7 ms·

I'm surprised the article doesn't mention the potential fast track to Kessler syndrome, the name for a phenomenon in which it becomes impossible to safely put t

I'm surprised the article doesn't mention the potential fast track to Kessler syndrome, the name for a phenomenon in which it becomes impossible to safely put things in orbit because every object placed in orbit is rapidly impacted and disintegrated into more debris in orbit. Purposely injecting debris into orbit, even if it's at a low orbit, seems not good!

H8crilA 4y ago
This will really go out of hand when WW3 starts and all the intelligence gathering satellites will become targets. Not that it's the most important thing in a global war, but we might also successfully block all exit paths from this planet with large amounts of very fast and deadly debris.
- yodon 4y ago
  WW3 almost certainly also means no more communications satellites and no more weather satellites, in addition to no more humans in space. It would likely also mean nuclear winter and many other bad things, but permanently denying use of satellites is likely the first global cost of WW3.
  - robonerd 4y ago
    Nuclear Winter has been generally discredited by modern modelling. The whole premise was likely politically motivated by scientists who wanted to make nuclear war less likely to occur, by dissuading politicians with this yarn. (A true noble lie.) Criticism of the hypothesis was muted by few scientists wanting to risk the perception of supporting nuclear war. As for "permanently denying use of satellites", this is only partially true. High orbits would be fucked for millennia, but LEO would mostly clear up before the century is out. I know that seems 'forever', but it isn't. Also, depending on the severity of the debris, interplanetary exploration would not necessarily be out of the picture; if the debris is severe enough that a GSO satellite has a 99% chance of being destroyed within a year, then that orbit is as good as ruined. But if you only plan to pass through that region for a few hours, not spend a whole year there, you might be able to do that if you can tolerate some risk. It'd be like running across a highway, except the cars move faster than bullets and won't brake for you. If you hang out in the middle of the road you are certain to get hit. If you time it right and run across, you have a chance of getting through.
    - yodon 4y ago
      If you go back a bit farther, I think you'll find the work on nuclear winter actually came out of work done at Cornell to try to model the result of a large object impacting the earth 65 million years ago to kill off the dinosaurs. Amazingly enough, one of the hardest parts of the dinosaur extinction work was figuring out how a localized impact like that could kill enough things to cause an extinction, and that part came from the atmospheric modelers. After doing that modeling work, they realized the parallels with a nuclear conflict and produced the nuclear winter projections.
      - ncmncm 4y ago
        Then it turned out everything was cooked, not frozen.
      - robonerd 4y ago
        I think there's little doubt that tons of soot and ash in the upper atmosphere can cause periods of global cooling. The problem with the nuclear winter hypothesis is in the link between nuclear war and tons of soot in the stratosphere. These nuclear winter models make a lot of assumptions about the likelihood of a modern cities turning into firestorms and the amount of soot they would generate, the amount of soot lifted into the stratosphere by the fireball, and the amount of soot that stays there instead of precipitating out.
phendrenad2 4y ago
Does anyone actually believe in that? Surely most space debris doesn't form a stable orbit, but falls back to earth after a few collisions.
- bagels 4y ago
  How often do you think an individual piece of debris is impacting other objects? Most space debris starts as something in orbit, and if it's at a high enough altitude, most pieces do indeed stay in orbit. There is clear precedence for this. https://swfound.org/media/6575/swf_iridium_cosmos_collision_fact_sheet_updated_2012.pdf https://swfound.org/media/6575/swf_iridium_cosmos_collision_... "Analysis by both NASA and outside experts indicates that more than half of the Iridium debris will remain in orbit for at least 100 years, and much of the Cosmos debris will remain in orbit at least 20 to thirty years."
- mcguire 4y ago
  Objects in orbit are primarily cleared by atmospheric drag, with two major variables: height of perigee (lower causes more drag) and object mass (lighter objects are slowed more). Following an impact, some of the debris will be cleared quickly, but some will not. "On 11 January 2007, China conducted an anti-satellite missile test in which one of their FY-1C weather satellites was chosen as the target. The collision occurred at an altitude of 865 kilometres, when the satellite with a mass of 750 kilograms was struck in a head-on-collision by a kinetic payload traveling with a speed of 8 km/s (18,000 mph) in the opposite direction. The resulting debris orbits the Earth with a mean altitude above 850 kilometres, and will likely remain in orbit for decades or centuries.[18]" (https://en.wikipedia.org/wiki/Kessler_syndrome#Anti-satellite_missile_tests https://en.wikipedia.org/wiki/Kessler_syndrome#Anti-satellit...) Kessler syndrome requires the rate of debris creation be greater than the rate of clearing and the rate of clearing in higher orbits is very slow. https://amostech.com/TechnicalPapers/2012/Orbital_Debris/NIKOLAEV.pdf https://amostech.com/TechnicalPapers/2012/Orbital_Debris/NIK...
  - phendrenad2 4y ago
    > will likely remain in orbit for decades or centuries How much debris though? If I put orange juice in my coffee mug, after a few runs through the dishwasher there may technically be a few particles of orange juice left, but my taste buds probably won't collide with it.
photochemsyn 4y ago
The article briefly mentions it... not sure how many per 'clump' though: > "Going back to the needles, in case you’re wondering, despite the planned obsolescence, as of 2019, a few dozen clumps of them remain in orbit and are closely tracked..."
- JKCalhoun 4y ago
  I assume static charge is what clumped them. I assume too that is why the initial launch "failed to disperse".
robonerd 4y ago
WW3 will likely make a mess of orbit, particularly LEO. However most of the debris that intersects LEO will decay in the order of years to tens of years. After the war (assuming anybody is in any shape to be sending stuff to space in the first place) I think communication satellites in LEO will become the norm (moreso than it already is becoming.) This would be the obvious response to higher orbits being ruined by debris. But such a war would be very bad in many ways, and if this happens I don't think worrying about space will be high on your list of personal priorities.
- idealmedtech 4y ago
  LEO is too susceptible to interference (of the physical, not radio, kind) for any serious digital communications infrastructure to be placed there. I could see laser-based swarms of comms satellites being used (cubesat size, not starlink size), but I don't think the economics are there quite yet.
  - robonerd 4y ago
    It's not clear what exactly you mean by physical interference, but either way I think you're mistaken. Starlink is already proving the viability of launching huge constellations of fairly large (a ton or so) LEO satellites. If you're talking about debris grounding these constellations, that's a problem that resolves itself given enough time, as that debris deorbits naturally. If you're talking about intentional physical interference, aka anti-satellite weapons, the solution to that is having the ability to rapidly replenish the constellation (SpaceX is good at this, and with Starship they'll be even better at it; hundreds of replacement satellites with a single launch.) In the event of a war, a constellation could be kept operational through the brute force of launching more satellites faster than they're destroyed. Of course this will make a huge mess, but that's what wars do. Anyway, they're going forward with this already. The National Defense Space Architecture calls for a very large constellation of LEO communication satellites forming a mesh network using inter-satellite laser links. Starlink is likely dual-use technology and has been intended as such from the start.
    - 4y ago

