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The sky's gone dark

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277 pointsandyjohnson0175 comments

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.

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.

I agree with you, but I think it is still important to be anxious and raise awareness of these problems. Without the panic, would Y2K have been "recognized as a solvable problem and solved"? We need to continue to raise awareness of these really big potential problems, even if we have confidence that they are solvable.

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.

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.

He is a sci-fi author, so his profession is to think of "what if"

As a sci-fi author, Stross is known for having a t-shirt that reads "I tell lies for money."

(One of multiple reasons that I'm a fan of his!)

Better to think about it and end up being wrong, than just having blind faith on Father Progress protecting us forever. Just because one Malthus was wrong once doesn't mean that no Malthus will ever be right.

The problem of progress is that by its own definition we can never be sure of what we are doing until we do it. Being cautious has to be an important virtue to keep in mind.

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.

I don't see this article, or these end of the world scenarios, as things you should be anxious about. Maybe some people suggest they are, but to me an article like this serves two purposes:

1. To remind people who are in positions to solve this problem that it is still a problem, by bringing attention to the issue.

2. To give an interesting example of an unexpected negative externality of a system as a case study, which might help me think differently about systems I create.

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.

I never was very intelligent, just smart enough to quote intelligent people, so I'll invoke Steven Pinker from his book 'The Better Angels of Our Nature':

Also distorting our sense of danger is our moral psychology. No one has ever recruited activists to a cause by announcing that things are getting better, and bearers of good news are often advised to keep their mouths shut lest they lull people into complacency. Also, a large swath of our intellectual culture is loath to admit that there could be anything good about civilization, modernity, and Western society.

Side note: peak oil is still very much a thing. Enhanced recovery and fracturing of source rocks bought us about another 15 years, but the Seneca cliff is still there.

It's also pretty much exactly as described. Light, sweet crude is gone and we can't sustain low oil prices (the current dip notwithstanding). Oil costs 5X what it did in the 90s. We are forced to use dirtier, more expensive types of oil. Economies suffer as a result. Peak oil happened as advertised.

Except that it did not happen as advertised. Peak oil was advertised as "running out of oil period," not "running out of easy-to-access oil." The problem is that for as long as we have been using oil, we have been running out of easy-to-access oil. U.S. production started in Pennsylvania and moved to Ohio. That was the easy-to-access oil in the late 1800s, early 1900s.

After Ohio and Pennsylvania, oil production shifted to Texas and California and then, when people found it tougher to find oil onshore they tried offshore.

There is nothing different with newer technologies like hydraulic fracturing, directional drilling, and advanced imagine.

We aren't at peak oil because extracting oil always has been heavily dependent on technology.

Here's what the peak oil chart for the U.S. looks like today: https://en.wikipedia.org/wiki/Peak_oil#/media/File:Hubbert_U...

> Except that it did not happen as advertised. Peak oil was advertised as "running out of oil period," not "running out of easy-to-access oil."

That's false. There may have been a few tin foilers who didn't read the source material and thus came away with the wrong scenario, but _peak_ oil by definition has always been about production peaking, based on the cost of extraction.

> Except that it did not happen as advertised. Peak oil was advertised as "running out of oil period," not "running out of easy-to-access oil."

Some people have misinterpreted that way, but they are people who didn't understand the basic underlying theory. Peak oil is a production peak driven by running out of cheap-to-extract reserves faster than technology reduces extraction costs, such that the amount of the resource that can be profitably extracted with available technology drops.

It is very different from resource depletion, e.g., running out of all of the underlying resource.

All these wells waiting for the price to rise will produce if supply decreases. What is the problem?

The price keeps rising?

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.

