Obvious really...
They need a vacuum cleaner.....
The noted US military bonkers-boffinry bureau, DARPA, announced yesterday that it would like to hear from anyone with ideas for cleaning up the large amounts of space debris orbiting the Earth. Aerospace globocorp Boeing has already indicated that it is interested. According to DARPA: Since the advent of the space age over …
Lewis,
Space work is an odd field and if that is mad DARPA [and I do love your restrained and understated "is institutionally a bit, you know... special"] phishing for a Special Alien Solution to render the Environment Virgin for a Novel Bite at IntelAIgent Cherries, then they will have to Act Bravely and make a Bold Offer rather than Playing Foolishly/Coyly with words ..... "That said, however, the ODR effort is only a request for information for now. No funds have been set aside, and DARPA says it "does not intend to award a contract on the basis of this... or to otherwise pay for the information solicited".
A mid size/large electro magnet, setup in a partially degrading orbit.
First, you put it at the highest orbit you can, allow it to circle, slowely leaving orbit heading to earth.
Along its trip, it collect any metallic objects in orbit.
Then, you either have rockets attached to send it back into a higher orbit for later pickup, or allow it to enter atmosphere to burn up.
It costs thousands of dollars per Kg to put stuff into orbit; if and when orbital manufacturing facilities become a reality, this junk could be a valuable resource. Why not just coral it together into a sort of space scrapheap ready for resale?
You could use small robot ships to herd the stuff intp a safe place, maybe even tether it all together, and I'm sure this would be cheaper than just de-orbiting all the non-functioning crap currently in orbit.
Had a thought about this (ahem) several years ago...
Internal iron core electromagnet (14kg) with a field strength capable of attracting ferric materials to it or attracting the satellite to the material. Surrounding this core would be approximately 9m to 12m of expanded gel material in flexible polymer sphere. A boom (think long PVC pipe) would house retractable solar panels for recharging the battery for the magnet, as well as motor module for acceleration/re-entry, through a conduit in the bag.
When deployed (preferably in waves of single satellites against fields of debris), the gel is activated by bi-chemical release into the sphere. The chemicals expand, mix, and form the gel.
The gel is spongy enough to absorb the impact of materials as they encounter the node. Either the gel will completely encapsulate the material, or slow it down to the point of rapid degradation of its orbit (think ballistics jelly and bullets). The ferric core will also help bring it to a slower speed (and quicker re-entry). Larger objects encountered that make it through the gel and contact the core would merely increase the mass of the electromagnet, increasing its field strength. The key is the simplicity of the onboard systems; it is expected that the ferric core will take great shocks from impacts that reach it; it is just a mass of iron core with wires wrapped around it. All electronics are internal to the core, and shielded; as they are in a relatively stable field (ie. not moving through magnetic flux lines), the logic should not be affected.
This device would be relatively inexpensive (compared to most any other artificial satellite), easily mass produced, able to collect the very large percentage of material that is *not* magnetic, and light to launch (compared to the several ton comms gear). The design is also completely scalable to larger versions for either large debris fields or larger targets.
Estimated life span would be 3 months, at which time it would be expected that enough debris was collected by that one, and allow it to burn up or collect for processing at a rendevous orbit... getting a few of these together in one space with the magnets on, and you have a self collecting depot. :)
Just think of the "junk" from other countries picked up and collected for the next manned collection mission... How much should I charge the NSA for that? :)
We've all heard the saying that the best defense is a good offense, and that's certainly true in this case. The best method for eliminate orbital debris is to not create it in the first place. In other words, pick up after yourselves. Don't toss the fridge out the nearest airlock.
@Mike Richards
"5km of Vapona fly paper in low orbit... Simple - that'll be $1 billion please."
If only that would work... You know they'll spend more than $1 billion simply discussing possibilities and giving pork to the aerospace industry. Then they'll spend $100 billion on a trial run before giving up and admitting that it's a hopeless cause. Then they'll continue to eject junk into space, generating more orbital debris.
Naaa. Group it in high orbit and then use orbital mylar solar mirrors to smelt it. The resulting ball of stuff could be used for orbital construction, or de-orbited in some relatively insignificant place in the middle east ;-)
I'm sure us 'murricans can come up with a candidate.or two
... until the Chinese say that the bit of space debris they just collected belongs to them and that touching it was an act of war against them.
... or until they have to catalogue *everything* and its origin to determine what *not* to touch.
... or until they dislodge something from orbit and it ends up flying through the ISS and killing everyone.
... or until the collector is utterly destroyed by the sheer speed of some of that stuff, or other space debris.
It's a ridiculously humongous task that's not going to be solved by some casually interest, or interstellar flypaper.
Velocity matters; the stuff is moving very fast in all different directions. Anything standing in its way is likely have a hole poked in it or worse, blown into many more pieces compounding the problem. I don't blame DARPA for being weaselly since the problem is so intractable. One the other hand, we could promise Congress Critters that they could use their campaign coffers to collect the stuff; then even the planets wouldn't be safe.
