https://en.wikipedia.org/wiki/E.Deorbit: ”e.Deorbit is a planned European Space Agency active space debris removal mission developed as a part of their Clean Space initiative”
A valid example, but not quite a fair comparison. One of those happened in 2007 and the other happened more than 15 years before the idea of "Kessler syndrome" was even proposed.
There's no incentive to me to make my satellite safely de-orbit before it gets broken into pieces. So why would I bother? That's expensive.
But like all 'easy to litter, hard to clean up' problems of this nature, we have a solution already: require a cleanup deposit ahead of time that will be returned to whoever cleans it up.
All space-launching countries should sign an accord that said something along the lines of "Every satellite must have a deposit to the international Kessler Fund", say something like $X/kg, inflation adjusted. Companies would spring up with the sole purpose of de-orbiting defunct satellites. Launch would become more expensive, yes, but soon every bit of metal in space would come equipped with a plan for how we're getting it out of orbit.
This would work, but only if it allowed satellites to be exempted if they had a credible plan for deoribiting (which the vast majority of satellites launched today do, BTW). In that case, no one would actually pay the deposit, since it would cost several orders of magnitude more to go "get" a satellite (as opposed to just ensuring enough delta-V left over at the end of the mission to deorbit)
Not much need to worry about GEO. Everything there is moving at the same speed in the same direction. It's all the stuff in upper LEO where different satellites are all orbiting at different inclinations where this is a problem. And only upper LEO, down where the ISS is at ~400km an object with a low ballistic coefficient like a screw won't stay in orbit very long.
There are restrictions in place already to make sure that satellites launched now will de-orbit (or be placed in to a non-operational orbit). In order to get a license from the FCC to operate a satellite you have to prove that you have some way of de-orbiting the satellite within 25 years after mission end or 30 years from launch. On an international level the ITU has the same guidelines. This applies for satellites in low earth orbit.
For satellites in geosynchronous orbit it takes a hell of a lot of energy to de-orbit them. So the requirements are to place the satellite in a non-operational orbit at the end of the mission which usually means boosting it up higher outside of the geosynchronous belt.
It's a really hard problem. It costs over $100m to build and launch a spacecraft. Then the spacecraft has to catch up to the piece of junk, then do something to deal with the junk. We don't know what exactly it would do to deal with the junk.
Then the spacecraft would have to catch up to another piece of junk. That's hard because it's expensive in terms of fuel to change orbit. Thus the spacecraft would only be able to deal with a very limited number of pieces of junk before it ran out of fuel and became junk itself.
So, it would cost $millions per piece of junk. With hundreds of thousands now and millions in a Kessler scenarios it would be fiendishly expensive.
There's a pretty great manga series (and an anime adaptation, though it's not as good) called 'Planetes', that takes a pretty heavy focus on Kessler Syndrome and humanity's attempts to grapple with it in the near-future. Worth a read, if anyone's interested.
Honestly, I preferred the manga to the anime. Not to say that the latter is bad, by any stretch of the imagination, but it did get a bit wild and off-the-rails with it's final arc. The manga keeps things very grounded and existential. Anyone who's ever worked a shitty job for menial pay with no chance of advancement/further prospects will find something to relate to.
One mitigating factor is that Objects in LEO would Deorbit pretty fast. Usually in a matter of years. In higher orbits there’s a lot more space so it’s not quite as bad.
If a satellite is in a very low orbit then any debris fall to earth quickly. Almost all cubesats have a orbital life of six to five years. The space station, in a normal low earth orbit, would hit the earth in around three years without reboosts.
The higher you go, the more absolute volume there is, the slower the satellites there travel and the fewer satellites there are.
So that leaves a band of mid-upper LEO satellites to consider for Kessler Syndrome.
When you have a collision between satellites, the velocity on average of each fragment is less than it was before, making the fragments decay faster. The fragments after each collision are smaller than they were before as well, thus having more air and solar resistance, which also makes them decay faster.
The Chinese FY-1C satellite that was blown up was the absolute worst case for a satellite explosion. It was located on the high side of LEO with a decay time measured in human generations, and it was in a super crowded sun-following orbit altitude, sharing space with lots of weather and earth observation satellites. The explosion generated 150,000 debris fragments.