Other than the fact that there isn't evidence of fracking contaminating groundwater...

huh. weird. I thought it was known to be happening, but not yet widespread.

http://ofmpub.epa.gov/eims/eimscomm.getfile?p_download_id=52... "We did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States. Of the potential mechanisms identified in this report, we found specific instances where one or more mechanisms led to impacts on drinking water resources, including contamination of drinking water wells. The number of identified cases, however, was small compared to the number of hydraulically fractured wells. "

Also the sort of vague claim with no support that "well it hasn't happened yet" is kind of annoying. Nothing is zero risk. we can argue about p(bad_things) <.001 or .1 or whatever, but i think it's foolish to just pretend everything will be sunshine and rainbows forever.

I actually asked a family member who is an ecologically minded geologist about this (while we were at Yellowstone, no less). He said the primary issues now are twofold.

1) Law relating to public land use is terrible and biases insanely in the way of leasing for exploitation. In that the government is both required by law to lease and that the price is far shy of what a market would support (as it hasn't been updated in decades)

2) Inspection and fining of terrestrial operations is typically more self-reported (though only necessary if "sufficient" oil / chemicals have spilled). Measures are then put in place afterwards to monitor the well / location.

Admittedly, he wasn't in legal, but thought I'd share. Also, have to put a plug, if anyone has a lead on good-conscience geology jobs looking for someone with a BSc, I'd be thrilled to forward you on to him (contact me at {username}.co at gmail). He could have made easy money working in petrogeology but felt that wasn't something he could support.

When we were signing up for fracking under our land, we contacted the Ohio Dept of Natural Resources fellow who's responsible for tracking such things (groundwater contamination), and he said he had seen no evidence in 30 years of drilling (including recent) fracking. That's a pretty strong statement from the person whom you'd assume feels responsible for environmental protection

> That's a pretty strong statement from the person whom you'd assume feels responsible for environmental protection

Heh. https://en.wikipedia.org/wiki/Regulatory_capture and https://en.wikipedia.org/wiki/Revolving_door_(politics)

I'd expect them to be made up of folks with cozy ties to industry, just like the Federal version: https://en.wikipedia.org/wiki/Minerals_Management_Service#Gi...

As I said, he'd been there 30 years. If that's a revolving door, it ain't spinnin' very fast.

I'm as cynical as anyone, but in this case I don't think it's warranted.

http://www.pnas.org/content/112/20/6325.abstract

It has been proven that it does contaminate. That also doesn't consider the pools of wastewater on the surface. There are peer reviewed studies out there that state the evidence. Sadly, there is also a lot of misinformation being pushed by the oil and gas industry.

http://www.greenpeace.org/usa/new-science-shows-fracking-con...

Peak oil is here, and have been for more than 10 years. Yet, a phrase like this would sound impossible 15 years ago.

It's not that peak oil didn't happen, or that it wasn't traumatic. It did come, just like predicted, and we are on the way to adjust from a growth based society to a society where "if we work hard and right, we can improve the world!", and the transition has been traumatic, just like predicted.

Where predictions failed was that people expected a one in a 1000 years calamity (because it is a one in a 1000 years event), instead we got what looks like just a one in 100 years calamity.

>It's not that peak oil didn't happen, or that it wasn't traumatic

What trauma do you mean?

Something like this? http://twincharts.com/dow-jones-oil.html

I'm pretty sure at least some future economic historians will argue that what really killed the economy in 2008 was the "superspike" in energy prices.

You may not have noticed, but about the entire world has stopped growing by now.

Everything looks like growth will resume, but in a different way, and conditioned to a different social organization.

That's not because of high oil prices, it's because of financial chaos and general market turmoil. The oil boom across the Dakotas collapsed, but not because of lack of oil....?

> and the transition has been traumatic, just like predicted.

What trauma? What transition?

We currently have more oil than we know what to do with. It's piling up in huge storage containers, and the price keeps falling because no one needs any.

"The Stone Age came to an end not for a lack of stones and the oil age will end, but not for a lack of oil."

