Slashdot Mirror
More on Orbital Space Debris
wvanhuffel writes "This is a call for /.'s to put their thinking caps on. The US Airforce, NASA and other agencies are looking for ideas to find and eliminate threats from space debris to craft (space, in the use of).
Personally I like the idea of "robots to serve as roving garbage scowls" - my question is "How do they identify 'garbage'?" - Would the ISS qualify?" I don't know what happened to the laser broom.
Obviously this only works for grit and other small things.
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
"No, bad robot, the earth is not debris."
Yes it's time for slashdotters to put their thinking caps on. I'm sure our geek aura will penetrate a problem that has had the best minds of the world's space agencies stumped for decades.
I await with glee the hoards of posts suggesting enormous ballistic inflatable penguins and fleets of linux powered robotic red swingline staplers. But what about prevention in the future? Easy, just make all space objects run Windows, that way they will crash themselves into the blue ocean of death eventually.
There, I've got it out of the way early so hopefully others won't need to.
Karma police, I've given all I can, it's not enough, I've given all I can, but we're still on the payroll.
Nowhere in the article do they discuss plans/methods to avoid making the problem worse. Shouldn't there be an international standard, at least among the ISS participants, for getting new space junk out of the way? A French satellite collided with remains of a French Arianne booster. Wouldn't it make sense now to define a standard procedure for ensuring that junk is sent on a destructive re-entry? If they use a verifiable method of ensuring destruction, it could help in assigning responsibility. And insurance companies could use that in assigning premiums (or littering fines ;>) on satellites, etc.
When I was a young 'un, my mother used to cure the embarrassing problem of wool-bobbles on clothes by wrapping a hand in inverted adhesive tape (sticky side out) and running it bruskly over the surface of the affected garment. These days, the rise of the mighty Remmington Fuzzaway (tm) has largely rendered this practise useless.
I believe however, in consultation with my mother, that this might still be applied to the above problem. I propose a giant space hand, sheathed in cellotape and waved liberally about in orbit would be the best method.
http://www.davetansley.com - you proba
IIRC there are about 200 000 objects ranging from milimeter size pieces to fat chunks of metal in orbit around our planet. Someday one is going to take out a spacecraft or satellite or damage one seriously. Obviously, it is going to be a lot of work to get rid of these pieces of scrap. So my carefully thought out proposition ;)...
1.Catalogue them -- A database with all known objects and their orbits is the obvious first step
2.Build a sateliite with a relatively low power laser, charged by solar panels. An alternative would be a simple kind of large, thick metal "shield" that would simply get in the way of the space debris.
3.Place a ion engine on the craft.
4.Write software that would automatically select the nearest target from the db and move the satelite into position to evaporate or impact with the debris.
5.Very importantly, have an operator or command center that would be required by the software to OK each impact so that the satelite doesn't get misused or highjacked.
6.If using the satelite with a big metal "target shield", eventually the shield will become useless. It can be pushed into reentry by the ion engine and can then burn up on reentry, the ion engine then climbs back into normal orbit and is fitted out with a new shield by a drone rocket.
7.It will take many years but will start to show progress over time. Good that it will give the operators in the command center work and enable them to read books, playgames etc inbetween hits.
First off, any kind of collector device deployed in space is totally impractical. For one thing, the mass of the device could easily end up being equivalent or even greater than any debris collected. That is, you'd need as much or more propellant and material to grab the micrometeorites and garbage in the collection robot as the mass of the stuff being collected. This means you'd have to spend as much money on boosters as we spent putting junk in orbit over the past 40 years. That's a lot of money...
Why launch anything into orbit at all? A far better solution would be to build a powerful enough ground based laser system to convert the garbage into vapor. It would be cheaper, as you would not have to spend vast sums of money trying to minimize failures (if the laser on the ground breaks, you get out tools and fix it. If the orbital robot breaks you just blew a lot of money). To detect the rapidly moving orbital debris you would need an extremely high resolution radar...at least one of the X band things being build in Alaska.
The laser would be an array of linear accelerators in parallel (or cyclotrons) that would accelerate electrons that would release the energy in the beam. (A free electron laser) Such lasers are inherently very efficient, and the system would only use electric power that could be obtained off an ordinary power grid (a LOT of electric power...you'd need some sort of temporary storage perhaps giant rotating drums or something)
And the best part? A multi-megawatt laser array, capable of hitting extremely small fast moving targets with enough power to vaporize them...
