• Echo Dot@feddit.uk
      link
      fedilink
      English
      arrow-up
      2
      ·
      7 hours ago

      Large boulder is a state of mind. It achieved an awful lot that day and was feeling especially pleased with itself thus the honorific.

  • mnemonicmonkeys@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    22
    arrow-down
    5
    ·
    edit-2
    21 hours ago

    Complaining about Kressler Syndrome

    Complaining about Starlink

    Pick one, asshole. As shitty as Musk is, Starlink is in too low of an orbit to cause Kressler Syndrome

    • Echo Dot@feddit.uk
      link
      fedilink
      English
      arrow-up
      5
      arrow-down
      1
      ·
      edit-2
      7 hours ago

      Every time somebody mentions Kessler syndrome they always seem to forget that low earth orbit is an area literally bigger than the earth’s surface. There’s about 10,000 of them and they are spread out over an area bigger than the surface of the earth. Meanwhile there are way more than 10,000 trucks in the world and apparently they are twice the size, and yet there are huge swaths of land that do not currently have a truck on them. I think we’ll be okay.

      Although I do accept they are probably irritating for astronomers.

      • Rossphorus@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        edit-2
        2 hours ago

        Collisions aren’t theoretical, near misses are so common that there’s an entire department at NASA dedicated to detecting them and warning satellite owners to adjust course, I know because we were contacted about a possible collision involving our cubesat. Prior to megaconstellations being deployed if humanity stopped adjusting satellite orbits there would be a collision within a month, now there would be a collision within 5 days. It’s only a matter of time until both satellites on a collision course don’t have the ability to adjust course (engine failure or no propulsion/fuel/comms). In the event of a Carrington-style solar flare there’s a good chance a decent percentage of satellites would be knocked out, making this hypothetical into a reality. Further, we can only currently track objects down to about 10cm, but NASA estimates suggest about 500,000 objects exist between 1-10cm in size in LEO.

        • Echo Dot@feddit.uk
          link
          fedilink
          English
          arrow-up
          2
          arrow-down
          1
          ·
          2 hours ago

          A collision event is considered any event where a satellite passes within a ridiculously large distance of another satellite. It doesn’t mean they’re necessarily going to collide.

          In the incredibly unlikely event that all of the things that you have stated happen everything would clear out within 12 to 18 months which given the fact you’ve just decimated 21st century civilisation is probably the least of everyone’s concerns anyway.

          • Rossphorus@lemmy.world
            link
            fedilink
            English
            arrow-up
            1
            ·
            edit-2
            42 minutes ago

            A solar flare is just one example of many possible causes. There are plenty of other ones. You didn’t touch on any of the others so let me explain - NASA reports on small satellite missions show that about 40% of satellites experience at least partial mission failure within their lifetime. Studies have shown the leading cause of satellite failure is propulsion systems, responsible for about half of all failures. This is not uncommon at all.

            Most altitude ranges in LEO still have debris from decades ago, the exception being below 300km, which is basically still in the atmosphere. Unfortunately, debris strikes have regularly produced debris that are flung into higher orbits, so even collisions between satellites in this range are dangerous.

            Edit: I also forgot to mention, the five day estimate (now three days actually) wasn’t for a close-call, it was for a debris-generating event.

    • bluGill@fedia.io
      link
      fedilink
      arrow-up
      1
      arrow-down
      2
      ·
      12 hours ago

      The only worry about low earth orbit is something survives reentry enough to become a bomb. these are enough to destroy a house if that happens - my undertanding is this can’t happen but if they did

      • mnemonicmonkeys@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        4
        ·
        edit-2
        7 hours ago

        Starlink satellites aren’t large enough to survive the heat of reentry. A more likely concern is the various materials vaporizing and dispersing into the atmosphere, as was mentioned in the article.

        That being said, calling them “heavy metals” like the interviewee did is rather dubious. We’re not talking about lead, as what most readers imagine when they hear that term. It’s mainly aluminum and copper. The person interviewed is picking their words to overexaggerate their claims

      • Echo Dot@feddit.uk
        link
        fedilink
        English
        arrow-up
        3
        ·
        7 hours ago

        Well if the atmosphere decides it’s going to have a day off then I’ll start to worry.