– Ahmed Zaki Yamani (Saudi & OPEC Minister for Oil)

I think oil is just one of those resources that we're never going to have to worry about. We've got two things going for us these days - first, the majority of oil production goes to powering cars which are becoming increasingly efficient, and, second the technology for extracting oil is also becoming more efficient. Fracking techniques right now only recover a small percentage of the actual oil that's in place - as those techniques are optimized, recovery rates will go through the roof.

I think we'll be way past the need for oil, long before we run out of it.

> I think we'll be way past the need for oil, long before we run out of it.

Oil isn't just used for fuel. What will replace the oil products in pharma, plastics, etc?

Plastics are probably the largest semi-direct user of hydrocarbons other than energy production, and according to the US Energy Information Administration [1] plastics used the equivalent of 2.7% of the total oil consumption in the US in 2010.

If we just stop burning the stuff we'll have enough for other uses for a very very long time.

We can synthetize all petroleum products from carbon feedstocks, so long as we can pay the energy cost. This is generally true of almost everything these days -- all resources that the modern economy depends on are substitutable or synthetizable with energy.

You can't spray your fields with efficient cars.

Watch me

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 :)

[1] http://wattsupwiththat.com/2013/01/19/great-moments-in-faile...

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.

Came here to say the same thing. Will also add: If LEO does get polluted, there are options to put (more expensive) satellites into MEO. At this point, it becomes an economic argument to "clean" or "push upwards"

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 :-/

[1] http://lasr.tamu.edu/research/proxops/#Debris_Removal

Having expended vast amounts of energy to get it up there, it seems a shame to bring it back down again.

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.

BRUTE FORCE MODELING OF THE KESSLER SYNDROME, Lawrence Livermore National Laboratory http://www.amostech.com/TechnicalPapers/2012/Orbital_Debris/...

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.

I don't understand - what's the difference between a conjunction and a collision?

The words are self descriptive:

Collision = con + laedere = strike together (two things strike each other)

Conjunction = con + iungere = join together (two things become joined to each other)

Conjuctions are when the objects are within a certain distance (basically a safety margin, usually several kms), a collision is an actual strike.

Conjunction is close approach between two orbiting objects.

Satellites may have to execute collision avoidance maneuvers and burn expensive fuel resources if the predicted trajectory brings debris too close for comfort.

If you would like to read a highly entertaining science-fiction novel about the stars going out, I couldn't recommend http://www.amazon.com/Spin-Robert-Charles-Wilson/dp/07653482... enough.

That does seem like an entertaining read; thanks for the recommendation.

Yeah, that was a great read even though it's not quite the same scenario :-)

Seveneves is a bit more similar to what the article describes. http://www.amazon.com/Seveneves-Novel-Neal-Stephenson/dp/006...

I definitely started recalling the White Sky scenario when reading this post.

And a great book in general.

Eh, I thought the last third was a letdown.

I agree. I still enjoyed the book though.

It probably is. Where Spin connects with the posting is more on what the planet does after the satellites fall and new industries for balloons, etc, form. I was on the fence about whether I should mention that or whether it is revealing.

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.

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.

> every one is OK with clearing it out.

Depends. Denying US access to any tech hurts them more than the armies that don't have such high tech capabilities. On the other side - if you US are mostly unaffected by that (preparations etc) they will be so far ahead that cleaning up the debris will hurt US superiority.

So - who will be ok with cleanup in that current moment can vary a lot.

To see a lot less serious mess unfolding in real time - Syria. While the end game is clear for all - get rid of ISIS and install strong stable government, everyone is moving to get advantage and increase its bargaining pool.

Everyone with space launch capabilities would be fine with it, and they are also the relevant parties when it comes to treaty issues. I don't think Russia and China would want to leave junk up there, I don't think any one else is even questionable.

I regret to say that when it comes to international negotiations, just because everybody is "OK" with something does not mean someone won't see an opportunity to make hay out of appearing to have a problem with it. They can hold out for money, use it as an opportunity to burnish nationalist credentials at home, any number of things.

What if your junk includes proprietary or classified technology? What if your nation state at one point put something into orbit that violated a treaty?

