back to article Laser-zapping scientists will save the Earth from meteorite destruction

Californian scientists are testing a system this month that may save humanity in the not-too-distant future. Boffins at the Lawrence Livermore National Laboratory (LLNL) will fire up high-energy lasers to see if they can successfully vaporize rocks from outer space. But don't worry; your tax dollars aren't being used to build …

  1. redpawn Silver badge

    Big Laser

    Will the released gasses and debris scatter the laser rendering it ineffective for deflection? Is the asteroid allowed to shoot back? Is this the same laser to be used to send the postage stamp probes to other stars? Will it be directed at earth bound targets when not saving the planet?

    1. cray74

      Re: Big Laser

      Will the released gasses and debris scatter the laser rendering it ineffective for deflection?

      Depends on the lasing duration. Vaporization of metallic, siliceous, and carbonaceous asteroid materials requires high temperatures where the resultant velocities of gaseous materials (and hopefully any colder material dislodged by the gases) may summarized as "frikkin' fast." Given the vacuum and micro-gravity environment, the material is unlikely to stay near the impact point.

      Deep Impact (the probe, not the movie) used a big slug of copper to poke a comet. The mother probe spent 30 minutes around the moment of impact hiding behind its debris shield despite a "closest" approach of 500 kilometers, giving some idea how fast material is ejected from an energetic stimulation of cometary material.

      Observations were slightly hindered by continued out-gassing from the Tempel-1's fresh crater, but that's addressable with a two-pulse pattern: zap the target, then use a differently focused pulse to disperse residual fumes. Rinse and repeat. (Rule #2 - always double tap - probably works for both asteroids and Zombieland.)

      The situation would be more challenging if you tried a long-duration, continuous illumination of the target asteroid. Then you wouldn't have the opportunity for dispersion between pulses.

    2. TheVogon Silver badge

      Re: Big Laser

      "Instead the Lawrences plan to destroy meteorites"

      Presumably for values of "plan" that primarily include threats that happen to be right on top of Russia or China at the time...

  2. Michael H.F. Wilkinson Silver badge
    Happy

    Ah! Frickin' lasers!

    All we need now is sharks to mount them

    1. Little Mouse

      Re: Ah! Frickin' lasers!

      What we really need now is a small spaceship that can rotate both clockwise and anti-clockwise, and accelerate forwards.

      1. Uncle Slacky Silver badge

        Re: Ah! Frickin' lasers!

        Right on, Commander!

      2. AbelSoul
        Thumb Up

        Re: ..and accelerate forwards

        And don't forget the ability to *Hyperspace* jump to a random location.

    2. JeffyPoooh Silver badge
      Pint

      Re: Ah! Frickin' lasers!

      MHFW "All we need now [are] sharks to mount them..."

      ...on.

      Else it's a bit perverted.

  3. Pirate Dave
    Pirate

    But...

    if this laser plan comes to light, eh, what will we need Bruce Willis for?

    1. cosymart
      Happy

      Re: But...But....

      I thought he was nuked on that asteroid? You mean he might have escaped via a hidden tunnel! Wow you couldn't make it up!

      1. Mpeler
        Coat

        Re: But...But....

        Hopefully it doesn't end up as a half-asteroid solution...

        (grabs me super-duper-duper laser pointer, and me coat....I'm aff)...

        1. David Roberts Silver badge
          Coat

          Re: But...But....But....

          Are we sure asteroid approach?

  4. Doctor Syntax Silver badge

    I know the Antarctic's pretty cold but nevertheless the meteorites will have been heated up in the atmosphere before they landed. So will they be in the same state as they were in as the intended targets and if not will their behaviour be any guide as to how useful the technique actually is?

    1. DougS Silver badge

      They could grind off the ablation layer if they thought that was a problem.

      1. Neil Barnes Silver badge

        Or cut them in half with a laser.

        Oh, wait...

  5. mr.K

    Odds

    If we break history into three parts.

    1. The period before humans could do anything about this at all, i.e. all of it up to about now.

    2. From the point in time and forward where this will be trivial to detect and deflect.

    3. The period of time between part one and two.

    Given that period three is quite short in this time frame I would argue that the odds of this happening is insignificant. So, if you want to build big lasers, fine, go ahead*, but I find that justification here a little thin.

