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Is Kessler syndrome the Great Filter (https://en.wikipedia.org/wiki/Great_Filter https://en.wikipedia.org/wiki/Great_Filter)? As in, is it the thing that makes

Is Kessler syndrome the Great Filter (https://en.wikipedia.org/wiki/Great_Filter https://en.wikipedia.org/wiki/Great_Filter)? As in, is it the thing that makes it so no one else has broken out of their planet to come visit us? I could totally see it being the case that as soon as a civilization gets good enough at putting stuff into space, they start putting a lot of stuff into space and then things start crashing into each other to the point that they can’t ever launch any more things into space and become stuck. Trapped by the artifacts of their own progress

ljsprague 2y ago
I would guess that it would still be possible to send things beyond earth's orbit with only a low probability of collision with debris but perhaps I'm wrong.
- to11mtm 2y ago
  "Low" is tough to say until someone does some proper sort of 'true mapping' of space debris in the range somehow. Protection would require a lot of complexity and cost due to the need for shielding and the delta-v to move it up there.
  - JumpCrisscross 2y ago
    > until someone does some proper sort of 'true mapping' of space debris in the range somehow You look at which satellites poofed and then figure out the maximum extent their debris could have drifted.
    - mapt 2y ago
      That works a little bit when we're talking about one satellite poofing in a year based on a collision with another satellite, and not at all when we're talking about thousands of events a year, many of which are satellite-debris collisions too small to track (you only get one orbital vector), or between pieces of debris. Every collision generates hundreds, maybe thousands of pieces of debris, only the largest of which are trackable.
      - JumpCrisscross 2y ago
        Not really. There are uncertainty bands. But based on the collision you know which orbits are spoiled for about how long.
  - vlovich123 2y ago
    Rather than protection on each rocket, couldn't you just send a bunch of fortified rockets that absorb the debris during a collision but don't emit anything. Do that a few times and then all other rockets just reuse the path that was cut?
    - mapt 2y ago
      Orbit is not a location. Orbit is a group of velocity-location vectors which form a stable loop around a body, without intersecting that body. Imagine a bullet circling your head at mach 25. Now imagine a second bullet, circling your head at a slightly different angle, at a slightly different distance from your head. There's a chance that they could collide, and the resulting explosion would leave a great deal of dust... on a mixture of velocities, still circling your head. Now add a third bullet, also on a slightly different vector; Make sure that it doesn't collide with any of that dust! The actual situation is we aren't dealing with 3 bullets or 100 bullets, we have ~170 million objects orbiting the Earth, and only around 50,000 are large enough to track. They are all moving fast enough in relation to each other that a collision would result in a sizable explosion, not an elastic agglomeration. We have no way of removing them. The good news is that there is a large volume of space for them to exist in. The bad news is that as we continue to fill it up, odds of collisions increase, and every collision spawns many, many more objects.
      - vlovich123 2y ago
        You’ve explained what Kessler syndrome is but not why my idea doesn’t work. I’m saying send reinforced rockets through the orbits that absorb the collision instead of generating more dust. That should let you clear a path through all orbits that intersect your path. It’s hard to do and the 3d aspect of it might make it expensive but conceptually it could be a solution. Or use super powerful lasers (potentially mounted on a satellite) to deorbit the dust
        immibis 2y ago
        It takes about 90 minutes to complete a low earth orbit. A rocket can't hover in place for 90 minutes at the same altitude, then increase its altitude by its height and repeat. It doesn't have enough fuel for that.
- 0x1ceb00da 2y ago
  Every launch failure will result in more debris and even lower probability of a successful future launch.
lxgr 2y ago
I'd consider it much less likely than e.g. nuclear or maybe chemical/biological warfare. Kessler syndrome (if even achievable with current technology) would be a major bummer for science and the global economy for a couple of decades (no more Starlink, but we still have good old geostationary satellites, so no ships and airplanes would get disconnected as a result), or at worst centuries, but would otherwise not form any threat to civilization, whereas nuclear winter is already very capable of wiping it out.
- fragmede 2y ago
  > if even achievable with current technology Launching a nail bomb into orbit would've been possible as soon as we were able to get into space, the only question is motivation. A terrorist state, say North Korea, threaten the rest of the planet and demand concessions once they're able to get any significant mass into orbit.
  - Cthulhu_ 2y ago
    I'd say intentionally destroying space assets etc should be considered an act of war (compare attacking another nation's ship in international waters), NK wouldn't have a chance and they could be put into space lockdown where any launches are intercepted.
    - PittleyDunkin 2y ago
      Good luck dragging people into war over space trash that doesn't even benefit most peoples' lives in any material sense.
      - lxgr 2y ago
        Are you sure that you have never looked at a weather forecast (or received a severe weather warning), crossed an ocean in an airplane, used GPS (or another satellite-based navigation system, or eaten food farmed using precision automated equipment that does), which are just the first things coming to mind that would be much harder without satellites?
kmeisthax 2y ago
No. The space junk at a given orbit makes it unviable to put more satellites in that orbit, but launching beyond that orbit is still viable.
- throwaway888889 2y ago
  How can you get past that orbit if there is all this junk destroying your rockets????
  - Retric 2y ago
    Ideally a satellite is in a given orbit for years. If junk is destroying it in weeks or even months you’ve got a massive issue. However a rocket is spending in a seconds in that same orbit. Thus a rocket passing through may only have say 1:10,000 odds of a collision on its way to mars while satellites are getting shredded.
    - ryankshaw 2y ago
      Thanks for the explanation. So you don’t think the 1:10k odds compounded over every space launch are enough to be a problem? I was thinking that maybe as you get to a scale where you have things coming and going all the time, and each time they have to pass through the debris layer, and if they have bad luck they become part of that debris, that eventually you get to a point where even just passing through that layer is untenable. But you don’t think that is likely even for a society sending out interplanetary vessels every day?
      - Retric 2y ago
        A problem, but not an insurmountable one. Being hit isn’t the same as being destroyed, you can track and avoid large objects, and small are survivable in the short term. https://en.wikipedia.org/wiki/Whipple_shield https://en.wikipedia.org/wiki/Whipple_shield Collisions however keep adding up until a satellite fails. Second an outbound rocket need not be in orbit, so if it is destroyed that may not result in extra orbital debris the overwhelming majority of mass could fall back to earth. Also, Kessler syndrome isn’t a forever thing. There’s a reason planets have rings not debris clouds. It’s possible to have a steady state where the rate you’re making it worse is balanced with the rate things are naturally clearing.

