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Japan Sends Its New Space Junk-Fighting Technology To The ISS ( 64

What floats 249 miles in the sky, stretches 2,300 feet, and took over 10 years to develop? An anonymous reader quotes Japan launched a cargo ship Friday bound for the International Space Station, carrying a "space junk" collector that was made with the help of a fishnet company... Researchers are using a so-called electrodynamic tether made from thin wires of stainless steel and aluminum... The electricity generated by the tether as it swings through the Earth's magnetic field is expected to have a slowing effect on the space junk, which should, scientists say, pull it into a lower and lower orbit. Eventually the detritus will enter the Earth's atmosphere, burning up harmlessly long before it has a chance to crash to the planet's surface.
Bloomberg has some interesting background: The experiment is part of an international cleanup effort planning to safeguard astronauts and about $900 billion worth of space stations, satellites and other infrastructure... Satellite collisions and testing of anti-satellite weapons have added thousands of debris fragments in the atmosphere since 2007, according to NASA... With debris traveling at up to 17,500 miles an hour, the impact of even a marble-size projectile can cause catastrophic damage.
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Japan Sends Its New Space Junk-Fighting Technology To The ISS

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  • finally, someone is testing solutions for this problem.
    • If you are imparting kinetic energy on space junk, then it is imparting kinetic energy on the station. I expect keeping the station in position just got more expensive.
      • Re:about time (Score:4, Interesting)

        by rickyslashdot ( 2870609 ) on Sunday December 11, 2016 @10:06PM (#53466233)

        Get a grip and RTFA and links - - - as "the satellite was removed from the rocket" and put into the planned orbit about 15 minutes after the liftoff - Read more at: []

        It's NOT attached to the ISS, it's detached and 'doing it's own thing'.

        Besides, there is an on-going research project to equip the ISS with proven ion propulsion units to provide 'station keeping' capability with the extremely efficient ion engine technology - - - just a matter of time before the requirement of using the supply launch vehicles' secondary engines to boost the ISS into a clean orbit will be a 'thing of the past'.
        Granted, the high-impulse delta-V of the secondary engines will still be needed for 'emergency' maneuvers to avoid the occasional wandering debris near-encounters, but the day-to-day orbital maintenance of the station can be relegated to very low cost ion engine technology.

        cheers . . .

      • Re:about time (Score:5, Informative)

        by wagnerrp ( 1305589 ) on Sunday December 11, 2016 @10:10PM (#53466251)
        The Space Station isn't going to be doing anything to space junk, except trying to avoid it. The supply craft is carrying this tether device to test its performance. After it drops off its payload at the Space Station and detaches, before it is de-orbited, it will unspool this tether and see if the electrodynamic drag produced matches predictions.
      • Of course this won't work on anything in a geostationary orbit where it doesn't experience any change in magnetic field.
      • You need to get this information to NASA IMMEDIATELY!
        I suspect they never considered it.
    • This actually seems to be an economically feasible solution to de-orbiting space junk - a light-weight 'fishnet' using the earth's geomagnetic field to degrade the velocity of captured debris - no rockets, no fuel, no guidance - simply a light-weight tethering system that 'captures' or ensnares the debris and slows it enough to degrade quickly (relative speaking - days/weeks vs years/decades) and drops the junk into an atmospheric burnup.

      GO JAXA - - - wish NASA had the funding and initiative to do the same

      • Since the oceans are now fully choked with discarded fishnets guess it follows we would pollute the cosmos with the same.
        • lol - good one.
          A few points of interest -
          these 'fish' nets are metal (not nylon/rayon) and would degrade quickly in the oceans waters even IF they reached the surface
          these 'fish' nets would, in all probability, disintegrate upon re-entry burnup, and not even reach the surface
          even without the above, these 'fish' nets would be REALLY few and far between, not like ocean fishing trawlers
          and, being metal, even without the salt ocean degradation, they would SINK, not float like plastics

          And, if you want to discuss

          • I think people would be more concerned about these space fish nets breaking loose, going adrift and space dolphins becoming entangled in them and drowning.
            • And what about spaceflies? They are already endangered by all those rogue traders flying around with spacefly collectors and using them to power their jump-drives!

            • by haruchai ( 17472 )

              "space dolphins becoming entangled in them and drowning"

              So long and thanks for all the fishnets, you BASTARDS!!

    • by Rei ( 128717 )

      Not exactly. I've been trying to dig up information on this, and as far as I can tell, the actual technology itself has nothing to do with space junk. It's just an electrodynamic space tether experiment - aka, using a charged tether to experience lorentz force as it moves through Earth's magnetic field, in order to move up and down. It does nothing to junk as it flies past. The only relation to junk is that they're thinking that they could use tether-boosted spacecraft to dock with pieces of junk, and th

      • The connection I see is that you can use it to deorbit satellites at end of life, provided the satellite was was equipped with a deployable tether. Once the tether is deployed, the deorbiting process is completely passive and automatic. This doesn't help at all with the junk that is already present however. Perhaps you could attach tethers to large existing space junk but matching orbits with them to do this would be expensive.

    • I thought the metal parts are already prone to energy loss from the eddy currents generated by the earths magnetic field and their relative speed. So they should come down automatically. Of course this doesn't apply to the non-metal parts which still can use this 'tether'.
      • The eddy currents are tiny in something the size of a satellite (or even ISS). That's why these experiements use long tethers (the one tried out on Shuttle was about 40km long).

