OT: Building O'Neill habitats on Earth?

On 7/4/05, Lucio de Souza Coelho wrote:
>
> Maybe my intuitive reasoning is wrong, but I think that the pressure
> distribution in a sphere or cylinder 10 Km across would be completely
> different in Earth's gravitational field - which is basically uniform
> close to the surface, very different from the radial "gravitational
> field" of a habitat. So I don't think that pressure alone could
> sustain the building, if that is what you are hinting.

Well, pressure halves every 6km on earth, so the pressure at the top is only
1/3 that at the bottom.

So if you run the bottom at 2 bar absolute, the top would still be 1/3 bar
above ambient, about 3 tonnes per square meter. So provided you have less
than 3 tonnes of stuff per square meter it stays up. IRC with O'Neil
cylinders I think the aluminum itself is maybe 3cm thick. That works out at
only 81 kg per square meter.

It's a surreal idea, but it seems to work.

--
-Ian Woollard

Simplicity is the ultimate sophistication - Leonardo
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