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Using Lasers and Water Guns To Clean Space Debris
WSJdpatton writes "The collision between two satellites last month has renewed interest in some ideas for cleaning up the cloud of debris circling the earth. Some of the plans being considered: Using aging rockets loaded with water to dislodge the debris from orbit so it will burn up in the atmosphere; junk-zapping lasers; and garbage-collecting rockets."
Wouldn't it be extremely expensive to send large quantities of water into orbit (also, our water supply is limited we can't be throwing it into space!)?
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Of course, you'll need real hardware to go with that.
> Sharks can fly to space?
That's what the water is for.
Not only would lofting water into space be a colossal waste of energy and water, it would only exacerbate the problem!
IMHO the only 'clean' way to deorbit debris is to add energy to the debris in the retrograde direction without using additional mass, which means photons. Laser pulses could do it either by radiation pressure directly (huge laser), or by pulses that ablate the debris slightly (creates tiny beads of additional debris).
Electron/proton beams would work as well, as would alpha particles, but they'd pose a risk to humans in space. In fact, using charged particles might induce a charge on the debris that would then help direct the debris toward it's doom (debris vector, Earth's magnetic field, right hand rule....whatever).
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
What do you think would happen if you push an old satellite with some type of nuclear fuel into the atmosphere and it doesn't burn up completely the way you want it to and it basically becomes a dirty bomb in high orbit.
ZOMG!!!! You're giving terrorists ideas!! I'm reporting you!!!
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
http://en.wikipedia.org/wiki/Planetes
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One cubic foot of water is around 60 lbs.
I thought that number sounded a bit high as a gallon only weighs about 7 pounds, but sure enough, a cubic foot of water DOES weigh around 60 lbs. 62.42796 pounds to be exact. And a gallon is actually just over 8 pounds.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Orbital mechanics work in strange ways. For example, in a circular orbit, you don't thrust up to go up, you thrust forward. Going down, you thrust backward.
In this case, your best bet will be to hit the forward side of the object. If that's not possible, then hitting the bottom of it (depending on where it is in the orbit) will also have an effect. I can't remember offhand what happens from in-plane radial delta-V application, but I think it's a combination of changing the eccentricity of the orbit without affecting the total energy, and changing the longitude of periapsis. Sorry, it's been a couple years since I took orbital mechanics...
Now if you get a space-based laser up, you get more freedom in how your burns are applied.
The meek may inherit the earth, but the strong shall take the stars.
Since space is a "near" vacuum wouldn't the water flash to steam instantly and be useless?
The enthalpy of vaporization for water is very large. On exposure to vacuum, immediately the water will begin to boil. This will very rapidly cool the water so that most of it ends up freezing (the enthalpy of fusion is comparatively much lower). Not only does this make mathematical sense, but it's witnessed daily on vacuum lines in labs.
"I zero-index my hamsters" - Willtor (147206)
Doesn't work. The impactors will just break loose pieces of the ice. There has been some thought put into using Aerogel, since it has density low enough to not explode when hit by something going very. fucking. fast.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Which puts us one step closer to landsharks.
*knockknock* "Plumber!"
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Yeah, someone from Caltech said the same thing, but you can't trust second-rate sources when it comes to space analysts...
Now that I think about it, I'm pretty sure everything I just said is completely wrong.
Given the price of launching things to space, you could use scotch whiskey instead and it wouldn't affect the cost or feasibility of this plan.
Unfortunately, most of the folks on here are probably too young to get the reference, so, here's some text from the original boxes:
Build it, and they will come^Hplain.
Something doesn't seem to add up. They've already indicated that slight modifications to trajectories can deteriorate an orbit, so some portion of the space junk caused by collisions must fail to remain in orbit. But they also say that collisions cause more junk, which causes more collisions, as though this were a never-ending cycle of feedback.
It seems as though there must be a threshold somewhere where the introduction of further space junk removes from orbit, on average, an equal amount of debris as it introduces. The farther past this threshold, the more likely that introducing debris will remove more than is introduced. There must be a point of equilibrium.
Take the following exaggerated scenario, for example. Let's say that by chance or plan, there is debris in orbit within every cubic meter at stable altitudes. (I am not a physicist, but this seems highly improbable statistically.) The introduction of a meteoroid through this debris field would almost certainly cause a significant chain-reaction with many affected objects acquiring unstable orbits leading to failure.
Not-to-scale pictures aside, I doubt we're anywhere near such a threshold -- even if we are reaching a point where our ability to avoid debris is insufficient to mitigate the danger. But surely it would be at least interesting, if not practically useful, to know this "saturation" point.
Or perhaps this is already known, and I am just unaware.
We spent hundreds of hours in front of the Astroids simulator, practicing breaking rocks up into smaller rocks!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Saturns rings would like a word with you. ;)
j'ai découvert une démonstration vraiment admirable (de ce théorème général) que cette si