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Kessler Syndrome

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Re: Kessler Syndrome

#41

Post by ryandrake »

JshWright wrote: post #20
mabbo wrote: post #17

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 "…

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)

Presumably, with OP’s plan, when you deorbit your own satellite you get your deposit back.

Re: Kessler Syndrome

#42

Post by Diederich »

ogre_magi wrote: post #40
danielvf wrote: post #28

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 satel…

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…

https://en.wikipedia.org/wiki/Gravity_(2013_film) doesn't help matters, though I did enjoy watching it overall.

Re: Kessler Syndrome

#43

Post by CompelTechnic »

danielvf wrote: post #28

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 satel…

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.

Re: Kessler Syndrome

#44

Post by tfha »

danielvf wrote: post #28

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 satel…

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.

Re: Kessler Syndrome

#45

Post by dr_orpheus »

mabbo wrote: post #17

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 "…

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.

Re: Kessler Syndrome

#46

Post by Namari »

7000skeletons wrote: post #25

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.

Didn't read the manga but the anime was pretty good.

Re: Kessler Syndrome

#47

Post by danielvf »

tfha wrote: post #44
danielvf wrote: post #28

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 satel…

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 thi…

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.

And that’s with a magical worst case.

Re: Kessler Syndrome

#48

Post by nwah1 »

danielvf wrote: post #28

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 satel…

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.

Re: Kessler Syndrome

#49

Post by ogre_magi »

nwah1 wrote: post #48
danielvf wrote: post #28

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 satel…

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.

You have no idea what you're talking about.

Those thousands of satellites will be in very low orbits, they will be well-tracked, and will not cause any issues for space access.

Re: Kessler Syndrome

#50

Post by ogre_magi »

CompelTechnic wrote: post #43
danielvf wrote: post #28

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 satel…

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 secr…

>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.

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