If you hadn't had enough scary sounding possible future calamities that you as an individual have no control over to worry about, here's another. My anxiety system for these kinds of things broke back when peak oil turned out to not be a thing (well as described). There lots of things to be concerned about where we as individuals can make better choices, such as sustainable living and not contributing to carbon emissions, but stuff like this, while something I'm not going to ignore because it's at the very least interesting, I can't feel anxiety about.
I just don't have the capacity to be anxious every minute of my life for everything that could possibly go wrong for us someday in the future.
Peak oil kinda happened. All of the abundant easy to access oil is gone. We're gradually moving to other sources like offshore and fracking while using more technology in existing locations like pumping seawater into old wells to get more out of them.
Tech has done wonderful things to keep costs down, but it's a lot tougher to get that barrel of oil now days. I think there are, at least to some degree, costs being offset by increased risk. Deepwater horizon is a pretty obvious example. Groundwater contamination from fracking is another. I think the price per barrel has been on a steady downward trend, but I'd bet that including the environmental impact just from accessing (not burning) oil, we're paying more. I'm not aware of any such study.
In any case, we're the first, but also last technological civilization to use oil. If a wizard waved a magic wand, and we were suddenly sent back to a 1700's level of technology, i don't see how we'd be able to get much oil at all. It's not bubbling up out of the ground anywhere anymore. The easy stuff is gone. there's no way to get the hard stuff by hand.
The trick there is that most things are systems, rather than point variables. Just like you can't push down just one place in a bowl of water, you can't expect that the system will not respond to the change in variables. Whether it is Peak Oil, Kessler Syndrome, Global Warming, or Free Markets. People use extrapolation to scare others into some action, rarely are the predictions correct because other parts of the system have adapted.
Indeed. I've lived long enough to see a whole lot of TEOTWAWKI scenarios panicked about and either were duly mitigated by sensible people or simply failed to instantiate. "Y2K Bug" was an ideal example (chronic programming flaw could have knocked out computer systems worldwide and knocked humanity back to the Middle Ages, but was recognized as a solvable problem and was indeed solved).
At some point I looked at my own anxieties and simply decided to not be anxious: do what I could about what I could given resource (time included) constraints, be prepared for eventualities within reason, and otherwise carry on.
My biggest recurring concern now is how I'm not anxious. Should something horrible happen, I may be disconcertingly unconcerned - having done what I could in good faith, there is/was nothing else to do but accept reality and move on.
Instead of being anxious, our goal should be to fix things if we can, and plan mitigation strategies if we can't. Peak oil is a thing: by definition there is _some_ global maximum in produciton volume over a long enough chosen interval. It might turn out that the solution is built into the problem though, because price is a function of supply so we get a soft landing, especially if we plan ahead. And we should plan ahead. It's the same with Y2k. It was a serious problem, but we fixed it before it was a disaster.
The Mathusian Catastrophe has also failed to fully materialize because people are not bacteria, and so we planned ahead and are trying to control population and improve agricultural efficeincey. Did we do a perfect job? No, but we did better than bacteria.
Just because a doomsday scenario fails to emerge does not mean the problems were completely bunk.
So I'm guessing Stross thinks we should imagine what will happen if we don't do something about Kessler Syndrome, and then become motivated to do something about it.
Well, don't feel anxious. Charles Stross is a science fiction writer and dreaming up (or researching) interesting calamities pays his bills. If humans are an ant hill, you're just one ant, and unless you work for NASA, ESA, SpaceX, or (at the very least) have a prestigious professorship at a major university and/or serve as the science advisor to someone with real political power, there's nothing you need/can do about this one.
So relax, and enjoy a good setting for a dystopian story.
I can't find the source now, but some estimate that removing only a few of the largest boosters on orbit each year would decrease the cascade risk significantly, since those boosters represent a large fraction of the mass. This is a much smaller move than many other avoid-the-end-of-the-world suggestions given throughout the years.
Now: better modeling would probably help us determine whether Kessler syndrome will actually happen.
Scientists only figured out in the last decades what religions knew for millenia: people love to be told "the world is ending, give us money". Back when I was a teen, the coming ice age / famine of 2000 predicted by the Club of Rome was a serious problem for my educated (adult) friends. So was nuclear war.
