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Earth Shark Space Science

California Professors Unveil Proposal To Attack Asteroids With Lasers 161

Posted by timothy
from the hitch-a-ride-to-the-off-world-colonies dept.
An anonymous reader writes "Yesterday's twin events with invading rocks from outer space — the close encounter with asteroid 2012 DA14, and the killer meteorite over Russia that was more than close — have brought the topic of defending mankind against killer asteroids back into the news. The Economist summarizes some of the ideas that have been bandied about, in a story that suggests Paul Simon's seventies hit "Fifty Ways to Leave Your Lover": Just push it aside, Clyde. Show it the nuke, Luke. Gravity tug, Doug. The new proposal is an earth orbiting, solar-powered array of laser guns called DE-STAR (Directed Energy Solar Targeting of AsteRoids) from two California-based professors, physicist Philip Lubin (UCSB) and industrial statistician Gary Hughes (Cal Polytechnic State). Lubin and Hughes say their system could be developed and deployed in a range of sizes depending on the size of the target: DE-STAR 2, about the size of the International Space Station (100 meters) could nudge comets and asteroids from their orbits, while DE-STAR 4 (100 times larger than ISS) could evaporate an asteroid 500 meters in diameter (10 times larger than 2012 DA14) in a year. Of course, this assumes that the critters could be spotted early enough for the lasers to do their work."
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California Professors Unveil Proposal To Attack Asteroids With Lasers

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  • by Anonymous Coward

    There was also a meteor that was seen from San Francisco [go.com]

    • by rcamans (252182)

      One hit Cuba as well. http://www.mirror.co.uk/news/weird-news/second-meteor-video-cuba-two-1712957. I did first ost on it, but /. never posted it.

  • by ionix5891 (1228718) on Saturday February 16, 2013 @09:28AM (#42921337)

    The Death Star

    • Re: (Score:2, Funny)

      by flyneye (84093)

      I'm thinking Atari had it before Star Wars did. Did they channel Ronald Reagan to come up with this idea?
      There are millions of "Asteroids" champs out there just drooling to do the "space drone" piloting thingy.
      I'm thinking the government knew all along and the video game was a last ditch attempt to find the ultimate savior of the world, fully trained.
      They've known about the Asteroid attack for years, recent Islamic Prophesy masks the fact that it is entirely the work of Iranians, secretly not enriching uran

      • I'm thinking Atari had it before Star Wars did. Did they channel Ronald Reagan to come up with this idea?
        There are millions of "Asteroids" champs out there just drooling to do the "space drone" piloting thingy.
        I'm thinking the government knew all along and the video game was a last ditch attempt to find the ultimate savior of the world, fully trained.

        And those of us who were pretty mediocre at the game, but were addicted to high score boards are totally screwed.

        I can just imagine this conversation taking place as I am being abducted in a black Choplifter helicopter being taken to some hidden training facility...

        "So, Scarletdown. Due to your exemplary performance on the Asteroids machine at the Truck Corral in Baker, Oregon back in March of 1980, you have been selected for our exciting new Asteroid Defense Initiative."

        "You're kidding. I always sucked h

    • by Tablizer (95088)

      called DE-STAR (Directed Energy Solar Targeting of AsteRoids)

      With a few adjustments:

      Directed Energy And Tracking Helped by Solar Targeting of AsteRoids = DEATHSTAR

    • close enough. its called the DE-STAR, star wars jokes???

      I heard there was a whitehouse.gov petition to build a death star recently. mabey it had some form of an effect?
  • Killer meteorite over Russia. Yeah, sure. In your dreams.

    • by M. Baranczak (726671) on Saturday February 16, 2013 @12:01PM (#42922017)

      Let's keep things in perspective. There are no verified records of anyone being killed by a falling meteor, ever. There are some sketchy stories that can't be confirmed - but even if we believe all of them, the number is still pretty damn small.

      Now consider all the wars, genocides, and random violence that humans have inflicted on each other.

      • by jandar (304267)

        Now consider all the wars, genocides, and random violence that humans have inflicted on each other.

        These real threats have the unfortunate feature of being changeable and measurable. Going against asteroids has no immediate measurable effect and is therefore a perfect venture for any politician.

      • by geekmux (1040042)

        Let's keep things in perspective. There are no verified records of anyone being killed by a falling meteor, ever. There are some sketchy stories that can't be confirmed - but even if we believe all of them, the number is still pretty damn small.

