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NASA Wants To Zap Space Junk With Lasers

Hugh Pickens writes "MIT Technology Review reports that various ideas have been floated for removing space junk, most of them hugely expensive, but now James Mason at NASA Ames Research Center has come up with the much cheaper option of zapping individual pieces of junk with a ground-based laser, to slow them down so that they eventually de-orbit. Mason estimates that a device to test the reversal of the Kessler syndrome could be put together for a million dollars, which would have to be shared by many space-faring nations, to avoid the inevitable legal issues that using such a device would raise. 'The scheme requires launching nothing into space — except photons (PDF) — and requires no on-orbit interaction — except photon pressure. It is thus less likely to create additional debris risk in comparison to most debris removal schemes,' writes Mason. 'Eventually the concept may lead to an operational international system for shielding satellites and large debris objects from a majority of collisions as well as providing high accuracy debris tracking data and propellant-less station keeping for smallsats.'"

148 comments

  1. Added bonus: by olsmeister · · Score: 4, Insightful

    Ability to blind and de-orbit enemy satellites in wartime.

    1. Re:Added bonus: by Anonymous Coward · · Score: 0

      Another added bonus, Shoot out the Aliens in case of invasion!

    2. Re:Added bonus: by blair1q · · Score: 3, Interesting

      Ability to blind populations on the ground in peacetime.

      This laser would have to be powerful.

      Satellites are irregularly-shaped and have flat reflective surfaces.

      See where I'm going with this?

      Not for long.

    3. Re:Added bonus: by MikeDirnt69 · · Score: 1

      And if you are good enough, can do with just one coin!

      --
      Am I eval()? - http://www.monst3r.com.br
    4. Re:Added bonus: by Anonymous Coward · · Score: 0

      As usual, the Simpsons had it right:

      The wars of the future will not be fought on the battlefield or at sea.
      They will be fought in space, or possibly on top of a very tall
      mountain. In either case, most of the actual fighting will be done by
      small robots. And as you go forth today remember always your duty
      is clear: To build and maintain those robots.

    5. Re:Added bonus: by Anonymous Coward · · Score: 0

      I see what you did there.

    6. Re:Added bonus: by GooberToo · · Score: 1

      I actually hadn't thought of that bug good point. What did occur to me was the exact opposite of that coin. Meaning, couldn't this then be used as a was to change orbits or to provide a boost in altitude?

    7. Re:Added bonus: by interkin3tic · · Score: 3, Interesting

      Ability to blind populations on the ground in peacetime. This laser would have to be powerful. Satellites are irregularly-shaped and have flat reflective surfaces. See where I'm going with this?

      Are you suggesting that governments will blind, say, protesters or peaceful people they don't like who happen to be staring at the lasers or at sattelites, which will reflect the beams into their eyes? Wow, that WOULD be a nightmare scenario, those evil bastards! So much wasted tax money! They should really stick to the low-tech grabbing them, putting them in a van, and burying them in an unmarked grave. It's SO much more efficient.

    8. Re:Added bonus: by michelcolman · · Score: 1

      And you can say "I didn't do it!", who's going to prove otherwise?

    9. Re:Added bonus: by Anonymous Coward · · Score: 0

      Um, these are ground based weapons. Though I guess we could reflect them off a shiny satellite like in "Top Secret".

    10. Re:Added bonus: by natehoy · · Score: 2

      There are already websites that track what are called "Iridium Flares" where the sun reflects off one of the boxy, shiny AT&T Iridium satellites. Focus the beam a little more and you could accomplish some fairly serious eye damage. However, aiming such a thing at a specific target for any length of time would be damned near impossible.

      If you wanted to truly permanently blind a populace, issue each of your people a 1kw aiming laser for their rifles. If you want to temporarily blind them, set up a couple of powerful spotlights on a tall building or helicopter. It's a lot cheaper and more reliable.

      --
      "This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
    11. Re:Added bonus: by Jurily · · Score: 1, Insightful

      Satellites are irregularly-shaped and have flat reflective surfaces.

      How is this not +5 Insightful already? Does anyone really think we can split or stop metal parts by shining light on them? It was a slightly less retarded idea when all they wanted to do was burn a tiny little hole into aircraft and nukes, but this is ridiculous.

      Since when does NASA take their knowledge of physics from Star Trek?

    12. Re:Added bonus: by blair1q · · Score: 1

      I'm using the word "ability" ironically.

      In fact, what I'm really saying is, there's really no safe way to use this thing on a random piece of space junk. Far too great a chance of half of its energy being reflected back into the face of one of the millions of people oooing and ahhhhing on the ground when it's fired into the sky.

    13. Re:Added bonus: by Anonymous Coward · · Score: 0

      so this would be creating the largest disco ball in the solar system?

    14. Re:Added bonus: by blair1q · · Score: 1

      The theory of it works, kinda-sorta, but only for objects for which you know all of the characteristics, and environments where everyone and everything that's vulnerable to backscatter is protected. Space-junk and satellites are basically randomized, especially when they're in a state where you have to use a ground-based laser to try to nudge them into more-quickly-deteriorating orbits.

      They might as well flash this thing at a disco ball and tell everyone to get a good look.

    15. Re:Added bonus: by Anonymous Coward · · Score: 0

      Yes, it's absolutely unpossible for them to use a laser to destroy objects traveling above the earth's surface at high rates of speed! Unpossible, I say!

      If you bothered to read the article, you'd see that they're talking about using either:

      1) A powerful-enough laser to ablate the surface of the junk enough to destabilize its orbit so it falls back into the atmosphere and burns up;
      or
      2) Using the momentum of photons from a lower-power laser over a longer period of time to slow down the junk enough to cause it to de-orbit and burn up;

      Both are certainly possible given current technology.

    16. Re:Added bonus: by EdZ · · Score: 1

      The laser would have to be focussed pretty accurately onto the satellite to be effective. After passing through a few hundred kilometres of atmosphere twice, and being hugely out of focus (i.e. diffused over a large area), the most you'd see from the ground would be a bright flash, no worse than an Iridium flare.

    17. Re:Added bonus: by rgbatduke · · Score: 2

      What? You insist on doing arithmetic? Something like P = I/c (within a factor of 2) for the radiation pressure exerted by light? So that if we make a very generous assumption of a kilowatt in a single square centimeter, we have 10^3/3x10^8 \approx 3 x 10^-6 Pa. We multiply by 10^-4 square meters (one square centimeter) and get 3 x 10^-10 Newtons. Take into account attenuation in the atmosphere and the fact that the beam is wiggling all over the place because of atmospheric thermal ripple and lensing, and you would be lucky to exert 10^-11 Newtons per kilowatt per square centimeter of laser beam.

      If our supposed space junk is travelling in an actual low orbit, it is travelling at roughly 7 km/sec. Let's assume that it has a mere 10 kg of mass -- if it is much smaller just finding it from Earth will be difficult, let alone hitting it. Lessee, F=ma, so we can give it a maximum relative acceleration of a whopping 10^-12 m/sec^2! A year, on the other hand, has a mere \pi x 10^7 seconds, and of course we can shine our laser on the object at most a few hours a day -- again, a duty cycle of 10^7 seconds/year would be enormously generous.

