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Engineers Working On Swarm Of Laser Wielding Satellites To Deflect Asteroids 114

Posted by Unknown Lamer
from the repelling-drakh-invasions dept.
Zothecula writes with news involving space and lasers. From the article: "A collision between Earth and an asteroid a few kilometers in diameter would release as much energy as the simultaneous detonation of several million nuclear bombs, and with the impact of an asteroid estimated at around 10 km (6.2 miles) in diameter believed to be responsible for wiping out the dinosaurs, numerous strategies have been devised to try and avoid such devastation. The latest idea comes from engineers at Glasgow's University of Strathclyde who suggest that a swarm of laser-wielding satellites could nudge Earth-bound asteroids off their collision course."
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Engineers Working On Swarm Of Laser Wielding Satellites To Deflect Asteroids

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  • by Anonymous Coward

    Sharks in space?

  • Which means more space junk. Whee!

    • by Gordonjcp (186804) on Wednesday March 28, 2012 @11:36AM (#39497099) Homepage

      RTFA, although I know this isn't a popular idea.

      The big asteroids become big asteroids moving in a different direction, and a puff of hot vapour where the laser has ablated a chunk of the surface.

      • I'm sure he was talking about the satellites themselves

        • by KingRobot (703860)
          No... read his subject line.
          • Agree, no he wasn't, but it is a somewhat valid point, unless these laser wielding satellites can be put out in Solar orbit....

            • by Baloroth (2370816)
              I'd rather have a 10km^3 of extra space junk orbiting the Earth than have 10km^3 of solid asteroid slamming into it.
            • by mhajicek (1582795)
              The dust and vapor going in the opposite direction would likely miss Earth on the other side, and would be relatively insignificant even if it did hit. We get dust and vapor hitting us all the time. Or were you talking about the satellites being space junk? In that case I'd say if we have only so many orbital slots to allocate, using several of them to stave off extinction is a better use than more spy and com sats.
              • I was thinking of the satellites - again, they might accomplish their mission better roving in a Solar orbit rather than stuck around Earth... also, I'm thinking it's going to take more than one or two big solar panel arrays to make any appreciable impact on asteroid tragectory...

      • Apparently they never played "Asteroids"...

      • by na1led (1030470)
        It would have to be a slow moving asteroid, and lasers will have no effect on comets.
      • To clarify Gordonjcp's statement, reading the f'ing article is not popular. The idea of zapping asteroids with lasers is probably a pretty popular idea around here.
        • by Gordonjcp (186804)

          Yes, exactly. No-one Rs TFM if they can help it, but zapping pretty much anything with lasers is always cool.

    • by ciderbrew (1860166) on Wednesday March 28, 2012 @12:11PM (#39497513)
      I agree space junk is a problem and we shouldn't try to make it worse. HOWEVER, several million nuclear bombs going off might make more mess and kill us all. I'm going to have to pick space junk.
  • by Anonymous Coward

    Are those friggin' satellites with friggin' lasers on their friggin...Yeah, I don't know where I was going with that.

  • by crazyjj (2598719) * on Wednesday March 28, 2012 @11:24AM (#39496991)

    "These satellites, which we will use for asteroid deflection only, not for covert assassinations or as a dreadful weapon of war, will be a vital part in ensuring the future of human civilization" said a Pentagon spokesperson. "We look forward for a chance to put these satellites, which will not be a part of any secret missile shield program nor used to destroy terrorist hideouts, into orbit to protect our planet."

    • Like the dozens of similar comments waiting to suggest that this technology could be used to target land-based settlements (although if you RTFA, it's suggested that it might not be able to) or other satellites, there will probably be a number of concerned politicians who will gun this down on the same premises. With all of the cyberwar going on these days, both intergovernmental and rogue, it seems inevitable that someone will figure out how to hijack these things. (Possibly Kevin Mitnick whistling into a

      • by Baloroth (2370816)

        It sounds like the plan is for the satellites to only be launched when an asteroid is detected incoming (probably a few months before it would hit), since they mention flying the satellites in formation with the asteroid. That means the satellites aren't a permanent thing and in fact will probably be non-functional after serving their purpose, so there really couldn't ever be any political argument against a deployment of such a system in a case of actual need (I mean a good political argument, I'm sure som

    • by ackthpt (218170)

      I don't know why they're looking at lasers, but the only idea I've heard, which sounds workable, is send up robotic rockets which attach, drive in a spike or something, and drive the thing to a new course.

      Why lasers? Do you really trust them not to ever be directed earthbound, towards some guy who has a name which rhymes with Sim Pong Nun? So very tempting and all you need is a rationalizer-in-chief to make it so.

