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Kessler Syndrome

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Re: Kessler Syndrome

#51

Post by ogre_magi »

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…

Dude, actually read.

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.

Re: Kessler Syndrome

#52

Post by js2 »

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…

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.)

Re: Kessler Syndrome

#53

Post by zbentley »

ogre_magi wrote: post #49
nwah1 wrote: post #48

Earlier quoted context omitted.

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.

> You have no idea what you're talking about.

That's not necessary.

Re: Kessler Syndrome

#54

Post by ogre_magi »

zbentley wrote: post #53
ogre_magi wrote: post #49

Earlier quoted context omitted.

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.

> You have no idea what you're talking about. That's not necessary.

Sorry -- people having very badly informed opinions about spaceflight are a pet peeve.

Apologies if I'm being rude. I'll stop commenting.

Re: Kessler Syndrome

#55

Post by 7000skeletons »

Namari wrote: post #46
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.

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.

Re: Kessler Syndrome

#56

Post by thinkcontext »

0xcafecafe wrote: post #19

I read about this first when I saw the movie "Gravity". I think if it really becomes that bad, given enough resources mankind can solve it.

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.

Re: Kessler Syndrome

#58

Post by stcredzero »

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…

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.

Re: Kessler Syndrome

#59

Post by stcredzero »

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…

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.

Re: Kessler Syndrome

#60

Post by stcredzero »

ogre_magi wrote: post #50
CompelTechnic wrote: post #43

Earlier quoted context omitted.

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.

How about a hundred BFR sized launchers? (Just scaling it up to nation-state/Bond villain levels, out of curiosity.)
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