I am aware that there is a concept called "space elevator" that would be a much cheaper and more efficient option of reaching space with a construction (even though we don't have the technology for that).

However, I am interested in knowing the absurd proportions and costs necessary to build a building that would reach space. Including the difficulties they would encounter, such as incredibly fast winds and an absence of oxygen at certain times.

I know that such a construction would not be feasible on earth, but I am still interested in the absurd epicness of building something like this.

Even if the first 300 floors are just a giant base of pure concrete and steel, even if the ground sinks by its weight, I wanna know.

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    $\begingroup$ Your thirst for knowledge is commendable, your thirst for the inherent drama of such a story I share. You've asked us a question, told us it's impossible to answer - since we don't write your story for you, it's difficult to see how it's on topic. Thing is, it could be feasible with materials a couple of (maybe 3) orders of magnitude stronger than today. What are you trying to solve here? (I mean in terms of worldbuilding problems) $\endgroup$ Feb 8, 2021 at 23:24
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    $\begingroup$ Even the Empire State Building stuck a big "dirigible mooring" on top to pad their height numbers. Do the floors need to be accessible/useable? Plumbing, power and (yes) elevators would vastly complicate matters. Do you have a minimum diameter? $\endgroup$
    – DWKraus
    Feb 8, 2021 at 23:45
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    $\begingroup$ No material available today has anywhere near the required strength. Sorry. (A space elevator is conceivable, because the tether is stressed in tension, and some materials, such as carbon nanotubes, approach the required strength in tension. But a building would be stressed in compression, and the best materials are many times too feeble in compression. As an aide-memoire: Mountains cannot possibly be taller than 10 km or so because if they were taller the rocks at the bottom would flow away like a fluid.) $\endgroup$
    – AlexP
    Feb 8, 2021 at 23:51
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    $\begingroup$ @Dragongeek Part of the issue here, is how much mass in a given area before the Earth's crust not just sinks, but breaks, and the mass disappears into the mantle. (Separate question) $\endgroup$ Feb 9, 2021 at 1:00
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    $\begingroup$ Question for the closers: given the discussion on Meta, how do you view this query as a duplicate? The other question asks specifically about the Star Wars universe (technically off topic here, as it is a commercial property); this question asks, presumably, about the OP's own fictional world. I'd argue that the OP did not write this question as well as could be, but I'm not convinced that it's a duplicate either. $\endgroup$
    – elemtilas
    Feb 13, 2021 at 23:18

1 Answer 1


It can be done, but involving active systems on a scale far beyond anything humanity has ever done, cost estimates are not possible.

AlexP is right that there's nothing remotely strong enough to build it out of. No passive structure can reach anywhere near space.

However, active structures do not have this limit. The simplest approach is to build your tower around an incredibly powerful space fountain. The base of your tower is bunch of linear motors that throw magnets up very, very fast. Thus must be done in an evacuated tunnel or they will be vaporized.

Once you have this base you build the top of the building. It has huge magnets that catch the rising magnets and turn them around, throwing them back down. Newton's Third Law--the building is pushed up. The base does the same thing, throwing them back up. The stream of magnets supports the building, but note that they need no strength to do this. If the magnets are superconducting this uses no power. (You still will need power for the control systems and you will use a lot of power boosting them at the start.)

Once you have built this you use the magnets to lift the building top on it's magnets. Now you build the next to top floor. It does not turn the magnets around, it just extracts energy from the magnets heading up and uses that energy to push the magnets going down. Once again, superconductors. When it's ready you turn up the power on the base so the magnet streams can support the new floor also.

Repeat again and again until your building reaches space.

Your engineering must be very, very good--while you certainly have redundancy build in but if too many systems are down your tower collapses. You had also better keep the magnets in their paths, the results of a magnet touching their channels will be dramatic and once a track is breached air will get in and vaporize every magnet in the channel. Goodbye tower.

  • $\begingroup$ @Tantalus'touch. Why not? While it's a SciFi idea it's only a matter of scale, it doesn't require any technology we don't already have. $\endgroup$ Feb 9, 2021 at 4:01
  • $\begingroup$ I'd not looked into it in depth, as now I look, it seems (according to the very cursory description in Wikipedia) we might be able to do it with what we have now. OK, it works as an answer, you're right. +1 $\endgroup$ Feb 9, 2021 at 4:07

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