        Yeah, way to keep things in perspective. Here, let me paint another picture for you. If we're ever hit by a sizable meteor, there won't be any "verified records" to tend to.

        Or humans for that matter.

        So, yeah, the number will be pretty damn small. Like one. As in The One.

        Now consider all the wars, genocides, and random violence that humans have inflicted on each other.

        Yeah, I'll take my chances with the meteor, considering many of the pointless reasons we've gone to war. You'll have a better chance of changing anything talking to a rock in space.

      • by tragedy (27079)

        There is, however, a verified record of a falling meteor causing a half-megaton blast in Russia two days ago. About a hundred years ago, there was a 10-15 megaton blast, also in Russia that was almost certainly a falling meteor. That would seem to demonstrate at least some potential for destruction.

  • by Stormthirst (66538) on Saturday February 16, 2013 @09:39AM (#42921365)

    ... fricking lasers? Would there be sharks?

    • by Nkwe (604125)

      ... fricking lasers? Would there be sharks?

      Yes. Yes there would be: Sharks in Spaaaaaaaaace!

    • by mrbester (200927)

      Sharks are endangered. Even if they are to be used in a way that benefits the entire ecosystem of the planet there will be enough clamour from the hippies to prevent it. That's why Dr Evil has ill-tempered mutant sea bass.

  • Let them come! I will welcome our new overlord mineral invaders!
  • by eth1 (94901) on Saturday February 16, 2013 @09:46AM (#42921389)

    Wouldn't it be much more efficient (and cheaper) to just use mirror arrays to focus the sunlight directly, rather than use expensive and inefficient solar panels to process the sunlight into a laser first?

    Then, instead of sitting uselessly in space 99.999% of the time (or maybe 100%, even), they could focus sunlight onto ground-based power stations (or space-based, if we actually get mining operations going up there), and help pay for themselves.

    It would also be a bit harder to weaponize. A DE(ath)-STAR in orbit? What could possibly go wrong?

    • by Dan East (318230) on Saturday February 16, 2013 @09:53AM (#42921423) Homepage Journal

      What would be best is a multi-role station. The power generated when "idle" could normally be beamed down to earth via microwave, etc (if that is even possible - I assume the station could not be geostationary because of the extra propulsion required to launch so much mass to that higher orbit).

      Another use would be similar to the iss, where there are also modules for astronauts to do science in, as well as them being there to help maintain and assemble the station.

      The power generated could also be beamed to long-distance probes that use an electrical ion type drive. Any extra energy they receive from the station simply allows them to accelerate faster. That may be more feasible than beaming the power down to earth.

      • by number11 (129686)

        What would be best is a multi-role station. The power generated when "idle" could normally be beamed down to earth via microwave, etc

        For some reason, I get this image of the kid next door, the one who used to fry ants with his magnifying glass.

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          http://www.imdb.com/title/tt0246460/

          Anti-asteroid technologies' potential to unite humanity towards a common goal is usually undermined by the depressing reality that almost any technique used to prevent an asteroid strike could be weaponized, or at-least, potentially be used to create a strike deliberately.
          http://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Deflection_technology_concerns

          It remains to be seen if the baby will get killed in the cradle because of it's distrust for it's neighbors.

      • if that is even possible - I assume the station could not be geostationary

        A geostationary orbit would only be necessary if there was a single receiver on Earth. But MW receivers are far cheaper than satellites, so we could have many, all around the globe.

        because of the extra propulsion required to launch so much mass to that higher orbit

        Propulsion using standard rockets is expensive, but remember: this thing will have lots of electrical power available. So you could use that power to run an ion thruster. [wikipedia.org] It will take a while to reach the higher orbit, but the cost will be far lower than a rocket.

      • by Immerman (2627577)

        Geostationary is actually relatively cheap once you've made it to low orbit, it's just that while it's truly wonderful for the things it's good at (like "parking"communication satellites or power stations) for many applications it's not really that great - you get a half-second round-trip communication delay, you'll only ever be above one point on the equator, and it *is* more expensive to reach.

        What I'd actually expect is that a power station would be built in high LEO where it's still convenient o get to

    • by lxs (131946)

      You could always use the sunlight itself to pump your laser [wikipedia.org] skipping the electricity part altogether.

