• CleoTheWizard@lemmy.world
    link
    fedilink
    English
    arrow-up
    3
    ·
    3 months ago

    Not sure what will blow your mind but here’s some fun facts I feel like people don’t commonly know:

    1. Lunar regolith isn’t shallow, in many areas the regolith is 5m deep in the highlands and in craters and other areas it can be as much as 15m deep
    2. The regolith contains agglutinates, particles of rock that have been melted together by meteor impacts. They’re basically rock glass that contributes to the high abrasion of the regolith. We don’t have much of that stuff on earth and it’s very hard to make ourselves.
    3. Due to the lack of atmosphere, much of the dust is charged statically and will cling to astronauts and machines. I knew teams working on a sort of pulsing electricity in a grid of wires to repel the dust off of panels and suits.
    • brbposting@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      2
      ·
      3 months ago

      So earth has a moon which is covered in rock. Meteors slam into it which melts that rock together into very angular (sharp) rock glass.

      Rocks on the moon don’t just pile up a little bit. They might be 15 meters deep in certain craters. Almost as helpful as quicksand for those who want to walk or drive over it.

      Some of the smallest rocks on the moon cause trouble for astronauts: statically charged dust. It sticks to people and equipment, and creative solutions (pulsingly charged wire grids) have been necessary to mitigate it.

      Oh yeah - that’s cool!! Thanks for sharing :)

    • MaggiWuerze
      link
      fedilink
      arrow-up
      1
      ·
      3 months ago

      What could that glass be used for, other than building houses? Can you sink in the deeper parts like NASA feared when they send the first people up?

      • CleoTheWizard@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        3 months ago

        The glass just has high angularity like the other particles it comes from so while in and of itself it isn’t useful, highly angular particles make for better interlocking when made into cements.

        And I don’t think they’re as worried about the depth of the dust in the highlands but it definitely makes exploring craters on foot impossible with the regolith present. You could absolutely get buried in it if the depth of the dust is 10m deep in some spots. We have a lot of concerns with the dust and how we can make long term survivable hardware which is part of what I worked on.

        • MaggiWuerze
          link
          fedilink
          arrow-up
          1
          ·
          edit-2
          3 months ago

          but it definitely makes exploring craters on foot impossible with the regolith present

          But the rovers with their oversized wheels are fine?

          • CleoTheWizard@lemmy.world
            link
            fedilink
            English
            arrow-up
            3
            ·
            3 months ago

            Theres some cool reasons behind that and I encourage you to look into it but the summary is that a lot of our rovers use those oversized wheels so they don’t sink and instead spread their weight over the top of it. The regolith does get more compact as you go down, so that also helps prevent sinking all the way to the bottom.

            The other part is that both for rovers and astronauts we map out areas of high risk and avoid them. The Apollo astronauts landed in a specific spot and had certain areas to explore for that exact reason.

            Then when it comes to the LRV (the moon buggy) that we brought up there, that thing has very lightweight tires that are essentially just mesh wire. Helps to spread the load and they deform easily to get better traction in the loose rock.

            I had the pleasure of handling engineering replicas of the tires on the LRV and also newer generation martian rover tires. Including another engineering sample of the wheels on perseverance. NASA has a giant soil bin with a material that mimics the regolith that they use to test those wheels to prevent the rovers from sinking. Basically just attaching the wheels to a fake rover rig, loading it with weights, and then they drive it and track it in real time 3D space to measure slip and sinkage and all that.