Lists like [1] remind me of my extremely scary youth :)
Kessler Syndrome is a serious potential problem and it's certainly one people should be worrying about but it's mostly something that's only a problem for LEO where you have lots of things in a relatively small volume going very fast in different directions.
Further out in MEO where GPS satellites are there's a much greater volume, fewer satellites, and the satellites aren't moving as fast. There's no way Kessler Syndrome is going to start there. You do have a bunch of Russian satellites that loop in fast and close by the South Pole then go high and slow over the North, letting them spend most of their time being visible from Russia. Debris from from a cascade could kill one of those, which would cause debris that would kill some but not all of the GPS sats. It would be a relatively slow process compared to what would go on in LEO, though.
Satellites in GEO won't need to worry about Kessler at all. They're all in equatorial orbits, traveling in the same direction at the same speed. If one explodes its debris will only hit other satellites with the explosion velocity, not orbital velocity. So those should survive Kessler Syndrome fine, though you can't put any new ones there.
Also, Kessler Syndrom isn't forever. Satellites in LEO need to boost every once in a while to overcome atmospheric drag. As things get broken up their surface area to volume ratio increases and the fall out of orbit faster. Air density falls of exponentially with height so the lower reaches of orbit will become safe first. The inner reaches of LEO might be clear quickly but I have no idea how long it would be before orbit was totally clear.
Researchers at Texas A&M University[1] have been working on this problem with NASA JSC for years.
The approach has been to go after the large spent boosters (a few thousand of them), since they contain the most mass of any class of debris objects. Each upper-stage booster has a rocket nozzle that makes a great target for grappling.
As other comments have noted, the main issue is actually deciding to spend money bringing down orbital debris. As with many other issues we face, this is another case of kicking the can down the road, and we may not address it until the collision cascade has started :-/
Interesting paper where supercomputer was used to simulate the increase of particles greater than 10 cm in size over 100 years with high temporal resolution.
Results for BAU (business and usual) and BAU-d business as usual with decreasing breakup rate don't look so good: "linear growth of the catalog size with time, to ~65,000 objects by year 2100." 100 years from now there will be 50 conjunctions per day and 3 collisions per year.
Practically every form of debris removal is also a pretty good anti-satellite weapon.
Additionally, a not-too-unreasonable interpretation of current international treaties would lead one to conclude that piece of junk, inoperable satellite X (or a piece of debris that comes off of it) is still owned by country Y, interfering with it is a violation of Y's sovereignty, etc. This is to be contrasted with the seas where there are some kind of established norms about the wreckage of ships, abandoned ships, etc.
I kinda want to bone up on the relevant treaties and/or agreements about Earth orbit and other planets.
Interesting to think about, but I have a feeling that once you land on another celestial body, all property will be determined by homestead until a significant number of humans arrive later.
Imagine: there you are on Mars, building your habitat structure in a nice crater when the phone rings and NASA says, "Hey, you can't build there, since that's Russia's crater." Your response should be, "Well, when Russia gets here, they can move me off of their property."
The ability to enforce property rights is vastly reduced without a local presence representing your interests. Yes, there could be conflict over it here on Earth, but for the people actually off-world, it has no actual enforcement mechanism, especially on one-way missions. Any such treaties and agreements made now are purely for show and political gain by those parties involved.
It would be really easy to make a treaty covering the debris. The most horrible one would just require multilateral signoff on every removal action, but that would work just fine, every one is OK with clearing it out.
Isn't most of the debris moving in the same direction? I'm imagining that being in orbit is like being on the freeway, where the traffic is all running the same direction. Yes, getting hit by a car going 70 MPH would normally be catastrophic, but two cars bumping into each other around 70 MPH is not always a big deal.
Enough satellites are in polar/retrograde orbits to be an issue. Explosions from Chinese/US anti-satellite tests and accidental collisions go every which way, as well.
one degree of inclination difference with otherwise similar orbital elements upon impact translates to about .5%-1% of energy of a head-on/t-bone impact. at orbital velocities this is still mindblowingly devastating. you've basically reduced a 8km/s impact into a 40-80m/s which is in 90-180mph range. result is lots of debris created in both orbital planes as both sats (you're comparing cars, so i assume you want sat-sat impact) are totalled, solar panels shattered, etc.
and that's basically the smallest accidental collision in space you can imagine (not counting failed berthings/dockings and the like).