ljsprague 2y ago

I would guess that it would still be possible to send things beyond earth's orbit with only a low probability of collision with debris but perhaps I'm wrong.

to11mtm 2y ago
"Low" is tough to say until someone does some proper sort of 'true mapping' of space debris in the range somehow. Protection would require a lot of complexity and cost due to the need for shielding and the delta-v to move it up there.
- JumpCrisscross 2y ago
  > until someone does some proper sort of 'true mapping' of space debris in the range somehow You look at which satellites poofed and then figure out the maximum extent their debris could have drifted.
  - mapt 2y ago
    That works a little bit when we're talking about one satellite poofing in a year based on a collision with another satellite, and not at all when we're talking about thousands of events a year, many of which are satellite-debris collisions too small to track (you only get one orbital vector), or between pieces of debris. Every collision generates hundreds, maybe thousands of pieces of debris, only the largest of which are trackable.
    - JumpCrisscross 2y ago
      Not really. There are uncertainty bands. But based on the collision you know which orbits are spoiled for about how long.
- vlovich123 2y ago
  Rather than protection on each rocket, couldn't you just send a bunch of fortified rockets that absorb the debris during a collision but don't emit anything. Do that a few times and then all other rockets just reuse the path that was cut?
  - mapt 2y ago
    Orbit is not a location. Orbit is a group of velocity-location vectors which form a stable loop around a body, without intersecting that body. Imagine a bullet circling your head at mach 25. Now imagine a second bullet, circling your head at a slightly different angle, at a slightly different distance from your head. There's a chance that they could collide, and the resulting explosion would leave a great deal of dust... on a mixture of velocities, still circling your head. Now add a third bullet, also on a slightly different vector; Make sure that it doesn't collide with any of that dust! The actual situation is we aren't dealing with 3 bullets or 100 bullets, we have ~170 million objects orbiting the Earth, and only around 50,000 are large enough to track. They are all moving fast enough in relation to each other that a collision would result in a sizable explosion, not an elastic agglomeration. We have no way of removing them. The good news is that there is a large volume of space for them to exist in. The bad news is that as we continue to fill it up, odds of collisions increase, and every collision spawns many, many more objects.
    - vlovich123 2y ago
      You’ve explained what Kessler syndrome is but not why my idea doesn’t work. I’m saying send reinforced rockets through the orbits that absorb the collision instead of generating more dust. That should let you clear a path through all orbits that intersect your path. It’s hard to do and the 3d aspect of it might make it expensive but conceptually it could be a solution. Or use super powerful lasers (potentially mounted on a satellite) to deorbit the dust
      - immibis 2y ago
        It takes about 90 minutes to complete a low earth orbit. A rocket can't hover in place for 90 minutes at the same altitude, then increase its altitude by its height and repeat. It doesn't have enough fuel for that.
0x1ceb00da 2y ago
Every launch failure will result in more debris and even lower probability of a successful future launch.