In the ten years since, most of those fragments have reentered. We now have 2,000 golfball sized or bigger fragments being tracked, and over the past ten years, the only casualty has been a small, ten pound reflector satellite. Small debris pieces fall, and big pieces can be tracked and avoided.
If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Space regulation has gotten much tougher since the bad old days. Satellites are now required to have deorbit or safeing plans, and the median satellites size has gone down by a couple orders of magnitude.
Kessler syndrome isn't something that keeps me up at night.
I see so many people around the Internet who smugly explain to their comments section of choice what Kessler Syndrome is, and link the Wikipedia page for it, and almost none of them actually know what they're talking about.
Whenever I bring up the density of debris in a given orbit, or the drag characteristics of the debris, they get mad. Everyone should read your comment and realize that it's possible to know a lot more about this than the Wikipedia article tells you, and accept that they are not a special enlightened environmentalist.
Kessler Syndrome is not a serious risk for Earth. It would be expensive and difficult to cause a long-lasting debris field that made space launches impossible on purpose. And we're trying to avoid it. Every organization with access to space is taking steps to mitigate space junk, including CNSA.
Whenever I bring up the density of debris in a given orbit, or the drag characteristics of the debris, they get mad.
That's kind of nuts. You'd think they'd feel relieved, like I just did when I read the top comment. It's like they want environmental disasters to be bad, like they have an ulterior motive.
I wonder how well the best designed intentional "Kessler weapon" could perform.
Some sort of large rocket that would fly to the right orbit height, and orient itself in a manner to ensure it's shaped charge explosives would send maximal debris (ball bearings of the right size) in directions azimuthal to the planet. How many satellites could you knock out if you really tried?
Quite an optimization problem for the secret skunkworks folks.
>How many satellites could you knock out if you really tried?
With a single launch scattering a lot of debris?
You could reliably take out ONE satellite. The clouds of debris creating a cascade of destruction as depicted in the movie Gravity are entirely fictional.
The easier and cheaper villainous way to deny spaceflight to someone is just to shoot missiles at their spacecraft.
Missiles can be pretty expensive, and if you go far downscale on cost and capabilities, you'll need to recruit fanatics who are willing to get caught every time a missile is fired at a spacecraft.
On the other hand, if the fleet of BFRs grows in numbers, then 100 flights of a BFR might be pretty inexpensive for a military operation that affects all strategic theaters at once.
The chief advantage of missiles, would be the ability to not shoot down your own rockets.
You make 1 in 1000 sound peachy. Imagine if you had a 1 in 1000 chance of collision every time your 747 crossed the ocean.
In 50 years I hope we are doing 50 space launches a day. At that volume, every single debris item is risk and headache. 10 years later and we've got a full 2,000 golf balls left in orbit? That's a lot. There have actually been casualties to blowing up the FY-1C? That's also significant.
These things get worse as we put more in space. If each explosion takes out on average 1 victim satellite per 5,000 satellites, and generates 1/100th the debris of the original explosion, we've got a cascade at just 500,000 total objects in orbit.
That may seem like a lot compared to the 5,000 we have today, but already we are discovering materials and technologies that are useful which can only be manufactured in free-fall. If orbital manufacturing ever takes off, 500,000 objects in orbit will be nothing.
The space shuttle had 135 flights, of which 2 were TPK’s. So a 1 in 68 chance of failure. And that’s on a man-rated launch system. The Russians have been having 1 in 10 to 1 in 20 non-human rated rockets failing. So even compared to our non-Kessler Syndrome world, a 1 in 1000 risk is almost insignificant.
However, what I’m really comparing it to is the popular perception - that Kessler means hundreds of years of humanity trapped on earth - In which case 999 non-issues in 1000 is fantastic.
>If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Sorry, but this is a pet peeve of mine. If you don't know anything about orbital mechanics or the fine details of spaceflight, don't smug about Kessler Syndrome. It's really vapid.
Kessler syndrome isn't an issue now, but as more projects like SpaceX's starlink program go online, it could become one. Starlink's goal is to deploy many thousands of satelites.