Orbital speeds are fast. LEO orbital speed is about 8km/s (about 18,000 mph). So the collision is not between two cars going at 70+-5 mph but 18,000+-1000 mph (say).
As the other comments mention, satellites also have different inclinations. Even a tiny difference of inclination projects a large speed on the axis along the two satellites, again due to the large speeds involved.
I believe that would be true of geosynchronous satellites, otherwise there would be no benefit to being geosynchronous. Any pieces that break off should alter their orbit enough to be out of the way.
Edit: I just got dinged for this comment, if there's a flaw in my reasoning or a study that refutes it please let me know.
> Even a fleck of shed paint a tenth of a millimeter across carries as much kinetic energy as a rifle bullet when it's traveling at orbital velocity
True, but most of the other objects near it are also at or near orbital speed, so what's the kinetic energy when compared to an object it would actually be likely to hit?
(The situation in Gravity made no sense to me. The shuttle encounters the debris field every 90 minutes...why was that debris not also orbiting the earth with roughly the same period as the shuttle?)
Is the solution a matter of countries agreeing to "lanes" for orbits that differ non-trivially? (e.g. 300-330km is reserved for equatorial orbits, 340-360 km is reserved for polar orbits, 380-400km is reserved for retrograde orbits)
Dumb question, but can't we put some giant blocks of single-piece kevlar-ish material in orbit? I imagine they would have no chance for breaking apart and would just serve as "bullet" catchers for these small pieces of debris.
More fiber optic cabling would be required. Local stations to retransmit information would have to be created (or existing infrastructure, such as cellphone towers, would be retrofitted).
And so on. We'd do fine, I guess. But not without an enormous cost.
It has some nice photos of some of the impacts that spacecraft have had.
---
Reading cstross's post at a tangent: I'm interested in how viable it is for a well funded technological terror group (like Aum Shinrikyo used to be) or "rogue nation" to dump a few tons of sand and grit (or depleted uranium, for the mass) into the correct orbits.
Stross has rarely-found pragmatism and realism in personally-held and publicly-shared opinions about space colonization for a popular science fiction author. While professionally he writes about a human future where we travel the stars, the TL;DR is personally, he holds that with our current understanding of physics, our meat sack bodies will never colonize space. Explore yes, but mass-exodus-colonization or even plant-seed-colonization-for-independent-colony is a pipe dream; he doesn't see the proof that we are capable of even colonizing the solar system, but leaves an open door to invite in that proof.
So a Kessler Cascade definitely sucks, but it isn't an "OMG, humanity loses its 'birthright to the stars'!" catastrophe because we can't GET to the stars for the foreseeable future, barring a Copernican-grade revolution in physics and accompanying engineering that opens a hitherto-unknown means of multiple magnitudes FTL transportation of the peta- to tetra-tons of mass associated with an en masse out-migration to the stars scenario.
This has interesting implications (I happen to strongly agree with his analysis) for how we set and carry out future policy, if you want to figure out means of nudging our species' survival odds upwards over the long haul (Long Now Foundation, millennia to millions of years scale).
isn't the likelihood of a cascade very low because of the orbit thing?
I.e. object X hits Y, they both spin out of control but most likely they will either go towards earth or go away from it, so they chance of them hitting something else is very limited, it's not like billiard balls that would eventually hit each other.
> Even a fleck of shed paint a tenth of a millimeter across carries as much kinetic energy as a rifle bullet when it's traveling at orbital velocity,
Relative to an object stationary on the ground, yes. But every satellite is already moving at orbital velocity itself. If two satellites are orbiting in the same direction and one blows up, its pieces will not hit the other with full orbital velocity.
> any launch at all becomes a game of Russian roulette.
Maybe if the situation gets this bad, then the mitigation actually gets easier: just send up a lot of cheap big rockets on parabolic trajectories to orbital height. They will get hit, all the pieces will fall below orbital velocity, and fall down into the atmosphere. We could even launch cheap parabolic trajectory "blockers" to clear holes in the debris field for launches to higher orbits or escape trajectories.
Economics is usually more important factor than science. Science provides possibilities, economics selects those possibilities that are realized.