      This means that we can -- over a whole year -- change the velocity of the junk by 10^-5 meters/second! That's right folks, you heard it here first -- ten microns per second per year of thrust with a 1 KW laser beam 1 cm across, and downhill from there in nearly every direction.

      Of course this is still wildly optimistic. The problem is that we are exerting the thrust on the object from underneath. This is more or less at right angles to the direction of motion, and hence does very little to speed it up or slow it down. In fact, pretty much nothing. If we wait until it is directly overhead to hit it, we get the cosine of a nearly right angle as a transverse component and can only fire on half of the overhead pass before we are hitting it from the rear and speeding it up again. If we fire at an oblique angle, to get a good dot product cosine with the direction of thrust and direction of motion, we have to go through an equally oblique layer of atmosphere that both bends the laser beam (making it effectively impossible to hit the target) and attenuates the kilowatt still further (reducing efficiency at about the same rate the dot product improves).

      If the material were highly ablative, and if we could hold the beam steady enough to actually heat the object to where it boils, we could get some real thrust. Even a thin layer of actual reaction mass being boiled off of the surface would exert orders of magnitude more force than a perfectly reflected laser beam. But even orders of magnitude more thrust would almost certainly not suffice to slow the object enough to in any possible drug-addled, hallucinatory Universe make this an economically feasible, intelligent idea.

      Now I know who was using the cocaine found at NASA today. Whoever it was that dreamed this one up.

      rgb

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    18. Re:Added bonus: by bluemonq · · Score: 1

      ...except for the part where changing air currents and densities (the same reason why starlight seems to twinkle at night) distorts lasers, so there are "tracer" low-powered lasers so that the system can properly shape, focus, and aim the main beam. You think that reflected laser is going to magically focus itself after bouncing off of some junk to blind someone? Come on folks, this is basic SDI/ABL stuff.

    19. Re:Added bonus: by Aighearach · · Score: 1

      I don't know where you're going with it, but I see where you're coming from... right out your BLEEPITY!

    20. Re:Added bonus: by hedwards · · Score: 1

      That's not how that works. The likelihood of that happening is nihil. It takes a huge amount of energy to get a laser to paint the target, let alone actually cause a perceptible change in velocity, the reason being that light tends to get scattered as it passes through the atmosphere. So, in order to bounce a laser off a bit of debris in space and get it in the eyes of anybody, is more or less impossible, when you account for the loss of energy, the tiny target on both ends.

      Even when people are trying to hit larger targets at a closer distance and lower velocity, like say those morons trying to blind pilots, the amount of effort it takes is still pretty impressive, and rarely if ever do they manage to actually get it in the eye of any of the flight crew.

    21. Re:Added bonus: by holmstar · · Score: 1

      1kw?! A couple of watts would be enough to blind you, at least wherever the laser focused on your retina.

    22. Re:Added bonus: by wagnerrp · · Score: 1

      Well there is also the fact that those laser pointers paint a target half the size of the airplane at a mile out. Even were they to aim correctly, the beam would be too diffuse to be more than a nuisance.

    23. Re:Added bonus: by mysidia · · Score: 1

      Ability to blind and de-orbit enemy satellites in wartime.

      It's too slow, and any satellite with propulsion will be able to compensate. Unless your laser is powerful enough to cut up or burn parts of the enemy satellite, or they rely on unprotected optics, then it won't work.

    24. Re:Added bonus: by wagnerrp · · Score: 1

      Actually, less than a mW of sustained exposure would be sufficient to cause permanent damage. Somewhere up to around 5mW is considered "safe" as your blink reflex will happen fast enough to protect your eyes. Also, we've already got this nice stellar object about a hundred million miles out that will cause damage if you stare at it.

      At just a few kW, there is absolutely no risk of harm from this. The beam will scatter and spread on the way up through the atmosphere, hitting the object at something far less than full intensity. It will hit the object, which is not perfectly flat, nor perfectly reflective, further spreading the beam. It will have to pass back through the atmosphere, scattering further. That full 800mi+ trip will easily drop the beam the 6-7 orders of magnitude power needed to render it safe.

    25. Re:Added bonus: by Anonymous Coward · · Score: 0

      Uh huh, Nice math, very informative. Except that
      (a) The energy would come from the junk being burned by the laser, not radiation pressure from the light itself. Essentially, high-powered lasers can burn the junk intensely enough to cause nearly explosive levels of force as the material ablates away. This requires a much higher-power laser but also has a considerably more dramatic effect, which brings me to
      (b) a 1 KW laser? Seriously? The US Navy is building 35+KW lasers for mounting on ships. A stationary, ground-based (nuclear or even solar-powered system, wouldn't have to be run all the time and could be placed wherever we pleased) could run in the multi-megawatt area. Difficult to build with current tech? Yes. Feasible in the near future? Very much so.

    26. Re:Added bonus: by wagnerrp · · Score: 1

      Looking at this from a different angle, the maximum intensity of a standard class IIIa laser pointer is 2.5mW/cm. In order to achieve that density at that power rating, the reflected beam must be no larger than 50ft wide. That's two hundredths of an arcsecond. We just aren't that good, and through the atmosphere it's simply not possible.

    27. Re:Added bonus: by wagnerrp · · Score: 1

      If you read the article, they themselves say this would never be anywhere near enough power to de-orbit anything. The purpose of this is merely to nudge things into another orbit, specifically one that does not cross that of the satellite they are trying to protect. Now whether those minute changes in velocity a week out would be enough to significantly change the trajectory, and whether they would even be able to predict an orbit that accurately that far out, I can't say. It's been too long since my orbital mechanics classes, and we never did anything with such precision micro-maneuvering.

    28. Re:Added bonus: by Flere+Imsaho · · Score: 2

      Do not look at satellite with remaining eye

      --
      It gripped her hand gently. 'Regret is for humans,' it said.
    29. Re:Added bonus: by MozeeToby · · Score: 2

      The idea is not to blast debris out of the sky. The idea is to change the orbit ever so slightly using photon pressure. The laser is fired as the object comes over the horizon until the object is at the zenith. This has two effects. The obvious, since the laser is only fired until the object is at zenith it pushes against the object's orbital motion, effectively lowering it's orbital velocity. Less obvious, it pushes the satellite 'up' away from the earth. Since you aren't actually increasing orbital velocity all that this does is increase the eccentricity of the orbit. The two effects combined cause the sattelite's Perigee to be close enough to the atmosphere of the Earth that drag does the rest and de-orbits the debris.

      All with a relatively low power, and now focused laser beam.

    30. Re:Added bonus: by KeensMustard · · Score: 2

      It's safe to assume that if the US possesses such a weapon, then in a war so will the enemy - if you can build it, so can they. Doesn't sound like a winning strategy.

    31. Re:Added bonus: by Nefarious+Wheel · · Score: 1

      Forty years ago a Hughes engineer showed me a small block of steel that had been cut in half rather irregularly, as if an apprentice welder shined an oxy acetylene cutting torch on it. I enquired; he said "It's really not all that bad a cut, considering it was done from ten miles away through fog."