      • by chill (34294) on Wednesday March 28, 2012 @11:47AM (#39497243) Journal

        If you look at the details, which would include the mass and velocity of the asteroid in question, you'll understand. The mass and fuel needed for such a "tug" satellite would be directly proportional and not possibly to launch, much less have extra fuel to maneuver over to the target, etc.

        They asteroids in question only look small and slow because of the incomprehensible size and emptiness of the background. That is, lack of a good reference point.

        http://www.brighthub.com/science/space/articles/64710.aspx [brighthub.com]

        • by mmell (832646)
          Um . . . okay.

          But it doesn't matter whether we use a gravity tug, a physically attached rocket tug, lasers or any other technology. At the end of the day the energy requirements are the same. We have to apply a considerable amount of force over a considerable amount of time. Even if we could come up with a long enough extension cord to plug satellite based lasers into the wall, the electric bill would be enormous. Incidentally, what's the energy efficiency on your average high-power laser? Also, how m

          • by mhajicek (1582795)
            I believe the supposition is that the lasers could act over a long time and at very long ranges when compared to kinetic methods which would have to wait until the thing got close before acting. The earlier you start pushing on the object the less you have to push in order to change its course sufficiently. As far as supplying power, in addition to solar and onboard reactors there is also the possibility of beaming energy from the ground. It would be inefficient, but then you just send way more energy th
            • wouldn't it be more efficient to have the lasers ground based and just give them extra juice to overcome any losses in the atmosphere? Seems like it would be a lot cheaper and avoid that "militarization of space" problem.

              • by mhajicek (1582795)
                Hard to maintain focus through the atmosphere. You could focus well enough to hit a collection array in LEO but probably not well enough to vaporize rock at distances measured in AU. It also occurs to me that the charging beam could be constant while the ablation beam could be pulsed for energy density.
          • by ceoyoyo (59147)

            "At the end of the day the energy requirements are the same."

            No.

            Conventional rocket: you have to haul up the fuel and the reaction mass. Also very inefficient

            Ion thruster: very efficient, can be solar powered, but you still have to haul up the reaction mass

            Lasers: probably more efficient than a conventional rocket, can be solar powered, don't need reaction mass (they use the asteroid for that)

            The amount of stuff you have to haul up to the asteroid is GREATLY reduced using the laser solution, and therefore

      • by ceoyoyo (59147)

        Lasers are more efficient because they use bits of the asteroid itself as reaction mass.

        This idea is to use lots of little lasers instead of one big one. The big one could theoretically be directed Earthward, maybe, but the little ones almost certainly can't. They're too small to have much effect through the atmosphere.

        If some military with launch capabilities wants to put lasers in orbit, you won't even know about it. Why would they advertise it by calling it an asteroid shield?

        • by kanto (1851816)

          If some military with launch capabilities wants to put lasers in orbit, you won't even know about it. Why would they advertise it by calling it an asteroid shield?

          You advertise it so you can put a bigger laser in orbit; since this is a popular threat scenario you can probably militarize the hell out of space before people wake up to object. But then again, maybe I'm a cynic.

      • I'm pretty sure the same thing that keeps that from working is the same thing that keeps us from getting cooked by the sun.
    • by madmayr (1969930)
      yep ... what could possibly go wrong?
    • by doston (2372830)

      "These satellites, which we will use for asteroid deflection only, not for covert assassinations or as a dreadful weapon of war, will be a vital part in ensuring the future of human civilization" said a Pentagon spokesperson. "We look forward for a chance to put these satellites, which will not be a part of any secret missile shield program nor used to destroy terrorist hideouts, into orbit to protect our planet."

      Meanwhile, at the UN "We other, lesser governments, know that the US is only interested in protecting ALL of us (the little people) from comets and such and not just interested in militarizing space because they just couldn't....they wouldn't." "They'd never blow anybody up with these" added Iraq.

    • by Hentes (2461350) on Wednesday March 28, 2012 @11:35AM (#39497085)

      Lasers are just a way to transfer energy and the only energy those satellites will have comes from a few solar panels. It would be too weak to pose a threat to even a single human. It could theoretically be used for targeting though.

    • by PPH (736903)
      It wasn't even a good movie [wikipedia.org] when they did it with missiles.
    • an autonomous network of satellites orbiting earth safely out of reach, with lasers powerful enough to deflect a huge asteroid - what could possibly go wrong?
  • by Kam Solusar (974711) on Wednesday March 28, 2012 @11:28AM (#39497015)
    I stopped reading at "Swarm of Laser Wielding..." when an image popped into my mind:
    A big bad asteroid hurtling towards our little blue planet. Then the camera pans around and we see a huge number of little dots. Flying closer, we see a huge swarm of frickin' space sharks swooping down towards the asteroid, shooting their lasers at it while Bruce Willis, riding the lead shark, yells "Yippee-ki-yay, motherfucker." I'd pay money to see that.
    • Much cooler than my mental image of a giant, menacing looking asteroid coming our way, and the earth turning into a giant disco ball of asteroid-destoying laser power. I have to admit, it was heavily inspired by a stage in Rez, so there was also trippy electronic music playing and flashing lights.
    • I stopped reading at, "I stopped reading at..."
  • as i remember it did not go so well hint if they look like pyramids they are a NO GO

  • We can't identify all potential large asteroids and astrophysicists have estimated those % and they are, as I recall, 10-20% of those in the Kuiper Belt.