Instead of building those sci-fi space stations and exploring plants that has been scientific possibility for decades, we have realized and exceeded our sci-fi dreams in computers, internet and mobile phones.
If billion people spend $10 per month on something, there is economic incentive to spend billions in technological research.
This is what is assumed to have happened to STS-7 (Challenger, not fatal), check the photo of the impact crater in the window here:
https://en.wikipedia.org/wiki/Space_debris
A .44 Remington Magnum with a 240-grain (0.016 kg) ...(360m/s)
Which has 1036.8J of kinetic energy.
So the ratio is actually about 32400 in favor of the bullet. But note that this will change with the cube of the size mentioned, so even though this is exaggerated, a fleck of paint 3mm across would make the quote reasonably accurate.
On that subject, I recommend to read Spin by Robert Charles Wilson. It is not exactly a Kessler syndrome, but for some reason, one day a kind of dome/membrane encloses the Earth blocking communication with every satellite. (Physical objects can still go through as far as I recall, but since you can't communicate with them, it is not that interesting)
This is good sci-fi book who won the Hugo award about the societal impact (with somewhat weaker sequel, but still enjoyable in their own way)
[+] [-] lemevi|10 years ago|reply
I just don't have the capacity to be anxious every minute of my life for everything that could possibly go wrong for us someday in the future.
[+] [-] jfoutz|10 years ago|reply
Tech has done wonderful things to keep costs down, but it's a lot tougher to get that barrel of oil now days. I think there are, at least to some degree, costs being offset by increased risk. Deepwater horizon is a pretty obvious example. Groundwater contamination from fracking is another. I think the price per barrel has been on a steady downward trend, but I'd bet that including the environmental impact just from accessing (not burning) oil, we're paying more. I'm not aware of any such study.
In any case, we're the first, but also last technological civilization to use oil. If a wizard waved a magic wand, and we were suddenly sent back to a 1700's level of technology, i don't see how we'd be able to get much oil at all. It's not bubbling up out of the ground anywhere anymore. The easy stuff is gone. there's no way to get the hard stuff by hand.
[+] [-] ChuckMcM|10 years ago|reply
[+] [-] ctdonath|10 years ago|reply
At some point I looked at my own anxieties and simply decided to not be anxious: do what I could about what I could given resource (time included) constraints, be prepared for eventualities within reason, and otherwise carry on.
My biggest recurring concern now is how I'm not anxious. Should something horrible happen, I may be disconcertingly unconcerned - having done what I could in good faith, there is/was nothing else to do but accept reality and move on.
[+] [-] elipsey|10 years ago|reply
The Mathusian Catastrophe has also failed to fully materialize because people are not bacteria, and so we planned ahead and are trying to control population and improve agricultural efficeincey. Did we do a perfect job? No, but we did better than bacteria.
Just because a doomsday scenario fails to emerge does not mean the problems were completely bunk.
So I'm guessing Stross thinks we should imagine what will happen if we don't do something about Kessler Syndrome, and then become motivated to do something about it.
[+] [-] hellbanner|10 years ago|reply
[+] [-] javajosh|10 years ago|reply
So relax, and enjoy a good setting for a dystopian story.
[+] [-] clarkmoody|10 years ago|reply
Now: better modeling would probably help us determine whether Kessler syndrome will actually happen.
[+] [-] mdpopescu|10 years ago|reply
Lists like [1] remind me of my extremely scary youth :)
[1] http://wattsupwiththat.com/2013/01/19/great-moments-in-faile...
[+] [-] Symmetry|10 years ago|reply
Further out in MEO where GPS satellites are there's a much greater volume, fewer satellites, and the satellites aren't moving as fast. There's no way Kessler Syndrome is going to start there. You do have a bunch of Russian satellites that loop in fast and close by the South Pole then go high and slow over the North, letting them spend most of their time being visible from Russia. Debris from from a cascade could kill one of those, which would cause debris that would kill some but not all of the GPS sats. It would be a relatively slow process compared to what would go on in LEO, though.
Satellites in GEO won't need to worry about Kessler at all. They're all in equatorial orbits, traveling in the same direction at the same speed. If one explodes its debris will only hit other satellites with the explosion velocity, not orbital velocity. So those should survive Kessler Syndrome fine, though you can't put any new ones there.