      • A more direct use of sunlight would be titanium white paintballs, to make one side of the asteroid highly reflective. Then just wait.

        We have the technology now to identify worthwhile targets and to hit them with the paintballs. The only thing we might be lacking in is caring enough about future generations to invest in something now that won't pay off for a hundred or more years.

    • It would also be a bit harder to weaponize.

      Believe it or not, I like the fact that we can weaponize it. Not because I like the idea of using it as a weapon, but because if it can be weaponized, it's more likely that it'll get funded and built. And it's something we need to have, if we want to survive. Chances are that eventually that asteroid will come. It could be 100,000 years from now, but it could also be 10 years from now.

      • Would somebody who knows a bit about laser technology speak to this question:

        Would a laser capable of slowly burning off material on a distant asteroid be suitable as a weapon against an enemy on the Earth's surface? I am guessing that beam attenuation in the atmosphere would severely limit the energy delivered to a target on the ground (but the overhead light show might be distracting).

        On reflection (pun intended) it seems this question has two parts. The second part:

        If an orbital laser weapon is develo

    • by Immerman (2627577)

      You're quite right, the raw power available via reflection is much greater for a given cost, the real problems are likely:
      Focus - a laser has an incredibly tight beam that spreads very slowly while a large parabolic reflector with variable focus that can hit something many millions of miles away with even a tiny fraction of the reflected power is probably beyond our engineering ability.
      Aim - a reflector can only target something in roughly the same direction as the sun drastica

    • by djmurdoch (306849)

      You can't focus a reflection of a light source to a smaller angle than the apparent size of the light source. From near earth, the sun appears to be about half a degree across, so the tightest focus you could achieve is also half a degree across.

      Presumably you'd want to use this at fairly large distances, say 150 million km (the distance from the earth to the sun, which is the range the lasers were to be designed for). At that distance your tightest focus would be about 1.4 million km across (the size of

  • by cohomology (111648) on Saturday February 16, 2013 @09:53AM (#42921425)

    Sorry for being a pessimist, but I'm old enough to remember Ronald Reagan's Strategic Defense Initiative.

    https://en.wikipedia.org/wiki/Strategic_Defense_Initiative [wikipedia.org]

    Consider a trillion dollar weapon of mass destruction in space.

    It will never get through Congress.
    There will be construction delays lasting a century.
    Your enemies will be able to destroy it, cheaply.
    Bright high school students will play with it.

    • What asteroids/meteors? Those were American/Chinese/N Korean missiles.

      http://worldnews.nbcnews.com/_news/2013/02/15/16977509-meteor-sparks-rumors-conspiracy-theories-in-russia?lite [nbcnews.com]

      And we haven't even heard from our 'Tin Foil Hat' brigade yet.

      This proposal would clearly be:
      - Against God's will
      - A government conspiracy to subjugate us
      - A plan by the Freemasons/Communists/Bankers/Democrats/Republicans to subjugate us
      - Contrary to a natural cycle of extinctions

      And most importantly "ALL THE PRESIDENT'S FAULT"

      Thi

      • Yeah, can we actually wait for someone to say something before we go putting words in their mouths and then denouncing them for the words we put in their mouths? Or is that not how this works? Extinct WTF
      • by MightyYar (622222)

        Just thank your lucky stars that this didn't happen 3000 years ago, or we'd have to endure another book in the bible.

        Actually, it's pretty similar to some of the existing books. Hmmm.

        • by mcgrew (92797) *

          This one [biblegateway.com] comes to mind. The difference is, Lot saw that one coming, this time we were completely off guard.

          And, you know, you only have to "endure" the bible if you actually read it. There's a lot of wisdom in that book.

          To every thing there is a season, and a time to every purpose under the heaven:

          A time to be born, and a time to die; a time to reap, and a time to sow;

          A time to kill, and a time to heal; a time to break down, and a time to build up;

          A time to weep, and a time to laugh; a time to mourn, and a

          • by MightyYar (622222)

            And, you know, you only have to "endure" the bible if you actually read it. There's a lot of wisdom in that book.

            I agree that there is a lot of wisdom there. I disagree that you can avoid it. A big to-do was made of which Bible Obama was sworn in on, just as a simple example. Not that most self-described Christians actually read it, or behave like they've read it.

