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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"
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.
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.
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.
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.
- 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"