    *If you mount them on sharks however, I will call homeland security.

    1. cbars

      Re: Odds

      Argh! I hate this logic! Why do people think like this?

      The justification that something will soon be easy to do, does not mean the rational action is to wait for such a time. If we did that, we'd never do fucking anything! Come to that, we'd never have bothered chasing prey in the Serengeti (or whatever you want to call the prehistoric grasslands), safe in the knowledge that sooner or later the antelope would just wander toward us and we could kill it then.

      Let's get on with it, otherwise we'll never reach those future promises.

      Ugh......

    2. Captain DaFt

      Re: Odds

      "I would argue that the odds of this happening is insignificant."

      So there's a serial arsonist in your city, but since the odds he'll torch your house today are quite insignificant, you're quite happy to let the city wait until he's approaching your house with a gas can and lighter before they start building a fire department?

    3. Filippo

      Re: Odds

      This reasoning leads to extending period three. Potentially indefinitely. Making something trivial necessarily implies attempting to do it while it's not trivial.

    4. Alister Silver badge

      Re: Odds

      @mr.K

      I suggest you go and Google Tunguska, or if that's not close enough in time to worry you, how about Chelyabinsk.

      Both of those were near misses, that could have so easily been much, much worse. Maybe not extinction level, but seriously disruptive.

      Perhaps you might then consider the justification here to be a little less thin?.

      1. TechnicalBen Silver badge

        Re: Alister

        I think the question is, why were they near misses? If totally avoiding the problem is Sci-Fi, what can we do that is realistic to keep them down to near misses.

        Besides. If we can track them, we can know where they will hit. What is the most reliable way to avoid danger then? Fire lasers and hope for the best, or evacuate the town/city in the path? One gives a current tech and reliable method of saving lives. The other hopes for the best and that we can deflect/destroy the object.

        1. Alister Silver badge

          Re: Alister

          @TechnicalBen

          I think the question is, why were they near misses? If totally avoiding the problem is Sci-Fi, what can we do that is realistic to keep them down to near misses.

          Sadly, the nearest anyone can get to a reason why they were near misses is that they broke up before hitting the ground.

          Partially a function of their mass, size and shape, but also of their composition, initial entry speed and angle. The Chelyabinsk meteor had an estimated size of about 20 metres diameter, that of Tunguska was of the order of 60 to 190 metres long and 10 metres across. In both cases they entered the atmosphere at very high speed and a low angle of attack.

          I can see no way that humans can engineer these circumstances with any reliability within a sensible timescale.

          Besides. If we can track them, we can know where they will hit. What is the most reliable way to avoid danger then? Fire lasers and hope for the best, or evacuate the town/city in the path?

          I think you don't really have a grasp of the enormity of the effects should an event similar to Tunguska occur in a populated area. In the original event the trees, to a large extent, contained the blast, and minimized the dust cloud that was formed.

          Even then, there were widespread climate and weather disruptions for months afterwards. If a similar event happened over a city, the planet would probably go dark for weeks due to the dust and rubble thrown into the atmosphere, and that's still talking about an airburst event.

          Should a Tunguska sized meteor actually touchdown, then whichever country it hit would be mostly wiped out - note I said country, not town, or city.

          The Tunguska blast was estimated to be about 15 megatons or equivalent to roughly 1,000 Hiroshimas.

          There is no way that we could effectively evacuate the whole target area of an impact event like that.

      2. Anonymous Coward
        Anonymous Coward

        Re: Odds

        We've had plenty of asteroid hits in the past like Manson Idaho, a rock over 1km diameter making a hole 30km across - at the time of impact any living thing within about 1000 miles would have ceased to exist in a matter of seconds - and then it would have triggered global seismic and volcanic activity and massive global climate change from the atmospheric pollution.

        Estimates for the number of asteroids are around 1bn, cut that down to those over 10 metres and crossing earth's orbit and we get down to maybe 100million. A direct hit (or more likely the shock wave of it exploding before landing) from a 10 metre rock would wipe out a city. We regularly get reports of near misses of bigger rocks and often these are only identified a few days before or not uncommonly, after the event.

