Space Debris Removal

[belovelife]

at the current strongest electro-magnets we have, what would be the orbits and distances needed to

manuver a cleanup orbiter

 

what i mean is, if we could have 3 different altitudes and multiple sattelites pwered by solar power

 

with an on boeard electromagnet on the debris collecter

 

what is the minimal amount of sattelites needed to be able to manuipulate a satelite in orbit,

 

and change its vector in a predictable fashon

 

would it be worth trying to design a system

[belovelife]

or is it not possible to get electromagnetic fields with our technology, large enough to do such a thing

[blamski]

magnets would only work up to a point though. the majority of satellite material (which without further research i'm guessing makes up the vast majority of space junk) is aluminium, titanium and composite materials (graphite fibres and the like). steel is the only magnetic metal employed and its use is mainly limited to engines.

 

most of the more feasible clean up methods that have been proposed employ some means of slowing down the object that we want to clean up, meaning that it re-enters in a more or less controlled way. the downside is that this works better for the larger pieces. the countless smaller pieces are very hard to clean up and probably present the biggest risk.

[belovelife]

i'm actually talking about a a magnet driven orbiter

 

with a network of large magnets, you can push, or pull an orbiter,

 

change its vector, and all of that

 

so, use the magnets as a propultion system, without propultion of course

 

so there is no need to refill on gas

[blamski]

ah yes... so you are. sorry about that. :rolleyes:

 

so i wonder how you could affect the vectors of the desired orbiter, without affecting the orbits of all the other things you don't want to affect. could be chaos up there...

[belovelife]

i was pondering that also

 

i think it would all have to do with timing

 

and the orbits of the objects would change as you repel or attract the orbiter also

then again,

 

you could use the iss as a tare point

 

reset orbits as the station passes by or something

 

i don't know if our magnets are powerful enough to do such a thing though

[belovelife]

ok, so how about a teathered system where it connects to the iss

 

and has a teather kilometers long

 

then you have something similat to an inflatable module

that is the electromagnet

 

so as the iss orbits

 

you can release the teather in a controlled fashon to intersect the orbit of the

 

cleanup module

 

then yolu retract the teather until neccisary to intersect the orbit again

 

with multiple large electromagnets, you could control even if in small increments

 

the orbit of the cleanup module

[CraigD]

To see the problem with using a magnet to clean up orbiting space junk, you’ve got to look at how a magnet works.

 

The precise math of them is complicated, but a sketchy image isn’t, and can help you understand the math.

 

A magnet (permanent or elecro) generates a magnetic field. Feromagnetic materials, such as the steel (but not aluminum) in a piece of space debris close enough to this field will align the atoms in it to essentially become an extension of the magnet.

 

The problem here is, that unlike electrostatic attraction, which follows a simple distance squared law (

[math]|\boldsymbol{F}|=k_e \frac{|q_1q_2|}{r^2}[/math]

), magnetic field strength follows, approximately and complicatedly, a distance to the fourth law (

[math]F_r(\mathbf{r}, \alpha, \beta) = - \frac{3 \mu_0}{4 \pi}\frac{m_2 m_1}{r^4}\left[2\cos(\phi - \alpha)\cos(\phi - \beta)- \sin(\phi - \alpha)\sin(\phi - \beta)\right][/math]

)

Ignoring all but the essentials of this, we can see that a magnet that attracts a magnetic material with a force of, say, 1 N at 1 m will attract it with only [imath]\frac{1}{16} \,\mbox{N}[/imath] at 2 m, [imath]\frac{1}{10000} \,\mbox{N}[/imath] at 10 m, etc.

 

A powerful electromagnet like the kind that lifts scrap around a scrapyard has a force on a big piece of steel of perhaps 100000 N, at a distance of perhaps 0.05 m, so at 1 m, the force would be down to about .625 N, about the weight of a golf ball. At 10 M, it’s about 0.0000625 N, about the weight of a fat housefly, at 500 M, about .00000000001 N, like a grain of sand. If you’re trying to attract a piece of space debris at a distance of few to a few thousand km, the force is a miniscule fraction of the force of random dust or solar wind particles.

 

If you want to push stuff around in space without physically touching it, you need something that follows a nice distance squared force law, such as a “laser broom”

[belovelife]

heard of the laser broom, and other, lens focused light in space to cause the surface to evaporate or otherwise cause the matter to move,

 

but this gathering of material could be useful

 

recycle in space