Typically when you see a diagram of a space elevator, you see something like the image at the top of this article: Earth, geosynchronous orbit, and a space elevator extending just a little bit beyond it. A space elevator is like a sling for space craft and cargo. Earth is about the worst place to build a space elevator, which is why we need nanotubes to do it. To be clear, the space elevator described above is not crazy science fiction; it’s science fact that just doesn’t happen to exist right now. The total energy the space craft needs is , and since , the space elevator covers of the total energy cost.