This is from Wikipediaformatting link
> Using the density and tensile strength of steel, and assuming
> a diameter of 1 cm at ground level, yields a diameter of several
> hundred kilometers at geostationary orbit height, showing that
> steel, and indeed most materials used in present day engineering,
> are unsuitable for building a space elevator.
I don't know enought to correct it, but it seems awfully Earth-centric. Natural perhaps but still...
Also, this statement caught my untrained eye:
Chemical energy storage (batteries, fuel cells or internal combustion engines) will not work- hydrogen/Oxygen is the chemical fuel with the best energy/mass ratio, but will not lift its own weight all the way to GEO.
rick jones