Moon mining gains momentum as private companies plan for a lunar economy::A number of entrepreneurial groups have shared their strategies to turn the moon into a hustle and bustle world of marketable services.

  • Aceticon@lemmy.world
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    1 year ago

    Wasn’t the Moon’s gravity low enough that you could basically use electromagnetic cannons to launch payloads from the surface all the way out of lunar orbit?

    In the absence of an athmosphere and with only 16.6% of Earth’s gravity, achieving orbit from the Moon isn’t simply “not as though” as doing so from Earth, it’s incredibly less so (maybe 100s of times, though I don’t really have the numbers so take it with a grain) - just compare the size and fuel payload of the vehicle needed to put 3 people on the Moon and those of the vehicle needed to bring them back to Earth (granted, the first vehicle had to also carry the second one, plus food, water and air for the first part of the trip).

    Being at the bottom of a 1G well and having to also overcome quite a lot of air drag to get out of it massivelly adds up to the energy needed to do so, because the whole thing is a logarithmic progression (as you need to spend fuel to haul up the fuel that’s going to be used higher up), so overcoming 6x the gravity doesn’t just mean using 6x the fuel, and that’s even before we go into the losses due to drag in the lower athmosphere.

    • FartsWithAnAccent@lemmy.world
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      1 year ago

      I don’t know anything about EM canons but between the moon having a relatively weak gravity well and being within Earth’s gravity well, I’d think any method would be much easier to use when it comes to transport to Earth

      • markr@lemmy.world
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        1 year ago

        Ok so I did a small bit of research and found optimistic estimates from groups promoting this of $800kg. You can’t just throw shit at earth, you have to put it down safely. In reality what makes sense is manufacturing stuff that you then don’t have to bring up to the moon, or to mars, or anywhere else off of earth. You build it on the moon instead.

        • FartsWithAnAccent@lemmy.world
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          1 year ago

          IDK $800/kg sounds pretty great compared getting into Earth orbit at $54,000/kg. Doing something like manufacturing and launching satellites would probably become pretty viable once it’s set up.