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Comment by WtfRuSerious | Hacker News Reader

What about at the poles?

Seems like that would negate the lateral problems, but maybe I'm just introducing a twisting one instead...?

Then you have an enormously large tower held up by nothing but its own strength instead of being naturally pulled into space. Also takes additional delta-v to get satteliges into common orbits post release.

This is arguably more doable than cables. I've been told that it's completely possible to build steel structures several miles tall (and the main reason we don't is b/c elevators become a problem).

We can build massive steel towers (e.g. https://en.wikipedia.org/wiki/X-Seed_4000 would be 4km tall), but they would still be nowhere near space (one common definition of reaching space is https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line which is at 100km).

A space elevator would reach at least 36,000km to hit geostationary orbit ( https://en.wikipedia.org/wiki/Geostationary_orbit ). Most designs are even longer, to provide a counterweight.

No known material could support a tower that tall (towers need compressive strength; elevators need tensile strength). It would need to rely on 'active support' or 'dynamic structures', like a space fountain ( http://www.orbitalvector.com/Orbital%20Travel/Space%20Founta... )

A friend of mine who studies engineering told me that masonry has infinite compressive strength meaning, in theory, it's possible to build monumental structures out of stone.

The base needs to be large enough to support the weight, so you get less of a tower and more of a mound (like the great pyramids).

We can get to about 9km using stone by climbing Mount Everest.

I think it would be the same ∆V requirement (for geosynchronous orbital altitude). But it's not possible to have a geo orbital plane (so the subsatellite point is stationary on the Earth) that is out of the equatorial plane.

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