        So the challenge we face is complicated calculations of the gravitational effect of the planets and other large asteroids on 100million rocks of which we have identified a few %. We don't have the technology to do anything about one that represents a threat. Whatever technology and however much advance warning we might have, blasting a 100metre diameter rock travelling at 30km/second 10s of millions of km from earth into grit is a challenge even beyond science fiction and anyway the result might just be that we get hit by the thousands of fragments with equally devastating effect (Some "asteroids" are thought to be a cluster of rocks not a single body anyway - see Shoemaker-Levy 9 comet impact on Jupiter 1994 - arrived in bits over about a week).

        The good news (!) is that when the big hit comes we'll almost all be wiped out instantly. Depending on the size there may be survivors but they could be in for a pretty tough few millennia. The best response to the risk of an asteroid collision is to choose a religion that promises a good afterlife and hope you chose the right one...

    5. TechnicalBen Silver badge

      Re: Odds

      More than that. I'd argue the period of time where NEO were a danger has passed. The local neighbourhood has cleared.

      As an example of the risk, with galaxy collisions the predicted number of stellar collisions is around a dozen or two. That's very low for the amount of stars between two galaxies.

      So while were not talking about planets hitting planets (unless we reclassify Pluto ;) ). We are talking about the odds while the system is currently in a rather stable state.

      What are the simulations on collisions within a solar system with an age of ours? Unlike Galaxy collisions, we don't seem to have any local neighbours on a collision course. Most of our surrounding matter is orbiting in unison (around the Sun, or with our solar system around the Galaxy's core).

      1. Pascal Monett Silver badge

        Re: The local neighbourhood has cleared

        You might want to take a look here.

        Methinks that there are enough items on that page to invalidate your notion of "clear".

        1. TechnicalBen Silver badge

          Re: The local neighbourhood has cleared

          Thanks Pascal. It's also dependant on the notion of "near".

          I'd have to ask the probabilities or changes in those trajectories to know if they vary enough to become a risk. As said, if a galaxy collision results in no such few stellar collisions, then will we get any/many during our time on earth?

          Example, we have 8 or so planets in our solar system to see the results from. The likes of the collisions with Jupiter etc. What are the causes, what are the precursors to these events? Are there the same causes and precursors with regards to the earth?

          There may be zero car collisions in the desert. Hundreds on the freeway. But how many in my parking garage result in me being ran over or total destruction of my house?

        2. Captain DaFt

          Re: The local neighbourhood has cleared

          "You might want to take a look here."

          And if charts aren't his thing, here's a nice visual aid from NASA.

          For a clear area, it looks a bit busy.

      2. TechnicalBen Silver badge

        Re: Odds

        Finally, some food for thought. I'm in no way saying we should not try. I'm saying that we need perspective on these things. There are always things outside of out capability, but possibly too low in probability to worry about.

        Such as:

        Globally destroying solar flare, such as the recent near miss (July 2012).

        Super volcano eruption (a few candidates possible).

        Local Supernova. etc.

        These problems are not solved with bigger lasers. Some are not even solved by moving off this rock.

  6. JeffyPoooh Silver badge
    Pint

    Plans?

    "Last month Professor Stephen Hawking introduced plans for a laser system that could power spacecraft to distant star systems..."

    I'm not sure that what Yuri Milner and Prof Hawking presented last month quite achieves the level of detail that would define "plans".

    On a Plan Maturity Scale from 0 to 100, where Musk's Hyperloop is about a '12', Frank Llyod Wright's converging lines on a scrap of paper labeled 'Mile High Building' was the very definition of a '1' on this scale, the Hawking-Milner "Laser Sail Space Chip Something-or-other" concept is about 3 micro-units.

    1. allthecoolshortnamesweretaken

      Re: Plans?

      JeffyPoo, I don't quite get the finer points of the Plan Maturity Scale. Is it a scale of doability from the technical side, a scale of usefulness/sensibility, a scale of budgetability, or a combination?

      Focussing purely on the technical side, FLW's Mile High Building is way past the 90-points-mark already.

      Assuming statute mile (not nautical mile*), 1 mile = 1,609.3 metres.