I'm sure there are a few reasons that relevant parties might not be totally cool with rival nations pulling their debris from orbit.

Yeah, except the ones that happen to be spy satellites under radio silence.

And when you refuse to clean a piece of "debris", everyone will know it's your spy-sat, so you (and everyone else) have all the incentives to deny cleaning things at random.

> 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 has no actual enforcement mechanism, especially on one-way missions

Could always send some weaponized rockets. They don't need to be there in person to enforce, I'd say.

(And I'm sure this violates a bunch of treaties but... eh.)

Also a very bad PR play, especially since there are no humans going to possess the property. It's just a rocket sent to blow up the trespassers.

You could depend on resources shipped from Earth which you won't get if you don't get off Russia's property, because the USA doesn't want to sour their diplomatic relations.

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.

The satellite that the US shot down was in a swiftly decaying orbit. That means that the periphrasis for all the debris was at least that far down and with the smaller ballistic coefficient of the debris it's all gone now.

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).

It's all moving in the same direction except for the British satellites, and satellites launched by some countries that used to be British colonies.

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.

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.

> 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)

I could imagine that the two orbits were inclined relative to each other. If the shuttle is orbiting around the equator and the debris field is orbiting from pole to pole then you would encounter it on every orbit. (Although then you would encounter it twice on each orbit...)

> 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?

If they're moving in opposite directions, then you just double it.

Actually, I think you quadruple it as kinetic energy goes as v^2.

If they orbit in opposite directions, the relative speed is twice the orbital speed. Low earth orbits go in all kinds of directions. In geostationary orbit everything is moving in more or less the same direction and speed.

I really didn't think there was that much variety in LEO due to the cost of launching in a retrograde orbit. I thought it'd be mainly prograde plus some normal velocity due to inclination.

The inclination matters, though. If something heading north at 41 degrees inclination meets something coming south at 41 degrees inclination, it's a serious collision.

(And, of course, every satellite has to spend half its orbit going north and half going south)

Retrograde orbits are uncommon as far as I know, but polar orbits are common for earth observation. A satellite going south could meet one going north.

Also unless you launch from the equator inclined orbits are cheaper to reach than equatorial. The ISS for example goes just far enough north to pass the Baikonur Cosmodrome.

If they are in opposite directions, they also will fail to cause Kessler Syndrome. If a satellite is hit by a debris with opposite velocity, it'll either fall down, or keep a similar but slightly lower and slightly mode dispersed orbit.

It's a 90° angle that is the worst.

The orbital mechanics in Gravity is simply wrong.

"340-360 km is reserved for polar orbits"

Consider a perfect polar orbit. At time 0, one satellite is above Yamagata heading due north , Japan and another is above Louisville, Kentucky, US also heading due north. These two satellites are on a (possible) collision course directly above the north pole, because all polar orbits go above the poles.

"Lanes" wouldn't work because of orbital decay. For example, the HST is ~550 km altitude. That's close enough that natural atmospheric reentry would happen in about 20 years. If that were to occur, it would descend through the lower 'lanes'.

Rather, it would only work if every satellite had active station keeping, had an active method to quickly deorbit, never failed, and never blew up (as DMSP-F13 is believed to have exploded due to a battery charging system - http://www.space.com/29996-us-military-satellite-explosion-d... ).

But if those assumptions are assumed, then we wouldn't have collisions in the first place.

Thanks for the response; great points!

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.

Hypervelocity is very high velocity, approximately over 3,000 meters per second (6,700 mph, 11,000 km/h, 10,000 ft/s, or Mach 8.8). In particular, hypervelocity is velocity so high that the strength of materials upon impact is very small compared to inertial stresses. Thus, even metals behave like fluids under hypervelocity impact.

https://en.wikipedia.org/wiki/Hypervelocity

The orbital velocity needed to maintain a stable low Earth orbit is about 7.8 km/s, but reduces with increased orbital altitude.

https://en.wikipedia.org/wiki/Low_Earth_orbit

We'd have to adapt.