            • by mcgrew (92797) *

              It's hard to avoid mention of it, but note the buzz about which bible Obama used was history, not religion.

              Not that most self-described Christians actually read it, or behave like they've read it.

              Indeed. Look at Newt Gingrich as a perfect example. I believe Pat Robertson has converted more Christians to atheism than Richard Dawkins could ever dream of.

              • by MightyYar (622222)

                It's hard to avoid mention of it, but note the buzz about which bible Obama used was history, not religion.

                Yeah, maybe not the best example. Politicians (and as you point out, even pop artists) quote from it whenever convenient. But mostly you are probably right - they just invoke God and don't actually quote the Bible.

                • by mcgrew (92797) *

                  I suspect that many of them are closet atheists.

                  • by MightyYar (622222)

                    You mean Bill Clinton, model Christian, wasn't being sincere about his church appearances??? Surely, you go too far! :)

                    • by mcgrew (92797) *

                      I'd hardly call Clinton a "model Christian", but it isn't up to me to judge him for his peccadillos. He probably is as good a Christian as me, I'm far from perfect even though I try (hell, I got seduced by a married woman last week). It seems that Christians make lousy Presidents; Carter seemed a good man, but he sucked as President. Of course, he didn't suck nearly as badly as Bush, who I don't think has a conscience.

                    • by MightyYar (622222)

                      I'd hardly call Clinton a "model Christian"

                      Sorry, that was meant to be a bit of hilarious sarcasm...

                      Bush is a good guy, but he has a very simple outlook on life. Simple people shouldn't be president. That said, Obama has not changed many of Bush's policies (which is why I didn't vote for him in the last election).

                    • by mcgrew (92797) *

                      Bush is a good guy

                      I can't agree with that. He may and probably is very easy to get along with, but enriching his cronies at the expense of the entire economy is just wrong. Bush is an oil man, gasoline prices more than quadrupled during his Presidency, and that was one of the biggest causes of the great recession. Another was slashing taxes on the rich. Starting a war with Iraq because Hussein threatened his dad was both stupid and evil.

                      Obama has not changed many of Bush's policies (which is why I didn't vo

                    • by MightyYar (622222)

                      I think China had a lot more to do with gas prices than Bush. Agreed that his motivation for Iraq seems to be at the very least, suspect.

                      Ironically, I think the first Bush was a pretty good Republican. He was willing to violate his no tax pledge for the sake of the fiscal health of the country, even if Clinton reaped most of the rewards. I think I voted for the Libertarians or something in the last election. It was definitely a 3rd party. My state was also pretty safe for Obama (PA), but I don't think I cou

          • I've never read Twilight. I still have to endure it in the sense it is a part of wider culture. It is allowed to be a part of wider culture and I have to put up with it to the extent that this represents a collection of everyone else freedom of expression. I'm allowed to not be happy about it.

            That said I agree there is some wisdom in the Bible, and some good poetry too. Same goes for the Quran and the Vedas and a whole bunch of other holy text. They didn't end up holy texts by accident.

            On the other hand you

            • by mcgrew (92797) *

              On the other hand you quoted that nice poetic section of Ecclesiastes immediately after referencing us to a section in which YHWH commits one of his minor genocides and punishes a woman for the grave sin of checking over her shoulder.

              Look at the context. You are to God what a program you wrote is to you. The "genocide" is akin to your looking at some code you wrote, saying "man, I really fucked that up" and deleting it. Lot only escaped because he did what his programmer told him to do, when Lot's wife look

              • Context? For genocide.

                You are justifying genocide, and to do it you are advocating tyranny. There is a difference between the computer programs I write and the people that YHWH mercilessly slaughters, the computer programs I write are not sentient. If I create twenty thousand synthetic intelligences and then delete them then I am guilty of genocide and an thoroughly unpleasant individual unworthy of worship.
                Why the quotes around genocide there by the way? If I intentionally slaughtered two entire cities wor

      • The best part about your article: "when something falls--it's man-made."

        Gravity is a US secret-weapon.

    • by Bomazi (1875554)

      The problem with SDI was not the science, but the political idiocy of spending a fortune undermining deterrence instead of working toward mutual disarmament, and the economic impossibility of dealing with countermeasures.

      Since you can't negotiate with an asteroid, and that they tend not to deploy decoys, this should work a lot better than SDI.