Certainly the Pentagon could think of a use for one of those.
Say, missile defense?
Such a system would be FAR more reliable than a rocket booster interceptor that has THOUSANDS of possible points of failure. If the wrong part fails, the booster fails. With a parallel array of lasers if one fails its no big deal. In addition, given enough power it would be able to vaporize all the incoming targets, decoys and bits of insulation and all.
"Spaceball 1 has now become ... Mega Maid!"
I think NASA should hire Roger Wilco to clean up the mess. He has excellent CV for this kind of stuff..
yush
Been watching too much SG-1 lately? You know what happened to them, don't you? If NASA takes your idea, the Asgard are gonna be pissed.
A far better solution would be to build a powerful enough ground based laser system to convert the garbage into vapor.
How can you possibly believe that?
First, a laser on the ground would have to have a crapload of power since the vast majority of it would be dissipated by the atmosphere.
Next you have to refine the optics to an extremely high degree so that the beam is still focused at the target. Even the slightest bit of divergence really adds up over hundreds of kilometers. To vaporize high tensile strength steel requires a lot of energy, and most of these objects are very small -- both are reasons for needing a focused beam.
Also consider that they are traveling at tens of thousands of MPH. It would be almost impossible to servo track the object, so your laser would have to work with a single high-energy pulse. You'll need a very high peak pulse power to deliver enough energy to do any serious damage. And this ignores the fact that we can't actually track the majority of the debris. The ground based laser thing would need extremely precise tracking information which is just not available for anything but the large stuff -- which we can already do a fine job of working around. Also consider the aiming accuracy necessary to precisely hit a small target a few centimeters or smaller from hundreds or thousands of kilometers away. Then there's the issue of all the crap in the way between your laser and the target which could cause diffraction, scattering, dissipation, etc.
In the 80s the Star Wars thing was going to cost how many billions (75?) to disable (not totally vaporize as you propose) much larger objects traveling at more certain orbits, and was called a technical impossibility by many engineers who read the proposal. And even this plan would have used space-based lasers so the distances and dissipation factors was not as bad.
What you are proposing would never work. Get real.
NASA is already using AeroGel in the StarDust mission to collect high-velocity particles.
Thick enough, it could be used to capture those tiny bolts and fragments they can't track by radar.
Also, one of their concerns about using lasers to zap bigger debris was the fear of generation bazillion smaller particles that couldn't be collected or tracked thereafter.
Why not create an autonomous robot that circles the globe, zap the objects it can while collecting the smaller debris in an AeroGel fish net?
Think it won't hold up to the task? Check out the photos of AeroGel. The fluffy thing can hold up a brick!
When you think that NASA spent countless $$$ to come up with a pen that would work in space (in a zero grav environment) to come up with a very expensive system (involving ink being put under pression) where each pen would cost over $10,000.
When the obvious solution (used by the Russians) was to use a pencil...
I think that having this kind of question opened to anybody can only help...
Black holes occur when God divides by zero.
You can always trust Rober Forward to come up with a good idea.
See his Terminator Tether page. It's a great way to bring down an orbiting mass without actually having to carry the mass of fuel that would be required for a deorbiting burn.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
The Spring 2002 issue of Artemis Magazine had an excellent article on this by Henry P. Cate, Jr., titled the "Junk Man's Ladder". The idea is to put up a tether (many kilometers long "rope") in a convenient orbit with electrodynamic lift capabilities and some thrust, move it around to "catch" space debris, and move the junk up to the center of mass of the tether, to give it greater stability. Tethers like this are form of "space elevator", able to lift move things from low to high orbit with high efficiency. More on orbital tethers can be found at Tethers Unlimited Inc., run by Robert L. Forward and Robert P. Hoyt (who I was fortunate to have dinner with a couple of months ago).
Energy: time to change the picture.
Get some sort of mesh "net" made out of whatever metal is deemed strong enough and have these nets surround whatever it is you don't want to get damaged. I know it sounds really low tech and bulky, but hell it's cheap and would probably work.
~ now you know
First and foremost, any solution needs to consider the economic factor. A solution that pays for itself will be a hands down winner.