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.

Neal Stephenson's latest novel, Seveneves, starts with essentially this premise, but with debris of the Moon.

The Planetes manga starts with space debris and the risk thereof, but terrorists outright attempting to trigger a Kessler event is a big subplot

There's an anime adaptation that's very well done. It explored the ideas of debris in space and clean-up efforts surrounding it pretty neatly.

Planetes is my favourite anime, though granted I haven't watched many.

I'm not sure if the logistics make sense though, I haven't done the math but I would imagine that the amount of fuel needed to change orbits would either be prohibitively expensive or you would spend months before returning to the base station.

I loved the anime. Very much a "slice of life" in the future that was wonderfully art directed.

Reminds me of the "Cowboy Bebop" universe, in which a large portion of the moon was shattered during an early test of hyperspace-gate technology.

NASA has an Orbital Debris website.

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.

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.

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).

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.

I assumed that if object Y hits object X it would result in a huge number of particles from the collision, each with a chance of hitting something else eventually.

Even if a single one of those particles hit one of our precious objects in the next 20 years it could be devastating.

But as it gets cheaper to put new satellites up, cleanup gets cheaper too. And if access gets cheap enough I could easily see an international treaty mandating that all satellites have an EOL burnup system installed. When 20kg costs $2mm a lot of people will balk at the idea. When 20kg costs $200k or $20k it's a lot easier to require people to include it. It could even be a bolt-on kind of thing, separately powered and controlled such that it doesn't have to be re-invented for every new satellite.

Also with access being cheap enough we could start doing active cleanup, beyond just not making the problem worse. Aerogel is supposed to be great for capturing particles because it's basically frozen air. We could build a space-based aerogel factory and ship silicon ingots up which then get turned into aerogel panels to be used as replenishable armor for the factory. And once you have the factory up you just start making the area that the armor sweeps bigger and bigger. Build out sideways to clear a particular orbit faster, build up or down to clear orbits of various heights. It'd be insanely expensive right now, but if launch costs come down to $100/kg or $10/kg it starts to look reasonable.

In 2007, the Chinese tested an anti satellite missile against a weather satellite.

The missile contained no explosives, it relied purely on kinetic energy.

The collision released 2,300 pieces of debris that were large enough to be tracked, so about golfball size or larger, and probably many times that number that are too small to track.

There's also a really, really large amount of space for maneuvering up there. Keep in mind the surface area of the sphere that's at 36,000 km from the ground (approx. average satellite orbit height) is ~22,567,880,697 km - that's entirely disregarding vertical room for maneuvering.

I am sure there are hot spots or rings of higher density corresponding to earth locations. Still, it's big.

> 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.

They aren't all moving in the same direction. Have a look: http://earthobservatory.nasa.gov/Features/OrbitsCatalog/

Do we really believe that science, if faced with the immense challenge of orbiting debris, won't find a way to regain access to orbit?

When did we become so pessimistic?

Of course we'll find a way.

But who will pay for it?

I think the point is that this problem is a lot easier to deal with before it is actually a problem. Reminds me of climate change, in that way.

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.

"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"

Just wow.

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

If you haven't seen the movie Gravity and the imagining of high velocity orbital space debris yet... go see it!

Low earth orbit is about 8km/sec. That means you could have a collision anywhere in the 0-16km/sec relative velocity range.

XKCD What if: https://what-if.xkcd.com/58/

"This means that if an astronaut on the ISS listens to I'm Gonna Be, in the time between the first beat of the song and the final lines ... they will have traveled just about exactly 1,000 miles."

https://www.google.com/webhp?q=1000%20miles%20%2F%208%20km%2...

WHOA

Not if it's a cube:

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.

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)

Webcache: http://webcache.googleusercontent.com/search?q=cache%3Awww.a...

thanks!