    • by geekmux (1040042)

      Sorry for being a pessimist, but I'm old enough to remember Ronald Reagan's Strategic Defense Initiative.

      https://en.wikipedia.org/wiki/Strategic_Defense_Initiative [wikipedia.org]

      Consider a trillion dollar weapon of mass destruction in space.

      It will never get through Congress.

      A measly trillion not get through Congress? Please. I've got $14 trillion in debt that says otherwise. Ronnie didn't have that.

      There will be construction delays lasting a century.

      Uh, I don't care who you ask right now, that would be called "creating jobs".

      Your enemies will be able to destroy it, cheaply.

      Given what it would be used for (saving the entire planet), our enemies would be idiots to attack that. Point taken though.

      Bright high school students will play with it.

      Well, other than Matthew Broderick, we've managed to keep all of our ICBM nuclear arsenal out of the hands of script kiddies for the last few decades, so I'd hope we would be able

  • by K. S. Kyosuke (729550) on Saturday February 16, 2013 @10:01AM (#42921459)
    Why attack asteroids with lasers? Aren't asteroids without lasers dangerous enough?
    • by youn (1516637)

      Asteroids with lasers are ok - it's sharks with lasers you have to worry about :p

  • After hacking the controls of the DE-STAR a Supervillain demands a ransom of $1 trillion or he will turn the lasers on Earth. Only an International Man of Mystery or a Double Naught Spy can save us from the photonic clutches of, who? Dr. Evil or SPECTRE?"
    Coming to a theater near you.
    • by Shavano (2541114)

      After hacking the controls of the DE-STAR a Supervillain demands a ransom of $1 trillion or he will turn the lasers on Earth. Only an International Man of Mystery or a Double Naught Spy can save us from the photonic clutches of, who? Dr. Evil or SPECTRE?" Coming to a theater near you.

      So you have to build laser systems on Earth first, capable of destroying the orbiting station. And of course, many nations must control these stations so that no country could take control of the space weapon and use it against all others. I'm excited to be part of this program! Also, these systems would be useful for attacking other countries' satellites in case of a war (or as the opening move in one).

    • I've seen this movie. I think in the end, they just end up with a house full of popcorn.
  • I think it's great: the Earth clearly needs a death star to defend against incoming asteroids, comets and meteorites.

    It will also come in handy if we ever have a rebellion against our UN space program...

  • Create an articificial cloud somewhere near Mars, of
    RFID-chips. Think of the possibilities.

  • Also, oblig: "will they use sharks too?"
  • despite all the Russian politicians drawing attention to themselves, we've just proven that even an unusually sized asteroid isn't a problem worth spending one dime solving. we can keep watch on objects over 35 meters, but anything smaller isn't worth the effort

  • by Kjella (173770) on Saturday February 16, 2013 @12:32PM (#42922165) Homepage

    If we could observe small objects to aim these things, we could also send people to bomb shelters/evacuate them that'd take a lot of the punch out of it and just brace for impact. For the really large objects then firing this laser at a dino-killer won't do anything anyway. From a WP article: "In 1998, NASA formally embraced the goal of finding and cataloging, by 2008, 90% of all near-Earth objects (NEOs) with diameters of 1 km or larger that could represent a collision risk to Earth. The 1 km diameter metric was chosen after considerable study indicated that an impact of an object smaller than 1 km could cause significant local or regional damage but is unlikely to cause a worldwide catastrophe."

    So even at 100 times the ISS with a year of advance warning, it can only prevent a smaller regional disaster (1/2 diameter = 1/8th the volume and 1/8th the energy of a 1km asteroid). It is quite probably cheaper, simpler and more guaranteed to work to slowly evacuate that region over that year or to prepare necessary shelters and supplies to just wait it out. This is just stone, not nukes so there's no radiation damage, once the dust clears you're free to exit the shelters again and while crops and animals might be lost there's no long term poisoning of the water and food chain. In short, compared to all the other dangerous places choose to live with earthquakes and volcanos and whatnot with far more immediate danger this seems like a total waste of money and effort. Now dino-killers would be nice to have a defense against, but this is not it.

    • by swillden (191260)
      If the lasers can evaporate a 500m object in a year's time, they should be able to alter the orbit of a 1 km object enough to make it miss.
  • Why do they wanna attack defenseless innocent asteroids that are just minding their own business?

