't really make sense if you accept the relativistic view.
You could theoretically make a Cavorite mesh to be able to block an portion of the gravity that you wish. I think embedding this mesh into the foundation of the habitat would be the way to go.
answered 7 hours ago
Mathaddict
1,559114
In the realm of real science, no.
However if you are open to a little bit of hand waving the imaginary substance of "Cavorite" is widely used in fiction as a substance which can "block" the force of gravity. This assumes a Newtonian view of gravity and doesn't really make sense if you accept the relativistic view.
You could theoretically make a Cavorite mesh to be able to block an portion of the gravity that you wish. I think embedding this mesh into the foundation of the habitat would be the way to go.
answered 7 hours ago
Mathaddict
1,559114
answered 7 hours ago
Mathaddict
1,559114
answered 7 hours ago
Mathaddict
1,559114
answered 7 hours ago
Mathaddict
1,559114
1,559114
add a comment |Â
add a comment |Â
up vote
2
down vote
I posit cities (collections of homes) built within a rapidly rotating ring about the planet.
In essence, and by your constraints of known science, what you want is to lessen gravity not in the direction of gravitational acceleration of the planet, but in the opposite direction and then some. Your cities could exist inside a large vacuum tube perhaps separated from the tube walls by magnetic forces. The city structures would then need to be accelerated in one direction until they reach orbital velocity at the "surface" of the planet (or, where ever you decide the cities should be on the planet). They are essentially orbiting inside the atmosphere, only separated by some intermittent vacuum.
Moving at orbital velocity, the cities would experience zero-gee, that is, until you continued to accelerate them further. Cross above orbital velocity, and the citizens of the city would begin to experience a pull in the opposite direction of planetary gravity; think of a ball on a string being whirled around. If not for the air, there would exist a velocity where the ball's rotational forces and the forces acting to pull it nearer the origin would cancel out, i.e., orbital velocity. Accelerate it more, and it pulls against the string, experiencing an outward force.
Your cities would be upside down and flying through a vacuum tube at greater than orbital velocity inside the atmosphere, crust, on the surface, whathaveyou. If you tune the magnetic levitation to resist the city from crashing into the tube walls, and if you can magnetically propel your city through the tube, then all your city designers need to do is fine-tune the acceleration to match whatever "gravitational acceleration" your citizens want to live under. Again, this acceleration would be felt in the opposite direction of planetary acceleration, but planetary acceleration would not be felt due to the forces canceling out and then going over that canceling limit.
If you'd like me to elaborate or better explain something, or expand on some other untouched aspect of this, please let me know.
answered 7 hours ago
B.fox
6811212
add a comment |Â
up vote
2
down vote
I posit cities (collections of homes) built within a rapidly rotating ring about the planet.
In essence, and by your constraints of known science, what you want is to lessen gravity not in the direction of gravitational acceleration of the planet, but in the opposite direction and then some. Your cities could exist inside a large vacuum tube perhaps separated from the tube walls by magnetic forces. The city structures would then need to be accelerated in one direction until they reach orbital velocity at the "surface" of the planet (or, where ever you decide the cities should be on the planet). They are essentially orbiting inside the atmosphere, only separated by some intermittent vacuum.
Moving at orbital velocity, the cities would experience zero-gee, that is, until you continued to accelerate them further. Cross above orbital velocity, and the citizens of the city would begin to experience a pull in the opposite direction of planetary gravity; think of a ball on a string being whirled around. If not for the air, there would exist a velocity where the ball's rotational forces and the forces acting to pull it nearer the origin would cancel out, i.e., orbital velocity. Accelerate it more, and it pulls against the string, experiencing an outward force.
Your cities would be upside down and flying through a vacuum tube at greater than orbital velocity inside the atmosphere, crust, on the surface, whathaveyou. If you tune the magnetic levitation to resist the city from crashing into the tube walls, and if you can magnetically propel your city through the tube, then all your city designers need to do is fine-tune the acceleration to match whatever "gravitational acceleration" your citizens want to live under. Again, this acceleration would be felt in the opposite direction of planetary acceleration, but planetary acceleration would not be felt due to the forces canceling out and then going over that canceling limit.