Future business opportunity: Space Garbage Reclamation. I'm only half-joking here, it would be a net benefit to anyone trying to put things into space by avoiding Kessler Syndrome and the junk itself could be valuable. Once we have space-based fabrication facilities, any materials that are already in space are much more valuable than those same materials on Earth.

I believe there's an Anime series around this idea:

https://en.wikipedia.org/wiki/Planetes

Space borne or even eventually ground base lasers could sweep the sky

If this comes to pass, Google's project Loon won't look so looney. http://www.wired.com/2014/06/google-balloons-year-later/

Unfortunately I don't think there's any feasible replacement for GPS satellites.

Ground stations can replace GPS. It might not be universal, but it for people inside a country it would work.

http://www.popsci.com/technology/article/2011-08/ground-base...

Perhaps it would be possible to do positioning from balloons that reference ground stations or stars. It would be more expensive than the current systems but cheaper than a fully ground based system.

I'm not read enough to understand exactly how the Kessler Syndrome scenario cstross proposes would interact with GPS, but significantly naval spending by the Superpowers is the big powers is the major effect I can easily see. When you have to protect undersea communication lines for military command and control (assuming the Kessler Syndrome would be a convenient way for hostile nations to launch attacks against other nation's orbital assets), meaning drone warfare becomes untenable outside a direct LOS engagement if undersea lines are not secured.

I also think there would be a major issue with weather satellites and prediction, causing a significant investment to be made in weather radar and alternative weather prediction and monitoring strategies.

> I'm not read enough to understand exactly how the Kessler Syndrome scenario cstross proposes would interact with GPS

GPS needs 24 satellites to function as planned. (It might work with less, but 12 seem to be the minimum under optimal conditions).

• If a Kessler cascade happens in the GPS satellites' orbits, it will rapidly disable existing GPS satellites, and deny access to said orbits for new satellites. Replacements could be launched into safe orbits, but this will likely take years, and those orbits will have a faster decay rate and less visibility (so you'd need even more satellites).

• A Kessler cascade in LEO will likely deny access to higher orbits, so while existing GPS satellites will continue to function, they cannot be feasibly replaced once their 10-30 years life span is exhausted.

I don't get how a Kessler cascade in LEO would deny access to higher orbits.

Can collisions become so common that staying in LEO for a fraction of a day is already dangerous? How many debris are we talking about here?

GPS is all in MEO rather than LEO. It's a larger volume with less stuff in it so there isn't much chance of getting Keller Syndrome up there.

And GPS one day may share MEO with power stations. They could use their lasers to target space junk, helping to turn it into less hazardous dust!

How does space debris reach a stable enough orbit that it doesn't just fall into the atmosphere and burn up? Also (maybe depending on the first question) wouldn't the chaotic nature of space debris collisions cause less stable orbits?

The debris doesn't have to reach stable orbits. The debris gets created in orbits that are already stable. It's also important to consider that stable in this context doesn't mean that the debris stays up there forever, it's just staying long enough to be a problem.

Some orbits are much higher than the atmosphere, so they are stable for a long time.

Why not just launch a big magnet into orbit and stick 'em all together?

EDIT: serious question

Couldn't researchers just adopt basic fission calculations to work for this application?

I mean its fundamentally the same problem. Large particles being impacted by smaller particles causing them to emit more smaller particles. I tried to work though this yesterday, but I'm not sure how to translate the free-space constant to orbital-scale units.

At the very minimum, the elasticity is completely different. Also, in one case particles are hold within a lattice, while on the other they are completely free to move in any direction. And there are orbits to think about, while on the other case the deciding factor is particles leaving the lattice...

Well, I don't think calculations would look any alike.

From the preservative of satellites (and items ejected from them) in the same orbit, they're motions are fixed to each other. They only appear in motion from a 3rd party observer on the ground, or in a different orbital.

I don't think the human beings will have no solution in hand for such a critical situation. Clearing up the debris to a good enough extent such that we can launch things normally won't be that hard at all, when hundreds of billions of dollars are at disposal. I'm not worried about this one.