Also, Kessler Syndrom isn't forever. Satellites in LEO need to boost every once in a while to overcome atmospheric drag. As things get broken up their surface area to volume ratio increases and the fall out of orbit faster. Air density falls of exponentially with height so the lower reaches of orbit will become safe first. The inner reaches of LEO might be clear quickly but I have no idea how long it would be before orbit was totally clear.
[+] [-] clarkmoody|10 years ago|reply
The approach has been to go after the large spent boosters (a few thousand of them), since they contain the most mass of any class of debris objects. Each upper-stage booster has a rocket nozzle that makes a great target for grappling.
As other comments have noted, the main issue is actually deciding to spend money bringing down orbital debris. As with many other issues we face, this is another case of kicking the can down the road, and we may not address it until the collision cascade has started :-/
[1] http://lasr.tamu.edu/research/proxops/#Debris_Removal
[+] [-] __d|10 years ago|reply
I'm hoping to see a cleanup driven by a desire to reclaim the constituent metals, etc, without a need to boost them out of the gravity well.
[+] [-] nabla9|10 years ago|reply
Interesting paper where supercomputer was used to simulate the increase of particles greater than 10 cm in size over 100 years with high temporal resolution.
Results for BAU (business and usual) and BAU-d business as usual with decreasing breakup rate don't look so good: "linear growth of the catalog size with time, to ~65,000 objects by year 2100." 100 years from now there will be 50 conjunctions per day and 3 collisions per year.
[+] [-] 27182818284|10 years ago|reply
[+] [-] aaronbrethorst|10 years ago|reply
[+] [-] fsiefken|10 years ago|reply
[+] [-] allencoin|10 years ago|reply
[+] [-] ble|10 years ago|reply
Additionally, a not-too-unreasonable interpretation of current international treaties would lead one to conclude that piece of junk, inoperable satellite X (or a piece of debris that comes off of it) is still owned by country Y, interfering with it is a violation of Y's sovereignty, etc. This is to be contrasted with the seas where there are some kind of established norms about the wreckage of ships, abandoned ships, etc.
I kinda want to bone up on the relevant treaties and/or agreements about Earth orbit and other planets.
[+] [-] clarkmoody|10 years ago|reply
Interesting to think about, but I have a feeling that once you land on another celestial body, all property will be determined by homestead until a significant number of humans arrive later.
Imagine: there you are on Mars, building your habitat structure in a nice crater when the phone rings and NASA says, "Hey, you can't build there, since that's Russia's crater." Your response should be, "Well, when Russia gets here, they can move me off of their property."
The ability to enforce property rights is vastly reduced without a local presence representing your interests. Yes, there could be conflict over it here on Earth, but for the people actually off-world, it has no actual enforcement mechanism, especially on one-way missions. Any such treaties and agreements made now are purely for show and political gain by those parties involved.
[+] [-] maxerickson|10 years ago|reply
[+] [-] jcromartie|10 years ago|reply
[+] [-] ceejayoz|10 years ago|reply
[+] [-] baq|10 years ago|reply
and that's basically the smallest accidental collision in space you can imagine (not counting failed berthings/dockings and the like).
[+] [-] Arnavion|10 years ago|reply
As the other comments mention, satellites also have different inclinations. Even a tiny difference of inclination projects a large speed on the axis along the two satellites, again due to the large speeds involved.
[+] [-] DonHopkins|10 years ago|reply
[+] [-] mark-r|10 years ago|reply
Edit: I just got dinged for this comment, if there's a flaw in my reasoning or a study that refutes it please let me know.
[+] [-] peeters|10 years ago|reply
True, but most of the other objects near it are also at or near orbital speed, so what's the kinetic energy when compared to an object it would actually be likely to hit?
(The situation in Gravity made no sense to me. The shuttle encounters the debris field every 90 minutes...why was that debris not also orbiting the earth with roughly the same period as the shuttle?)
Is the solution a matter of countries agreeing to "lanes" for orbits that differ non-trivially? (e.g. 300-330km is reserved for equatorial orbits, 340-360 km is reserved for polar orbits, 380-400km is reserved for retrograde orbits)
[+] [-] daenz|10 years ago|reply
[+] [-] outworlder|10 years ago|reply
Plans to colonize Mars and the like would have to be postponed.