    Even with the best defensive satellites, we may not detect a big asteroid in time to deflect it. Some significant asteroids approach from the direction of the Sun making them hard to detect.

    When the diameter of an asteroid gets twice as large, it takes 8 times the energy to alter its course a given amount and certainly has probably more than 8 times the im

  • Hm, how about practice on space junk now in orbit around earth? Less distance means you need less precise aim, and you start making a dent in all the junk in orbit. In addition you don't have to wait until there is something in range to practice.
    • by mhajicek (1582795)
      Good idea. Target practice that cleans up litter. Slow the junk down so it drops out of orbit.
  • by Anonymous Coward

    ...I deplore these aggressive measures. The better answer is to move the Earth out of the asteroid's way.

  • It's a power so great it can only be used for good or evil!
  • Where are the Spaceballs when we need them? Mega-maid will handle this!
  • Exactly how many gigatons is "several million nuclear bombs"?

    I mean, obviously it's largely irrelevant at the scales they're talking about and the layperson reads that as "several million times the hiroshima bomb" which is what they're going for. But can we stop dumbing down this shit and actually try to educate people just a little?

    • by ceoyoyo (59147)

      "I mean, obviously it's largely irrelevant at the scales they're talking about"

      The measurement is highly variable so it's not a problem to have the unit be a bit vague. You said yourself it doesn't matter.

  • ... have the LHC generate a black hole, and time it so the black hole intercepts the asteroid and eats it?
    • by s_p_oneil (795792)

      Because then we'd have a black hole heading for Earth instead of an asteroid.

      • But then we could just fire up the LHC again, and send a black hole to eat the black hole, and just repeat as necessary.
        • by s_p_oneil (795792)

          ... until the LHC breaks down (which seems to happen pretty often). You know, it wouldn't surprise me if that scenario was made into a Japanese anime movie.

  • by voss (52565) on Wednesday March 28, 2012 @12:59PM (#39498101)

    We are talking about a 400 lb payload. Compare that with the 1800 lb of a voyager probe.

    • by Bardwick (696376)
      Why would getting hit with a scorched asteroid be any different from a non-scorched asteroid?
      • by geekoid (135745)

        Properly placed, it would remove some mass from the object. Given enough time, that will changed it's trajectory. And the sooner we know, the less mass we need to change.

  • This sounds like an idea I had recently [google.com].

    I wonder if the spacecraft actually have to get close to the asteroid for this to work. I mean, once you're in orbit, you're more than half way to anywhere you want to go, but I still wonder if a system like this wouldn't be more responsive and easier to maintain if we kept it in earth orbit? Do we have lasers that won't diverge more than a meter over a few gigameters of distance?

    • This sounds like an idea I had recently [google.com].

      Actually, it sounds more like an idea Kenton Varda had :)

      Jokes aside,

      Do we have lasers that won't diverge more than a meter over a few gigameters of distance?

      No, we don't. I couldn't find numbers, but as you'd probably need lenses to produce a collimated beam it'd be extremely difficult to manufacture them with enough precision. Even a meter of divergence would be far to wide to generate enough heat to cause a burst of ejected material. According to the researchers in The Fine Article you'll want to get those lasers in as close as possible.

      • *chuckle* Well, yeah, sort of. I thought of his solution and set it aside in the hopes something earth-based could work.

        But it sounds like a collimated beam with less than a meter of divergence over gigameters is beyond current technology, and certainly not possible from an earth-based station. :-/ *sigh* That shoots (pun intended) that idea down.

        I guess getting them to the asteroid isn't too hard once they're in orbit. But it would still take a lot of time, likely months or years (even with clever stealin

  • I played this game years ago. http://en.wikipedia.org/wiki/Asteroids_(video_game) [wikipedia.org]

  • Its for... asteroids where asteroid means: hostile target.

  • all about time. IF you had enough time, you could just launch rocks and have a robot pt them on the asteroid. the increase in mass will changes it's course.

  • day of the triffids

    • Why go to the bother of lofting power supplies and creating lasers when there is a nonstop source of radiant energy at the center of our solar system?

      Just create a bunch of mirrors and point them all at the same spot on the side of the asteroid, create the big gas plume, and send it on its way.

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