New Mars Forums

Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Saturn a shell world

After mining hydrogen from Saturn for some time, we might try building a nested sphere around Saturn, and creating a World with 93 times the area of Earth.

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,863

Re: Saturn a shell world

Saturn is such a distant world that we can only achieve such goals with the help of nuclear power as the amount of solar is to low....
As for Venus we need to be able to make it a best we can from insitu sources either in part or in full as the spheres are built.

Antius

Member

From: Cumbria, UK

Registered: 2007-05-22

Posts: 1,003

Re: Saturn a shell world

How are you going to build a shell around a diffuse ball of hydrogen gas several times the Earth's diameter?  Where would you get the materials from?  Why would you even start?

Put yourself in the position of a governor sitting within a city on Titan a few centuries hence.  Why would building a shell around Saturn be an attractive proposition to you?  Ideas like this stand a much better chance if you can think of ways that people could start small, earn money as they go and gradually build up to the end result.  Maybe we start with helium 3 mines in the atmosphere held aloft with fusion powered hot balloons.  Gradually settlements expand as demand expands until ultimately it makes sense to join them into a shell covering the planet.

The reality of all huge human constructions like cities on Earth, is that they are never simply built as single projects.  They start as tiny villages and grow incrementally into the vast metropolises that we see today.  What made your idea of ice castles on Titan so cool, was that it provided a workable technology that would allow small groups of human beings to use local materials at low resource cost to create habitable spaces that could ultimately transform the planet.  But they dont start that way, they start insignificant and gradually grow with time as population pressure provides an incentive to grow and money allows it.  Ultimately your ice shells cover most of the planet.  Always try to think of concepts that can grow organically, starting small and using strictly local resources  and earning money by selling something that other people need and you are generally onto a winner.

Venus colonisation is less likely than Mars colonisation precisely because we cannot start small and incrementally.  We would need planetary engineering before we could even start colonising Venus.  And it isnt clear why people would decide to go there and make the initial steps of colonisation in the first place.  Is there something on Venus that we could easily export at profit that justifies the expense of colonisation?  I cannot think of anything that you wouldnt find elsewhere.  Anything you do export needs to be valuable as the cost of transporting it anywhere else is high.  Maybe we could build colonies in high Venus orbit to harvest nitrogen mined from the atmosphere and sell it as buffer gas to O'Neill colonies?  Mars colonisation doesnt have the issue of needing planetary engineering just to begin, but there is the problem of why we would start in the first place when the cost of mounting a simple exploratory mission runs into tens of billions of dollars.

Asteroids have clear economic pathways that would allow colonisation to begin and we can begin terraforming a world like Eros simply by hollowing it out by mining and leaving a breathable atmosphere in the hollow that is left behind.  But it is doubtful at present that the value of metal exports could finance the cost of establishing an initial outpost.  But the key to making it happen is to establish a foot in the door strategy that starts small and gradually grows bigger as you earn more money.  Any other project in the future will have to work the same way, wherever and whatever it is.  By thinking this way, your ideas move at least to the status of science fiction as there are plausible ways to make them happen.  Otherwise it is all just pie in the sky.

Last edited by Antius (2016-05-01 04:57:10)

Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Re: Saturn a shell world

How are you going to build a shell around a diffuse ball of hydrogen gas several times the Earth's diameter?  Where would you get the materials from?  Why would you even start?

Atmospheric makeup Saturn is made up predominantly of hydrogen, which it captured in the early stages of its formation. Most of the remaining composition is helium. Other elements, such as methane and ammonia, are found in small doses. Nitrogen and oxygen also mix within the atmosphere. - See more at: http://www.space.com/18475-saturn-s-atm … ZIJj9.dpuf

Composition

by volume:

≈ 96% hydrogen (H2)
≈ 3% helium (He)
≈ 0.4% methane (CH4)
≈ 0.01% ammonia (NH3)
≈ 0.01% hydrogen deuteride (HD)
0.0007% ethane (C2H6)
Ices: ammonia (NH3)
water (H2O)
ammonium hydrosulfide (NH4SH)

I see lots of stuff we could make solid material out of right out of the atmosphere. Plastics are made out of hydrogen, oxygen, nitrogen, and carbon, and that stuff is right in Saturn's atmosphere.
Methane contains carbon, from which we can make diamond and other plastics.