lxgr 2y ago

I'd consider it much less likely than e.g. nuclear or maybe chemical/biological warfare. Kessler syndrome (if even achievable with current technology) would be a major bummer for science and the global economy for a couple of decades (no more Starlink, but we still have good old geostationary satellites, so no ships and airplanes would get disconnected as a result), or at worst centuries, but would otherwise not form any threat to civilization, whereas nuclear winter is already very capable of wiping it out.

fragmede 2y ago
> if even achievable with current technology Launching a nail bomb into orbit would've been possible as soon as we were able to get into space, the only question is motivation. A terrorist state, say North Korea, threaten the rest of the planet and demand concessions once they're able to get any significant mass into orbit.
- Cthulhu_ 2y ago
  I'd say intentionally destroying space assets etc should be considered an act of war (compare attacking another nation's ship in international waters), NK wouldn't have a chance and they could be put into space lockdown where any launches are intercepted.
  - PittleyDunkin 2y ago
    Good luck dragging people into war over space trash that doesn't even benefit most peoples' lives in any material sense.
    - lxgr 2y ago
      Are you sure that you have never looked at a weather forecast (or received a severe weather warning), crossed an ocean in an airplane, used GPS (or another satellite-based navigation system, or eaten food farmed using precision automated equipment that does), which are just the first things coming to mind that would be much harder without satellites?

kmeisthax 2y ago

No. The space junk at a given orbit makes it unviable to put more satellites in that orbit, but launching beyond that orbit is still viable.

throwaway888889 2y ago
How can you get past that orbit if there is all this junk destroying your rockets????
- Retric 2y ago
  Ideally a satellite is in a given orbit for years. If junk is destroying it in weeks or even months you’ve got a massive issue. However a rocket is spending in a seconds in that same orbit. Thus a rocket passing through may only have say 1:10,000 odds of a collision on its way to mars while satellites are getting shredded.
  - ryankshaw 2y ago
    Thanks for the explanation. So you don’t think the 1:10k odds compounded over every space launch are enough to be a problem? I was thinking that maybe as you get to a scale where you have things coming and going all the time, and each time they have to pass through the debris layer, and if they have bad luck they become part of that debris, that eventually you get to a point where even just passing through that layer is untenable. But you don’t think that is likely even for a society sending out interplanetary vessels every day?
    - Retric 2y ago
      A problem, but not an insurmountable one. Being hit isn’t the same as being destroyed, you can track and avoid large objects, and small are survivable in the short term. https://en.wikipedia.org/wiki/Whipple_shield https://en.wikipedia.org/wiki/Whipple_shield Collisions however keep adding up until a satellite fails. Second an outbound rocket need not be in orbit, so if it is destroyed that may not result in extra orbital debris the overwhelming majority of mass could fall back to earth. Also, Kessler syndrome isn’t a forever thing. There’s a reason planets have rings not debris clouds. It’s possible to have a steady state where the rate you’re making it worse is balanced with the rate things are naturally clearing.