• seaQueue@lemmy.world
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    1 year ago

    Can we just get on with engineering a space elevator already? We’re going to want one if we’re serious about exploiting resources off planet.

    • Pons_Aelius@kbin.social
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      1 year ago

      You might as well ask: “Can we just get on with engineering an FTL drive?” as it is about as far beyond our capabilities as a space elevator is.

      • Overspark@feddit.nl
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        1 year ago

        It really isn’t. We know it’s possible, we roughly know how to build one, it’s only our material science that isn’t there yet. But there are promising leads in that direction and with the right investments that problem looks solvable.

        https://youtu.be/lldv_u4R6BU?si=65llxa5uHygOlT3K

        With FTL our current science is saying that it’s probably impossible and will never happen. We might be wrong about that, but if we are it’s not going to be cracked anytime soon.

        • Pons_Aelius@kbin.social
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          1 year ago

          Yes, we have the theory of what is required to build one but every material we have (including graphene and carbon nanotubes) is about 2-3 orders of magnitude below the tensile strength that is required for a space elevator on earth. Add in the fact that the longest graphene and carbon nanotube we can currently produce is in the mm range and we need it to be ~50,000 km and perfect at the atomic level we would be at best decades away from production if they could be used.

          Ironically the best place for us to begin is in space.

          Building space elevator on the moon is much, much easier (1/6 G and no atmosphere) and Mars is also a much easier proposition than on earth (1/3 G and 1/1000th the atmospheric pressure).

          I fully expect that if humans ever build space elevators the first one will not be on earth.

      • grahamja@reddthat.com
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        1 year ago

        I also am under the assumption that no material exists that could be stacked tall enough to build a space elevator.

        • seaQueue@lemmy.world
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          1 year ago

          You’d want tensile strength rather than compressive. The trick is to anchor a counterweight out beyond your target distance and let it pull the weight of the cable up rather than building a tower. Think of swinging a ball on a string rather than building a skyscraper. Assuming a sufficiently sized counterweight you can support the weight of the anchoring cable plus whatever else you want to hang off of it (space dock, elevator terminus, etc.)

        • Heggico@lemmy.world
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          1 year ago

          If you build it tall enough, centrifugal force will start pulling on it. Building it that way though… But yeah. Doubt the right material exist atm.

        • crystalmerchant@lemmy.world
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          1 year ago

          stacked tall enough…? The space elevator concept is a geostationary node orbiting earth directly above a fixed point, with cables running between them. Not a gigantic skyscraper up into the sky. What am I missing?

          • Cosmicomical@kbin.social
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            1 year ago

            You probably haven’t read 3001: the final odissey, in any case i think most ideas of space elevators are not like a lift, they are more like skyscrapers indeed.
            Edit: i might be very wrong though, i’m not up to date on this

      • seaQueue@lemmy.world
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        1 year ago

        I’m thinking we’re going to want either really big spiders or a whole lot of goats now that we’ve spliced the spider silk genes into goats milk.

    • HubertManne@kbin.social
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      1 year ago

      I don’t know why we have not been working out the kinks on the moon given how achievable its been for that for years.