      Burj Khalifa (Dubai): 830 m

      Currently under construction: Jeddah Tower, previously known as Kingdom Tower and Mile-High Tower. Jeddah Tower will be about 1,007 metres when finished. They changed the name because as Kingdom Tower it was initially planned to be 1.6 kilometres (1 mi) high, but the geology of the area proved unsuitable for a tower of that height.

      Thing is, building tall is building expensive. While the structure itself scales pretty much linear, the cost doesn't. If vou venture into the Supertall/Megatall range, we are talking the sort of cash that would buy a nuclear carrier, including the planes (if they were availiable)

      Anyway, back to the topic at hand: I notice that everyone from the original Star Wars gang is involved. So this is a also hedge to keep the funding coming, but at least it's for something useful and worthwhile this time.

      * Basically the only acceptable non-metric unit. Because it's hard to be happy when you're not using the metric system.

  7. ciaran

    Or an anti-matter beam!

    My favorite plan for asteroids is to fire anti-matter at them.

    Like anti-protons for example. Expensive to generate, and you'd have to do it on the moon, but easy to shoot and 100% of the incoming energy would be absorbed by the asteroid. If it was taken over by a mad scientist they could only attack earth's satellites, an anti-matter beam wouldn't make much of an impact on the atmosphere and would only create some gamma radiation. Same thing if the beam missed the asteroid or was dispersed.

    The effect of the beam on the asteroid would be to generate thrust, and should work even if its spinning. So it should be able to deflect the asteroid minutely. You'd have to start early, its not a quick process...

    1. Anonymous Coward
      Anonymous Coward

      Re: Or an anti-matter beam!

      You're thinking of Ghostbusters

      1. allthecoolshortnamesweretaken

        Re: Or an anti-matter beam!

        Just don't cross the streams and everything will be just fine.

    2. DougS Silver badge

      Re: Or an anti-matter beam!

      Why anti matter, when a laser beam would do the same? Or for that matter, drop a lot of white paint on one side to change its albedo and let solar radiation shove it to a different orbit that just misses Earth. If you've got time, that's probably the easiest option. Well it is, depending on how hard it is to cover a large asteroid with paint.

    3. Nixinkome

      Re: Or an anti-matter beam!

      Careful about the Sylkies!

    4. annodomini2

      Re: Or an anti-matter beam!

      Positron beam is probably cheaper and much easier to generate.

  8. James 51 Silver badge

    What happened to the plan to spray paint them?

    http://www.theregister.co.uk/2012/10/26/paintball_defense_against_asteroid_striking_earth/

    http://www.wired.com/2013/02/painting-asteroids/

    1. Cuddles Silver badge

      "What happened to the plan to spray paint them?"

      The main problem with painting asteroids, and with similar schemes involving covering them in foil or similar, is that it requires actually carrying stuff to the asteroid. And by far the biggest problem with space travel in general is that stuff is heavy and expensive to carry anywhere. A ground-based laser, or ever an orbital one, would likely be much cheaper - you can build a pretty decent laser for the hundred million or so it would cost for just a single launch with maybe a few tons of paint. Plus, a laser is reusable, and could be used for things like de-orbiting debris when not shooting asteroids.

      The biggest problem is, as usual, likely to be political. Giant space lasers are always going to have people suspicious of them, while a big bucket of paint probably won't.

  9. Anonymous Coward
    Anonymous Coward

    This:

    "There's very little known about asteroid strength," Bruck Syal said. "We're doing everything we can to know more about how asteroid materials respond under extreme conditions."

    Well, they formed from the mother of all explosions, have collided with planets, have travelled at thousands of miles per hour, for billions of years, in the inky, absolute kelven temperature hell that is deep deep space.

    I'd say they were pretty effin tough!!!!!

    1. Tom 7 Silver badge

      Re: This:

      You'd be very surprised. Many of them are simply a bunch of rocks loosely held together by static and gravity - they can be a result of the really tough ones hitting each other really hard. We've only been looking at them closely (as opposed to going Wooh) for a short while and a lot of them seem to shed stuff as they come in and then go bang - this is where the shock wave in very thin atmosphere many miles up disassociates the loose pile of junk exposing all the lumps to the intense shock and heat.