If you'd like me to elaborate or better explain something, or expand on some other untouched aspect of this, please let me know.
answered 7 hours ago
B.fox
6811212
add a comment |Â
up vote
2
down vote
up vote
2
down vote
I posit cities (collections of homes) built within a rapidly rotating ring about the planet.
In essence, and by your constraints of known science, what you want is to lessen gravity not in the direction of gravitational acceleration of the planet, but in the opposite direction and then some. Your cities could exist inside a large vacuum tube perhaps separated from the tube walls by magnetic forces. The city structures would then need to be accelerated in one direction until they reach orbital velocity at the "surface" of the planet (or, where ever you decide the cities should be on the planet). They are essentially orbiting inside the atmosphere, only separated by some intermittent vacuum.
Moving at orbital velocity, the cities would experience zero-gee, that is, until you continued to accelerate them further. Cross above orbital velocity, and the citizens of the city would begin to experience a pull in the opposite direction of planetary gravity; think of a ball on a string being whirled around. If not for the air, there would exist a velocity where the ball's rotational forces and the forces acting to pull it nearer the origin would cancel out, i.e., orbital velocity. Accelerate it more, and it pulls against the string, experiencing an outward force.
Your cities would be upside down and flying through a vacuum tube at greater than orbital velocity inside the atmosphere, crust, on the surface, whathaveyou. If you tune the magnetic levitation to resist the city from crashing into the tube walls, and if you can magnetically propel your city through the tube, then all your city designers need to do is fine-tune the acceleration to match whatever "gravitational acceleration" your citizens want to live under. Again, this acceleration would be felt in the opposite direction of planetary acceleration, but planetary acceleration would not be felt due to the forces canceling out and then going over that canceling limit.
If you'd like me to elaborate or better explain something, or expand on some other untouched aspect of this, please let me know.
answered 7 hours ago
B.fox
6811212
I posit cities (collections of homes) built within a rapidly rotating ring about the planet.
In essence, and by your constraints of known science, what you want is to lessen gravity not in the direction of gravitational acceleration of the planet, but in the opposite direction and then some. Your cities could exist inside a large vacuum tube perhaps separated from the tube walls by magnetic forces. The city structures would then need to be accelerated in one direction until they reach orbital velocity at the "surface" of the planet (or, where ever you decide the cities should be on the planet). They are essentially orbiting inside the atmosphere, only separated by some intermittent vacuum.
Moving at orbital velocity, the cities would experience zero-gee, that is, until you continued to accelerate them further. Cross above orbital velocity, and the citizens of the city would begin to experience a pull in the opposite direction of planetary gravity; think of a ball on a string being whirled around. If not for the air, there would exist a velocity where the ball's rotational forces and the forces acting to pull it nearer the origin would cancel out, i.e., orbital velocity. Accelerate it more, and it pulls against the string, experiencing an outward force.
Your cities would be upside down and flying through a vacuum tube at greater than orbital velocity inside the atmosphere, crust, on the surface, whathaveyou. If you tune the magnetic levitation to resist the city from crashing into the tube walls, and if you can magnetically propel your city through the tube, then all your city designers need to do is fine-tune the acceleration to match whatever "gravitational acceleration" your citizens want to live under. Again, this acceleration would be felt in the opposite direction of planetary acceleration, but planetary acceleration would not be felt due to the forces canceling out and then going over that canceling limit.
If you'd like me to elaborate or better explain something, or expand on some other untouched aspect of this, please let me know.
answered 7 hours ago
B.fox
6811212
answered 7 hours ago
B.fox
6811212
answered 7 hours ago
B.fox
6811212
answered 7 hours ago
B.fox
6811212
6811212
add a comment |Â
add a comment |Â
up vote
0
down vote
You've certainly heard of using rotating habitats in orbit to fake gravity, correct? This can be used on the planet's surface as well. But instead of being a circular habitat, its a parabolic habitat. The centrifugal force vector and the gravitational force vector add together. If the habitat is upside-down, the centrifugal force vector and the gravity vector cancel each other out. So to get 1G, the upside-down habitat needs to spin fast enough to generate 3G.
answered 7 hours ago
Ryan_L
3,568722
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
add a comment |Â
up vote
0
down vote
You've certainly heard of using rotating habitats in orbit to fake gravity, correct? This can be used on the planet's surface as well. But instead of being a circular habitat, its a parabolic habitat. The centrifugal force vector and the gravitational force vector add together. If the habitat is upside-down, the centrifugal force vector and the gravity vector cancel each other out. So to get 1G, the upside-down habitat needs to spin fast enough to generate 3G.