H8crilA 4y ago

This will really go out of hand when WW3 starts and all the intelligence gathering satellites will become targets. Not that it's the most important thing in a global war, but we might also successfully block all exit paths from this planet with large amounts of very fast and deadly debris.

yodon 4y ago
WW3 almost certainly also means no more communications satellites and no more weather satellites, in addition to no more humans in space. It would likely also mean nuclear winter and many other bad things, but permanently denying use of satellites is likely the first global cost of WW3.
- robonerd 4y ago
  Nuclear Winter has been generally discredited by modern modelling. The whole premise was likely politically motivated by scientists who wanted to make nuclear war less likely to occur, by dissuading politicians with this yarn. (A true noble lie.) Criticism of the hypothesis was muted by few scientists wanting to risk the perception of supporting nuclear war. As for "permanently denying use of satellites", this is only partially true. High orbits would be fucked for millennia, but LEO would mostly clear up before the century is out. I know that seems 'forever', but it isn't. Also, depending on the severity of the debris, interplanetary exploration would not necessarily be out of the picture; if the debris is severe enough that a GSO satellite has a 99% chance of being destroyed within a year, then that orbit is as good as ruined. But if you only plan to pass through that region for a few hours, not spend a whole year there, you might be able to do that if you can tolerate some risk. It'd be like running across a highway, except the cars move faster than bullets and won't brake for you. If you hang out in the middle of the road you are certain to get hit. If you time it right and run across, you have a chance of getting through.
  - yodon 4y ago
    If you go back a bit farther, I think you'll find the work on nuclear winter actually came out of work done at Cornell to try to model the result of a large object impacting the earth 65 million years ago to kill off the dinosaurs. Amazingly enough, one of the hardest parts of the dinosaur extinction work was figuring out how a localized impact like that could kill enough things to cause an extinction, and that part came from the atmospheric modelers. After doing that modeling work, they realized the parallels with a nuclear conflict and produced the nuclear winter projections.
    - ncmncm 4y ago
      Then it turned out everything was cooked, not frozen.
    - robonerd 4y ago
      I think there's little doubt that tons of soot and ash in the upper atmosphere can cause periods of global cooling. The problem with the nuclear winter hypothesis is in the link between nuclear war and tons of soot in the stratosphere. These nuclear winter models make a lot of assumptions about the likelihood of a modern cities turning into firestorms and the amount of soot they would generate, the amount of soot lifted into the stratosphere by the fireball, and the amount of soot that stays there instead of precipitating out.