Second, it seems like many of the solutions here would create more debris than already exists. A single large satellite is far simpler to track and avoid than a few thousand pieces of that large satellite. Unless your lasers or other weapons completely convert the debris into energy, you're wasting your time. Even if they force the debris toward Earth, the question would remain of "how did they do it"? The answer is by vaporizing matter which blasted away in the opposite direction. That matter is now not only debris in space, but untrackable debris. Even a paint fleck can do (and has done) serious damage to another orbiting object.
Third, THIS SPACE JUNK HAS VALUE!!! If its matter, and its in orbit, it is worth thousands of dollars a pound. It blows my mind everytime they guide something down that took millions too get up there instead of coming up with a way to get stuff into a parking orbit. Eventually, probably even today, there should be enough materials in space to justify manufacturing in space instead of sending more stuff up.
Steps we should take to turn this lead into gold include a) all future items launched should have provisions to reach an orbiting factory/storage facility at the end of their expected life. b) they need to all have provisions for capture via forces instead of mechanical means. This might mean adding magnetic materials or something. This way, an orbiting vehicle could capture them without contact that could cause further scattering of debris. c) software needs to be developed that can calculate capture plans for multiple objects that utilize the energy (stored in the momentum) of the objects captured effectively to help reach the next object and eventually get back to the orbiting factory/storage facility. Sort of like a game of 3D billiards. d) automated recycling and manufacturing technologies need to be developed to turn these raw materials into useful things like airtight habitat shells. At least initially, we'd probably have to keep bringing the high tech chips and stuff up the hard way, but the heavy shells and stuff could likely be very effectively manufactured in space. Things like girders for the space station should be relatively easy to do.
BBCnews reported some time ago on such a posible role for Surrey Satellite Technology's nanosatellite SNAP program. A swarm of cheap (at about 100,000 UK sterling) manuverable tiny satellites that can latch onto and gradually deorbit junk.
How though could such carry enough reaction mass to actually slow something down enough? Info on its propulsion system is here (pdf). Could you just do it via its flywheel? Or use such to cluster together junk for collection by something bigger?I could certainly see a role as a beacon to actively tag stuff (on the net even!)rather than relying upon constant ground based monitoring.
troodon.net
- into decaying orbits or
- a designated "trash ring" or
- push it to escape velocity
depending on specifics of each piece of junkFunny as it sounds, this could work. A proactive strategy would be based on using single hits over multiple targeting windows to push each piece of junk into decaying orbits or to shepherd junk into a trash ring where our grandkids could mine it (what will be the multiplier for the value of a chunk of scrap metal that is already at orbital velocity?). Beebees that miss would add an insignificant amount of water vapor to the upper atmosphere or leave near Earth space. Each shot would cost no more than the cost of the beebee-- the power is free. Someone could figure out the ratio of the size of the solar array to the number of shots that can be fired in month's time. My wag is that with collectors comparable with today's, the thing could manage a few shots a week.
A program like this would need a good name. I suggest "Space Balls"
The article is a bit heavy on the space-junk media hype. The practical answer is to let nature take its course and work toward prevention.
Any method of attempting to destroy debris isn't going to be practical. Giant debris collectors deliberately placed in dangerous orbits are likely to simply be smashed to pieces rather than gather any meaningful quantity of debris. Laser systems could vaporize metal fragments, but this vapor will simply congeal into globlets and cool into the space equivalent of bird shot. Until we develop gravity disruption fields, there is no effective way to affect the orbits of debris. The best bet is to wait the problem out. LEO is unstable. The Earth's atmosphere bulges significantly during solar maximums, and this drag has the effect of cleaning out the spacelanes within a reasonable period of time. In time, the problem (at least at LEO) will take care of itself if we can stop adding to it.
I'm pretty sure the following is being done, but there should be restrictions on any mass accelerated to orbital speeds. Specifically:
Or, we could just use the Q solution. Simply change the gravitational constant of the universe.
Some sort of silicon foam that is pressurized in a gigantic can and when sprayed forms a cloud that hardens into some bubbly sticky material. Debris can hit this from any side and either stick to it or penetrate it and decellerate while inside and maybe not even exit it on the other side.
You can't handle the truth.