answered 7 hours ago
Ryan_L
3,568722
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
add a comment |Â
up vote
0
down vote
up vote
0
down vote
You've certainly heard of using rotating habitats in orbit to fake gravity, correct? This can be used on the planet's surface as well. But instead of being a circular habitat, its a parabolic habitat. The centrifugal force vector and the gravitational force vector add together. If the habitat is upside-down, the centrifugal force vector and the gravity vector cancel each other out. So to get 1G, the upside-down habitat needs to spin fast enough to generate 3G.
answered 7 hours ago
Ryan_L
3,568722
You've certainly heard of using rotating habitats in orbit to fake gravity, correct? This can be used on the planet's surface as well. But instead of being a circular habitat, its a parabolic habitat. The centrifugal force vector and the gravitational force vector add together. If the habitat is upside-down, the centrifugal force vector and the gravity vector cancel each other out. So to get 1G, the upside-down habitat needs to spin fast enough to generate 3G.
answered 7 hours ago
Ryan_L
3,568722
answered 7 hours ago
Ryan_L
3,568722
answered 7 hours ago
Ryan_L
3,568722
answered 7 hours ago
Ryan_L
3,568722
3,568722
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
add a comment |Â
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
1
1
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
"If the habitat is upside-down" - it's more like "When"
– Alexander
7 hours ago
add a comment |Â
up vote
0
down vote
On earth, at altitudes of ~1600 mi/ 2600 km 1/2 gravity is achieved. at this altitude medium earth orbits are possible.
Well shielded habitats would allow a comfortable resting environment, while any necessary on-planet industry could be facilitated with robots and human prosthesetics.
Perhaps a hardy sub-population wants to make a go of it on-surface at 2G, as well.
Changing the planetary gravity isn't worth the trouble, unless you have a plethora of handwavium.
answered 3 hours ago
theRiley
2828
add a comment |Â
up vote
0
down vote
On earth, at altitudes of ~1600 mi/ 2600 km 1/2 gravity is achieved. at this altitude medium earth orbits are possible.
Well shielded habitats would allow a comfortable resting environment, while any necessary on-planet industry could be facilitated with robots and human prosthesetics.
Perhaps a hardy sub-population wants to make a go of it on-surface at 2G, as well.
Changing the planetary gravity isn't worth the trouble, unless you have a plethora of handwavium.
answered 3 hours ago
theRiley
2828
add a comment |Â
up vote
0
down vote
up vote
0
down vote
On earth, at altitudes of ~1600 mi/ 2600 km 1/2 gravity is achieved. at this altitude medium earth orbits are possible.
Well shielded habitats would allow a comfortable resting environment, while any necessary on-planet industry could be facilitated with robots and human prosthesetics.
Perhaps a hardy sub-population wants to make a go of it on-surface at 2G, as well.
Changing the planetary gravity isn't worth the trouble, unless you have a plethora of handwavium.
answered 3 hours ago
theRiley
2828
On earth, at altitudes of ~1600 mi/ 2600 km 1/2 gravity is achieved. at this altitude medium earth orbits are possible.
Well shielded habitats would allow a comfortable resting environment, while any necessary on-planet industry could be facilitated with robots and human prosthesetics.
Perhaps a hardy sub-population wants to make a go of it on-surface at 2G, as well.
Changing the planetary gravity isn't worth the trouble, unless you have a plethora of handwavium.
answered 3 hours ago
theRiley
2828
answered 3 hours ago
theRiley
2828
answered 3 hours ago
theRiley
2828
answered 3 hours ago
theRiley
2828
2828
add a comment |Â
add a comment |Â
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What tech level? Current tech, near-future, magitech?
– Rob Watts
7 hours ago
@Rob Watts: Near future
– Aaron
7 hours ago
What is the radius of the planet - you need to know this to work out how the inverse square law applies to gravity reduction with altitude. Then you put the houses on big stilts. ;)
– Duckisaduckisaduck
7 hours ago
1
Not scientifically - what you essentially asking is antigravity.
– Alexander
7 hours ago
@Alexander: Whenever I use google, what comes up is just no gravity or more gravity.
– Aaron
7 hours ago