      Forty years ago.

      --
      Do not mock my vision of impractical footwear
    32. Re:Added bonus: by Lluc · · Score: 2

      Satellites are irregularly-shaped and have flat reflective surfaces.

      How is this not +5 Insightful already? Does anyone really think we can split or stop metal parts by shining light on them? It was a slightly less retarded idea when all they wanted to do was burn a tiny little hole into aircraft and nukes, but this is ridiculous.

      Since when does NASA take their knowledge of physics from Star Trek?

      Ever heard of a CO2 Laser?? They use them all the time to cut and weld metal. It doesn't take Star Trek technology to melt metal at large distances. http://en.wikipedia.org/wiki/Carbon_dioxide_laser

    33. Re:Added bonus: by Anonymous Coward · · Score: 0

      Especially if the terrorists use a back-door to hook it into the WOPR. Untold mayhem will ensue, including ARBPI* incidents at the principal investigator's domicile (uh-oh, I think I just created biggest inter-dimensional cross-plot-rip since the Tunguska blast of 1909).

      *accidental reflected-beam popcorn Ignition

    34. Re:Added bonus: by shpoffo · · Score: 1

      incoming warheads, too? Or is the laster too weak? (officially)

    35. Re:Added bonus: by Em+Adespoton · · Score: 1

      Less than that, as they haven't even mentioned that their laser would be based in the visible spectrum.

      However, I think they'd do better with a mirror and lens array operated from the moon, where they wouldn't be draining energy from the earth's supply and wouldn't have to deal with atmospheric interference (thus allowing them to operate at a MUCH lower power.

    36. Re:Added bonus: by Nefarious+Wheel · · Score: 1

      Hmm... atmospheric lensing. Have you ever run a laser through a lens? Didn't think so. But try it, the results may surprise you.

      --
      Do not mock my vision of impractical footwear
    37. Re:Added bonus: by cgenman · · Score: 1

      My understanding is that this is an old idea, and the core method is definitely ablation not the negligible force of radiation pressure.

      This system is intended to stop particles that are between 1 and 10 cm in diameter. Currently deployed technology allows for reliable ground tracking of debris that is approximately (supposedly) 10 cm, though proposed laser based tracking systems would detect debris in the 1 cm range. Presuming a 5x5x5 cube of solid steel, that's more like 1kg. Individual hobbyists are creating handheld personal laser strong enough to liquify bits of metal already. It's not too much of a stretch to think of a ground based laser in a housing the size of a building could be strong enough to get through the various atmospheres on a clear day and transfer that much energy to an object in LEO. And while the atmosphere is going to be fighting you every step of the way, at least the change in angle for refraction will tend to place the laser target at the front of the object. And aiming lasers and optical telescopes through atmospheric distortions is something that NASA has faced before, on their ground-based telescope initiatives. Lasers are how we aim things, and we're pretty good at it.

      The goal is to get the perigree of the orbit low enough that it skims the upper atmosphere and loses energy on its own. A small change in velocity can lead to significant orbital eccentricity, and greater eccentricity generally leads to a lower perigree.

      Obviously, I'm too tired to do the math right now. But it seems like you are dismissing the idea a little prematurely.

    38. Re:Added bonus: by rgbatduke · · Score: 1

      Actually yes, repeatedly. I've even published papers on nonlinear optics, although that is as irrelevant as your comment. What specific parts of the results are supposed to surprise me?

      Wait, I'll go upstairs and get a laser. There. Yup, fortunately it still works (my sons tend to like to play with them and run down the batteries). Lens, lens, I need a lens. Wait! I know! My reading glasses are an actual lens! Experiment: Shine laser on wall no glasses, a sharp point with the usual spackle. Shine laser on wall through lens -- OMG! How SURPRISING! The dot is spread out. Shine it through at an angle -- ASTOUNDING! The dot is smeared out sideways!

      Boy, for a second there you had me worried! I thought that perhaps "laser light" wasn't electromagnetic radiation after all and didn't obey Snell's Law (at least approximately) when it passed through dispersive media! I would have hated to have missed that when I taught graduate E&M courses...

      So now that we've established that I have indeed run a laser through a lens -- again -- and that lenses or dispersive media in general do in fact bend even laser light (which is differentiated from the usual hot random source kind only by being moderately coherent but otherwise behaves pretty much like -- light) did you actually have a point somewhere in there, lurking, waiting to be made? As in travelling through a thousand km of atmosphere on an angle through a differential gradient in density won't bend laser light, it only bends the ordinary kind enough for pointlike stars to visibly twinkle on a clear night and thereby limit atmospheric resolution through earthbound telescopes? Or were you wanting to assert that the atmosphere is incapable of deflecting light in general the 0.2 arcsec necessary to miss an order 1 m object at order 1000 km range? Or that the smearing of the beam caused by going through the curved differential gradient obliquely won't cause it to be larger than 1 m in size before it hits the target? Instead of being mysterious, try making a point.

      rgb

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    39. Re:Added bonus: by rgbatduke · · Score: 1

      Only the idea as described in the article. The questions I'd have for the very different method you describe is how you plan to find a ~1 kg chunk of mass between 1 and 10cm in size and hit it with a laser. That's something like 0.002-0.02 arcseconds, right? Pretty damn good shooting required (NASA or not) and you also have to deal with the spreading of the beam at an oblique traversal of the atmosphere, although I have no immediate sense of the order of magnitude of this. However, 0.02 arcseconds of spreading (while making it more likely to hit) also makes the intensity on a 1 cm target go down by 100 (for a 1 cm beam).

      I don't completely disrespect the idea; I think that the idea as described in the article was out of kilter with reality by orders of magnitude, because light pressure is really, really weak. It seems that you would agree with this. Perhaps what you describe might work, although then I'd still suggest that moving the orbit of the threatened satellites with light sails is a more plausible idea -- at least there one can get radiation pressure nearly all day and optimally direct the thrust, and one can be certain that you are hitting the target. How are you going to even know you are hitting the target? A 1 cm ball, even white hot on one side, 0.002 arcseconds across is going to be pretty much invisible...

      rgb

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    40. Re:Added bonus: by sjames · · Score: 1

      And you can use the system to prevent a collision with other debris to reduce fragmentation to a more manageable level.

  2. Added Bonus by Anonymous Coward · · Score: 0

    And, if development of the technology also allows the US to de-orbit other country's satellites that's all to the good. Right?

  3. get the space sharks ready! by Anonymous Coward · · Score: 0

    get the space sharks ready!

  4. Lasers by Grapplebeam · · Score: 1

    Is there any problem they CAN'T fix?

    --
    There is no -1 Disagree.
    1. Re:Lasers by f8l_0e · · Score: 2

      To answer your question, there is a reason the signs outside laser labs say "Do not stare at laser with remaining eye."

    2. Re:Lasers by Nadaka · · Score: 2

      That is a problem that lasers can fix, you will eventually run out of remaining eyes.

