Supra-polar "continents" on Earth

karov · 2013-10-07 13:52:05

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based on the ref.s above:

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Not exactly rings but archs. Touching the ground at equator - thus linking Earth surface "horizontal" ground transport modes like railways or vac-tubes ( a-la- http://et3.com/ ) directly with the new suspended over the poles new "continents".

Height 1 Earth radius over the surface, or 1 Earth diameter from Earth's centre. Thus, surface gravity on the suspended "plates" will be 1/4 gees. The limits are: go higher = lower surface gees, go lower - you start shading portions of the Earth's surface.

"Plates" diameter - say 10 000km, area - 80 000 000 km2 , each. Supercontinents indeed. http://en.wikipedia.org/wiki/Afro-Eurasia , multiplied by 2.

I call them "plates" because for most of their area they are concentric to the Earth's surface bellow, except for the rim areas where terrain ( very ) gradually goes up until it is hundreds of km higher then the tropopause is at 0.25 gees. Thus, providing "walking" access to vacuum.

Lets call them Borea and Anaborea, because Artica-Antarctica doublet is occupied.

Illumination? Mirror statite systems , suspended by the light they redirect towards the plate at ~1mln. km hight on the Hill radius borderline. Ref.:

Terraformer · 2013-10-07 14:21:56

How are they any better than spending the resources on a few large space colonies?

RobertDyck · 2013-10-07 20:47:35

First, when I click on your link, I get redirected to a site to purchase the URL. None of the links work.

But I have an even simpler idea: just let global warming happen, and settle the arctic/antarctic. It will flood some tropical islands, and some coastal cities will require dikes like Holland. America calls them "levees". But global warming is happening, like it or not. That means Canada's arctic and the antarctic will become habitable. Sure, the Inuit of Canada's arctic may claim it was habitable before, but there wasn't much population or industry. Again, what we want doesn't matter, global warming is happening. And in the time of the dinosaurs, antacrica had a taiga forest. That means forest with permafrost, like Alaska. Trees are short and stunted, and leaning at odd angles due to days when the permafrost melts. The arctic/antarctic appears to do this during every interglacial period, and is happening again. We can't stop it. So why not just go with it?

karov · 2013-10-09 12:09:47

RobertDyck wrote:

First, when I click on your link, I get redirected to a site to purchase the URL. None of the links work.
But I have an even simpler idea: just let global warming happen, and settle the arctic/antarctic. It will flood some tropical islands, and some coastal cities will require dikes like Holland. America calls them "levees". But global warming is happening, like it or not. That means Canada's arctic and the antarctic will become habitable. Sure, the Inuit of Canada's arctic may claim it was habitable before, but there wasn't much population or industry. Again, what we want doesn't matter, global warming is happening. And in the time of the dinosaurs, antacrica had a taiga forest. That means forest with permafrost, like Alaska. Trees are short and stunted, and leaning at odd angles due to days when the permafrost melts. The arctic/antarctic appears to do this during every interglacial period, and is happening again. We can't stop it. So why not just go with it?

RobertDyck,

or both - two floors.

karov · 2013-10-12 04:35:54

Because of the curvature the area of these "supra-polar caps" would be rather 100-ish mln. sq.km. or comparable with the total land area on Earth, each. Effectivelly tripling of the land area of the planet.

Given Birch's estimates about the geosphere ( = litosphere+hydrosphere ) + atmosphere mass of roughly 40-50 tonnes per sq.m. incl. the toposphere, and rounded up - this calculates to roughly 10exp19 kg for the supra-polar caps + dynamic compression members support system mass.

Between the mass of:

5.6×10exp18 kg Hyperion, a moon of Saturn.

and

3×10exp19 kg 3 Juno, one of the larger asteroids in the asteroid belt.

OR

roughly 1/10000th of the mass of the Earth's Moon. ( just a slug byproduct of Lunar terraforming ).

Descending 10ex19-ish kilograms of mass from Moon to Earth will provide us with ALL the energy for construction, simultaneously with the materials.

OF COURSE, nobody incl. me will vote for such brutal superstructure of our home planet, but similar techs could be ( i.e. SHALL ) be implemented on numerous other worlds.

Last edited by karov (2013-10-12 04:47:44)

JoshNH4H · 2013-10-13 17:35:48

Why not do it with materials from Earth?

JoshNH4H · 2013-10-13 21:29:40

Also, do you have any idea of what kind of materials would be needed to construct the supports? A high shear strength (which means a high tensile strength, assuming you have an isotropic material) would be needed. Any estimates for how heavy the supracontinents would be?

karov · 2013-10-14 11:38:07

JoshNH4H wrote:

(1) Why not do it with materials from Earth? (2) Also, do you have any idea of what kind of materials would be needed to construct the supports? (3) A high shear strength (which means a high tensile strength, assuming you have an isotropic material) would be needed. (4) Any estimates for how heavy the supracontinents would be?