I was just listening to a show about predictions of the end of the world (http://radiowest.kuer.org/post/latter-day-predictions), which seems appropriate. The sky is falling!

The problem is that the sky isn't falling! It's just... sitting there.

Basically, once we are done covering Earth in garbage we will make sure we do the same to the sky... How human!

Second Law of Thermodynamics, to call that "human" seems like unjustified exceptionalism.

Maybe filling our sky with junk will cancel out global warming? Yay humanity!

I guess all kinds of ways to handle it will appear if it is important enough, saying it will all go dark seems a bit too strong. Shielding. Special shapes to minimize impact. Smart avoidance movements. Continuous automatic cleanup of space debris. Etc...

If space debris can be detected and tracked, a fleet of garbage collector/deflector bots could clean the path in front of functioning satellites.

Though a giant block of expanding foam might be cheaper.

I feel pretty confident that navigation and communications would stay about the same, at least the social aspects pointed at in the question (different tech would be used, but so what).

Weather forecasting isn't all that important, warnings for hurricanes would probably be about the same. So there would be some inconveniences, but nothing huge.

The geopolitics is the interesting question. I wonder what sort of imaging capability could be attained by strapping systems to commercial flights and fiddling flight paths to increase coverage. That would require international cooperation, but maybe there's enough political will to make it happen.

> Weather forecasting isn't all that important

Unless you travel, use energy or eat food.

For travel, the local radar is more useful than a satellite picture or medium term forecast (where the sat data matters more).

For food, forecasting lowers production costs, but it isn't good enough that our agriculture actually hinges on it.

I realize my phrasing is blithe, but I simply don't see a lot of deep dependence on weather forecasts, they are used to good advantage, but would not be such a huge loss.

Local radar doesn't give IR, which among other things gives sea information. Quoting from https://en.wikipedia.org/wiki/Weather_satellite#Infrared_spe... :

> Infrared satellite imagery can be used effectively for tropical cyclones with a visible eye pattern, using the Dvorak technique, where the difference between the temperature of the warm eye and the surrounding cold cloud tops can be used to determine its intensity (colder cloud tops generally indicate a more intense storm).[10] Infrared pictures depict ocean eddies or vortices and map currents such as the Gulf Stream which are valuable to the shipping industry. Fishermen and farmers are interested in knowing land and water temperatures to protect their crops against frost or increase their catch from the sea. Even El Niño phenomena can be spotted.

Local radar doesn't give condition more than about 100 miles off-shore. It becomes more difficult to figure out if there's a front or severe storm coming to land. Consider, for example, a small typhoon somewhere in the Pacific. https://en.wikipedia.org/wiki/Cyclone_Tracy was spotted by weather satellite on 20 December but wasn't seen on radar until 22 December. It hit on 25 December. With weather satellites, it's easier to route shipping and flights around a disturbance.

Weather satellites are also used to identify new volcanic eruptions and route around their effects (http://www.sciencedaily.com/releases/2014/09/140926091334.ht...), and detect wind patterns over the ocean.

At some point it depends on what "deep dependence" means. It can easily be defined to make what you say be trivially true, and therefore uninteresting.

I would expect the volume of harvests to stay about the same, the number of fishermen to stay about the same and the number of flights to stay about the same.

There would likely be more lost crops and more accidents though (just not a huge percentage of lost crops or enough accidents to dissuade people).

I think you would like the conclusions from this paper - http://history.nasa.gov/sp4801-chapter13.pdf :

> the value of weather and climate information itself has been shown to be relatively small as a percentage of the economy.[33] However, when dealing with weather and climate where each year billions of dollars of property is damaged and many lives are lost as a result of severe weather events, even a small improvement in predictive capability can add up to major savings.[34]

Where [33] is "A good review of some of the economic issues in measuring the value of weather information can be found in Molly K. Macauley, “Some dimensions of the Value of Weather information: general principles and a taxonomy of empirical approaches,” http://sciencepolicy.Colorado.edu/socasp/weather1/macauley.h...