        Deorbiting dead birds is a good idea for trying to prevent more clouds of junk, but there's a lot more stuff in orbit that's equally dangerous and hard to spot/rendezvous with. Even a paint fleck is hazardous and a solitary nut would be catastrophic. Something which can match orbits of known debris clouds and "sweep" them would be a

  • And Earth will have its wish come true: our very own debris-destroyer Gundam

    • Yep, their space junk fighting technology is called Hachimaki and is a guy with a chip on his shoulder.

  • Thought for a second Japan was sending it to ISIS .

  • Reminds me of Quark from 1978 []
    • by drewsup ( 990717 )

      OMG, thank you for prompting my brain, i was just thinking about this show the other day, but couldnt remember the name. After reading the IMDB, i was chagrined to learn Tim Thomerson from Transers fame played Gene/Jean the he/she character!

    • by MrKaos ( 858439 )
      Dammit thank you! I've been trying to remember the name of this for months! All I could remember was they were a garbage crew.
    • My first thought was the junk sweeper patrol in UFO (1969)

  • by MrLogic17 ( 233498 ) on Sunday December 11, 2016 @10:42PM (#53466411) Journal

    TFA isn't clear, and mixes terminology. The summary seems to say this will act like a net to remove many little particles, but the technology is a single tether line.

    As I recall, years ago there was a tether test that generated so much power (moving through the Earth's magnetic field) that it shorted out part of the test satellite. The goal of that test, if memory serves, was to use the tether as a propulsion/braking system. Run power through to go faster, drain power out for braking. Presumable a resistance coil / heater.

    If this is that same technology, it isn't going to do anything for debris that isn't already captured or attached to the tether. Keeping a dead satellite from becoming space junk is good, but this won't help with the countless particles out there already.

    • by drewsup ( 990717 )

      It melted the cable as there were impurities in its structure, this was also a test to see how much power was generated, which was quite a bit, it was to be used as a test bed for alternative power supply, but the variances in magnetic field made it rather unpredictable as to a stable-ish supply.

    • by AmiMoJo ( 196126 )

      There is some more info here: []

      From the statement on that site they say they want to de-orbit larger debris before it can disintegrate into smaller particles.

      I think the net idea is because of confusion about the company that made the tether, Nitto Seimo, whose main business is fishing nets. It's an impressive company, developing high tech nets and going since 1910. Still relatively small with about 250 people, and a high tech manufacturing powerhouse that manages to compete

    • Found a good link for those who want to know more: []

  • by rnmartinez ( 968929 ) on Sunday December 11, 2016 @10:56PM (#53466477)
    How hard can it be>? We'll probably need them for interstellar travel anyways :-P
    • Extremely hard. On earth, there is an atmosphere that limits the speed of projectiles. Pieces of rock in space can be sent at very large speeds at your precious spacecraft. It takes some really heavy armour plates to shield against them. And "heavy" is the dirtiest word in space travel.
      • by subk ( 551165 )

        It takes some really heavy armour plates to shield against them.

        I don't think he meant shields like Roman shields.. I think he meant shields like Star Trek shields; a field emanating from a system aboard the ship.

      • "And "heavy" is the dirtiest word in space travel."

        Only because we have to loft everything we have out there from the bottom of a gravity well and we have a pathological aversion to using nuclear bombs under a launcher.

        If raw materials are available to build stuff in-orbit or further out then the equation changes dramatically.

  • I thought of a similar plan some years ago: make a balloon out of some very thin light material, such that when inflated, it is very much larger than the satellite. When the satellite is at end of life, inflate the balloon (takes very little gas, as we're in a vacuum.) This greatly increases the drag against the very thin outer atmosphere of the earth. (The balloon will get punctured eventually by other space junk. Without testing, I don't know if it would deflate to smaller cross-section if this occurred.

    • I don't know which device would be more effective, except that my device is much more altitude sensitive than the Japanese tether, and that these people are smart enough to think of my balloon but chose to develop the tether.

      Stretchy things which behave reliably in space must be difficult to come by.

      • I didn't envision the balloon to be stretchy. Think weather balloon or hot air balloon.

        • Still has to sit folded up for years, then inflate reliably without puncturing, or layers sticking to each other.

          • Mars lander airbags have the same issue.

            If the fabric can be rigidised during inflation then punctures don't matter (it doesn't matter if the fabric isn't stretched anyway). this is the principle behind the Bigelow hab module.

            We already know of suitable materials for this job (airbags and airbag pyros). The multilayer construction necessary for a hab module isn't required for this kind of operation.

            Bear in mind that balloon deceleration will require something at least 50 feet across to bring things down fro

  • by johannesg ( 664142 ) on Monday December 12, 2016 @04:24AM (#53467467)

    After years of research capturing large objects in the oceans, and despite all the protests by nay-sayers, finally Japan is ready to take their technology into space and in the process help all of humanity...

  • by cellocgw ( 617879 ) <> on Monday December 12, 2016 @12:59PM (#53469613) Journal

    Use of trawling nets in our oceans has led to the deaths of many marine mammals,most noticeably porpoises/dolphins.

    How to they plan to avoid killing all the cute space dolphins?

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