Kessler Syndrome - We almost lost the ability to leave Earth a little over two weeks ago.

[Leo S]

Here's another thread to brighten up the weekend - sorry!

While there are many threats to our existence here on Earth, this one has the potential to compound our problems, especially if in combination with another threat (eg. large asteroid discovered on a collision course).

So a little over two weeks ago there was a near miss in orbit between two satellites in orbit - literally a few feet, which is like missing by a hair's width relatively speaking. Had they collided there would now be a cloud of debris - deadly missiles traveling at thousands of miles per hour, and it's possible that they in turn would collide with other satellites in orbit, creating a chain reaction/positive feedback loop where the debris field expands out of control, potentially trapping us here on Earth. That is the Kessler Syndrome.

No one seems to be paying attention, and yet again we seem to be sleepwalking into big trouble. Russia is the worst offender, but the likes of Musk are not helping either. Of course we need satellites, but it's like the wild west up there right now - sigh!

[saac]

Wouldn't the orbit of these eventually decay ?

Jim

[ONIKKINEN]

2 minutes ago, saac said:

Wouldn't the orbit of these eventually decay ?

Jim

Decay due to drag is painfully slow above a certain altitude, maybe 500km+ (of course depends on the density of the object, light debris will fall faster). Will take decades at least, and for objects at 1000km+ it would take so long that the people of today might as well call it permanent.

But i think the whole Kessler syndrome thing is over-exaggerated, it wont stop our modern way of life with satellites and internet, it will just make it more costly to send new satellites out as in order for them to be at a safe altitude they need to be launched much higher, like where GPS satellites are today. That high there wont be a significant threat of space junk anymore and the satellites would survive as they do now. The extra cost might come from the fact that if its really bad at near earth orbits there might be a high chance of impact during launch so a lost vehicle every now and then but eventually one launch will succeed and then the satellite will work for several decades afterwards. Human spaceflight would end, but we dont really need it at all in my opinion.

[900SL]

We do, as a species, seem unable to stop fouling our little nest

[saac]

So in a few hundred years the debris field will most probably be sufficiently clear.  In any respect, I wonder that if the density of orbital "rubbish" is sufficiently high then it would raise commercial pressure to develop and employ clearance measures.  To date, we have experimented with deorbiting and recovery technology, but if in the future the commercial reward is raised then we would see this activity accelerate.

Jim 

[Leo S]

4 minutes ago, saac said:

So in a few hundred years the debris field will most probably be sufficiently clear. 

That's if we don't send more junk up there/stop conducting anti-sat tests and the like, ie throwing more fuel on the fire. But at the moment, that is not the case, although they are trying to figure out ways to remove junk from orbit. When the junk breaks down/becomes small it becomes harder to do though.

[900SL]

Giant space magnets and hoovers!

How do you catch a million speeding bullets?

[Leo S]

It's certainly not easy. Lasers to vaporize them perhaps, or big sheets of kevlar like material. Much of the debris cloud would likely be going in the same direction, so perhaps a barrier in it's path could neutralize hundreds of small fragments in one go.

Just as an aside, if any of you have seen the film "Gravity", that is based on the Kessler Syndrome. I thought is was quite good, and they made an effort to get the physics right, unlike many films.

[ONIKKINEN]

Whatever clearing method of the eventual debris is developed, it better be earth based or at most upper atmosphere based so that we dont add more debris up there.

I like the idea of lasers. Maybe mount one on a hypersonic aircraft flying in the very upper atmosphere and vaporize the bigger pieces? Or, launch the junk-zapper into a medium earth orbit where it is safe from debris and shoot downwards towards the limb of the earth so that the beam doesn't actually make it to the surface.

[saac]

Vaporise them with low yield nuclear bombs; it will have the added bonus of getting rid of them. It's what they would do in the movies - job done. 

Jim 

Edited February 13, 2023 by saac