  • A futile endeavor (Score:3, Interesting)

    by electrostaticcarrot (1198615) on Saturday February 16, 2013 @01:00PM (#42922313)
    The real threat is not from the occasional asteroid, but from swarms of small cometary rocks. Such swarms do not provide any single, easy target to spot and attempt to take out in advance.

    They have struck before on a larger scale - with regularity - as documented e.g. by Clube and Napier. Much of their research focused on the long-past break-up of a very large comet and the periodic intersection of Earth's orbit with its remains - which has led to cometary showers, with their impact on societies in more ways than one, also leading among other things to religious developments - ideas of gods and their actions and judgments.

    Historically, peoples have looked to their leaders to protect them from catastrophe - and when their leaders fail to do so, i.e. something happens that they simply cannot control, such as a rain of fireballs and meteorites exploding in the atmosphere, then a people will blame its leaders and get rid of them - often violently. This seems to be a basic feature of human psychology, one repeatedly seen in action throughout history.

    Knowing this, the leaders have the need to reassure their people that they have things under control - historically, there have e.g. been systems of ritual and sacrifice. Nowadays, reassurances come in a different form: That the sky is watched, that major events only happen "once in a lifetime" (or, earlier, that such things simply couldn't happen - which was long the consensus), coupled with simplistic ideas of weapons and other solutions to take out the threat - solutions that will never be adequate if/when the time comes for real. People are only too happy to play along with such reassurances, to develop them and then to take them and run with them, since the alternative is not too pleasant - recognizing that there is no way to avert such disasters when they arrive.

    A very recent book by a historian, "Comets and the Horns of Moses", discusses this whole subject, and much more connected to it. It goes into the history of cometary interaction with our planet - which has long seemed to follow cycles - and both how it has affected life on Earth and how humanity has responded to it - the social, cultural, and political dynamics involved, both in-between and during times of cometary disasters. Looking at the history and the present, it further goes into what seems likely to be coming up. I'd recommend it for the interested.

    http://www.amazon.com/Comets-Horns-Moses-Laura-Knight-Jadczyk/dp/1897244835/ref=sr_1_1?ie=UTF8&qid=1360956345&sr=8-1&keywords=comets+and+the+horns+of+moses [amazon.com]

    In the present time, one of several clues is the reported sightings collected by the American Meteor Society, which have increased roughly exponentially since 2005 - with 463 events on record for 2005, the increase accelerating year by year with 1628 for 2011 and then 2219 for 2012. Thus far this year - i.e. in one and a half month - there's been 322.
  • A space-based platform with enough power to vaporize asteroids? Is there any chance, whether intentionally or accidentally, that it could be pointed at something less asteroidal, like people?

    A more realistic and practical system would be to hit the asteroid head-on with a projectile of extremely high density, like a politician. Can you say Congress cluster-bomblet?
  • All the ideas that are brandied about are interesting, but ultimately a waste of time. The problem is much more fundamental that that. We currently do not have the capability of spotting them reliably and effectively, and no government agency is (in reality) working on fixing this rather fundamental problem - this includes NASA, we can not spot these killers by sitting on earth and looking up, we need to get a telescope up in solar orbit to find them efficiently. This means, as the world currently stands, t

  • by nanospook (521118) on Saturday February 16, 2013 @03:36PM (#42923163)
    A problem has been detected and windows needs to shutdown to protect your satellite. Error 0x00002.
  • I'll bet anyone $100USD that as soon as a project like this was approved, there'd be outraged protests from anti-U.S. countries around the world claiming that it's actually a space-based weapon that will be turned against them as a means of blackmailing them into giving in to U.S. demands. North Korea would probably have a full-on grand mal seizure over it.
  • I like the idea of taking out insurance against a possible catastrophic meteor hit.

    In previous discussions we have seen references to more 'soft-force' solutions, such as spraying paint on the meteorite to have it nudged it off course by sunlight pressure or mounting a small ion-motor on the surface.

    The more 'robust' approaches proposed here like blowing it up (opinions are sharply divided as to how much good that would do though) or vaporising it by aiming big lasers at it have a big disadvantage. They

  • Good luck getting other countries to sign onto this. There are already UN treaties about space-based weaponry. No one is going to put up with a country having giant orbital lasers which could just as easily vaporize large metropolitan areas as they could space rocks.

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