        The temperatures generated by reentry are not just hot enough to vaporize a satellite they are way beyond hot enough to vaporize a satellite. I can’t imagine any scenario where a satellite survives. In any case the vast majority of the orbits are controlled, Which means they come down over the ocean.

        • bluGill@fedia.io
          link
          fedilink
          arrow-up
          1
          arrow-down
          2
          ·
          4 hours ago

          Reentry survival is a materials question. If someone decides heat resistant ceramic is cheaper all is well until that cames down and we discover it doesn’t vaporize like iron (or whatever they make it with)

          • Echo Dot@feddit.uk
            link
            fedilink
            English
            arrow-up
            1
            ·
            edit-2
            2 hours ago

            If someone decides heat resistant ceramic is cheaper all is well until that cames down and we discover it doesn’t vaporize like iron

            Yeah because that’s likely. You do realise that everything that goes up has to pass inspections right they don’t just let people do random things. Anything that gets put in orbit is verified by people way smarter than you or me. You really don’t need to worry about it.

            There’s lots of stuff in this world to be concerned about but being hit by the orbiting asteroid is absolutely not one of them.

  • RamRabbit@lemmy.world
    link
    fedilink
    English
    arrow-up
    43
    ·
    edit-2
    1 day ago

    Yep, they are in Low Earth Orbit. A place that has a very, very small amount of air, so the satellites experience drag, lose speed, eventually the propellant tanks run dry, and they burn up in the atmosphere. The ISS experiences the same thing, which is why its altitude slowly falls, then you see a sharp increase as they push to a slightly higher orbit.

    At the altitude the SpaceX satellites are at, they only passively stay up for a few years. With the onboard propulsion giving them each another few years.

      • Echo Dot@feddit.uk
        link
        fedilink
        English
        arrow-up
        3
        ·
        7 hours ago

        I don’t remember that happening. I would actually be surprised if a satellite would survive reentry with basically anything left of it. If you want to return something from orbit you need heat shield or you’re not getting it back.

        Even the ISS is expected to completely burn up and that’s much higher mass than a starlink satellite

      • BarneyPiccolo@lemmy.today
        link
        fedilink
        English
        arrow-up
        2
        ·
        edit-2
        11 hours ago

        A grand? Then I’m keeping it. I can make more as a roadside tourist attraction. Or maybe I sell it to the Chinese or Bezos or something. You want your toy back, Musk? Pay up, you cheap bastard!

      • Iconoclast@feddit.uk
        link
        fedilink
        English
        arrow-up
        8
        ·
        18 hours ago

        It wasn’t from a starlink satellite though.

        which the U.S. aerospace company SpaceX later admitted was part of a cargo trunk for its Crew Dragon spacecraft.

        Source

  • Em Adespoton@lemmy.ca
    link
    fedilink
    English
    arrow-up
    15
    ·
    24 hours ago

    Half the size of a pickup truck… a Mazda compact, or a jacked up GMC Hemi half ton?

    Even just saying Ford F150 gives a lot of leeway.

    • Echo Dot@feddit.uk
      link
      fedilink
      English
      arrow-up
      1
      ·
      edit-2
      7 hours ago

      They’re about the size of a large flat screen TV. I have no idea why they reached the pickup trucks, they might have the width but they’re only a couple of inches thick. A flat screen is a much better analogy.

  • halcyoncmdr@piefed.social
    link
    fedilink
    English
    arrow-up
    7
    ·
    21 hours ago

    Yeah that’s what happens to absolutely everything in Low Earth Orbit in just a few years. Well, unless you keep pushing them back up like we do to the International Space Station.

    These satellites are doing exactly what they’re intended to do. These are actually pretty small satellites overall, there are a lot up there quite a bit larger that deorbit and burn up on re-entry just fine as well.

    That’s part of the reason things are sent to LEO specifically, because their orbits naturally degrade and they naturally deorbit themselves without needing any assistance or fuel. It also means if a satellite in LEO fails quicker than planned, is put in an incorrect orbit due to a launch issue, or just failed prematurely, it will fail-safe and deorbit without any assistance.