Ok getting some real sciency answers which proves you are way better than I am. Can you guys and gals break some of it down like I am 5 or so?

  • Jul (they/she)@piefed.blahaj.zone
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    25 days ago

    You pick a point of reference. Most things use the plane of the solar system or the Milkway Galaxy and the general direction the earth’s north faces as “up”. And then angle of inclination/declination from there.

    • Rhaedas@fedia.io
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      25 days ago

      Correct, it’s all about what’s closest to the scale of movement you’re needing. Close to a body, you’ll likely line up with its rotation if nothing else. Away from a body, you use the next frame of reference that makes sense. That could be the next closest body’s plane of rotation (which could be the same as the solar system, but not a given, i.e Uranus), the solar system itself, or if approaching another system, line up with its plane. You don’t have to do this, a polar orbit is just as valid as one within the plane.

    • frongt@lemmy.zip
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      25 days ago

      This. There is, generally, no up or down, unless you specifically choose a frame of reference. That might be the earth, the Milky Way, or your own geosynchronous satellite.

      • teawrecks@sopuli.xyz
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        24 days ago

        You always have to define what “up” and “down” mean. On earth, we define “down” as the direction gravity pulls, and “up” as the opposite of that. But out in space, that definition obviously doesn’t make sense, which is why you’re asking.

        So either,

        1. there is no up or down anymore, or
        2. we come up with a new definition

        One of the common definitions astronauts come up with is relative to the “plane of our solar system”. If you can imagine a giant piece of paper cutting through the middle of the sun, and extending out so big that it also cuts through all all the planets that are orbiting it, that’s called the plane of the solar system. Then we say “up” is one side of that paper, and “down” is the other side.

        But again, that only works as a convention in our solar system. Wherever you are, you have to define up and down, because they don’t mean anything by themselves.

        • agamemnonymous@sh.itjust.works
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          24 days ago

          Buckminster Fuller didn’t like to use “up” or “down”, preferring “in” (towards the center of gravity) and “out” (away from the center of gravity). “Downstairs” becomes “instairs”, “upstairs” becomes “outstairs”. A tad pedantic for casual conversations on Earth, but highlights the central issue.

          • teawrecks@sopuli.xyz
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            24 days ago

            Knowing that the nature of gravity is just the curvature of spacetime, it seems arbitrary either way. I But I hadn’t heard that, interesting. Like that other commenter, my first thought was “the enemy gate is down”.