(1) - of course. Such structure could be built bottom-to-top. http://en.wikipedia.org/wiki/Launch_loop Indeed the lift up of mass, would serve for decreasing of the overall ocean level on Earth thus opening up dozens of millions of new sq.m. of fresh land.

(2) - absolutely, nowadays, mundane, plain materials.

(3) - http://www.orionsarm.com/fm_store/Paul%20Birch's%20Page.htm , and more precisely - http://www.orionsarm.com/fm_store/Dynam … embers.pdf

(4) - if 40-50 tonnes per sq.m. about 10exp19 kg both.

Last edited by karov (2013-10-14 11:42:09)

JoshNH4H · 2013-10-14 23:58:03

I've never really been a fan of dynamic compression members: They require constant energy input, or else they fail immediately. It's very poor design. Also, 50 kg/m^2 seems unreasonably small for actual livable area. I'd look at more like 250 kg/m^2. Assuming a mass of 5e19 kg, and a tensile strength of 500 MPa (implying a shear strength of 250 MPa) an area of 2e12 m^2 of steel would be needed to hold this up. That's 2,000,000 km^2, or a rectangle 1,000 km by 2,000 km. Quadrupling for margin and to account for the fact that additional structures will be needed to account for bucking, that's 8e12 m^2. Assuming that the supports are 15,000 km long, they will use 2e23 kg, outmassing your actual continents by a factor of 20,000. Because my analysis neglected their mass, it will actually be even worse than this.

I can see why you'd propose dynamic support members, but those have their own issues

karov · 2013-10-17 04:14:05

http://www.orionsarm.com/im_store/med_d … member.jpg

I've never really been a fan of dynamic compression members: They require constant energy input, or else they fail immediately. It's very poor design.

No. They won't fall immediatelly. Energy input is (design-dependent) infinitesimal. Even using existing electromagnetic coupling techniques.
The whole system is a reservoir of energy, the same way is a static support structure.
Kinetic structure are not more prone to catastrophic failures then static ones.
Also kinetic are smart, static are un-controllable.
Normal living environment is a system of kinetic balansed ones. Even tectonics are buoyancy system.
In this universe there ain't better designs then kinetic ones...

Also, 50 kg/m^2 seems unreasonably small for actual livable area.

50 THOUSAND kg/m2 = 50 metric tonnes per sq.m. of living area. Equal to dozens of meters of floor "underfeet" , "foamy" core, stiff surface sculptured terrain ... ... shallow up to 10m average water basins... adaptive terrain suspension...

I'd look at more like 250 kg/m^2. Assuming a mass of 5e19 kg, and a tensile strength of 500 MPa (implying a shear strength of 250 MPa) an area of 2e12 m^2 of steel would be needed to hold this up. That's 2,000,000 km^2, or a rectangle 1,000 km by 2,000 km. Quadrupling for margin and to account for the fact that additional structures will be needed to account for bucking, that's 8e12 m^2. Assuming that the supports are 15,000 km long, they will use 2e23 kg, outmassing your actual continents by a factor of 20,000. Because my analysis neglected their mass, it will actually be even worse than this.

Tensile strength immaterial. The supra-polar caps will distribute upward supporting pressure from the mass-streams laterally in order this to spread into reasonable amount of stress per square mile, meter, ... unit of area.

The mass-streams will be counter-directed by other such. In order to keep axial stability of the whole system. They could be round, but I deliberatelly showed tangential , equator-touching ones for providing land-bridging.

The mass invested into the mass-streams depends on the selected operational velocity.

Last edited by karov (2013-10-17 11:47:55)

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#1 2013-10-07 13:52:05

Supra-polar "continents" on Earth

#2 2013-10-07 14:21:56

Re: Supra-polar "continents" on Earth

#3 2013-10-07 20:47:35

Re: Supra-polar "continents" on Earth

#4 2013-10-09 12:09:47

Re: Supra-polar "continents" on Earth

#5 2013-10-12 04:35:54

Re: Supra-polar "continents" on Earth

#6 2013-10-13 17:35:48

Re: Supra-polar "continents" on Earth

#7 2013-10-13 21:29:40

Re: Supra-polar "continents" on Earth

#8 2013-10-14 11:38:07

Re: Supra-polar "continents" on Earth

#9 2013-10-14 23:58:03

Re: Supra-polar "continents" on Earth

#10 2013-10-17 04:14:05

Re: Supra-polar "continents" on Earth

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