
Bi-Directional Plasma Thrusters for Space Debris Removal - ArtWomb
https://www.nature.com/articles/s41598-018-32697-4
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aogl
Is it realistic to presume that space debris orbiting around the earth will
only ever get worse, or will it effectively remain the same to some degree of
consistency?

Or is it more of a thing that it only becomes more of a noticeable problem for
us as humans when we are affected. Meaning that the only reason we have a
problem with it now as opposed to some previous timespan is that we are
sending more and more objects/satellites/etc into orbit and they are being
damaged/destroyed/affected, so we therefore write about it and try and come up
with ways to stop it?

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panzagl
Most of the debris in orbit is a result of 2 events, one of which was a
purposeful action of the Chinese government. So if humanity can refrain from
blowing up satellites, or at least keep from blowing them up in the stupid way
the Chinese did, it should remain manageable.

Of course, some of the most difficult to track debris was put up there in the
name of science- the Telford needles, pieces of tether, and shreds of solar
sails. If the big net experiment from a couple of weeks ago had gone awry,
we'd have another difficult to track fabric-like bit of junk shredding itself
into smaller yet still dangerous pieces up there.

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A2017U1
Was a bit sceptical at first but this seems fairly correct. There's been
numerous collision events, only one stands out as intentional and of greater
magnitude than all the rest. I do wonder how future generations will judge
such actions given the difficulty of clean up and general world consensus to
not militarise space.

[https://en.wikipedia.org/wiki/List_of_space_debris_producing...](https://en.wikipedia.org/wiki/List_of_space_debris_producing_events)

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Nomentatus
Something I proposed and sent to the experts many years ago; back then I was
thinking of opposing ion rather than plasma engines of course. Plasma wasn't a
thing, then.

A point they've dropped from my proposal is that used on a spinning target you
can de-spin it. (Even if it's spinning along more than one axis in fact, with
intermittent thrust.) This is especially useful to capture, move, and then
utilize asteriods, say. Or as a way to stabilize the target (such as an
asteroid), so that both engines can be joined to the target to move it. See
"jacknife" below.

Very useful for cleaning debris from orbit.

A few years ago, I realized that what you want is a "jackknife" implementation
with a hinge between the two engines that allows you to use both thrusters to
move to and from the objects you want to move. Since no-one had picked up the
original idea (except as modified to use gravity vs one engine), I made no
attempt to publicize that refinement to the idea.

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mr_overalls
Just out of curiosity, why didn't you apply for a patent?

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Nomentatus
Ill and therefore poor. Not the only famous idea I could have patented. I
could take out a couple of hundred patents now, still, if I had the money.

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aaronchall
Given the rate at which our patent offices hand them out, there's no doubt any
one of us could take out a couple of hundred patents if we had the disposable
money to apply for them.

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Nomentatus
True! But I did mean wholly legitimate patents of useful novel ideas.

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seymour333
Ooh, what about a laser on the space side of the debris that heats it, causing
the release of gases that propel it towards earth? You would have to be able
dynamically re-target the debris for uniform acceleration while also pulsing
the laser if the debris is spinning, but it would probably work.

soure: I can't even do basic math, but maybe someone smart will think this is
an interesting idea

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simonh
It might be better to just shine a bright laser on it for an extended period
of time and let light pressure do the job.

Side not, you would do this to the 'front' of the satellite as it orbits - the
bit facing in the direction of travel. This would slow it down and make it
fall into progressively lower orbits until atmospheric braking took over.

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delibes
Somewhat inspired by the Japanese robots bouncing around on the Hayabusa2
mission ... I think it'd be nice to be able to 'push off' against the debris
satellite, to both decelerate it whilst also gaining orbital velocity for the
clean-up satellite to go hunt down another target.

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simonh
If you push off against it to gain velocity, you'll fly away from it very
quickly and not spend long enough pushing it to meaningfully change it's
orbit.

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xelxebar
It might be concievable to bounce lased light back and forth for a while and
transfer momentum that way.

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nategri
Is anyone else thinking of "the Kzinti lesson" from the Known Space books?

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carapace
The idea of waste or debris in space is simply wrong.

It's a bit of flatlander nonsense that should not be brought off the surface.
I was shocked as hell when I found out astronauts vent trash and waste.

"Come, let us reason together."

There are not a lot of atoms in space, by definition, compared to terrestrial
conditions. (Okay, technically _all_ atoms are in space. You know what I mean.
;-P ) So, if you have some atoms together in space already it's just stupid to
disperse them into small bundles and then lose track of their orbit. (You _can
't_ throw things away in space, you can only lose track of them. They'll be
back.)

It takes a lot of energy to get a bunch of atoms to orbit from the surface.
It's wasteful to discard "waste"! (Say it with me, "No waste in space!")
Literally, in space, matter is only "waste" because you let go of it and
stopped paying attention to it. _It 's still useful, just not to you right
now_. Even if you're sure you'll never have a use for it, it's criminally
irresponsible to "throw away" matter in space. It's like firing a gun into the
air: that bullet is coming down somewhere... At the very least bundle it up
and tag it with a radar reflector or something.

In conclusion, space is big and empty and curved, atoms are rare, important,
useful, and expensive to bring with you. _Keep them nearby and on stable
orbits._ That way you don't have to waste energy collecting them again _and_
they aren't rattling around forming a collision lottery in LEO.

No waste in space.

\- - - -

Now then, as a bit of a tangent, are you familiar with the "spittlebug",
_Cercopoidea_? Their nymphs form nests of bubbles that look like little blobs
of spittle. I say this is the correct design for space vehicles and stations.
Spittlebug nest. Not metal can. Cheap, simple, ridiculously easy construction
methods, durable, self-repairing, reusable, flexible, etc... I'm sure we could
make materials that permitted different kinds of bubble, for e.g. storage,
blocking radiation, absorbing collision energy, etc...

So, build your space stations out of bubbles. If you do it right you can
collect debris for free. (Hint: you have to intersperse threads with your
bubbles and have the right kinds of glue and stick'um. It's all down to
materials science at this point, the spittlebug design doesn't really have any
other constraints. You could make a space vehicle that "landed" by simply
crashing. Density of the atmosphere and the vehicle would determine velocity
at touch down. Or, you just make the bubble nest really big. Like 10K
diameter. Then when you "crash" your core ship (which actually might be a
metal can) settles to the ground through ~5k of bubblewrap.

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Hupriene
The space stations we've built have all been in LEO. The ISS would deorbit in
less than two years without periodic boosts. As such, no nearby orbit can be
considered stable. The fuel required for boost is proportional to its mass. So
it's quite reasonable for space programs to cast of 'dead weight' that doesn't
contribute to the mission of the space station.

