Stark wrote:Maybe - just maybe - the OP with the words 'self-sustaining' in it? Nobody else has used this phrase.
The OP appears to have assumed that everyone here knows about the Kessler Syndrome, shown by his saying 'Yes, THAT Kessler'. I'm guessing you haven't come across it before.
The Kessler syndrome (also called the Kessler effect, collisional cascading or ablation cascade), proposed by NASA scientist Donald J. Kessler in 1978, is a scenario in which the density of objects in low Earth orbit (LEO) is high enough that collisions between objects could cause a cascade – each collision generating debris which increases the likelihood of further collisions. One implication is that the distribution of debris in orbit could render space exploration, and even the use of satellites, unfeasible for many generations.
[...]
The Kessler Syndrome is especially insidious because of the "domino effect" and "feedback runaway". Any impact between two objects of sizable mass spalls off shrapnel debris from the force of collision. Each piece of shrapnel now has the potential to cause further damage, creating even more space debris. With a large enough collision or explosion (such as one between a space station and a defunct satellite, or the result of hostile actions in space), the amount of cascading debris could be enough to render low Earth orbit essentially impassable.[4][5]
So whether you want to say 'self-sustaining', 'cascading', 'runaway', 'domino effect', or 'metastable transition', the basic idea is the same. 'Many big things whizzing around in orbit' is a metastable state. The idea is that, if pushed far enough, the system will shift into a different equilibrium - one of 'many, many small things whizzing around in orbit'. This has the side effect of supposedly destroying all current satellites and making it impossible for humanity to leave Earth. That is, until space is cleaned up somehow, at enormous cost.
So the main idea has been to ensure that such a transition does not occur, by limiting addition of new space debris and trying to deorbit existing debris. It's easier to use a laser to bring down debris while it's still in one big piece, rather than in the form of billions of sand or dust-sized particles spread out over billions of cubic kilometres.
Link wrote:Space may need a clean up
Space junk has made such a mess of the Earth's orbit that it may soon need cleaning up, Nasa's former senior scientist has warned.
Donald Kessler said that might mean scooping up the debris with nets, magnets or giant umbrellas.
There are 22,000 objects in orbit that are big enough for officials on the ground to track - and countless smaller ones that could damage spaceships and satellites.
The International Space Station has even had to move out of the way of debris from time to time.
'We've lost control of the environment,' said Mr Kessler, who produced a report for the National Academy Of Sciences.
Since the space age began 54 years ago, civilisation has littered the area just above Earth's atmosphere.
The debris includes leftover boosters and other parts that come off during launches, as well as old satellites.
When scientists first noticed this could be a problem, they came up with agreements to limit new space junk - and those plans had been working.
The agreements are intended to make sure that what is now sent into orbit eventually falls back to Earth and burns up.
But Mr Kessler's report said two events in the past four years meant everything had now changed.
He said a Chinese anti-satellite weapon test in 2007 and the crash of two satellites in 2009 had put a large amount of new junk in space.
The widely criticised Chinese test used a missile to smash an old weather satellite into 150,000 pieces of debris.
Some 3,118 pieces of those pieces are large enough to be tracked by radar on the ground.
'Those two single events doubled the amount of fragments in Earth orbit and completely wiped out what we had done in the last 25 years,' Mr Kessler complained.
The study referred to a report by the Defence Advanced Research Projects Agency which mentions harpoons and nets as ways of sweeping up debris.
The report also referred to magnets and a giant dish or umbrella-shaped device.
Nasa officials said they were examining the study.
When scientists first noticed this could be a problem, they came up with agreements to limit new space junk - and those plans had been working. [...]
But Mr Kessler's report said two events in the past four years meant everything had now changed. [...]
'Those two single events doubled the amount of fragments in Earth orbit and completely wiped out what we had done in the last 25 years,' Mr Kessler complained.
It's a good thing the world's major economies have the surplus strength needed to fund space megaprojects, and that the biggest countries in the world are highly co-operative and have the political will and organisation needed to solve the big problems, well before there is an obvious, pressing need. The general public is very interested in space science, and very familiar with this problem and its effects, so I'm sure we'll have thousands of gigantic robotic magno-laser-umbrella-dish-net space stations up and running in no time.