Yeah, starlink is planning on putting 8,000 satellites in low LEO, and 4000 in high LEO. The low ones don’t matter but the high ones are certainly worth thinking about.
IOW, "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."
(Sorry, I know this isn't a substantive reply but it's all I could think of reading your comment.)
If a satellite is in a very low orbit then any debris fall to earth quickly. Almost all cubesats have a orbital life of six to five years.
So then it should be possible to shift the world's global satellite infrastructure to low orbits, even if the unlikely worst case would happen. You wouldn't have geosynchronous satellites anymore, but we could work around that.
If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Much better odds than flying the Space Shuttle. Much worse odds than flying on an airline. That would still curtail civilization's expansion into space, though it wouldn't stop it.
Oh wow, is that where the term "Kessler Run" comes from in Star Wars?
If I recall, the Kessler run involved having to go through an asteroid field in the recent Solo movie.
For fans, you may recall that in the original Star Wars Han says: "You've never heard of the Millennium Falcon?…It's the ship that made the Kessler Run in less than twelve parsecs."
This got ridiculed because parsec is a unit of distance not time, but in the new movie they show that the run can be made longer or shorter.
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[ 0.18 ms ] story [ 134 ms ] threadhttps://en.wikipedia.org/wiki/RemoveDEBRIS: ”RemoveDEBRIS is a satellite research project intending to demonstrate various space debris removal technologies.
[…]
RemoveDEBRIS was launched aboard the SpaceX Dragon spacecraft on 2 April 2018
[…]
On 16 September 2018, it demonstrated its ability to use net to capture a deployed simulated target.”
Further, atmospheric drag keeps some orbits clear even in the worst case. The problem is you then need to constantly burn some fuel to maintain orbit.
* https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_mi...
https://en.wikipedia.org/wiki/Project_West_Ford
[1] https://en.wikipedia.org/wiki/Solwind
[2] https://en.wikipedia.org/wiki/Operation_Burnt_Frost
But like all 'easy to litter, hard to clean up' problems of this nature, we have a solution already: require a cleanup deposit ahead of time that will be returned to whoever cleans it up.
All space-launching countries should sign an accord that said something along the lines of "Every satellite must have a deposit to the international Kessler Fund", say something like $X/kg, inflation adjusted. Companies would spring up with the sole purpose of de-orbiting defunct satellites. Launch would become more expensive, yes, but soon every bit of metal in space would come equipped with a plan for how we're getting it out of orbit.
It won't cost the same to fetch something in low earth orbit than in geosynchronous orbit.
For satellites in geosynchronous orbit it takes a hell of a lot of energy to de-orbit them. So the requirements are to place the satellite in a non-operational orbit at the end of the mission which usually means boosting it up higher outside of the geosynchronous belt.
Then the spacecraft would have to catch up to another piece of junk. That's hard because it's expensive in terms of fuel to change orbit. Thus the spacecraft would only be able to deal with a very limited number of pieces of junk before it ran out of fuel and became junk itself.
So, it would cost $millions per piece of junk. With hundreds of thousands now and millions in a Kessler scenarios it would be fiendishly expensive.
So it’s kind of like we’re getting the effects of Kessler syndrome by trying to prevent it.
Food for thought.
The higher you go, the more absolute volume there is, the slower the satellites there travel and the fewer satellites there are.
So that leaves a band of mid-upper LEO satellites to consider for Kessler Syndrome.
When you have a collision between satellites, the velocity on average of each fragment is less than it was before, making the fragments decay faster. The fragments after each collision are smaller than they were before as well, thus having more air and solar resistance, which also makes them decay faster.
The Chinese FY-1C satellite that was blown up was the absolute worst case for a satellite explosion. It was located on the high side of LEO with a decay time measured in human generations, and it was in a super crowded sun-following orbit altitude, sharing space with lots of weather and earth observation satellites. The explosion generated 150,000 debris fragments.
In the ten years since, most of those fragments have reentered. We now have 2,000 golfball sized or bigger fragments being tracked, and over the past ten years, the only casualty has been a small, ten pound reflector satellite. Small debris pieces fall, and big pieces can be tracked and avoided.
If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Space regulation has gotten much tougher since the bad old days. Satellites are now required to have deorbit or safeing plans, and the median satellites size has gone down by a couple orders of magnitude.
