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JAXA To Use Fishing Nets To Scoop Up Space Junk
An anonymous reader writes "We've seen high-fallutin proposals to tackling the space junk problem before — and now the Japanese space agency JAXA has teamed up with Japanese fishing net maker Nitto Seimo to haul in some of the 100,000-plus objects of space junk orbiting the planet. AJAXA satellite will deploy and release a kilometers-wide net made by Nitto Seimo of ultra-thin triple layered metal threads. The net will gradually be drawn into Earth's magnetic field and burned up along with the abandoned satellites, engine parts and other litter it's collected."
What are they doing to make sure the net doesn't also entrap space dolphins?
I've abandoned my search for truth; now I'm just looking for some useful delusions.
One potential snag in their line (see what I did there?) could be the fact that some of these objects are moving in different or opposing directions. A single BB at 20000 km/h can burn through a solar panel array, what's to stop it from passing through a fine net? It'll still clean up lots of junk even with a greater-than-anticipated amount of holes, but there will certainly be discrepancies between projected results and actual.
What else can happen when an unstoppable force collides with an immovable object?
"ABC News reports that since JAXA launched it's 'Space Net', mysteriously all communication and research satellites have been taken offline, except the ones belonging to Japan. As a result, stock prices for communications companies world-wide have plummeted except, of course, in Japan and have created panic and chaos on a global scale. Companies are now struggling to build and deploy hundreds of new satellites, but in the meantime are forced to piggy-pack services across Japan-based companies. For now, ABC news must be referred to as JBC. Back to you, Chou Youn..."
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If you look at the details, there is no net involved. A company which makes nets is also able to make webbed rope-like material, and this is being considered for installation on a satellite before launch. When the satellite is no longer useful, the electrically-conductive tether would be extended, and induced electromagnetic forces would drag the satellite out of orbit.
What the heck are you reading? From TFA (and TFS accurately):
A JAXA satellite will deploy and release a kilometers-wide net made by Nitto Seimo of ultra-thin triple layered metal threads.
And that's about as far as it goes. TFA says nothing about tethers.
Yep, especially #2. Orbital dynamics means your not going just sweep stuff up in the same orbit you are in.
A fun way to see this all demonstrated is a little iPhone game called "Osmos", you're a mote have to go along and try to absorb smaller motes. Many of the scenarios involve a "sun" that everything is orbiting around. It quickly forced me to remember my school day courses on orbital dynamics and how to do a Hohmann transfer, etc. It's decent entertainment (and no I'm not the developer)
But as you'd see in the game, you need to be in a more eccentric orbit and sweep through other orbits if you want to pick other stuff up. And the delta V's involve lead direct to the parent's points #3 and #5... they will go right through the net.
Of course Japan would be the ones to bother with this. Thank you, Planetes
There's also the fact that nets don't work on a velocity basis. They work by acceleration. That is, the net moves at one velocity, the water moves at another, and the fish, when it contacts the net, is now stuck between two forces acting on it in opposite directions. It's being accelerated by water drag, and held in place by the net.
This space-net would have to be "sticky" in order to keep anything it captures in contact with it. So either it folds up around it, which means game-over for catching anything else, or it has some exotic means of latching onto randomly-sized and -shaped things.
Plus, again, if it has no propulsion system, then after it hits the first object it will have an unknown orbit. Inelastic collision of a rigid object and a floppy object will give you a wide range of resultant velocities.
The more I look at this idea, the more I think it's the result of the Japanese version of April Fool's Day. Unlike that day when they all go out and worship the giant penis effigies. That's totally legit.
Instead of throwing all that potentially valuable material into the pacific ocean, why not coral it all into one big "trash heap" and recycle it? After, it takes a lot more energy to put something into orbit than it does to move something to another orbit. At the very least, the trash heap could serve as a testing ground for space manufacturing processes.
I'll catch this bird for you, but it ain't gonna be easy. Not some LEO screw or spaceman's glove. Bad sat, 1960s. Three tons of 'im. Geosynchronous 'fore it went driftin'. RTG battery backup. This sat, swallow you whole. Little shakin', little tenderizin', an' down you go. And we gotta do it quick, that'll bring back your uplinks, put all your businesses on a payin' basis. But it's not gonna be pleasant. I value my neck a lot more than $300 million, chief. I'll find him for three, but I'll catch him, and graveyard him, for ten. But you've gotta make up your minds. If you want to stay alive, then ante up. If you want to play it cheap, rely on fiber-op. I don't want no salarymen, I don't want no mission specialists, there's just too many captains on this island. One billion dollars for me by myself. For that you get the bus, the payload, the solar panels, the whole damn thing.
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Prisencolinensinainciusol. Ol Rait!
The show was set on the United Galaxies Sanitation Patrol Cruiser, an interstellar garbage scow operating out of United Galaxies Space Station Perma One in the year 2222. Adam Quark, the main character, works to clean up trash in space by collecting "space baggies" - unfortunately for Quark, while circumstances frequently dropped adventure into his lap, he was always ordered back to collecting garbage when the action was over.
http://en.wikipedia.org/wiki/Quark_(TV_series)
Kinda like the gelatinous cubes in AD&D would clean up the dungeons. Figure out a way to manufacture aerogel cubes in space. NASA used aerogels to capture cometary particles because the high impact velocity with a solid would obliterate or vaporize the particles. It could turn a small piece of debris into a thousand smaller pieces of debris. An aerogel would decelerate the particle slowly enough that it could be captured intact. You want something like a cube because you want a big cross-sectional area to increase the chance of a collision - a sphere is the least effective design. Just put a bunch of them in known orbits. The smaller debris like paint chips which hits them will be captured within the gel. The bigger debris we already track and can be avoided. After a few decades, either de-orbit them, or just leave them up there since each should be big enough for us to track.
Really, so they do collect the fish one at a time?
Yes, but only if they're using one of the bespoke fishing nets. They're totally exclusive and only available to high-rolling fish hunters (we don't call them fishermen anymore). They can even match the color of the fishing net to the color of your car or your tie. I should know -- I have two of them, myself.
It's the hot new sport of the rich for 2011. 'Bespoke Fishing: When you have nothing better to do with your money."
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