    3. Re:Lasers by Nidi62 · · Score: 2

      That's why you use that other universal fixer. Just cover said "remaining eye" with duct tape.

      --
      The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
    4. Re:Lasers by Anonymous Coward · · Score: 0

      Parking tickets?

    5. Re:Lasers by mangu · · Score: 1

      What if they are treating retinal detachment with laser photocoagulation?

    6. Re:Lasers by f8l_0e · · Score: 1

      Well played, Sir.

  5. Let's face it... by Anonymous Coward · · Score: 2, Funny

    ...everyone wants to zap space junk with lasers. NASA just happens to be in a better position than most to get the job done.

  6. Re:Insert shark joke here... by russlar · · Score: 0

    I tried, and found a "Lameness filter"

    --
    Anybody want my mod points?
  7. I've always said we need a Grand Cannon by GodfatherofSoul · · Score: 1

    Just never knew where we could find the protoculture to power it. Plus, it would come in handy when some pesky ETs show up looking to steal our resources and women!

    --
    I swear to God...I swear to God! That is NOT how you treat your human!
  8. Re:Insert shark joke here... by Anonymous Coward · · Score: 0

    Not really. TFA says ground-based. Everyone knows there are no land-sharks. Not yet, anyway.

  9. Re:Insert shark joke here... by elrous0 · · Score: 1

    Yeah, it's all fun and games until someone gets him it the head with an old satellite.

    --
    SJW: Someone who has run out of real oppression, and has to fake it.
  10. Shields at maximum! by Thraxy · · Score: 3, Funny

    Fire photon torpedoes!

    1. Re:Shields at maximum! by Ungrounded+Lightning · · Score: 1

      Fire photon torpedoes!

      Unfortunately, "photon torpedoes" are misnamed. They're matter-antimatter annihilation bombs. A projectile, rather than a directed-energy beam, weapon.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  11. FPS game!! by nowen2dot · · Score: 2

    Oooh! Can they set up a web interface and charge money for us to shoot them!!!?

    Who wants high score??

    --
    I've had a perfectly wonderful evening. But this wasn't it. -- Groucho Marx
  12. James Mason Continues... by Ancantus · · Score: 2, Funny

    To avoid legal incidents we will be mounting the lasers in international waters. We will be subsidizing costs by using existing biological life-forms, mainly sharks, as the key base for the laser installation. Aiming the devices will also utilize the shark's keen sense of smell to identify and destroy decaying orbital installations.

    --
    Violence is the last refuge of the incompetent. -- Isaac Asimov
    1. Re:James Mason Continues... by fragfoo · · Score: 1

      You jumped the shark with that one

      --
      Sig? Heil
    2. Re:James Mason Continues... by jd2112 · · Score: 1

      And this plan that i propose will cost (pinky to moth) ONE BIIIILIEEEON DOLLARS! (strokes hairless cat)

      --
      Any insufficiently advanced magic is indistinguishable from technology.
    3. Re:James Mason Continues... by Anonymous Coward · · Score: 0

      Time to call in the Paragon of Epicosity: http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs214.snc4/39056_148038628540375_132326176778287_459969_2806867_n.jpg

  13. And then when the rat-cats invade.. by IICV · · Score: 1

    And then when the Kzinti invade, we'll just turn the lasers on them! It's a win/win situation, really.

  14. Ah, the possibilities... by fuzzyfuzzyfungus · · Score: 2

    There are some very pricey earth-facing CCDs, behind sophisticated optics, in earth orbit. Be a pity if any of them were to catch fire...

  15. Recycled from 2000 by Bamfarooni · · Score: 2

    NASA Hopes Laser Broom Will Help Clean Up Space Debris
    http://www.spacedaily.com/news/debris-00a.html

    1. Re:Recycled from 2000 by Daniel+Dvorkin · · Score: 2

      What TFA is talking about is the same as the laser broom in the same way a street-sweeping machine is the same as a guy with a pushbroom. The goal is similar, but there's a vast difference in scale.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
  16. oblig. by memnock · · Score: 2

    Are sharks space worthy?

    1. Re:oblig. by Anonymous Coward · · Score: 0

      Frickin' worthy.

  17. Re: NASA Wants To Zap Space Junk With Lasers by shallot · · Score: 1

    Am I the only one who read this title and immediately thought of Frau Farbissina yelling "Fire the laser"? :)

  18. Prior art by inviolet · · Score: 2

    but now James Mason at NASA Ames Research Center has come up with the much cheaper option of zapping individual pieces of junk with a ground-based laser

    Pfah, this is an old idea: it's called a laser broom.

    NASA was even talking about this a decade ago, though it had a $200M price tag at the time: SpaceDaily article from 2000.

    --
    FATMOUSE + YOU = FATMOUSE
    1. re: Prior art by Anonymous Coward · · Score: 0

      ...and now the idea has been reformed to cost roughly $1M and have it's use be far less grandiose. How is that not "new"? Even more impressive to me, this is a government agent, that when faced with constraints, actually improved the idea by realizing you have to start somewhere, somehow. Most agency's would just rename the project, or wait for the diplomatic scene to change and then try to push it through again.

      Captcha: Shooters.
      Pew. Pew.

    2. Re:Prior art by BattleApple · · Score: 3, Funny

      The breakthrough is that these are the first lasers that actually make a pewpew sound.

    3. Re: Prior art by tophermeyer · · Score: 1

      The laser is $0.8 million. The tracking and optics needed to point the laser in the right direction were described as costing millions to tens of millions.

      Basically there is a piece of COTS tech that will kind of do what the laser broom would have done. Just much cheaper on a much smaller scale. Also we still don't quite know how to do it yet.

    4. Re:Prior art by Anonymous Coward · · Score: 0

      Similar idea, but with a lesser laser.

      The idea is to nudge objects out of collision courses so they don't cause more orbital junk, but instead encourages them to deorbit.

      Lesser lasers that can only nudge objects are much more less threatening politically friendly. For objects that don't have manuvering capability of their own something is needed.

  19. Re:Insert shark joke here... by blair1q · · Score: 1

    See the dept tag on the summary.

  20. One way to address the pidgeon problem. by Anonymous Coward · · Score: 0

    Am I the only one that got this image of charred feathers fluttering gently to the ground? Sizzle, poof, flutter.

    1. Re:One way to address the pidgeon problem. by Nadaka · · Score: 1

      It works for mosquitoes.

    2. Re:One way to address the pidgeon problem. by TheRaven64 · · Score: 1

      I'm not an entomologist, so I could be wrong, but I'm pretty sure that mosquitos don't have feathers...

      --
      I am TheRaven on Soylent News
  21. Re:Insert shark joke here... by yeshuawatso · · Score: 1, Funny

    How big is your "junk" that it needs to be zapped while you're in space?

  22. Missile Command interface by gsgriffin · · Score: 1

    Can just see it now....all these aging NASA guys sitting around a trackball playing Missile Command...but for real. Sign me up!!!