      They often do this where deceleration is a fraction of a G and the pressure is applied over a large surface. A more focussed push would break it up sooner.

  10. M7S
    Alien

    Perhaps a Grand Cannon?

    "paging Admiral Hayes"

    (Showing my age here, but I'd love to see a good quality reboot. Or even a re-run for my nipper to appreciate....)

    1. James 51 Silver badge
      Alien

      Re: Perhaps a Grand Cannon?

      Clean up the film, stick in the bits that got cut out and ignore the other parts that were bodged on to make it long enough to syndicate. Essentially the Japanese version with the dub. Now that I would pay for.

  11. Alan J. Wylie

    Solar flares

    What we need is a method of generating magnetic fields to induce a solar flare which will then act as a gas laser and take out the asteroid.

  12. steamnut

    Momentum

    I don't see what the laser could really achieve here other than a lot more bits. Unless the laser chops the object into small enough bits that will burn up on entry, then damage to the earth is unavoidable.

    Assuming that we get enough warning from our, non-existent, deep space radar system, then we need to apply a force to the object to deflect it from it's collision path with dear old earth. That needs some form of momentum transfer. At the very least we need to land something on it armed with rockets or to arrange a collision - a bit like galactic billiards.

    1. TechnicalBen Silver badge
      Mushroom

      Re: Momentum

      Creating a cloud of dust may be enough. If the dust has a different albedo to the rest of the roid, it could allow the sunlight to push it slightly.

      However the easiest method would probably be sending a lot of white paint over to it...

    2. Cuddles Silver badge

      Re: Momentum

      You don't need momentum transfer from an external source. Laser ablation propulsion works by vaporising a small amount of surface material, with the vaporised material going one way and the object going the other. This is one of the most realistic proposals for clearing junk out of orbit, and has been proposed as a way of propelling spacecraft without needing them to actually carry a power source - you just have a lump of metal facing Earth that you can fire a laser at. The important part when it comes to asteroids is knowing what actually happens when you fire a laser at it.

      https://en.wikipedia.org/wiki/Laser_propulsion#Ablative_laser_propulsion

  13. smartypants

    Alternative To destroying the asteroid

    Deflect its path so it passes near to the earth and moves our orbit out a little.

    Most of earth's time as a habitable planet is already used up, thanks to that pesky sun which is getting hotter and bigger, and it would be quite handy to be able to move earth a bit further out from time to time to offset this trend.

    Please don't ask me how to do this. It's clearly going to be very hard!

    Hopefully we'll have enough asteroids to steer on a near-collision to do the trick over the next 500 million years or so. I also suspect the odds of pulling that off to be far lower than the odds of the human race accidentally deploying all its weapons of mass destruction against itself, or of us all one day succumbing to some simple, hyper-virulent disease, as happens quite often in nature, but hey, like the national lottery, you've got to be in it to win it!

  14. VinceH Silver badge

    I propose a giant cricket bat in space.

  15. This post has been deleted by its author

  16. Bucky 2

    The challenge is that objects in space are usually spinning. Something as "small" as an asteroid may be spinning comparatively quickly. So the laser blast would have to be energetic enough to heat just a portion of the asteroid to affect its trajectory before that portion rotated away.

    Otherwise, all you get for your effort is a whole lot of nothing.

  17. Asterix the Gaul

    From Doom-sayers to Doom-makers

    By what reason do so-called 'scientist' take it upon themselves to set this planet,it's inhabitants,it's evironment on terre firma & the sky above to unacceptable risk?

    To use this 'experiment' as a model for the real thing is not valid.

    These fragments of meteorites,that have already landed on earth,does not validate the 'experiment'.

    Such fragments will be acting on matter already modified by entry through our atmosphere.

    Any meteorite fragmented by laser in it's direct approach to Earth, willl possibly fragment,with much of the matter scattering,before being set through the atmosphere, or, placed in orbit above.

    If the latter,it will endanger many orbiting satelites,possibly interupting communications & causing unnecessary dangers for any future launches from the ground.

    America,being 'America', displays the absolute arrogance of absolute power that it has bestowed upon itself.

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