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Space Elevators: Low Cost Ticket to GEO?

Posted by michael on from the seven-days-of-muzak-and-seven-more-to-go dept.

Crocuta writes "The current issue of Science News features a cover story that discusses the current developments in space elevator technology. NASA has been working on such devices for many years, but private companies such as Highlift Systems are now jumping on the space elevator bandwagon, no doubt seeing the huge potential profit in a low cost per pound delivery system. PhysicsWeb has a somewhat older, but much more technical article on the formation and structure of the carbon nanotubes that form the basis of the proposed tether cables. With a development like this, we could shoot entire boy bands into space and make the world a better place."

6 of 426 comments (clear)

  1. More info by Truckle · · Score: 4, Informative

    Here are some more links to info on our very own Slashdot:

    Here
    Here..
    Here..
    and Here

  2. Really good NASA article by Tidan · · Score: 5, Informative

    Here's a nice sized (15MB) report done by NASA. They talk about all sorts of problems that need to be worked out to make get this project off the ground http://www.niac.usra.edu/files/studies/final_repor t/pdf/472Edwards.pdf

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  3. Short term option by alwayslurking · · Score: 4, Informative

    You don't need to tether the end, you can still get some very healthy benefits with a partial elevator. Deals with a lot of the security issues too. Cargo craft only need to fly to the low end and ride the rotation to the top where they can slingshot off. Using the Earth's magnetic field and solar power means it's self-stabilising too. More detail and better writing at; Free David Brin Short Story

  4. Re:another use for it... by Soft · · Score: 4, Informative
    The "slingshot effect" is only useful for trajectory changes. It allows one to save fuel when changing directions. Due to conservation of energy, when you approach a planet and slingshot away from it, you end up with the same velocity on the way out as the way in. You will accelerate as you approach a planet, but you will decelerate the same amount on the way out.

    All true, but you missed two points:

    • in a slingshot maneuver you cannot, indeed, gain velocity relative the planet you approach; you can (and space probes do) gain velocity relative to the Sun, since said planet is moving with respect to the latter;
    • the original poster, I think, did not have a gravitational slingshot in mind, but the effect you would get if the top of the elevator were above GEO, you could launch objects that way.
  5. Re:another use for it... by ENOENT · · Score: 5, Informative

    BZZT!!! No, you're forgetting that the planet has its own velocity, which a spacecraft can steal. When a spacecraft slinshots around a planet, its velocity on the way out is the same as its velocity on the way in, but this the the velocity RELATIVE TO THE PLANET. If the spacecraft approaches the planet head-on, and does a 180 degree slingshot around the planet, then (ideally) its final velocity RELATIVE TO THE SUN is equivalent to its initial velocity plus two times the planet's orbital velocity. Energy is conserved, because the energy gained by the spacecraft is stolen from the planet.

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  6. Highlift Systems FAQ by TheOnlyCoolTim · · Score: 5, Informative

    Will the wire generate power?

    Yes, but only in the milliwatts.

    Tim

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