Kessler syndrome isn't something that keeps me up at night.
Whenever I bring up the density of debris in a given orbit, or the drag characteristics of the debris, they get mad. Everyone should read your comment and realize that it's possible to know a lot more about this than the Wikipedia article tells you, and accept that they are not a special enlightened environmentalist.
Kessler Syndrome is not a serious risk for Earth. It would be expensive and difficult to cause a long-lasting debris field that made space launches impossible on purpose. And we're trying to avoid it. Every organization with access to space is taking steps to mitigate space junk, including CNSA.
That's kind of nuts. You'd think they'd feel relieved, like I just did when I read the top comment. It's like they want environmental disasters to be bad, like they have an ulterior motive.
Some sort of large rocket that would fly to the right orbit height, and orient itself in a manner to ensure it's shaped charge explosives would send maximal debris (ball bearings of the right size) in directions azimuthal to the planet. How many satellites could you knock out if you really tried?
Quite an optimization problem for the secret skunkworks folks.
With a single launch scattering a lot of debris?
You could reliably take out ONE satellite. The clouds of debris creating a cascade of destruction as depicted in the movie Gravity are entirely fictional.
Edit to add:
The easier and cheaper villainous way to deny spaceflight to someone is just to shoot missiles at their spacecraft.
Missiles can be pretty expensive, and if you go far downscale on cost and capabilities, you'll need to recruit fanatics who are willing to get caught every time a missile is fired at a spacecraft.
On the other hand, if the fleet of BFRs grows in numbers, then 100 flights of a BFR might be pretty inexpensive for a military operation that affects all strategic theaters at once.
The chief advantage of missiles, would be the ability to not shoot down your own rockets.
In 50 years I hope we are doing 50 space launches a day. At that volume, every single debris item is risk and headache. 10 years later and we've got a full 2,000 golf balls left in orbit? That's a lot. There have actually been casualties to blowing up the FY-1C? That's also significant.
These things get worse as we put more in space. If each explosion takes out on average 1 victim satellite per 5,000 satellites, and generates 1/100th the debris of the original explosion, we've got a cascade at just 500,000 total objects in orbit.
That may seem like a lot compared to the 5,000 we have today, but already we are discovering materials and technologies that are useful which can only be manufactured in free-fall. If orbital manufacturing ever takes off, 500,000 objects in orbit will be nothing.
However, what I’m really comparing it to is the popular perception - that Kessler means hundreds of years of humanity trapped on earth - In which case 999 non-issues in 1000 is fantastic.
And that’s with a magical worst case.
He said:
>If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Sorry, but this is a pet peeve of mine. If you don't know anything about orbital mechanics or the fine details of spaceflight, don't smug about Kessler Syndrome. It's really vapid.
Those thousands of satellites will be in very low orbits, they will be well-tracked, and will not cause any issues for space access.
That's not necessary.
Apologies if I'm being rude. I'll stop commenting.
https://news.ycombinator.com/newsguidelines.html
(Sorry, I know this isn't a substantive reply but it's all I could think of reading your comment.)
So then it should be possible to shift the world's global satellite infrastructure to low orbits, even if the unlikely worst case would happen. You wouldn't have geosynchronous satellites anymore, but we could work around that.
If every satellite we have put into space magically exploded, and the debris was magically moved to a high LEO altitude and evenly distributed to avoid any holes, then we could still launch through this orbit of death to higher altitudes with only a 1 in 1000 probability of impact.
Much better odds than flying the Space Shuttle. Much worse odds than flying on an airline. That would still curtail civilization's expansion into space, though it wouldn't stop it.
If I recall, the Kessler run involved having to go through an asteroid field in the recent Solo movie.
For fans, you may recall that in the original Star Wars Han says: "You've never heard of the Millennium Falcon?…It's the ship that made the Kessler Run in less than twelve parsecs."
This got ridiculed because parsec is a unit of distance not time, but in the new movie they show that the run can be made longer or shorter.
I know they retconned it. Now they need to retcon the name so that it is really Kessl run, short for Kessler.
Something I suppose we assume "space people" can deal with.
My suggestion: a space catapult (using a spring, not a weight).