phendrenad2 4y ago

Does anyone actually believe in that? Surely most space debris doesn't form a stable orbit, but falls back to earth after a few collisions.

bagels 4y ago
How often do you think an individual piece of debris is impacting other objects? Most space debris starts as something in orbit, and if it's at a high enough altitude, most pieces do indeed stay in orbit. There is clear precedence for this. https://swfound.org/media/6575/swf_iridium_cosmos_collision_fact_sheet_updated_2012.pdf https://swfound.org/media/6575/swf_iridium_cosmos_collision_... "Analysis by both NASA and outside experts indicates that more than half of the Iridium debris will remain in orbit for at least 100 years, and much of the Cosmos debris will remain in orbit at least 20 to thirty years."
mcguire 4y ago
Objects in orbit are primarily cleared by atmospheric drag, with two major variables: height of perigee (lower causes more drag) and object mass (lighter objects are slowed more). Following an impact, some of the debris will be cleared quickly, but some will not. "On 11 January 2007, China conducted an anti-satellite missile test in which one of their FY-1C weather satellites was chosen as the target. The collision occurred at an altitude of 865 kilometres, when the satellite with a mass of 750 kilograms was struck in a head-on-collision by a kinetic payload traveling with a speed of 8 km/s (18,000 mph) in the opposite direction. The resulting debris orbits the Earth with a mean altitude above 850 kilometres, and will likely remain in orbit for decades or centuries.[18]" (https://en.wikipedia.org/wiki/Kessler_syndrome#Anti-satellite_missile_tests https://en.wikipedia.org/wiki/Kessler_syndrome#Anti-satellit...) Kessler syndrome requires the rate of debris creation be greater than the rate of clearing and the rate of clearing in higher orbits is very slow. https://amostech.com/TechnicalPapers/2012/Orbital_Debris/NIKOLAEV.pdf https://amostech.com/TechnicalPapers/2012/Orbital_Debris/NIK...
- phendrenad2 4y ago
  > will likely remain in orbit for decades or centuries How much debris though? If I put orange juice in my coffee mug, after a few runs through the dishwasher there may technically be a few particles of orange juice left, but my taste buds probably won't collide with it.

photochemsyn 4y ago

The article briefly mentions it... not sure how many per 'clump' though: > "Going back to the needles, in case you’re wondering, despite the planned obsolescence, as of 2019, a few dozen clumps of them remain in orbit and are closely tracked..."

JKCalhoun 4y ago
I assume static charge is what clumped them. I assume too that is why the initial launch "failed to disperse".

robonerd 4y ago

WW3 will likely make a mess of orbit, particularly LEO. However most of the debris that intersects LEO will decay in the order of years to tens of years. After the war (assuming anybody is in any shape to be sending stuff to space in the first place) I think communication satellites in LEO will become the norm (moreso than it already is becoming.) This would be the obvious response to higher orbits being ruined by debris. But such a war would be very bad in many ways, and if this happens I don't think worrying about space will be high on your list of personal priorities.

idealmedtech 4y ago
LEO is too susceptible to interference (of the physical, not radio, kind) for any serious digital communications infrastructure to be placed there. I could see laser-based swarms of comms satellites being used (cubesat size, not starlink size), but I don't think the economics are there quite yet.
- robonerd 4y ago
  It's not clear what exactly you mean by physical interference, but either way I think you're mistaken. Starlink is already proving the viability of launching huge constellations of fairly large (a ton or so) LEO satellites. If you're talking about debris grounding these constellations, that's a problem that resolves itself given enough time, as that debris deorbits naturally. If you're talking about intentional physical interference, aka anti-satellite weapons, the solution to that is having the ability to rapidly replenish the constellation (SpaceX is good at this, and with Starship they'll be even better at it; hundreds of replacement satellites with a single launch.) In the event of a war, a constellation could be kept operational through the brute force of launching more satellites faster than they're destroyed. Of course this will make a huge mess, but that's what wars do. Anyway, they're going forward with this already. The National Defense Space Architecture calls for a very large constellation of LEO communication satellites forming a mesh network using inter-satellite laser links. Starlink is likely dual-use technology and has been intended as such from the start.
  - 4y ago