Put yourself in the position of a governor sitting within a city on Titan a few centuries hence.  Why would building a shell around Saturn be an attractive proposition to you?  Ideas like this stand a much better chance if you can think of ways that people could start small, earn money as they go and gradually build up to the end result.  Maybe we start with helium 3 mines in the atmosphere held aloft with fusion powered hot balloons.  Gradually settlements expand as demand expands until ultimately it makes sense to join them into a shell covering the planet.

The reality of all huge human constructions like cities on Earth, is that they are never simply built as single projects.  They start as tiny villages and grow incrementally into the vast metropolises that we see today.  What made your idea of ice castles on Titan so cool, was that it provided a workable technology that would allow small groups of human beings to use local materials at low resource cost to create habitable spaces that could ultimately transform the planet.  But they dont start that way, they start insignificant and gradually grow with time as population pressure provides an incentive to grow and money allows it.  Ultimately your ice shells cover most of the planet.  Always try to think of concepts that can grow organically, starting small and using strictly local resources  and earning money by selling something that other people need and you are generally onto a winner.

Venus colonisation is less likely than Mars colonisation precisely because we cannot start small and incrementally.  We would need planetary engineering before we could even start colonising Venus.  And it isnt clear why people would decide to go there and make the initial steps of colonisation in the first place.  Is there something on Venus that we could easily export at profit that justifies the expense of colonisation?  I cannot think of anything that you wouldnt find elsewhere.  Anything you do export needs to be valuable as the cost of transporting it anywhere else is high.  Maybe we could build colonies in high Venus orbit to harvest nitrogen mined from the atmosphere and sell it as buffer gas to O'Neill colonies?  Mars colonisation doesnt have the issue of needing planetary engineering just to begin, but there is the problem of why we would start in the first place when the cost of mounting a simple exploratory mission runs into tens of billions of dollars.

Asteroids have clear economic pathways that would allow colonisation to begin and we can begin terraforming a world like Eros simply by hollowing it out by mining and leaving a breathable atmosphere in the hollow that is left behind.  But it is doubtful at present that the value of metal exports could finance the cost of establishing an initial outpost.  But the key to making it happen is to establish a foot in the door strategy that starts small and gradually grows bigger as you earn more money.  Any other project in the future will have to work the same way, wherever and whatever it is.  By thinking this way, your ideas move at least to the status of science fiction as there are plausible ways to make them happen.  Otherwise it is all just pie in the sky.

A Saturn shell would require nanotech, basically the premise is, if we had nanotechnology, what would we want to build. The nanotech molecules are universal assemblers, they build copies of themselves and other things. so the way we would build it would be to seed the clouds of Saturn with Universal assemblers, the first thing they would build would be balloons. One way to stay aloft would be to have pure hydrogen balloons, and make them big enough so that the volume of hydrogen contained within weighs less than the surrounding atmosphere which is 25% helium, and thus denser, Also if the Balloon membrane is black, it would absorb the feeble sunlight, and heat the interior gases a little bit.

The balloons would divide and multiply like cells, they would also stick together, to form a layer around the planet. When the planet is completely surrounded, the nano-assemblers would begin building fusion reactors. The fusion reactors would provide power to heat the gases within the balloons, also a membrane would be grown on top of the Balloon layer. The outer membrane would have some holes it is with fans to push the gases underneath to support the weight of the membrane, the balloons would be disassembled as they would no longer be needed. At this point, construction of the centrifuge pathways would be constructed within the membrane, at this point supported by internal pressure within Saturn's atmosphere. Once the crisscrossing pathway network is complete, then diamond belts would be accelerated to super-orbital velocity within evacuated tubes and supported with magnetic fields.  Once all the belts are going, the nanotech again works on the membrane hardening it to form a rigid shell, since the shell is now supported by the centrifuge belts, a second layer of the membrane is grown and selected gases are pumped in between the two layers, the nitrogen is obtained from ammonia (NH3), Oxygen is obtained from water (H2O) and water is pumped in as well. Carbon dioxide is obtained from Methane (CH4) you burn the methane with some of the freed up oxygen producing carbon dioxide and water vapor. The gases are adjusted to produce a breathable atmosphere for humans, animals, and plant life. The nanotechnology just goes on producing this giant world. Saturn has the surface area of 83 Earths, the gravity is already about right, and it is built within the atmosphere, you can use the atmosphere itself to stabilize the shell, keep it centered on the planet, and holes through the two layers with pipes to confine the gas passing through allows the atmosphere to expand as it is heated by the terraforming process.

