• Mardoniush [she/her]
    ·
    3 years ago

    That's just a space elevator. Unfortunately, a 32,000km tether requires semi-unobtainium (A monomolecular carbon nanotube just about does the job, but also it needs to be a giant braid of single 32,000km molecules with no defects)

    • sooper_dooper_roofer [none/use name]
      ·
      edit-2
      3 years ago

      it's not the same thing as a space elevator though, because it wouldn't need to move any loads. Just passively diffuse out gas. I'm sure there are plenty of reasons why it wouldn't work yes

      why would it need to be 32000 km? only 400 km would be enough to get the co2 to directly enter outer space

      The main issue I see is the weight of the tubing, it would need to be anchored to a satellite with some kind of energy reserve that allows it to indefinitely support the tube's weight

      • Segorinder [any]
        ·
        3 years ago

        Light particles like helium can escape from the edge of the atmosphere. CO2 is ~11 times heavier, so you have to pump it well above the atmosphere for its orbit to have a chance of carrying it away, or else it will just fall right back down. It's probably not that difficult to maintain the pressure on the ground to keep it flowing, but the problem is you now need 1000's of km of a rigid pressure vessel, instead of a thin film or something.

      • Mardoniush [she/her]
        ·
        edit-2
        3 years ago

        Gas has mass. The density differential of gases heavier than oxygen can't overcome gravity. You have to lift it, so you have an elevator.

        It actually needs to be longer than 32000km if you want it to be geostationary because it needs a counterweight so the tension on the cable is equal at GEO. Yes you can vent the gas at LEO (though it will eventually come back down in a decade or so at that altitude)