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Space Elevator Conference Prompts Lofty Questions

Posted by timothy on from the put-the-new-toys-on-the-credit-card dept.

itwbennett writes "Even the most ardent enthusiasts gathered at the annual Space Elevator Conference on Friday don't expect it to be built anytime soon, but that doesn't stop them from dreaming, planning, and trying to solve some of the more vexing problems. One of the trickiest questions is who's going to pay for the operational costs when an elevator is eventually built. 'It's been nine years we've been looking for someone' to study that, said Bryan Laubscher, one of the leading space elevator enthusiasts and principle at Odysseus Technologies, a company working on high-strength materials."

3 of 212 comments (clear)

  1. Please Mod Parent Up by Anonymous Coward · · Score: 3, Interesting

    Launch Loops are indeed far more interesting and practical. Can anyone here explain why space elevators seem to be the more popular idea among the two?

    1. Re:Please Mod Parent Up by Rei · · Score: 4, Interesting

      A couple hundred miles of maglev track versus tens of thousands of miles of unobtanium cable exposed to micrometeorites, space debris, undamped oscillations, etc. Hmm, which is more realistic...

      And I have no clue what you mean by "80 mile high bridge", except to assume that you've grossly understood how a Lofstrom loop works.

      The key issues are:

      1) A Lofstrom loop requires no unobtanium. It may well be *physically impossible* to create the material needed for a space elevator on Earth, let alone economically practical. After all, the strongest *invididual SWNTs* measured thusfar were barely over 60GPa at the density of graphite, when you need a *bulk cable* that's ideally over 100GPa at graphite densities, preferably over 120.

      2) A Lofstrom loop transmits power (the primary lift cost from both systems) at about 50% efficiency. A space elevator beams power at a couple percent efficiency. Hence a Lofstrom loop costs an order of magnitude less to operate.

      So we're back to the start. Why a space elevator, apart from the fact that everyone knows of it through sci-fi? Wait, I think I answered my own question.

      --
      Hey, guys, I'm just pleased as punch to report that it's a fleet of a hundred Vogon Battle Destroyers!
  2. Substantial Progress being made by mbone · · Score: 4, Interesting

    One of the interesting things about this conference (which I attended) is that nanoscience researchers on Friday reported substantial improvements in the ability to make carbon nanotubes. They can now "grow" 1 cm nanotube mats, which can be spun into fibers. This is a substantial improvement from even 1 year ago.

    I still think that a terrestrial space elevator is a decade out, but this year has convinced me that it is coming much faster than a lot of people think.