Last edited by Tom Kalbfus (2016-05-01 09:31:54)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,863

Re: Saturn a shell world

I hope you do not mind my splitting up the shell world topic....

A titan shell world used as a first step towards Saturn sounds like a plan to harness these gas giants...

1

Self-replicating nanites.  That is one scary thought - rather like the Stargate replicators.  With truly self replicating machines you really would have infinite power.  But what happens if they get away from you? I guess it is doable with tech like that, but your shell machines would need to replicate using just a handfull of elements.

Well its hard to terraform any planet without something that self-replicates, whether it be plants, microbes, or nanites. Saturn is such an alien planet, that I think we will have to create our own life forms that can survive and replicate in that environment. Some people have limited imagination of what can be done with them, such as wiping out the human race. I think the first wave will be the onset of strong AI, machines that are equal to or superior to human intelligence, when that happens we'll have to give them tasks that are worthy of them, like terraform planets. I think we can terraform the other gas giants as well. Jupiter would make an area equal to 318 Earths under 1 Earth gravity, Saturn has 95 Earths worth of Surface area. Uranus has 14, Neptune 17. As you might have guessed the 1-G sphere around each planet has a surface area proportional to the planet's mass in Earth masses. With Jupiter you follow the same procedure as with Saturn, except when you harden the shell, and spin up the belts, the sphere and belts stretch and expand to 1.59 time its current radius to put its surface within Jupiter's 1-G sphere. Some tethers will hang down into Jupiter's atmosphere, and belt will run down the tether and absorb hydrogen, the hydrogen is then transported up the tether along the belt and then fed into one of many thermonuclear reactors on the top shell, and this powers the sunlight on the inner habitable surface.

I think creating nanotech and AIs would be similar to humans making first contact with an alien civilization of superior intelligence and technology, only in this case we get to create the aliens that contact us, so hopefully we create good ones that don't want to wipe us out! I'd say use them to build shells around planets that we can inhabit, then get them out of our way, so we can colonize those planets.

Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Re: Saturn a shell world

I hope you do not mind my splitting up the shell world topic....

A titan shell world used as a first step towards Saturn sounds like a plan to harness these gas giants...

With Titan, you would need only the top shell to hold in the atmosphere after you warmed it up, as its crust consists or water ice, it would become an ocean world. the top would have fusion reactors to power the artificial daylight just as in Saturn, we would give Titan a 24 hour day with a 365 day seasonal cycle, and then we would have to work on something to stand on rather than having to tread water all the time. Titan has 1/7th of Earth's gravity, the troposphere of the Moon would therefore be 56 km high or 35 miles rather than 8 km or 5 miles as it is on Earth. I think on the ceiling, we might want to project the illusion of Titan rotating with an Earth like 24 hour period that is on the underside of the shell, we would project a real time image of Saturn rising and setting, even though in actuality Saturn stays in a fixed position in Titan's sky from any given location. And on the outer surface of the shell, we would project an image of Titan rotating with a 24 hour period and of course changing its axis of rotation to match a 365 day Earthlike seasonal cycle. This seems to be much easier than doing tricks with giant space mirrors at this distance from the Sun. For one thing, it would be hard to do with Titan since it orbits Saturn. Its much easier just to create artificial sunshine, and not worry about the orbital mechanics of placing giant mirrors in space. On terraformed Titan, flying would be very easy due to its thick native atmosphere and low gravity. One might entertain the thought of just living on flying platforms above the endless global ocean. you could mount a building or even a city on a giant quad-copter such as those used by drones to hover.

Imagine this were a city on Titan, hovering above giant slowly undulating waves in a low gravity endless ocean. This way at least you avoid rocking and getting people seasick!