    --
    jsut athnoer menagiensls ltitle psrhae for you to dcoede. Why do we wtsae our tmie dnoig tihs?
  23. Re:Insert shark joke here... by natehoy · · Score: 2

    (tap tap tap)
    "Candygram!"

    --
    "This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
  24. Re:Insert shark joke here... by natehoy · · Score: 1

    Not for... (sticks pinky finger to mouth)... One MILLion dollars!

    --
    "This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
  25. One possible logistical problem... by Anonymous Coward · · Score: 0

    How are they going to get the sharks up there?

  26. Will the TSA be in charge of the "junk"? by sconeu · · Score: 1

    And China will tell the US "You touch my junk, and I'll nuke you!"

    --
    General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  27. Old idea... by Jaegs · · Score: 1

    Meh. This idea has been bouncing around for a while now: http://www.youtube.com/watch?v=UN8YIR60Ij0 Though the application demonstrated in the video was for a slightly different purpose, it would be an additional benefit, should the need arise.

    1. Re:Old idea... by Anonymous Coward · · Score: 0

      Or, we could use the Japanese suggestion, although that doesn't involve blowing shit up.

  28. Re:Insert shark joke here... by Kosi · · Score: 1

    You need to read some books from Walter Moers, a German writer. Then you'll know that a species called "shark maggots" lives on the continent of Zamonia.

  29. Auction off satellite hunting rights! by PolygamousRanchKid+ · · Score: 1

    Pay big bucks to bag an elephant? Or a rare Antarctica albino bearded clam tiger? Offer folks who have unreasonable amounts of money the opportunity to bag a satellite. It looks great mounted, up on the wall of the Africa room, next to Bambi's head. The profits could go to getting NASA back into action.

    We'll aim the laser on the satellite, Sir . . . all you have to do is pull the trigger . . .

    --
    Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
  30. Not about de-orbiting anything by PSaltyDS · · Score: 2

    In reply comments at the bottom of TFA you see they are NOT talking about de-orbiting things this way, only making minute changes in orbit to avoid collisions.

    Perhaps preventing collisions allows natural decay to remove debris faster than it accumulates, but other than that, their plan was not about de-orbit of debris.

    --
    Any technology distinguishable from magic is insufficiently advanced. - Geek's corollary to Clarke's law
    1. Re:Not about de-orbiting anything by Anonymous Coward · · Score: 0

      Exactly.

      Because how could photons originating from the earth pushing on an orbital object do anything other than move it away from the earth?

      The angular offset required to push against the forward motion of an orbiting object requires the laser to pass through so much atmosphere that it is scattered.

    2. Re:Not about de-orbiting anything by Ungrounded+Lightning · · Score: 1

      ... how could photons originating from the earth pushing on an orbital object do anything other than move it away from the earth?

      Easy:

      1) Hit it more on the leading than the trailing side. The ejected material leaves primarily forward, producing a deceleration. (This even works with just photon pressure bouncing from an ideally reflective object.) Yes you always CAN hit the leading side: The laser is not at the center of the Earth so just shoot when it's coming somewhat toward you.

      2) If it's spinning (with an appropriate range of alignments of its spin and orbital axes) it's even easie Heat a part of the face that's toward you but rotating toward the leading surface. The outgassing is directed forward while strong, and is weaker by the time it's directed backward.

      Note that a thrust away from the center of the Earth (unless it's large enough to boost the object to escape velocity very quickly) perturbs the orbit but isn't particularly significant when it comes to raising or lowering the perigee. It's the component of thrust along the orbit that is significant.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  31. I Predict by Jeremiah+Cornelius · · Score: 0

    Lots of smaller, harder to track debris, moving at higher velocities.

    Didn't these numbskulls ever play "Asteroids"?

    --
    "Flyin' in just a sweet place,
    Never been known to fail..."
    1. Re:I Predict by BlackSnake112 · · Score: 1

      They may not be old enough to have played Asteroids.

  32. Re:Insert shark joke here... by dpilot · · Score: 1

    Or worse, getting hit by a re-entering toilet.

    --
    The living have better things to do than to continue hating the dead.
  33. How about sending BB guns to the space station. by Anonymous Coward · · Score: 0

    Maybe we could just send a couple of Daisy BB guns to the International space station. When the crew gets bored they can go for a space walk and practice space debris skeet shooting.

    1. Re:How about sending BB guns to the space station. by Kosi · · Score: 1

      I'd rather use something without recoil for that, unless we want to add some astronauts to the debris.

      Oh, and I faintly remember a SciFi story about two enemies on Mars, where one misses shooting his last bullet at the other. The other one just kept talking with him, until the bullet, being fast enough to make a full orbit, hit the guy who shot it in his back. Or at least something like that, must be about 25 years ago. Anyone who knows that story here?

    2. Re:How about sending BB guns to the space station. by vadim_t · · Score: 1

      No clue, but it can't work as described.

      First, it doesn't work like that. Even without an atmosphere gravity would still make the bullet fall to the ground. To make it actually go in orbit like that, the bullet would have to reach escape velocity, which is 5 km/s on Mars. That's the heck of a gun.

      Second, Mars does have an atmosphere, which would introduce extra difficulties.

      Third, assuming they're on the ground, Mars isn't entirely flat and it'd almost certainly hit elevated terrain before it could make a whole loop.

      And from a practical standpoint, I don't think a planet where shooting from a gun resulted in the bullet orbiting the planet until it hits something would remain habitable for very long.

    3. Re:How about sending BB guns to the space station. by sconeu · · Score: 1

      If said bullet hit escape velocity, it wouldn't orbit.

      I don't have the numbers to calculate right now, but I'm guessing that orbital velocity on Mars is probably somewhere around 3.5km/s

      --
      General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
    4. Re:How about sending BB guns to the space station. by vadim_t · · Score: 1

      Oops, you're right.

      The general idea should still apply though. Some googling suggests the fastest bullets are about 1/3 of that speed. It's probably hard to get much faster than that, as wherever you are, the third Newton's Law still applies and it's rather crucial not to break your own arm when shooting the gun.

    5. Re:How about sending BB guns to the space station. by Nefarious+Wheel · · Score: 1

      I remember the story, and it Mars wasn't the venue. I think it was described as an airless moon, and the author had done the math. No clue on the title yet, sorry...

      --
      Do not mock my vision of impractical footwear
    6. Re:How about sending BB guns to the space station. by Ungrounded+Lightning · · Score: 1

      To do that you need:
        - A bullet velocity between escape velocity and circular orbit at that radius.
        - No atmosphere (which would make the orbit decay enough that it wouldn't hit the shooter).
        - A planet with no appreciable mass concentrations to perturb the orbit.
        - A shot fired nearly dead horizontal. (Too low and it hits ground before it orbits. Too high and the orbit goes through the ground behind the shooter.)

      Even then the solar wind would probably be an issue.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    7. Re:How about sending BB guns to the space station. by Ungrounded+Lightning · · Score: 1

      Oh, yeah. No spin on the planet, too.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    8. Re:How about sending BB guns to the space station. by Kosi · · Score: 1

      I'm just fond of that story. Maybe it'd work like this:

      The bullet went above target's head, with a little less than escape velocity. Then take into account the nearly non-existing atmosphere on Mars and the gravity being much less than earth's.