That affirms 'Most estimates of the value of [weather prediction] information suggest that it is not large as a percentage of final output.'

> Weather forecasting isn't all that important

Have you ever farmed? Or piloted a boat on a sea?

Civil aviation is a big user of weather forecasting too. Trans-ocean flights could get risky without it.

There is a difference between being very useful and being critical.

You list scenarios where good forecasts reduce risks, but the lack of them would not stop people farming or going out on the sea.

No, but it would make those activities more expensive and unpredictable.

I thought that was well implied by "reduce risks".

Okay, so these activities become drastically more expensive. That means that food is more expensive to grow, and to transport. This makes food from overseas harder to get.

(You might want to look at modern pea farming. I use peas because they don't seem like an exotic crop, but the process is pretty tech heavy. Peas are cheap (and fresh) because we have excellent short range weather forecasting.)

Your use of drastic and my dismissal of the problem look like competing opinions to me. I looked briefly for something about peas and didn't come up with anything, do you think a good discussion of the process would have clear information pointing to a drastic price increase?

On the bright side, imagine the orbital competitions that will result between megacorps and billionaires with space hotrods. Kessler Run, anybody?

Kessel run?

> Postulate a runaway Kessler syndrome kicks off around 2030, at a point when there are thousands of small comsats (and a couple of big space stations), ranging from very low orbits to a couple of thousand kilometers up. Human access to space is completely restricted; any launch at all becomes a game of Russian roulette.

Postulate? This article hasn't got a shred of calculation to give any hint when this becomes a problem. Is this a 2030 problem or a 2300 problem? No data.

It's a problem right now because we just don't know. It could happen tomorrow. It could happen in 2300. It's all chance. Like the example given of running across a field while machine guns blaze away. You might cross 100 times and be safe. I try to cross once and I'm gone. All we know is, our odds increase with each item we put in orbit.

Its measurable and predictable. A model has to be built is all. Nothing magical or unknowable about it. I agree with the idea that we should, fairly easily, be able to answer questions like "when will this become critical"

Further, its not a single happening - its a process modeled by a differential equation including terms for orbital decay, particle distribution over time, solar wind, new launches etc.

The author is trying to start a conversation about the societal implications, not trying to analyze the Kessler syndrome itself.

If it got bad couldn't we just send up a big cube of ballistics gel with some rockets and grab everything with that?

Not to be flippant, but I don't think that would scale well enough.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space." Douglas Adams, The Hitchhiker's Guide to the Galaxy

So a drone rocket that hovers around in orbit and shoots down debris sounds like another startup idea.

>There are some proposals to mitigate the risk of Kessler Syndrome by using microsats to recover and deorbit larger bits of debris, and lasers to evaporate smaller particles, but let's ignore these for now: whether or not they work, they don't work unless we start using them before Kessler syndrome kicks in.

Lol, ok then let's ignore proposed solutions.

The worst collision so far was deliberately caused by the Chinese military. Good job guys, way to show what a great country you are:

https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_mi...

You should read the parts where it says US has done similar tests and that "In response to US weaponisation of space, the Chinese started a space defense program, including anti-satellite defense."

That being said, this is a great example related to the OP (e.g. number and sizes of tracked debris and for how long they remain dangerous).

Eventually we'll have to use some combination of extreme ship armor (meter-thick plating of expired uranium?) and lasers that detect and zap all particles (that aren't human shaped) within 1 km of the spacecraft.

Boosting the kind of armor into orbit that would be necessary to deal with at least the worse scenarios is unfeasible. If you think that cost-to-orbit is high now...

True, and probably we'd have to either mine/manufacture the armor in space, or else develop some less expensive heavy lifting technologies (which is pretty much necessary anyway, if we're going to put up more manned space stations and interplanetary craft).

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