Important satellites would have to hug Earth's atmosphere to stay (somewhat) safe. They could look somewhat like this: https://en.wikipedia.org/wiki/Gravity_Field_and_Steady-State...
More fiber optic cabling would be required. Local stations to retransmit information would have to be created (or existing infrastructure, such as cellphone towers, would be retrofitted).
And so on. We'd do fine, I guess. But not without an enormous cost.
[+] [-] rmc|10 years ago|reply
[+] [-] masklinn|10 years ago|reply
[+] [-] Terr_|10 years ago|reply
[+] [-] DanBC|10 years ago|reply
http://orbitaldebris.jsc.nasa.gov/
It has some nice photos of some of the impacts that spacecraft have had.
---
Reading cstross's post at a tangent: I'm interested in how viable it is for a well funded technological terror group (like Aum Shinrikyo used to be) or "rogue nation" to dump a few tons of sand and grit (or depleted uranium, for the mass) into the correct orbits.
[+] [-] yourapostasy|10 years ago|reply
http://www.antipope.org/charlie/blog-static/2010/08/space-ca...
http://www.antipope.org/charlie/blog-static/2007/06/the_high...
So a Kessler Cascade definitely sucks, but it isn't an "OMG, humanity loses its 'birthright to the stars'!" catastrophe because we can't GET to the stars for the foreseeable future, barring a Copernican-grade revolution in physics and accompanying engineering that opens a hitherto-unknown means of multiple magnitudes FTL transportation of the peta- to tetra-tons of mass associated with an en masse out-migration to the stars scenario.
This has interesting implications (I happen to strongly agree with his analysis) for how we set and carry out future policy, if you want to figure out means of nudging our species' survival odds upwards over the long haul (Long Now Foundation, millennia to millions of years scale).
[+] [-] riffraff|10 years ago|reply
[+] [-] snowwrestler|10 years ago|reply
Relative to an object stationary on the ground, yes. But every satellite is already moving at orbital velocity itself. If two satellites are orbiting in the same direction and one blows up, its pieces will not hit the other with full orbital velocity.
> any launch at all becomes a game of Russian roulette.
Maybe if the situation gets this bad, then the mitigation actually gets easier: just send up a lot of cheap big rockets on parabolic trajectories to orbital height. They will get hit, all the pieces will fall below orbital velocity, and fall down into the atmosphere. We could even launch cheap parabolic trajectory "blockers" to clear holes in the debris field for launches to higher orbits or escape trajectories.
[+] [-] applecore|10 years ago|reply
When did we become so pessimistic?
[+] [-] nabla9|10 years ago|reply
Instead of building those sci-fi space stations and exploring plants that has been scientific possibility for decades, we have realized and exceeded our sci-fi dreams in computers, internet and mobile phones.
If billion people spend $10 per month on something, there is economic incentive to spend billions in technological research.
[+] [-] kohanz|10 years ago|reply
[+] [-] creshal|10 years ago|reply
But who will pay for it?
[+] [-] DarkTree|10 years ago|reply
Just wow.
[+] [-] theandrewbailey|10 years ago|reply
[+] [-] chrisBob|10 years ago|reply
[+] [-] fsiefken|10 years ago|reply
[+] [-] 19870213|10 years ago|reply
[+] [-] Jabbles|10 years ago|reply
Volume = 1e-4 ^ 3 = 1e-12 m^3 Assume density 1kg/l Mass = 1e-9kg Velocity = 8000m/s KE = 0.032J
Mass of bullet (https://en.wikipedia.org/wiki/Physics_of_firearms)
A .44 Remington Magnum with a 240-grain (0.016 kg) ...(360m/s)
Which has 1036.8J of kinetic energy.
So the ratio is actually about 32400 in favor of the bullet. But note that this will change with the cube of the size mentioned, so even though this is exaggerated, a fleck of paint 3mm across would make the quote reasonably accurate.
[+] [-] seren|10 years ago|reply
This is good sci-fi book who won the Hugo award about the societal impact (with somewhat weaker sequel, but still enjoyable in their own way)
[+] [-] emilburzo|10 years ago|reply
[+] [-] brickmort|10 years ago|reply
[+] [-] unknown|10 years ago|reply
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