      Still my common sense tells me that this is not possible or at least very, very unlikely . But I remember it as a really cool story, I'd be thankful if anyone could tell me name and/or author.

  34. Lasers aimed at space by byteherder · · Score: 0

    Don't we have something like this already. Isn't it called StarWars.

  35. Re:Insert shark joke here... by Anonymous Coward · · Score: 0

    Or worse, getting hit by a re-entering toilet.

    I do believe that was "Dead Like Me"

  36. Re:i have a better use for these lazers by Anonymous Coward · · Score: 0

    Just think of them as Mother Nature's Brazilian wax. Grip 'n' rip.

  37. Or you can recycle the mass by Anonymous Coward · · Score: 0

    There's been interesting talk about trying to recycle this on-orbit material, since significant energy costs have been paid to get it up into orbit. Such a scheme would be orders of magnitude more difficult, since you're trying to do more than just roughly reduce the velocity of some object by selectively burning off its +V side, and instead you're trying to corral enough space junk into similar orbits that you can cause clumps to accrete. Presumably, the accretion would involve broader scale application of energy--off the top of my head, I'd say a shitload of directed microwaves, since directing shitloads of microwaves is something we're relatively good at, but there's no analysis behind that.

    Exciting times.

  38. What legal issues? by Kosi · · Score: 1

    Any law that forbids cleaning up space? As there is no international convention about at which height airspace ends and space starts, all should be fine if the country using such a laser only shoots stuff above it's own territory.

    1. Re:What legal issues? by Anonymous Coward · · Score: 0

      Actually, I think the Outer Space Treaty does have something to say about that.
       
      "Ownership of objects launched into outer space, including objects landed or constructed on a celestial body, and of their component parts, is not affected by their presence in outer space or on a celestial body or by their return to the Earth.
       
      Can we shoot our own stuff? I guess that depends on whether the system is tested and possible to consider a weapon, inasmuch as "(t)he establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military maneuvers on celestial bodies shall be forbidden."
       
      Keep in mind this is only one multilateral treaty- it wouldn't shock me at all if there were something much more explicit in one of our various bilateral treaties with Russia.

  39. They can fire lazers at my junk any time. by AbRASiON · · Score: 1

    They are trying to increase the size of Mr. Spaces junk right? This is what scientists do yes?
    8=====D

  40. Ground-based lasers powerful enough to... by Anonymous Coward · · Score: 0

    And China will tell the US "You touch my junk, and I'll nuke you!" ...blast orbiting stuff might also just be powerful enough to shoot down any incoming ICBMs too!

  41. Play Katamari Damacy in space with a big magnet by Anonymous Coward · · Score: 0

    Maybe we could put a big magnet in space and play Katamari Damacy with the space junk.

    http://www.youtube.com/watch?v=cwhFH75OCDs

  42. Re:Insert shark joke here... by SnarfQuest · · Score: 1

    Are sharks really accurate enough to shoot down orbital debris with a head mounted laser? If they released some piranha into the sharks tank, would that be sufficient to destroy Tokyo (is a thrashing shark with a laser as powerful as Godzilla)?

    --
    Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
  43. Prototype by Anonymous Coward · · Score: 0

    The people in my neighborhood have been running scaled down tests of this technology using laser pointers at aircraft for years.

  44. Send up a garbage scow by Anonymous Coward · · Score: 0

    http://en.wikipedia.org/wiki/Quark_%28TV_series%29

  45. Enormously stupid idea... by rgbatduke · · Score: 2

    I commented elsewhere on the actual numbers, which show quite clearly that even a 5 kw laser would exert at most completely irrelevant forces on any object large enough to actually see from earth and hence target -- accelerations on a good day of 10s of microns per second per year of radiation pressure. Having RTFA and noted all of the corrections by the authors (of the idea, if I understand things correctly) it is still an enormously stupid idea. What part of piconewton scale forces is difficult to understand?

    I give this one as an assignment for my intro physics classes -- suppose you have a megawatt laser with a beam 1 cm^2 across and mount it on the rear of your spaceship to use as a drive. Wow, a whole million watts of power! Surely that will provide the ship with all kinds of thrust!

    Sure, if all kinds of thrust is a few micronewtons.

    You'd get more thrust -- and probably more net delta-vee for any acceleration time you are willing to wait -- if you simply took the laser to the door of your capsule and threw it, as hard as you can, away.

    rgb

    --
    Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    1. Re:Enormously stupid idea... by Xtifr · · Score: 1

      Yeah, too bad they're relying entirely on light pressure, and aren't planning to take advantage of, say, the possibly-catastrophic outgassing they might get from heating one side of an object. I mean, obviously one of their main concerns is going to be not damaging the objects they're trying to destroy.

    2. Re:Enormously stupid idea... by Antique+Geekmeister · · Score: 1

      But you can use such arrays against paint, rust, frozen water, and the other dust cluttering LEO. And that should be quite detectable as "glitter" in the ordinary spy satellite monitoring of LEO, which is taken from LEO and has less relative velocity to cope with and less atmospheric distortion. So I think your premise of being able to "see it from Earth" has nothing to do with most of this debris.

    3. Re:Enormously stupid idea... by pz · · Score: 1

      A 5KW laser is surely going to cause surface vaporization and thus create potentially far more thrust that the light pressure alone.

      --

      Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
    4. Re:Enormously stupid idea... by rgbatduke · · Score: 1

      In the after-article article they make it clear that they're not trying to destroy the objects (which they cannot do in any event), and that they recognize that it would take decades to actually knock something out of orbit (a vast underestimate -- try centuries). They allege -- and I'm still having a hard time seeing it but it is barely possible -- that they can divert the orbit of something enough to prevent a collision. The after article also makes it clear that the actual cost of building a laser system to do any of this is orders of magnitude more than a million dollars -- that's the cost of just the laser, not the targeting system, which has to be just as accurate and stable as any star wars antimissile laser device. They also clearly state that they are relying on light pressure, not outgassing or heating in general.

      Changing an orbit enough to cause the junk to miss by meters instead of hit something is at least in the realm of the possible, given that tiny changes in orbital velocity can make large changes in orbital position over a long enough time base. Large at least compared to the size of a space ship.

      I'd like to see the actual arithmetic that they use to justify this, though. The piconewtons from the laser actually have to be compared to things like the piconewtons being exerted by the light pressure from Mr. Sun at this sort of scale, and the sun shines on them all of the time. The forces are likely within an order of magnitude of each other, and are comparable to the extra force you experience when you lie down on the beach at noon on a sunny day.

      rgb

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    5. Re:Enormously stupid idea... by rgbatduke · · Score: 1

      a) The article methodoology explicitly claims to be using light pressure only.

      b) If they can actually hold a 5 KW laser on target at a single point on the object it might heat it up to where ablation occurs, and yes that would produce easy orders of magnitude greater (if still tiny) thrust. However, I don't think they can come close to achieving this and they'd have to work quite hard to convince me before I was willing to drop $50-100 million dollars on the experiment. Atmospheric ripple and other sources of vibration would -- IMO -- make that dot bounce around all over the place while conductivity spreads the heating out. I'm not completely convinced they can hold it steady "on" an orbiting object at all, although this is where they would indeed be spending fifty million or more dollars for every million they spent on the actual laser. How would they even know if they are hitting it?