What's needed is a sticky sponge net blanket. Something that will catch the debris at decent relative velocities, and you can guide it around from patch to patch.
Yeah, I saw Planetes. Nobody is going to fund people to scoop every little screw. All of it will be done by robots and ground-based remote control.
Get all the crap the rest of you left there, give me a call asap
Alternatively, should we stop sending stupid transmissions into space and possible aim
a few "Please come help with the clean up party" messages at amanfrommars?
I'm sure he, could setup a SpaCeJuNK ReMoVaL SErvicE
Did you see what I did there, WOW I am so proud ^H^H^H^H^H Smart
Go for it, pay me in beer
While "I didn't do IT" did say "capable of attracting ferric materials to it or attracting the satellite to the material", I note that in various places where orbital debris is discussed, a lot of people don't take in to account the fact that attracting something with a magnet is going to make you move towards it as well as pulling it towards you, so you're either going to have to use a *LOT* of fuel in thrusters to keep yourself in your current orbit, or have your orbit degrade at an unknown and variable rate (making it incredibly difficult to work out when you need to do burns etc to deorbit in the right location, and even to avoid colliding with something and adding to the debris problem!).
That's quite apart from the fact that it assumes all the debris is ferrous and will actually be attracted by your electromagnet - satellites generally have a lot of aluminium in them because it's nice and light etc...
They are too small to be decellerated by travel in the very thin upper atmosphere. Once they slow below orbital velocity they can re-enter and burn up. The problem is how to increase their drag or slow the objects.
One option would be to charge the objects (EG by UV laser). The charged object cutting the Earths magnetic field would excert foce and begin to decellerate below orbital velocity. The fact they have remained in obit suggests they are too small to be slowed by natural forces in any reasonable timescale.
With this many objects to deal with (and those are the ones that are detected) something which can cover large areas of sky is going to be needed. Of course it might still end up being pants. But something will have to be done and let's see more of that high risk, high return daffiness.
Toss a few nukes in orbit once over the pacific ocean blow them up 1 by 1 in a timed one day manner
Any passing orbiting junk will be blown out of orbit by the shock wave of each nuke
since the middle of the pacific ocean is just water you can quite happy detonate a few nukes over it in space
The bits of junk are moving so fast that any kind of physical entrapment would be very difficult. How about getting rid of the junk without having to actually catch it? An array of orbiting mirrors could focus sunlight onto an object and heat it until it vapourises (stuff can't cool down easily in a vacuum so it will get very hot fairly quickly). The mirrors are re-useable forever(ish) and don't require any energy input other than for aiming.
The tricky part is finding a way to catch or change the direction of something the size of a bolt, zipping by at one earth circumference every 2 hours, while searching an area of 11 kilo-wales (54 kilo-Rhode Islands) while orbiting on a platform also zipping at one earth circumference per 2 hours (so you can't just wait 2 hours for the object to reappear).
Since anything capable of whacking a bolt out of orbit into the atmosphere could also hunt satellites, there might need to be a new amendment to the Outer Space treaty to circumvent the prohibition on space weapons.
Regarding the mechanism that is fast enough: I recommend relativistic particle beams, or 'nuke nobbling laser' technology.
Will you STOP stealing our patents, We're sick and fed up with your unfairness
WE created this patent to collect up the wealth of precious metals just abandoned in earths orbit
You can't come along and just steal our patent.
Now get back down that hole you dug for yourself
Yours
Microsoft Space Debris Devision V7.0
I guess a lot of the stuff is aluminium. Plus, one of the most crazy 'experiments' was the "Westford Needles" (link follows) - 480 MILLION copper needles as 8GHz reflectors.
Supposed to come down in 3 years, there are thousands of them up there, almost ½ a century later. OK, tiny, but fast moving. Could have someone's eye out up there! Oh, and think of the children, and the muppets who came up with this idea, natch.
http://en.wikipedia.org/wiki/Project_West_Ford. See reference [11]
Now, where are the bin inspectors? Wonder what the fine would be? Astronomical! (sorry)
AC@08:56
"Toss a few nukes in orbit once over the pacific ocean blow them up 1 by 1 in a timed one day manner"
Been tried in the early 60's. Google for "Starfish" test. The 2 problems are it the massive EMP generated, which proved very effective at trashing power grids and that while there are air molecules to transmit a pressure wave (the "top" of the atmosphere can vary by at least a factor of 2 during a day) it's a *very* low air pressure.
@Martin Budden
"An array of orbiting mirrors could focus sunlight onto an object and heat it until it vapourises"
I think this is the sort of proposal DARPA is looking for. A cloud of metalic vapour would be fairly harmless. However they would probably want confirmation that it would not gunge up the lenses off any low orbit imaging sensors the Pentagon might deploy.