      In star wars type lasers, they (I'm pretty sure) shoot very brief, very high power PULSES to deliver a significant amount of heat in the very small time the laser will hit "somewhere" on the target. That might work here as well, but that isn't what the article is advocating.

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
    6. Re:Enormously stupid idea... by Xtifr · · Score: 1

      In the after-article article they make it clear that they're not trying to destroy the objects (which they cannot do in any event)

      Unless they're very large objects (very large indeed!) I would think that trying to deorbit them would tantamount to destroying them. But no, I understand that the lasers aren't intended to directly destroy the objects, which is why I mentioned outgassing.

      They also clearly state that they are relying on light pressure, not outgassing or heating in general.

      Ah, well in that case I retract my comment, but as you say, the basic idea of moving the objects enough to avoid collisions is within the realm of the possible, and I would tend to suspect that they've had people with at least a rudimentary knowledge of physics look at their plan already. NASA may be cutting corners, but I find it implausible that they'd be talking about funding for an idea that any freshman could shoot down. So, until there's evidence to the contrary, I'm inclined to mark this as plausible, rather than dismiss it out of hand, as you seemed (to me) to be doing.

      The light from the sun seems irrelevant, as it's not purposeful, though I imagine they would have to take it into account when calculating when and how (and whether) to aim their lasers.

    7. Re:Enormously stupid idea... by HiThere · · Score: 1

      Well, FWIW, the Sun does affect satellite orbits. Enough that they usually (used to?) have hydrazine rockets to adjust station keeping.

      OTOH, it doesn't affect them quickly.

      OTTH, if you de-circularize the orbit very much (and it's in LEO), then atmospheric drag will de-orbit it.

      If it's not in LEO, then you probably can't do any better than just move it into an orbit where it won't hit anything interesting. Preferable into one where it will collide with another piece of junk at 1 mm/sec or less. Then, if you're luck with your electrostatics, the two will stick together, and you'll have converted two pieces of junk into one.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
    8. Re:Enormously stupid idea... by rgbatduke · · Score: 1

      The light from the sun seems irrelevant, as it's not purposeful, though I imagine they would have to take it into account when calculating when and how (and whether) to aim their lasers.

      Interestingly (I did some more looking at this and found some articles via Google about drag forces) the state of the sun is very important to the drag force that eventually does deorbit the satellites. My point was that sunlight at low earth orbit has an intensity of roughly 1.4 KW/m^2, which is comparable to the laser intensity they are talking about, and tends to be ignored even by the people that compute this drag (suggesting that either they -- also NASA people -- are foolishly ignoring an important contribution to the overall deorbiting force mix or that it is several orders of magnitude smaller and hence negligible in the grand scheme of things. Personally, I vote for the latter. Total radiation force is order of total power divided by c in both cases independent of how it is concentrated or not, and over a day the total force exerted by sunlight is likely to have a far greater effect than the total force exerted by a laser in the two hour window that they have some sort of angle -- and I suspect that the drag force itself is greater than either one, probably by orders of magnitude (that's what I was trying to figure out by looking at the articles). But even without the articles, we can do a Fermi estimate. It apparently takes order of decades to de-orbit a satellite from e.g. 500 km due to drag forces alone, with (of course) an. accelerating degradation as it sinks down into the atmosphere. Decades of a small force accumulating to hundreds of km/sec delta-vee for large massive objects, where (say) three decades is basically a gigasecond.

      Once again F = ma, and a = \Delta v/\Delta t \approx 10^3/10^9 = 10^-6 m/sec^2. We therefore expect the average drag forces acting on a smallish 100 kg satellite to be around 10^-4 N. Compare to 5x10^3/3x10^8 = 1.67x10^-5 N from the laser, assuming no attenuation etc and it is indeed an order of magnitude smaller (and ditto for the direct force of sunlight), probably several orders of magnitude smaller from 250 km on in given an exponential drop in density and hence drag force with height. Again the drag force acts 24x7, the laser for a couple of hours a day, max, on at most twelve objects a day. On the same 100 kg object, that accumulates \Delta v at order of 10^-3 m/sec/day (multiply by 10^4 seconds in two hours, divide by 10^2 kg). A millimeter per second per day. Doing a viral estimate of the change in orbital radius, that should result in a change of around a meter in orbital radius per day, a result not incommensurate with the 10+ meters per day Fermi suggests that orbits change, on average, due to drag forces (assuming decadal decay times). A meter plus per day makes the scheme borderline plausible.

      As for ideas any freshman could shoot down -- you have heard of SDI, right? And religion? Scientists are perfectly capable of proposing things and the government is perfectly capable of spending large sums of money on the proposals even when simple computations suggest that they are implausible, and humans in general are capable of believing almost anything that "sounds good" to them. If I were a reviewer of the proposal, I'd want to see the actual computations that show that they can a) detect a piece of space junk on a collision course with a LEO asset; there's so much out there that they have to use statistical mechanics to estimate the probability of collision at this point, and not all of it is of human origin; it comes in a wide range of sizes, reflectivities, and material compositions. b) identify its orbit precisely -- and I do mean precisely, to within centimeters, while it is being slowed by drag (possibly as it tumbles), sped up and slowed down by the solar wind and solar radiation force (again in an unpredictable and even chaotic way), and even is bounced around by geomagnetic effects (especially if it is a conductor) a

      --
      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
  46. Obvious question by Baloo+Uriza · · Score: 1

    Will they be shark-mounted?

    --
    Furries make the internet go.
  47. lasers... is there anything they can't fix? by Aighearach · · Score: 1

    Niven... is there anything he can't fix?

  48. I agree by unassimilatible · · Score: 1

    Since when should countries give away their technology because of fear of lawyers? OK, this is Slashdot, so I'd better re-word that.

    --
    Slashdot "libertarians": Small government for me, big government for those I disagree with. -1, I disagree with you
  49. ablation, not photon thrust by Anonymous Coward · · Score: 0

    I think you are thinking of momentum transfered by photons, this heats part of space junk to high temperature, to vaporize. Much better thrust to energy ratio.

  50. Real Genius by Anonymous Coward · · Score: 0

    I mean... what if my "space debris" is a well calibrated reflective surface...

  51. Since most people learn science from Star Trek by jeko · · Score: 1

    Does anyone really think we can split or stop metal parts by shining light on them?

    I had a guaranteed military sale with ED 209. Renovation program. Spare parts for 25 years. Who cares if it worked or not?
                                                                                  -- Dick Jones, Robocop

    Are you kidding? This idea is brilliant. It's an impossible goal that demands huge amounts of funding which the military will find as appealing as crack-soaked catnip served on hookers. It's not a blank check -- it's a limitless credit card that will never get declined. They've been buying this schtick since Reagan. When this idea plays out -- finally, a few decades from now -- we'll just move on to promising them phasers, then blasters and light sabers.
       

    --
    He put his boots up on the table and made a face. "The sig," he smirked. "You can waste your life in search of the sig."
  52. Silly me... by Anonymous Coward · · Score: 0

    If the lasers can apply enough energy to cause a very slight (but over time significant) change in orbital velocity I'm wondering if an interconnected worldwide network consisting of dozens of these low-power stations could be used not only to clear unwanted debris from orbit but also to augment the maneuvering capacity and orbital speed of useful satellites, thus potentially extending their lifespan. Measures would of course be taken to insure that atmospheric traffic would remain safe, but if the power is so low that it takes multiple hours of focused exposure to cause a slight change in trajectory, a momentary touch (such as an aircraft inadvertently passing through the beam) might only be dangerous to eyeballs, not the structure of the craft.

    Allow any party that owns a satellite and that is potentially interested in altering it's path to invest in the project and in return be granted complete access to information regarding the activities of the network and a proportional measure of control over the system. Anybody who can launch a sat can track it independently, and the capacity of this system to alter an orbit would be dwarfed by the capacity of a functional satellite's maneuvering system, so concerns about transparency and the opportunity for mischief if any part of the system fell into unfriendly hands would be much less than with a higher-powered system.

    Of course, a quick upgrade of the system to high-power weapons could be used as a global laser Phalanx system to help defend us from all manner of rogue asteroids, Cylons, Borg, etc...

  53. "NASA Wants To Zap Space Junk With Lasers" Should by Anonymous Coward · · Score: 0

    Read: NASA Uses Story Titled "NASA Wants To Zap Space Junk With Lasers" as cover for
          "U.S. Military Wants To Zap Other Countries' Satellites With Lasers"

    I hope the Slashdot readerz enjoy this correction.

    Yours In Novosibirsk,
    Philboyd Studge, C.I.O.

    P.S.: Newt Gingrich For President!

  54. Re:Insert shark joke here... by dpilot · · Score: 1

    You got it! You win the prize!
    No Whoooosh! for you!

    --
    The living have better things to do than to continue hating the dead.
  55. Re:Added bonus: ...you know all characterist... by Anonymous Coward · · Score: 0

    Here's how to find out: shoot it. Check to see the effect. If it's not what you want, shoot it at a different time or when its inclination is different. Lather, Rinse, Repeat until it moves the way you want. They're talking a 5 kW laser, repeated shots to gently push... Patience is the name of the game anyway. I'll bet that after 3-4 hunnert kibbles get shot down, they'll figure out a standard profile to follow.

  56. Re:"NASA Wants To Zap Space Junk With Lasers" Shou by PPH · · Score: 1

    U.S. Military Wants To Zap Other Countries' Satellites With Lasers

    Just keep your satellites on your side of the damned planet and there won't be any trouble.

    --
    Have gnu, will travel.
  57. Re:What legal issues? ooopsydoodles... by Anonymous Coward · · Score: 0

    I just shot your "research" satellite into a slightly useless orbit by accident. Too bad, you mighta got some good shots of my kid sister sunbathing in the ....
    Sad to say it happened 48 times in a row accidentally, using up all of yer satellite's fuel for correcting its orbit. That's why- also to be sure it won't be used as a gen-yew-whine weapon. Read "Farside Cannon" by I-don't-rememeber.

  58. Arms race? by Anonymous Coward · · Score: 0

    After 50 comments there is none which asks if this could start an arms race or should Korea deem it an act of war etc etc. Oh, never mind it is us not China doing it, so it must be alright for other countries not to wet their pants.

  59. Re:Insert shark joke here... by Nefarious+Wheel · · Score: 1

    Or worse, getting hit by a re-entering toilet.

    Or an Icy BM.

    --
    Do not mock my vision of impractical footwear
  60. oblig - oblig by formfeed · · Score: 1

    Are sharks space worthy?

    You are mistaken. NASA is planning to use laser cats.
    - I hope they give credits to the two geniuses who developed them.

  61. it's already been done. by uniquegeek · · Score: 1

    This was an episode of Futurama.

  62. But why do they care? by Anonymous Coward · · Score: 0

    But why do they care?

    It's not like they can orbit anything any more anyway.

    Maybe once NASA creates a new orbital capability, it'll become an issue again, but it's not a problem for the forseeable future, unless they are contracting themselves out to a country with a space-launch capability.

    --AC

  63. Re:Enormously stupid? - NOT by DarkStarZumaBeach · · Score: 1

    Not that stupid when the laser is a dynamically tunable Free Electron Laser (FEL) with two 10 Megawatt nuclear reactors behind it. With the number of ballistic nuclear submarines scheduled for decommissioning - there are a few that can be refit and put back to sea, with installations of orbital reaching FEL systems.

    Besides, no one expects that punching holes in space junk with a static laser beam will amount to anything.

    The key is that a FEL can be tuned to vaporize any material within its deliverable power range. Because it is tunable through tuning the frequency of the microwave resonance cavity used to capture and pump excited electrons - the delivered frequency can be boosted well into X-ray frequencies with sufficient power.

    The optics system would "paint" the target - to create a reaction force by vaporizing the surface material. With dynamic feedback, the optics would be driven to selectively paint different surface regions as the target spun in orbit - and thereby cumulatively direct the change in orbital velocity required to drop a target into the upper atmosphere: Every available square centimeter of target could be turned into a precise reaction motor. This would effectively kick the can out of orbit.

    This also should tell the audience a lot about the state of defense optics now orbiting in space, when defense contractors can propose real-time control systems that depend on "seeing" rapid velocity changes in a basketball-sized object over 24,000 miles high in orbit. Remember that there were originally only 3 mirrors created for the Hubble Space Telescope - and NASA has just one of them.

    BTW: FEL's were first discussed in A.E. Van Vogt's "Weapon Shops of Isher" (1951) - an interesting spin on Pres. Dwight D. Eisenhower's warning about the modern military industrial complex and its threat to the practice of governing a democracy through fear, intimidation, and corruption.

    Of course, NASA isn't in the business of space defense - but the US Navy is - having effectively demonstrated a working tactical satellite defense against a real failed US recon satellite before the US Air Force could - thanks to the systems programming ingenuity of Raytheon Missile Systems.

    Then again, space aliens wouldn't expect their orbiting derrieres roasted by a hidden submersible fleet.

    The Weapon Shops slogan??

    "The right to own weapons is the right to be free!"

    --
    DarkStarZumaBeachSurfinApocalypseWow
  64. Carrefull oops bombing trick by Anonymous Coward · · Score: 0

    With such a device, they will get an escuse to bomb other people satellites. "Oops miscalculated trajectory, we are sory !" And this will create more debris and more job for them hence more money. Regulators should be carrefull at that

  65. Re:Insert shark joke here... by elrous0 · · Score: 1

    Are you kidding? That's a free ticket to be young forever!

    --
    SJW: Someone who has run out of real oppression, and has to fake it.